text:
Lucy Cranwell in group portrait of Auckland Museum staff.
August 7 1907|
Henderson, Auckland, New Zealand
June 8, 2000 (aged 92)|
Tucson, Arizona, USA
|Residence||New Zealand, US|
|Alma mater||University of Auckland|
|Known for||Palynology, Flora of New Zealand|
|Institutions||Auckland Museum, University of Arizona|
Lucy May Cranwell (7 August 1907 – 8 June 2000) was a New Zealand botanist responsible for groundbreaking work in palynology. Cranwell was appointed curator of botany at Auckland Museum in 1929, when she was 21 years old. As well as her work on ancient pollen samples she was responsible for encouraging a love of botany in a generation of Auckland children.
Early life and education
Cranwell was born in Auckland, New Zealand in 1907. She grew up in Henderson under the strong influence of her conservation-minded and artistic mother. It has been suggested that Cranwell inherited the unpredictable aspects of her fearless and adventuresome spirit from her mother's Cornish roots. Her father was a trained nurseryman who had planted an extensive orchard in the family property. She attended Henderson public school and then Epsom Girls Grammar School. She entered the University of Auckland in 1925 where she undertook an initial BA degree that was a mixture of English and Botany, followed by a masters in Botany with a thesis on the epiphytes of the Waitakere Ranges. She graduated in 1929.
During her university studies she developed a love of tramping and gained a reputation as the strongest, fastest walker in the University Field Club. Her love of the New Zealand wilderness stood her in good stead for the many botany field trips she began to embark on, most often with fellow botany student and friend Lucy Beatrice Moore, to various remote and inaccessible parts of the country.
In April 1929, a few weeks after graduating, the director of the Auckland Museum, Dr Gilbert Edward Archey, offered Cranwell the inaugural Botany Curator position. The museum was due to open in its new, much larger, war memorial building in November of that year and its halls were in need of filling with displays.
"Everything had to be done on a shoestring, alas, and there was no artist to help make the cases look seductive for man, woman, or child. People did not seem to take notice, however. Dr Archey had stressed that we were to consider ourselves the servants of the public; we were to welcome enquiries of all kinds," wrote Cranwell of those first few months in the job.
As well as finding botanical specimens for display she also set about organising the Cheeseman herbarium of about 10,000 specimens. During her 14 years as botany curator she Introduced "botany trots" for children to places like Rangitoto Island in the Hauraki Gulf, wrote weekly short articles for children about plants for the Auckland Star newspaper, and collected over 4000 plants for the herbarium during her 14 years as the botanist.
Cranwell's field work was among the first and certainly the most extensive undertaken by a woman scientist in New Zealand. These included trips into the pristine, ancient podocarp forests of the King Country looking for root parasites, various trips to Te Moehau peak on the tip of the Coromandel peninsula where she documented the unique alpine flora found there, and several visits to Maungapohatu in Te Urewera. She also undertook a study of marine algae of New Zealand's northern islands (a green and a red algae are named after her), surveys of Auckland Harbour and its west coast between Muriwai and Piha, as well as several trips to take fossil pollen samples from South Island bogs.
Field trips in the 1920s and 1930s were tough assignments. Cranwell and her botanical companion Lucy Moore often slept out in the open in canvas sleeping bags, occasionally waking up covered in frost. Her field experience led her to be a conservationist recognising early that possums and wallabies represented a serious threat to the biodiversity of New Zealand forests.
During a trip to Europe, which included attending the International Botanical Congress in Amsterdam in 1935, she was invited by Professor Lennart von Post of Stockholm to learn his method of fossil pollen analysis . With knowledge of this new field study, palynology, Cranwell opened up a whole new field of botany in New Zealand. Her work analysing pollen taken from the sediment in bogs revealed the past botanical assemblages in New Zealand and aided an understanding of New Zealand's past as part of the supercontinent of Gondawana.
She was made a Fellow of the Linnaean Society (London) in November 1937, "in recognition of botanical research work done both in New Zealand and Sweden and because of efforts she has made to stimulate interest in botany through her position at the Auckland Museum." In the same year she won New Zealand's premier conservation award, the Loder Cup. She was awarded the Hector Medal from the Royal Society of New Zealand in 1954, the first woman ever to receive this honour.
War effort and marriage
Cranwell's war effort during WWII was to research to and prepare a booklet for downed allied airmen called "Food is Where You Find It: A Guide to Emergency Foods of the Western Pacific". It detailed, with illustrations, what fish and foods the downed pilots with could eat. The booklet proved extremely popular and five facsimile impressions followed the initial print run of 5000 copies.
Cranwell married Captain (later Major) Samuel Watson Smith (1897–1993) of the 13th US Airforce, a lawyer and later eminent researcher in archaeology, in 1943 and moved to the United States in 1944. They had one son, Benjamin Watson Smith. After working at Harvard University Cranwell became a Research Affiliate in palynology at the University of Arizona, Tucson. She earned international recognition for her work in this field, particularly on Gondwanan plant microfossils.
- Obituary in the Yearbook of the Academy Council of the Royal Society of New Zealand 2000
- Obituary by Ewen Cameron in the New Zealand Journal of Botany _URL_ dead link]
- University of Arizona obituary _URL_
- "Food is where you find it : a guide to emergency foods of the Western Pacific". Auckland War Memorial Museum. Retrieved 2015-11-16.
- IPNI. Cranwell.
- Information on an exhibit held at the Auckland Museum about Lucy Cranwell
- Lucy Cranwell - Pioneering young curator, adventurous and outstanding by Ewen K. Cameron, Auckland War Memorial Museum.


text:
What is a theme, anyways?
With UI theme designer you can easily adapt the user interface of SAP Fiori applications to your corporate branding. In this process you create a custom theme based on an SAP theme.
This post gives an overview of what is part of a theme, and what parts can be actually adapted in a custom theme:
- theming parameters like colors and metrics,
- assets like fonts and icons, and a
- guideline that decides how applications should arrange their UI.
With that the folder structure of a theming-repository like the one in the open-source theming-base-content can easily be understood.
The first thing that comes to mind that describes a theme is the set of theming parameters. I described an evolution of the parameter set in Semantic theming with theming-base-content.
Of the 753 available theming parameters (analysis based on theming-base-content 11.1.38), 673 are available for custom-theming in Morning and Evening Horizon, the latest SAP theme, which is near to 90%.
A general rule of thumb is: the lower the impact of a theming parameter is, the higher is the possibility that it is available for custom-theming.
That means that almost all 602 colors, from very specific parameters like _USER_ to very broad parameters like _USER_ are theme-able.
Also the most important of the 63 font parameters are theme-able. Although technically you could destroy your UI with them by increasing _USER_ or using Comic Sans as _USER_.
Even most of the 41 dimension parameters like border widths and border radii are theme-able. They should be handled with care, as an insane border-width easily distorts the carefully crafted application UI.
That is also why no metric parameters are theme-able. Parameters like _USER_, which should define the height of all "single-line" controls/components ("elements"), exist for consistent theming when a new SAP theme is envisioned, but they are to be handled so carefully that even we refrain from changing them too often.
A theme is more than its set of theming parameters. There is also a set of assets associated with a theme. Usually not with a single theme but at least with all SAP themes of the same theme family (e.g. all Horizon themes).
Most assets are not (easily) available for custom theming. Things like the 72 Font Family are core to the Fiori design language and also have a lot of accessibility considerations associated with them. To change them you have to resort to hacks like embedding the whole font as base64 in custom CSS as described in Add custom font in theme design in SCP (approach).
We know about the need to upload a custom font, especially for the SAP-icons. But the requirements to create an enterprise-ready solution for that are larger than what we can fulfill in the short term.
What can be uploaded already is a company logo. This is stored together with the custom theme and available for the SAP Fiori Launchpad.
Not immediately obvious, but for existing applications more than relevant, is the guideline that is associated with a theme (or again: with a theme family). It describes how parts of the UI should be laid out, and can change drastically between theme families.
The guideline affects for example
- the positioning of "closing actions",
- the height of table rows,
- the use of text instead of icons,
- the placement of alert messages or
- the whole structure of value helps.
From the perspective of the theming-base-content the guideline is just a single word at the right place (in the tags of a theme – here you also see that a guideline can span more than one theme family: Morning Horizon implements the Fiori_3 guideline that was introduced with Quartz and even retrofitted to Belize). But from the application framework perspective this guideline influences a lot of rendering decisions.
Implications for theming repositories
With theming parameters, assets and guidelines in mind, we can take a look at the structure of a theming-repository: the content of theming-base-content:
- Base/baseLib is the only framework and library in the theming-base-content, it serves as the root for all deriving frameworks, libraries and thus custom themes (e.g. custom themes of UI5/sap/m technically reference Base/baseLib).
- Inside is a long list of themes (with their technical ids):
- sap_horizon, which is Morning Horizon, next to
- sap_base_fiori, which is used by some frameworks as an abstract parent theme for the Quartz and Belize family, together with
- baseTheme, which is the "mother of all themes", where as many theming parameters and assets are defined and then shared with all other themes,
- and many many others.
- Inside a theme are
- parameter values in the base.less file,
- fonts and assets that apply only to that theme (or that theme family if they are referenced from a deriving theme), and
- the.theming file that describes the theme itself and contains e.g. the guideline information.
And then inheritance comes in to play and shared assets are stored at shared places. E.g. the 72 Font Family is not part of Horizon or Quartz or Belize theme family, but instead stored directly in baseTheme, because it is so central to the SAP Fiori experience. On the other hand, the Horizon family comes with a revised set of SAP-icons, so these are stored with Morning Horizon (as the base for Horizon themes).
This allows resource sharing and an efficient storage mechanism for SAPand custom themes.
We saw that a theme is more than its parts, it consists at least of
- a set of theming parameter values,
- assets and
- the guideline.
This is reflected in the structure of theming-repositories like the content of theming-base-content, where inheritance and resource sharing make storing themes efficient.
Let me know about your experiences with custom themes. Leave a comment on what parameters you are most likely to custom theme, or which assets you would really like to upload. I'm curious about your insights!

source: openbmb/Ultra-FineWeb


text:
ANSI Common Lisp 4 Types and Classes 4.4 Dictionary of Types and Classes
- Class Precedence List:
The type class represents objects that determine the structure
and behavior of their instances. Associated with an object
of type class is information describing its place in the
directed acyclic graph of classes, its slots, and its options.
- Allegro CL Implementation Details:


bee fly
Also found in: Thesaurus, Encyclopedia, Wikipedia.
bee fly
n.
Any of various flies of the family Bombyliidae that resemble bees, feed on nectar and pollen, and have larvae that are parasitic on the eggs and larvae of bees, wasps, and other insects.
bee fly
n
(Animals) any hairy beelike nectar-eating dipterous fly of the family Bombyliidae, whose larvae are parasitic on those of bees and related insects
bee′ fly'
n.
any of numerous dipterous insects of the family Bombyliidae, some of which resemble bees.
[1850–55, Amer.]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.bee fly - hairy nectar-eating fly that resembles a beebee fly - hairy nectar-eating fly that resembles a bee; larvae are parasitic on larvae of bees and related insects
fly - two-winged insects characterized by active flight
References in periodicals archive ?
Males' success locating a female bee fly drops in the presence of deceitful daisies, researchers from South Africa's Stellenbosch University report in the March 22 Proceedings of the Royal Society B.
Gustave watched the bee fly away, dizzy with nectar.
In the end, I let the greedy bee fly away, despite feeling certain that it would return to sting me.


IUCN threat status:
Not evaluated
Read full entry
Phaneropterinae is a subfamily of bush crickets or katydids. Belonging to the family Tettigoniidae, they have nearly 2060 species in 85 genera throughout the world. They are among the largest winged katydids.
The name Phaneropterinae is based upon the old world genus Phaneroptera meaning visible wing referring to the exposed tips of the inner wings.
Their legs vary from genus to genus but the front and middle ones are always much shorter than the hind ones. The ovipositor and male genitalia are also variable depending on the genus.
The katydids are arboreal in habitat with the vast majority of them passing their lives in shrubs and trees feeding on leaves and tender twigs with a potential for causing much damage when present in large numbers. This is rare, however as they live a solitary life unlike meadow grasshoppers and are thus seldom noticed by man.
Adult Phaneroptera sp with eggs
The Phaneropterinae differ from locusts in their habits of oviposition. Their eggs are rarely deposited in the earth or twigs but are either glued fast in double rows to the outer surface of slender twigs or are inserted in the edges of leaves.
Source: Wikipedia
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to calculate percentage. Several replicate measurements are needed to increase precision. Densiometer measurements are influenced by adjacent canopy height and tend to overestimate canopy cover because canopy is viewed at an increasingly oblique angle toward the edges of the mirror. Photos taken with a hemispheric or fisheye lens can be used in a similar fashion, except that canopy cover is evaluated on the images rather than directly in the field. Hemispheric photos have the same biases as spherical densiometer measurements. Bias can be reduced by using a smaller view angle (about a 10 degree arc), which reduces bias associated with oblique viewing angles.
The densitometer provides a point measure of canopy cover. The densitometer is a small sighting instrument with crosshairs and a bubble level that allows the observer to determine whether canopy is present directly overhead. This instrument is sometimes referred to as a moosehorn, and several variants exist. Since the densitometer measures canopy presence at a single point, multiple sample points must be measured to obtain a canopy cover estimate. Sample points can be spaced along a transects (see the example Measurement of canopy cover at the edge of pavement (CCEP)) or arranged in a grid pattern to obtain an estimate for a large area. Using a densitometer is directly analogous to using the dot grid method to estimate canopy cover from aerial imagery. Consequently, sample size considerations are the same as discussed for the dot grid method.
Tree diameter (DBH)
Tree trunk diameter at breast height (4.5 ft height if English units are used) is one of the most commonly measured tree size statistics. However, tree form, ground slope, and other factors can complicate this measurement. We have developed a Simplified guide to measuring DBH that discusses a number of these common issues.
Tree height
There are many methods for measuring tree height. Tree height can be measured directly with a calibrated measuring pole or indirectly through trigonometric relationships by using a clinometer or a similar device. Many websites describe methods for measuring tree height..
Tree condition/health
Evaluating tree condition is always a subjective enterprise, because such evaluations rely on visual assessments made by observers. The simplest scales rate the condition of living trees as good, fair, or poor. If more detail is needed, various aspects of tree condition are independently rated. Certain ratings (e.g., canopy thinning or live crown ratio, decay ratings) provide information about chronic health problems, whereas others (e.g., current season foliar symptoms) reflect recent health impacts. Quantitative rating scales (discussed below) can simplify assessments and reduce variability between different observers.
The USDA Forest Service Inventory and Analysis program has developed detailed standardized methods for rating tree condition and many other tree and plot factors. Illustrated manuals describing these methods in detail are available online. Detailed scales for evaluating tree health and condition developed by The Urban Forests Centre at the Faculty of Forestry, University of Toronto, which are part of the Neighbourwoods inventory program, may be available on the Internet. The Neighbourwoods program is designed to minimize bias among different surveyors. This website includes scales and in some cases photographs for evaluating the following conditions:
Hazard trees
Some of the factors listed above relate directly to a tree's hazard rating. An illustrated guide to hazardous trees is available online at the USDA Forest Service St. Paul Field Office web site. ISA publishes a widely-used guide titled "A Photographic Guide to The Evaluation of Hazard Trees in Urban Areas, 2nd edition". This publication can be ordered from ISA.
Proximity to infrastructure and hardscape damage
Conflicts that develop between trees and infrastructure are often evaluated in ground surveys. The proximity of overhead wires, buildings or other structures, other trees, traffic signs, and sidewalks and curbs can all require management actions to maintain public health and safety or tree health. Distances between trees and various hardscape elements can assessed by measuring distances directly (using tape measures, distance measuring wheels, or rangefinders) or can be rated qualitatively based on visual inspection (not a problem, potential/future problem, current problem). If damage or conflicts are present, the nature and extent of the problem can also be noted and prioritized for corrective action.
Rating scales
Various types of tree assessments do not lend themselves to direct measurement but can be estimated visually. For instance canopy dieback, an important tree health parameter is difficult to measure directly but the percentage of the canopy affected by dieback can be estimated by a trained observer. Other assessments, such as canopy cover, can be assessed using reasonably precise methods, but the amount of time and effort required may not be justified based on the use of the data. In such cases, ocular estimates may be used even though more precise methods are available.
As noted above, visual rating scales can be developed for many of the assessments that are made in ground surveys. Qualitative rating scales can be quite objective if only the presence or absence of a characteristic is noted (e.g., presence/absence of leafy mistletoe). Subjective qualitative scales (e.g., rating mistletoe infection as light, moderate, or heavy) are also commonly used, but it can be difficult to obtain consistent ratings from multiple observers when subjective scales are used. However, such scales can be useful if qualitative categories are augmented with more quantitative explanations (e.g., light mistletoe rating=less than n infections). Photo keys that illustrate different qualitative rating classes can also help make qualitative ratings more objective and repeatable among different evaluators.
Quantitative rating scales are also commonly used. Scales are used to simplify the estimation of quantities such as counts or percents. Different types of scales ay be appropriate for different types of ratings. For instance, when estimating percent cover in small circular area (e.g., within the dripline of a tree), a scale using 25% increments (0-25%, 26-50%, etc.) is typically easy to use and can be rated consistently. For estimating plot canopy cover, canopy dieback, or other quantities that can vary across a wide percentage range, the following 0 to 6 scale is useful:
Rating Percentage range
0 none / not present
1 more than 0 but less than 2.5%
2 2.5% to less than 20%
3 20% to less than 50%
4 50% to less than 80%
5 80% to less than 97.5%
6 97.5% or more
Note that the classes in this scale are not uniform in size and are largest near 50% and smaller near 0 and 100%. Various studies have shown that observers are able to estimate percentages (such as percent cover) that are close to 0 or 100% with greater accuracy than they can estimate percentages near 50%. This makes sense intuitively. For instance, it is easier to distinguish between 2% and 12% cover than it is to distinguish between 45% and 55% cover, even though the absolute difference is 10% cover in either case. The scale above is similar to the Daubenmire (1959) scale except that the class edges have been modified so that the midpoints of the scale increments are equally spaced in an arcsine transformed scale. Percentage data is typically binomially distributed and the arcsine transformation (arcsine of the square root of the percentage expressed as a decimal) is used before this type of data is analyzed using standard parametric statistical tests. By using a pre-transformed scale (Little and Hills 1972), ratings can be statistically analyzed without further transformation.


Seed: Conceal
Illusion (Glamer)
Spellcraft DC: 17
Components: V, S
Casting Time: 1 minute
Range: Personal or touch
Target: You or a creature or object of up to 2,000 lb.
Duration: 200 minutes or until expended (D)
Saving Throw: None or Will negates (harmless, object)
Spell Resistance: No or Yes (harmless, object)
This seed can conceal a creature or object touched from sight, even from darkvision. If the subject is a creature carrying gear, the gear vanishes too, rendering the creature invisible. A spell using the conceal seed ends if the subject attacks any creature. Actions directed at unattended objects do not break the spell, and causing harm indirectly is not an attack. To create invisibility that lasts regardless of the actions of the subject, increase the Spellcraft DC by +4. Alternatively, this seed can conceal the exact location of the subject so that it appears to be about 2 feet away from its true location; this increases the Spellcraft DC by +2. The subject benefits from a 50% miss chance as if it had total concealment. However, unlike actual total concealment, this displacement effect does not prevent enemies from targeting him or her normally. The conceal seed can also be used to block divination spells, spell-like effects, and epic spells developed using the reveal seed; this increases the Spellcraft DC by +6. In all cases where divination magic of any level, including epic level, is employed against the subject of a spell using the conceal seed for this purpose, an opposed caster level check determines which spell works.


text:
It's important to make smart decisions while traveling, including choices that support local communities and protect the environment. Fortunately, there are plenty of sustainable tourism options in Uzbekistan. There are many guesthouses and homestays, especially in smaller villages, where the cost of the stay largely goes towards supporting local families. Check out tours to Aydarkul Lake (with stops at local villages), the Jeyran Ecocenter (home to threatened and endangered species), and sustainable tours to the Aral Sea, where tourism has grown to support villages where the fishing industry has been lost due to the receding waters.
(Visited 17 times, 1 visits today)

source: m-a-p/FineFineWeb


A common question for people starting to program on Windows is, "What makes a valid Windows file name?" You want to use this information to make simplifying assumptions in your code: that names can be no longer than MAX_PATH, that two names won't differ only by case, etc. Unfortunately, the answer to what makes a valid file name in Windows is not simple.
Due to the layering of Windows architecture, the definition of a "legal" file name may vary depending upon the component of the operating system you are dealing with.
· NTFS and the Posix subsystem have the most permissive definition of a "legal" name. The name may be up to 32,768 Unicode characters long. The name can contain trailing periods, trailing spaces, and two files may have names that differ only in case (e.g., README.TXT and readme.txt).
· The Win32 subsystem enforces additional constraints on legal file names. The name can be at most MAX_PATH characters long (defined in windef.h as 260 characters), may not have trailing dots or spaces, and file names are case preserving, not case sensitive — if two files exists with names that differ only in case, you will only be able to manipulate one of them through Win32 APIs.
· DOS and 16-bit Windows applications are still limited to "8.3" names.
See Inside Windows 2000, pages 729ff, for more information on the different constraints on file names.
These differences have practical consequences for any code that attempts to manage files that could be created by another program. If your management code uses DOS (heaven forbid!) or Win32 APIs to manipulate files, it is possible for the untrusted program to create files that your program cannot open or manipulate. For example, a user connected to Posix-based FTP server could create files with file names longer than MAX_PATH. If the administrator uses a Win32-based program to manage the FTP upload directory, then he will not be able to open, delete, or otherwise manipulate the files with long file names.
If you are writing a Win32-based program that manages arbitrary files, consider prepending "\\?\" to the start of file names before you call CreateFile( ), DeleteFile( ), RenameFile( ), etc. This escape sequence at the start of a file name instructs the Win32 subsystem to bypass its normal name checking functions, and you will be able to use any valid NTFS name from your Win32 program.


text:
Introduction to the popular 19th century British artist, £25.00
Explore / Articles
Conserving a statue of Hadrian
The well-known statue of Hadrian dressed as a Greek has long been thought to demonstrate the emperor's love of Greek culture. Preparation for the exhibition Hadrian: Empire and Conflict gave Museum conservators the opportunity to investigate their suspicions that the head did not belong on the body.
It was decided to remove plaster between the neck and the drapery across the statue's shoulders, which had clearly been added since the sculpture was restored. The heavy head was slung into a cradle to secure it while a conservator worked with small chisels and a hammer to gradually remove the plaster fill.
As areas of the original neckline and drapery were revealed it became obvious that the head did not, and could not align correctly with the receiving socket in the body. There was no dowel joining the head to the body, only a bed of plaster. With the head removed, the receiving socket and the tenon (the projection at the base of the neck that inserts into the socket) of Hadrian's head were revealed for the first time in 150 years.
What is particularly unusual is that the head has a wedge-shaped cut in its tenon, and the receiving socket is set in an off-centre square section. In other words, they don't match. This confirmed the theory that the head did not belong to the body, but that the two were put together probably in the nineteenth century.
It was decided to mount the head back on the body in order to explain the history of this sculpture. The join was made so that it could be removed again in the future. Without the plaster fill it is clear that the body and head do not belong together.

source: HuggingFaceFW/fineweb-edu


text:
Many people may look to switch gas and electricity provides to reduce the impact rising prices are having on their household bills, which are having an impact on many families.
A study by Santander revealed 29 per cent of individuals say their overall standard of living has been negatively affected by spiralling costs for everyday essentials.
It found gas bills have almost trebled over the last ten years, while electricity prices climbed by 109 per cent between 2002 and 2012.
However, over the same period, average incomes increased by just 24 per cent, according to data from the Office for National Statistics.
Banking director at Santander Carlos Palacios said this is a situation that is likely to get worse in the future as expenses continue to spiral.
However, he noted: "There are a number of things people can do to reduce their household bills, from installing home energy monitors to analysing their energy usage or changing their utility suppliers."
Recently, a study by Policy Exchange found half of people say reducing energy bills should be a key priority for politicians.
If you want to find out more about switching energy suppliers and how you could save hundreds of pounds in minutes, click here.
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Documentation
Overview
Package bundler is responsible for efficiently transforming aggregate stream data into Butler messages for export.
A process will instantiate a single Bundler instance. The Bundler manages an elastic set of Stream instances, each of which contains state for a single log Stream.
Each Stream instance will have sequential stream binary data appended to it via Append, which it will collect and organize for export as a series of ButlerLogBundle_Entry protobufs. Streams operate independently and buffer data until it is consumed by their Bundler instance. If a Stream's buffer is full, the Stream will block on appending data, which will, in turn, block its data source.
The Bundler owns the various Stream instances. When its Next() method is called, it will sort through the stream instances to prepare an optimally-sized ButlerLogBundle protobuf for export. The construction of this bundle may block pending data, and may be subject to various data urgency requests.
The Bundler acknowledges the following constraints:
- Data enqueued into a Stream should be exported within a specific period
 of time from its introduction
- The exported ButlerLogBundle protobuf must not exceed a maximum bundle
 size constraint.
- Stream data may be added during the bundling process, and should be
 acknowledged if possible.
When a Stream is finished, its Close method should be called. This alerts the Stream that it will receive no more data, causing it to export a terminal ButlerLogBundle and unregister from the Bundler.
The Bundler may block via its CloseAndFinish() method until all Streams are drained and cleared.
Index
Constants
This section is empty.
Variables
This section is empty.
Functions
This section is empty.
Types
type Bundler
type Bundler struct {
 // contains filtered or unexported fields
}
Bundler is the main Bundler instance. It exposes goroutine-safe endpoints for stream registration and bundle consumption.
func New
func New(c Config) *Bundler
New instantiates a new Bundler instance.
func (*Bundler) CloseAndFlush
func (b *Bundler) CloseAndFlush()
CloseAndFlush closes the Bundler, alerting it that no more streams will be added and that existing data may be aggressively output.
CloseAndFlush will block until all buffered data has been consumed.
func (*Bundler) GetStreamDescs
func (b *Bundler) GetStreamDescs() map[string]*logpb.LogStreamDescriptor
GetStreamDescs returns the set of registered stream names mapped to their descriptors.
This is intended for testing purposes. DO NOT modify the resulting descriptors.
func (*Bundler) Next
func (b *Bundler) Next() *logpb.ButlerLogBundle
Next returns the next bundle, blocking until it is available.
func (*Bundler) Register
func (b *Bundler) Register(d *logpb.LogStreamDescriptor) (Stream, error)
Register adds a new stream to the Bundler, returning a reference to the registered stream.
The Bundler takes ownership of the supplied Properties, and may modify them as needed.
type Config
type Config struct {
 // Clock is the clock instance that will be used for Bundler and stream
 // timing.
 Clock clock.Clock
 // MaxBufferedBytes is the maximum number of bytes to buffer in memory per
 // stream.
 MaxBufferedBytes int64
 // MaxBundleSize is the maximum bundle size in bytes that may be generated.
 //
 // If this value is zero, no size constraint will be applied to generated
 // bundles.
 MaxBundleSize int
 // MaxBufferDelay is the maximum amount of time we're willing to buffer
 // bundled data. Other factors can cause the bundle to be sent before this,
 // but it is an upper bound.
 MaxBufferDelay time.Duration
}
Config is the Bundler configuration.
type Data
type Data interface {
 chunkstream.Chunk
 // Bind resizes the Chunk buffer and records a timestamp to associate with the
 // data chunk.
 Bind(int, time.Time) Data
 // Timestamp returns the bound timestamp. This will be zero if no timestamp
 // has been bound.
 Timestamp() time.Time
}
Data is a reusable data buffer that is used by Stream instances to ingest data.
Data is initially an empty buffer. Once data is loaded into it, the buffer is resized to the bound data and a timestamp is attached via Bind.
type Stream
type Stream interface {
 // LeaseData allocates and returns a Data block that stream data can be
 // loaded into. The caller should Release() the Data, or transfer ownership to
 // something that will (e.g., Append()).
 //
 // If the leased data is not Released, it is merely inefficient, not fatal.
 LeaseData() Data
 // Append adds a sequential chunk of data to the Stream. Append may block if
 // the data isn't ready to be consumed.
 //
 // Append takes ownership of the data regardless of whether or not it returns
 // an error. The supplied Data must not be referenced after calling Append.
 Append(Data) error
 // Close closes the Stream, flushing any remaining data.
 Close()
}
Stream is an individual Bundler Stream. Data is added to the Stream as a series of ordered binary chunks.
A Stream is not goroutine-safe.


text:
The tutorial demonstrates analysis of 2D photonic crystal using PWE Band solver.
First we create a lattice model of dielectric cylinders (permittivity=8.9) suspended in air. We then proceed with a simple simulation on a predefined k-vector path and result analysis. Finally we discuss the meaning of the Domain Origin in the PWE dialog box.
1 Create layout of the 2D rectangular photonic crystal lattice
2 Set Parameters of PWE Band Solver
3 Simulation Run and Results Analysis
4 Using Inversion Symmetry and Domain Origin
5 2D Hexagonal lattice
6 Band solving of rotated lattices


text:
Malyshev O. V., Eyduk V. I., Kudryavtsev D. N.
The present article aims at estimation of creating a mathematical model for urgent predicting the parameters of a bottom hydrodynamic pressure noise in coastal waters in depending on the spectrum of moderate surface waves. The proportions of estimating hydrodynamic pressure spectra, as a result of turbulence in dependence on its spectral composition are given. It is shown that average pressure spectra is close to «−2» power law and at the absence of significant surface waves pressure spectrum noise is corresponding to the turbulence with the dissipation rate ε ≈ 10-6–10-5 m2⁄s3. For the moderate surface waves conditions regression of turbulent pressure level dependence of the wave spectrum peak magnitude and frequency have been obtained. Regression of low-frequency level of the spectrum wave dependence of the wave spectrum peak magnitude has also been obtained. The data of the low-frequency level of the part of the surface wave spectrum don't contradict to the Firsov—Rakhmanin model. The mathematical model of hydrodynamic bottom pressure spectra depending on the parameters of the wave spectrum and estimation of model coefficients are proposed. The model takes into account turbulence noise, low-frequency wave noise and «area of the maximum» wave noise. The average difference between predicted and experimental values for the full sample of data is close to 4 dB. Identification of variability of model coefficients under different hydrophysical conditions requires further systematic agreed measurements of surface waves and bottom pressure noise in water areas of practical interest.


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The rtc skippatch command excludes load objects, object files and functions from being instrumented by runtime checking. The effect of the command is permanent to each dbx session unless the load object is unloaded explicitly.
Since dbx does not track memory access in load objects, object files, and functions affected by this command, incorrect rui errors might be reported for functions that were not skipped. dbx cannot determine whether an rui error was introduced by this command, so such an error was not suppressed automatically.
Exclude the specified load objects from being instrumented.
Exclude the specified object files and functions in the specified load object from being instrumented.
load_object is the name of a load object or the path to the name of a load object.
object_file is the name of an object file.
function is the name of a function.


Künneth theorem
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In mathematics, especially in homological algebra and algebraic topology, a Künneth theorem, also called a Künneth formula, is a statement relating the homology of two objects to the homology of their product. The classical statement of the Künneth theorem relates the singular homology of two topological spaces X and Y and their product space X × Y. In the simplest possible case the relationship is that of a tensor product, but for applications it is very often necessary to apply certain tools of homological algebra to express the answer.
A Künneth theorem or Künneth formula is true in many different homology and cohomology theories, and the name has become generic. These many results are named for the German mathematician Hermann Künneth.
Singular homology with coefficients in a field[edit]
Let X and Y be two topological spaces. In general one uses singular homology; but if X and Y happen to be CW complexes, then this can be replaced by cellular homology, because that is isomorphic to singular homology. The simplest case is when the coefficient ring for homology is a field F. In this situation, the Künneth theorem (for singular homology) states that for any integer k,
\bigoplus_{i + j = k} H_i(X; F) \otimes H_j(Y; F) \cong H_k(X \times Y; F).
Furthermore, the isomorphism is a natural isomorphism. The map from the sum to the homology group of the product is called the cross product. More precisely, there is a cross product operation by which an i-cycle on X and a j-cycle on Y can be combined to create an (i+j)-cycle on X × Y; so that there is an explicit linear mapping defined from the direct sum to Hk(X × Y).
A consequence of this result is that the Betti numbers, the dimensions of the homology with Q coefficients, of X × Y can be determined from those of X and Y. If pZ(t) is the generating function of the sequence of Betti numbers bk(Z) of a space Z, then
p_{X \times Y}(t) = p_X(t) p_Y(t).
Here when there are finitely many Betti numbers of X and Y, each of which is a natural number rather than ∞, this reads as an identity on Poincaré polynomials. In the general case these are formal power series with possibly infinite coefficients, and have to be interpreted accordingly. Furthermore, the above statement holds not only for the Betti numbers but also for the generating functions of the dimensions of the homology over any field. (If the integer homology is not torsion-free then these numbers may differ from the standard Betti numbers.)
Singular homology with coefficients in a principal ideal domain[edit]
The above formula is simple because vector spaces over a field have very restricted behavior. As the coefficient ring becomes more general, the relationship becomes more complicated. The next simplest case is the case when the coefficient ring is a principal ideal domain. This case is particularly important because the integers Z are a PID.
In this case the equation above is no longer always true. A correction factor appears to account for the possibility of torsion phenomena. This correction factor is expressed in terms of the Tor functor, the first derived functor of the tensor product.
When R is a PID, then the correct statement of the Künneth theorem is that for any topological spaces X and Y there are natural short exact sequences
0 \to \bigoplus_{i + j = k} H_i(X; R) \otimes_R H_j(Y; R) \to H_k(X \times Y; R) \to \bigoplus_{i + j = k-1} \mathrm{Tor}_1^R(H_i(X; R), H_j(Y; R)) \to 0.
Furthermore these sequences split, but not canonically.
The short exact sequences just described can easily be used to compute the homology groups with integer coefficients of the product P2(R) × P2(R) of two real projective planes, in other words Hk(P2(R) × P2(R); Z). These spaces are CW complexes. Denoting the homology group Hi(P2(R); Z) by hi for brevity's sake, one knows from a simple calculation with cellular homology that
hi = 0 for all other values of i.
The only non-zero Tor group (torsion product) which can be formed from these values of hi is
\mathrm{Tor}^{\mathbf{Z}}_1(h_1, h_1) \cong \mathrm{Tor}^{\mathbf{Z}}_1(\mathbf{Z}/(2),\mathbf{Z}/(2))\cong \mathbf{Z}/(2).
Therefore the Künneth short exact sequence reduces in every degree to an isomorphism, because there is a zero group in each case on either the left or the right side in the sequence. The result is
H_0 \left (\mathbf{P}^2(\mathbf{R}) \times \mathbf{P}^2(\mathbf{R});\mathbf{Z} \right )\; &\cong \;h_0 \otimes h_0 \;\cong \;\mathbf{Z} \\
H_1 \left (\mathbf{P}^2(\mathbf{R}) \times \mathbf{P}^2(\mathbf{R});\mathbf{Z} \right )\; &\cong \; h_0 \otimes h_1 \; \oplus \; h_1 \otimes h_0 \;\cong \;\mathbf{Z}/(2)\oplus \mathbf{Z}/(2) \\
H_2 \left (\mathbf{P}^2(\mathbf{R}) \times \mathbf{P}^2(\mathbf{R});\mathbf{Z} \right )\; &\cong \;h_1 \otimes h_1 \;\cong \;\mathbf{Z}/(2) \\
H_3 \left (\mathbf{P}^2(\mathbf{R}) \times \mathbf{P}^2(\mathbf{R});\mathbf{Z} \right )\; &\cong \;\mathrm{Tor}^{\mathbf{Z}}_1(h_1,h_1) \;\cong \;\mathbf{Z}/(2) \\
and all the other homology groups are zero.
The Künneth spectral sequence[edit]
For a general commutative ring R, the homology of X and Y is related to the homology of their product by a Künneth spectral sequence
E_{pq}^2 = \bigoplus_{q_1 + q_2 = q} \mathrm{Tor}^R_p(H_{q_1}(X; R), H_{q_2}(Y; R)) \Rightarrow H_{p+q}(X \times Y; R).
In the cases described above, this spectral sequence collapses to give an isomorphism or a short exact sequence.
Relation with homological algebra, and idea of proof[edit]
The chain complex of the space X × Y is related to the chain complexes of X and Y by a natural quasi-isomorphism
C_*(X \times Y) \cong C_*(X) \otimes C_*(Y).
For singular chains this is the theorem of Eilenberg and Zilber. For cellular chains on CW complexes, it is a straightforward isomorphism. Then the homology of the tensor product on the right is given by the spectral Künneth formula of homological algebra.[1]
The freeness of the chain modules means that in this geometric case it is not necessary to use any hyperhomology or total derived tensor product.
There are analogues of the above statements for singular cohomology and sheaf cohomology. For sheaf cohomology on an algebraic variety, Grothendieck found six spectral sequences relating the possible hyperhomology groups of two chain complexes of sheaves and the hyperhomology groups of their tensor product.[2]
Künneth theorems in generalized homology and cohomology theories[edit]
There are many generalized or extraordinary homology and cohomology theories for topological spaces. K-theory and cobordism are the best-known. Their striking common feature (not their definition) is that they do not arise from ordinary chain complexes. Thus Künneth theorems can not be obtained by the above methods of homological algebra. Nevertheless Künneth theorems in just the same form have been proved in very many cases by various other methods. The first were Atiyah's Künneth theorem for complex K-theory and Conner and Floyd's result in cobordism.[3][4] A general method of proof emerged, based upon a homotopical theory of modules over highly structured ring spectra.[5] The homotopy category of such modules closely resembles the derived categories of homological algebra.
 1. ^ See final chapter of Mac Lane, Saunders (1963), Homology, Berlin: Springer, ISBN 0-387-038


text:
- Today : Moderate levels of air pollution are expected across central and eastern parts of England due to light winds, Low levels of pollution are expected to prevail across the rest of the UK.
- Tomorrow : Low levels of pollution are expected across the UK, with locally elevated areas of air pollution in the East of England.
- Outlook : Low levels of air pollution are expected.
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text:
The second ever praseodymium compound with a +5 oxidation state paves the way for pentavalent lanthanide chemistry
The first pentavalent praseodymium nitride–oxide that features a rare Pr≡N triple bond is the second ever lanthanide(V) complex to be made.1
Lanthanide chemistry is dominated by the +3 oxidation state. There are some common +4 lanthanide complexes such as cerium oxide (CeO2), but +5 compounds have proven elusive. Praseodymium has long been considered as the most promising route to lanthanide(V) chemistry as it has five valence electrons, but the first pentavalent praseodymium complex, the oxide PrO2+, was only synthesised last year.2
Now, a team led by Mingfei Zhou from Fudan University and Jun Li Tsinghua University, China, reacted individual praseodymium atoms with nitric oxide in a solid neon matrix at 4K (–269.15°C) to create the second ever lanthanide(V) compound, NPrO. The compound was detected using infrared spectroscopy.
Calculations show that its linear structure optimises the overlap of the praseodymium atom's 5d and 4f orbitals with the nitrogen and oxygen orbitals. The 5d orbitals stabilise praseodymium's high oxidation state – just as in PrO2+.
The participation of the contracted lanthanide 4f orbitals in covalent bonds is extremely rare and this research shows that higher oxidation state lanthanide chemistry could be richer than previously believed.


Intermittent poor performance when the MDB's are getting messages from MQ queues
Technote (troubleshooting)
You have MDB's driven by messages from WebSphere MQ queues. Intermittently the MDB's experience a delay where it may take up to sixteen seconds for the retrieval of each message. There is no gradual degradation. The MDB's are running fine one minute, then they will experience these delays and then resume normal processing. The MDB's will usually only experience these delays for a short time, usually 30 seconds or less, before they start retrieving messages in a matter of a few milliseconds again.
A review of MQ and MQ JMS traces at the time of the delays reveals that the messages were on the queue and available at the time when the MDB's were experiencing a delay. The MDB's are doing a browse of the messages prior to doing a MQGET to remove the message from the queue. The delayed messages have a priority of 5 in the MQ message descriptor (MQMD) while most of the messages being browsed have a priority 0 or 4, which are lower priorities.
The observed delay is that the thread which is doing MQGET is using the MQGMO_BROWSE_NEXT option and it has browsed to a later point in the queue than the point where the priority 5 messages were committed. Each browsing thread from the MDB's has a browse cursor whose position in the queue dictates the next message that thread is able to get. Messages committed to the queue before the browse cursor's current position are not gettable by that thread until it issues a new MQGET call using the MQGMO_BROWSE_FIRST option. The browse cursor is then reset to point at the start of the queue and therefore the higher priority messages are now visible to the browsing thread.
The delayed messages are successfully delivered after the browse thread uses MQGMO_BROWSE_FIRST. The time delay is accounted for by the application making MQGMO_BROWSE_NEXT + MQGMO_WAIT calls at a time when the browse cursor has moved past the priority 5 messages.
Here is an example to illustrate the concept of how a browse cursor works and why these delays are occurring. Suppose that a priority queue contains the following sequence of messages:
Message A priority 4
Message B priority 4
Message C priority 3
Message B was put onto the queue after Message A, hence why it appears second. Messages at the same priority are stored in arrival sequence. Now suppose the queue is opened by a single application which then issues a get with MQGMO_BROWSE_FIRST. The application's browse cursor is pointed at Message A and MQ returns a copy of Message A in the application buffer. Since this was a browse call, Message A remains on the queue.
The queue now looks like this:
Message A priority 4 <-- application browse cursor
Message B priority 4
Message C priority 3
Now suppose that a second application opens the queue for output and puts a new message (D) onto the queue at priority 5. In an MQ priority queue, 5 is a higher priority than 4 so this message is added at the start of the queue.
The queue now looks like this:
Message D priority 5
Message A priority 4 <-- application browse cursor
Message B priority 4
Message C priority 3
When the browsing application issues its next get with MQGMO_BROWSE_NEXT then its browse cursor moves down to the next message on the queue after the current position and the application is given a copy of Message B.
The queue now looks like this:
Message D priority 5
Message A priority 4
Message B priority 4 <-- application browse cursor
Message C priority 3
Even though Message D is earlier in the queue and has not been seen by the application yet, the design of MQGMO_BROWSE_NEXT is to move down to the next message in the queue. The browse continues in this manner until the browsing application reaches the end of the queue. At this point, the application receives reason code 2033 (MQRC_NO_MSG_AVAILABLE) and therefore knows it has reached the end. So it then issues a get with MQGMO_BROWSE_FIRST again, which resets the browse cursor to the top of the queue and so now it will get a copy of Message D.
The performance delay in this case was accounted for by the time it took to browse the remainder of the queue before re-issuing a get with the MQGMO_BROWSE_FIRST option. During that time, the higher priority message sat at the top of the queue without being processed until the browse first call was issued.
Resolving the problem
There are various strategies for handling the situation differently, and so avoiding the symptom.
One simple option is to change the queue to be a First In First Out (FIFO) queue. You can do this using runmqsc to "ALTER QLOCAL(QNAME) MSGDLVSQ(FIFO)". This would cause messages to be delivered in arrival sequence instead of priority.
From an application server perspective, there are a couple of options available to help ensure messages are processed in a more timely manner.
1. Reconfigure the application server to use non-ASF mode. Using non-ASF mode changes the mechanism that the application server uses to get messages so that, rather than performing a browse of the queue, it simply issues MQGET calls. This means that MDB's will always be given the message that is currently at the top of the queue. More details about non-ASF mode, including how to configure the application server to use this mode of operation, can be found in the following developerWorks article titled "When to use ASF and non-ASF modes to process messages in WebSphere Application Server".
2. Change the custom property eoqtimeout. When scanning the queue for a message, once the queue agent reaches the end of the queue, this is the length of time it waits before going back to the top of the queue and beginning a new scan. Information about how to change this timeout value can be found in the technote titled "How to modify the Generic JVM Arguments and Java system properties for a WAS server".
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text:
Aboriginal associations with the park area
Barrington Tops National Park and State Conservation Area overlie the territories of several Aboriginal groups:
- the eastern side is the traditional country of the Worimi and Biripi people
- the southern valleys were occupied by the Gringai clan of the Worimi people
- the western side is Wonnarua country.
The Biripi took in the area between Tuncurry, Taree and Gloucester. Worimi territory extended from Barrington Tops and Forster in the north to Maitland and the Hunter River in the south.
The Worimi, Biripi and Wonnarua were divided into a number of nurras or clans. Nurras were local groups within tribes, each occupying a definite part of the tribal territory. Both the Worimi and Biripi spoke the Kattang language.
Aboriginal people were hunters and gatherers who moved throughout their territory in response to the seasonal availability of food. This meant that the land's resources were naturally replenished.
Clans occupied the valleys year round, visiting the plateaus in spring and summer to gather food. The coastal clans would move to the tops during winter to hunt kangaroos, possums and wombats.
A wide range of plant foods was collected from the lowland forests. The edible fruits found in the Barrington Tops area include:
- orange thorn
- giant stinging tree
- native cherry
- native raspberry
Other traditional plant foods include the bulbs of many orchids and the starch from the crown of tree ferns. There is also a report of starch from stinging tree roots being roasted to make a bread.
When Europeans settled in the Gloucester-Manning area in the 1820s and 1830s, the Aboriginal people lost their homelands to logging, clearing and livestock. Traditional hunting grounds were depleted, and sacred sites were destroyed. Wildlife dwindled. Oral history tells us that by 1840 the natural food supplies were almost exhausted.
Starving Aboriginal people began killing stock. The settlers and government troopers retaliated with random shootings and massacres. Around the Manning River basin, there were reports of waterholes and 'gifts' of food being laced with arsenic, known as 'the Harmony'.
The rugged lands of the Barrington Tops sometimes became a refuge for Aboriginal people, most famously for black outlaw Jimmy Governor.
Today, Barrington Tops National Park and State Conservation Area are important to today's Worimi, Biripi and Wonnarua communities, as an intact part of Aboriginal country.
Aboriginal sites in the park
The Aboriginal occupation of Barrington Tops is recorded in oral history, and in the presence of Aboriginal sites. Sites in the park include:
- open campsites with stone artefacts
- scarred trees
- ceremonial places
- mythological sites recorded in dreaming stories.
The Barrington Tops after colonisation
After government surveyors had explored the Barrington Tops area, 19th-century interest was limited to timbergetting, a little gold exploration, and summer grazing on the tops. At the turn of the 20th century, several large state forests were proclaimed. In 1905, grazier W.H. Edwards built a hut on Edwards Plain which later became a haven for adventurers, naturalists and holidaymakers.
Through the early 20th century, groups of gentlemen made their way to the tops for riding, hunting and fishing holidays. They approached on a bridle trail up The Corker or from the north. Scientific parties soon followed, attracted to the rich variety of landscapes, plants and animals. In 1915, a large expedition of geologists, botanists and entomologists camped at Edwards Hut and collected specimens.
Word of the Barrington Tops' delights spread quickly. In the early 1920s, there was talk of agriculture and a racecourse, golf course, and hydroelectric development. After heavy snow on the plateau in 1923, it was suggested that the area could be a wonderful playground for skiing and skating. In 1934, Newcastle City Council drew up a detailed plan for a tourist resort on the plateau. But road access up the steep southern slope of the plateau proved too difficult, and all the grand plans came to nothing.
The history of the park
Conservationist Myles Dunphy took a long walk over the tops with the Mountain Trails Club in the summer of 1924-5. He suggested a national park 'or better still, a primitive reserve' as an alternative to development. There were protests over logging and roadbuilding, even during World War II.
Through the 1950s, pressure for a national park grew - though others were pushing for more development. In 1959, the government decided to set aside two small areas, one on Gloucester Tops and the other in the Williams River area. The state forest system was also expanded. Finally, in 1969 Barrington Tops National Park was created from around 14,000 hectares of Crown land. Barrington Tops State Conservation Area was created in 2000.
From the 1970s to the 1990s, an intense community debate developed over whether the remaining native forests of NSW should be used for timber production or protected for conservation. Forest areas were progressively withdrawn from logging and added to the national park system. The rainforests were protected first, then the eucalypt forests.
The park was enlarged by major additions in 1984, 1997 and 1999. It was listed as World Heritage in 1986, and the Barrington Wilderness was declared in 1999.


text:
Marian Anderson's brilliant singing career began at age six when she sang spirituals at the Union Baptist Church in her hometown of Philadelphia. She toured Europe in the 1920s, drawing vast acclaim; however, when she returned to the United States she was still barred from performing 5 on the American operatic stage. After she was prevented from singing in Washington's segregated Constitution Hall in 1939, Eleanor Roosevelt intervened and arranged for Miss Anderson to perform at the Lincoln Memorial. A crowd of 75,000 people came to watch her sing before the Memorial. Marian Anderson's beautiful contralto voice broke down 10 racial barriers, showing white Americans that blacks had a profound contribution to make to America's cultural life. Eventually, in 1955, she became the first AfricanAmerican singer to perform at New York's Metropolitan Opera. In her many years of touring she had to endure a racism that forced her to enter concert halls and hotels through 15 service entrances. Her grace under this stress showed a moral perseverance that paralleled that of the famous Martin Luther King, Jr.
1. We can conclude from the passage that Marian Anderson first toured Europe instead of the United States because
2. The word "vast" in line 3 could best be replaced by which of the following?
3. The word "barred" in line 4 could best be replaced by which of the following?
4. The significance of Anderson's Lincoln Memorial performance was that
5. In line 7, the word "intervened" means that Eleanor Roosevelt
6. In line 9-10, the phrase "broke down... barriers" means
7. In line 10, the word "profound" could best be replaced by
8. The word "eventually" in line 11 could best be replaced by which of the following?
9. The word "grace" in line 15 is similar in meaning to which of the following?
10. According to the passage, what did Marian Anderson have in common with Martin Luther King, Jr?
11. The author's tone in this passage is
12. In line 15, what does the word "this" refer to?
Đề thi ViOlympic Lớp 12 Trên Mạng có thể tìm thấy tại đây.


text:
Maputo — The rate of inflation in Mozambique in February, as measured by the consumer price indices for the three largest cities (Maputo, Nampula and Beira), was 0.39 per cent, the National Statistics Institute (INE) announced on Friday.
This is a decline on the January inflation rate which was 0.98 percent, and it is a much lower rate than in February 2013, when prices rose by 1.16 per cent.
Most of the significant February price rises were for foodstuffs. The rises which had most impact on the consumer price index were for tomatoes (15.4 per cent), cabbage (12.4 per cent), lettuce (14.2 per cent), and coconuts (2.7 per cent). Between them these four products pushed the overall level of prices up by 0.47 per cent. Tomatoes alone were responsible for pushing the consumer price index up by 0.32 per cent.
On the other hand, several key foods fell in price - the price of cassava flour declined by 6.7 per cent, while potatoes and onions were 4.4 per cent and 1.5 per cent cheaper respectively.
The accumulated inflation so far this year is 1.37 per cent. At the same time in 2013, it was 2.52 per cent.
Comparing prices this February with prices in February 2013, the increase has been 2.38 per cent.
The average 12 monthly inflation rate over the past year was 4.14 per cent - down from 4.29 per cent in January.
There were significant differences in the inflation rate between the three cities. Maputo saw the sharpest price rises in February, of 0.66 per cent, while in Beira and Nampula price rises were minimal. In Nampula the consumer price index rose by 0.13 per cent, and in Beira by 0.11 per cent.
But when the entire past year is taken into consideration, Nampula had the highest inflation rate of the three cities, at 3.43 per cent, followed by Maputo with 2.26 per cent. In Beira, however, prices only rose by 0.63 per cent.


text:
Our annual gathering, STEMxChange, is coming up in just a few weeks. Today, we're announcing a new keynote. We'll also detail the sessions that will make up the STEMx track.
Our second keynote will be…Astronaut Joe Acaba! Joining Grant Imahara, he'll address both STEMxChange and the Tennessee STEM Innovation Summit. Just over a month ago, Acaba was completing a fiery descent through the atmosphere down to Earth. This descent marked the end of Acaba's third mission for NASA. Most recently, he spent 168 days working in the International Space Station. Acaba joined astronaut Mark T. Vande Hei in a year-long NASA push to engage classrooms with the space station. Acaba brings a special perspective. Before joining NASA, he served five years as a teacher in Florida.
We're also deeply proud to announce eight different sessions from STEMx member states. From Idaho to South Carolina, STEM schools to manufacturing, you're sure to find something to help you make the most out of your dedication to effective STEM education. Read about all of the STEMx sessions below. Attendees will also have complete access to another 32 sessions organized by the Tennessee STEM Innovation Network.
Register now while spots remain! Details: _URL_
Joseph M. Acaba NASA Astronaut
Acaba was selected by NASA in 2004. The California native has logged a total of 306 days in space during three missions. Most recently, Acaba served as Flight Engineer on the International Space Station for Expedition 53/54, landing back on Earth on February 28, 2018. Prior to arriving at NASA, Acaba taught middle and high school math and science.
STS-119 (March 15 to March 28, 2009). This was the 125th shuttle flight, the 36th flight of Discovery and the 28th shuttle flight to the International Space Station. The primary objective of this flight was to deliver the final pair of power-generating solar array wings and truss element to the International Space Station. Acaba accumulated 12 hours and 57 minutes of Extravehicular Activity (EVA) in two spacewalks. STS-119 returned to land at the Kennedy Space Center, having traveled 202 orbits and 5.3 million statute miles in 12 days, 19 hours and 29 minutes.
Expedition 31/32 (May 15 through September 17, 2012). Acaba launched on May 15, 2012, from the Baikonur Cosmodrome in Kazakhstan. Gennady Padalka and Sergei Revin of the Russian Federal Space Agency and Acaba landed their Soyuz TMA-04M spacecraft in Kazakhstan on September 17, 2012. Acaba spent 123 days aboard the station as a Flight Engineer of the Expedition 31 and 32 crews. Acaba supported the arrival of the first commercial resupply spacecraft, SpaceX's Dragon, in late May; and was prime robotic arm operator for the capture and release of the third Japanese cargo ship, HTV3. Acaba served as intra-vehicular crew member and robotic arm operator for two U.S.-based spacewalks, helping to restore a critical power unit and exchange a faulty camera on the station's robotic arm. Acaba also participated in numerous scientific research experiments and performed regular maintenance and operational tasks aboard the orbiting complex.
Expedition 53/54 (September 13 through February 28, 2018). The crew launched from the Baikonur Cosmodrome aboard the Soyuz spacecraft. Acaba, who served as Flight Engineer, was joined by Astronaut Mark Vande Hei and Russian Cosmonaut Alexander Misurkin of Roscosmos. During the mission the crew marked the beginning of the first long-term increase in crew size on the U.S. segment, enabling NASA to double the time dedicated to research and achieve a record-setting week of research that surpassed 100 hours. Highlights from this research include investigations into the manufacturing of fiber optic filaments in microgravity, improving the accuracy of an implantable glucoses biosensor, and measuring the Sun's energy input to Earth. Acaba completed one spacewalk to lubricate an end effector and install new cameras on the station's arm and truss.
STEMx sessions at STEMxChange/Tennessee STEM Innovation Summit
|STEMx Challenge Grants Panel
|Moderated by Regina Schofield
|Battelle and STEMx Challenge Grant winners||Last Fall, we launched the STEMx Challenge Grant Program to provides STEMx states with up to $15,000 to develop solutions to pressing STEM education issues. Join STEMx state leaders to learn how the program coalesced partners around solving a pressing state issue.|
|Taking on the STEM Grand Challenges: What might you learn from South Carolina's approach?||Grace Doramus, Tom Peters, and Susie Teague||South Carolina Coalition for Mathematics and Science with 100kin10||
Join our session to learn how to take Grand Challenges from daunting to actionable and apply this innovative approach to move the needle against the STEM challenges in your state!
|Using Collaboration to Build Capacity and Increase STEM Engagement
|Karen Peterson and Erin Hogeboom
|National Girls Collaborative Project
|Come learn about the National Girls Collaborative Project (NGCP), a model for sustainable collaboration among cross-sector stakeholders. Participants will engage in hands-on activities designed to facilitate collaboration and leverage resources and expertise, learn about current research on the importance of collaboration, and be introduced to the free tools available from the National Girls Collaborative.|
|Roadmap to Tennessee STEM School Designation||Brandi Stroecker and Sandy Watkins||Tennessee STEM Innovation Network||Tennessee STEM School Designation was developed to provide a "roadmap" for schools to successfully implement a STEM education plan at the local level. The tools and resources created define the attributes necessary for a school, regardless of location, to create a comprehensive STEM learning environment for its students. Learn more about the process to become a designated Tennessee STEM School, recognized by the Tennessee Department of Education.|
|Computer Science: Becoming the Focus of STEM
|Anthony Owen and Scott Smith||Arkansas Department of Education, Arkansas Public School Resource Center||Through the bipartisan actions of the General Assembly and Governor, Arkansas led the nation by being the first state to offer computer science in every high school. The state is continuing to refine and implement a successful statewide CS initiative that is being replicated in other states. In this session, participants will learn how effective partnerships can support building an effective state K-12 CS initiative.|
|MakerMinded for STEM Career Awareness
|Heather Sherman||Ohio STEM Learning Network||MakerMinded is a free program designed to help students learn about opportunities in fields they may not have considered before, like advanced-manufacturing and explore them through site visits, and hands on activities. MakerMinded has been engaging students in TN, OH, KY and MI. In this session, learn about MakerMinded's success across states, and hear about opportunities to bring this program to your state through a new funding opportunity coordinated by STEMx.|
|The Tennessee Rural STEM Collaborative||Brandi Stroecker and Evan Curran||Tennessee STEM Innovation Network
|Interested in place-based education? Hear how the Tennessee Rural STEM Collaborative leverages PBE to increase rural educator's capacity to connect with valuable expertise and access assets that focus on STEM locally. Join us to hear from current Collaborative members and how you can become involved!|
|How Public Private Partnerships are Changing the Landscape of STEM in Idaho||Angela Hemmingway and Anne Seifert||Idaho STEM Action Center,
Idaho National Laboratory
|This interactive session will highlight successful approaches to STEM partnerships including providing mentorship and volunteer opportunities to serve in K-12 schools and out-of-school programs, expanding work-based experiential learning programs, expanding STEM and CS camps, competitions, and family events.|


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Is there a standard or common way to write scientific notation in different bases that doesn't require repeating the base in both the coefficient and the exponent base?
For example, this notation is correct, but is quite verbose:
 - Implicit base 10: $100 \cdot \tau = 6.283 \times 10^2$
 - Explicit base 10: $100 \cdot \tau = 6.283_{10} \times 10_{10}^2$
 - Explicit base 16: $100 \cdot \tau = 2.745_{16} \times 10_{16}^2$
Most calculators & programming languages shorten this to an "exponent" notation such as:
Some rare ones even support a base, such as:
Unfortunately, these are not very nice notations outside of specific domains.
Ideally, I'm looking for an operator notation that concisely does the function:
 - $f(coefficient_{b},exponent) = coefficient_{b} \times b^{exponent}$
If there is no such standard or common notation, I'd be happy to hear any suggestions.
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How about "$\tau = 2.745 \times 10^2$ in base $16$" (or "τ = 2.745e2 in base 16", whichever you prefer)? – ShreevatsaR Jun 5 '11 at 22:42
what's a bit ugly is that you're still using base 10 to denote the base you're using. Maybe, in a way, it's more natural to denote your base by the highest number below the radix, instead of the radix itself, so you'd have base 9 or base F instead of base 10 or base 16 in'metabase' 10. – gfes Jun 5 '11 at 23:03
_USER_ I think your (base-1) notation has some appeal, but using 10 as the "metabase" seems to be the only way I've ever seen it done, and seems to be universally understood. "Base F" immediately makes one think of hexadecimal, but I think if you wrote "base 9" it would be confusing! – wjl Jun 5 '11 at 23:33
True. Although when working in base 10, probably anyone would omit the base 9 / base 10 altogether anyway. Also, I thought of a neater, but less practical way, namely writing the alternative expansion for the radix. I.e. 9._PHONE_ etc. or F.FFFFFFFFF etc. – gfes Jun 5 '11 at 23:37
_USER_ The alternate expansion is quite clever. It would work especially well with an overbar to indicate a the repeating fractional part. – wjl Jun 5 '11 at 23:43
1 Answer 1
Unfortunately, $2.546_{16}\times 10_{16}^{23}$ is cumbersome, and it isn't immediately clear if the exponent is being written in base $10$ or base $16$, and $2.546_{16}\times 16^{23}$ has a strange mixing of base $10$ and base $16$ elements. For programming things, there are explicit prefixes you can put on a number to denote whether it is base $2,8,10$ or $16$, but that isn't general, and it still doesn't really address any of the previous problems.
Maybe a notation like $(2.546\times b^{23})_{16}$ would work to indicate that everything is supposed to be taken base $16$, with $b$ being implicit for the base (as writing either 10 or the base 10 expression of the base is awkward). However, I'm not fully enamored with this notation either.
What is your application of this? In what circumstances is some sort of scientific notation required but base $10$ is undesirable?
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I actually like the parenthesized notation better than anything else I've seen or thought of so far. As far as the application, this is more of a general question that has bugged me for a long time. However, this comes up a lot for me specifically because I often write up detailed mathematical descriptions of the behavior of low-level, digitial electrical engineering applications. For instance, one place a concise notation would be obviously handy is when writing things about DSP algorithms using IEEE floating point in hexadecimal. – wjl Jun 5 '11 at 23:38
Um, one possibility is also to use the shift operators a la C/C++. So $(2.546 \ll 23)_{16}$? – Willie Wong Jul 5 '11 at 23:47
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text:
|North Male atoll Image credit: By rolando000 CC-BY, via flickr|
1. Manta Point
Mantas are the super-order of cartilaginous fish resembling sharks. They are rays with a peculiar body shape having diffused pectoral fins and a slit gill from the ventral part. These little fishes are good cleaning agents as they remove each and every small parasite and other particles from their neighborhood. Manta point is also called as cleaning station that is in the southeast of North Male Atoll.
2. Banana Reef
This popular reef is a reserve of caves with glass fish and soft corals. Several kinds of sea fish such as angel fish, eagle rays, puffers and others splash in this banana-shaped reef.
Octopus and several kinds of sharks also roam freely in this atoll. Only diving experts can explore this pelagic world as too much caution is required. November-May is considered as the best season for diving as currents may develop producing crystal-clear water.
|Surfing site: Image credit: By Ibrahim Asad's PHotography, CC-BY via flickr|
2. Pasta Point : This consistent break amuses the surfers by transforming small waves into a big swell.
3. Jailbreak : The fastest wave formation with long walls and volume is observed in this break point.
4. Sultans: High peak takeoff waves are spotted in this point lying near to the Tari Village Resort.
5. Male Island Point: A dry reef makes Male Island Point, a unique surfing point.
North Male atoll greeting cardsBuy from Amazon
Related posts in Hubpages:
1. Maldives; the tourist's destination in winter
2. Kerala tourism; green rolling hillocks of Vagamon


text:
Volley passes and concentration
Aim - To improve players concentration, touch and confidence in passing on the volley. To have fun and to test the players ability.
- 1. Concentration, watch the ball on to the foot for a clean connection.
- 2. Let the players have some fun with this but do not let the session turn into mayhem, there is a lot to be gained from this work.
- 3. Softness in the first touch.
- 4. Confidence in the volley, don't be afraid or hesitant.
- 5. Aim to get height on the volleys so it's easier for team mate to adjust.


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Objective: To estimate gestational diabetes mellitus (GDM) prevalence and hyperglycemia in a large multi-ethnic population and evaluate the differences in glucose measures by age and ethnicity.
Participants and setting: All singleton births in Kaiser Permanente Hawaii (KPH) during _PHONE_.
Measurements: Ethnicity classifications from birth certificate data were linked to KPH's electronic medical records that included laboratory-screening results. GDM screening was performed using the 50-g, 1-hour oral glucose challenge test (CCT) and the 100-g, 3-hour oral glucose tolerance test (OCTT). GDM was ascertained by both the National Diabetes Data Group (NDDG) and the Carpenter and Coustan (C&C) thresholds.
Results: 21,130 (96%) of all pregnant women were screened for GDM using the 1-hour GCT: 21% had glucose levels exceeding the threshold of 140 mg/dL, with the highest rates in Filipinos and Chinese. African American and Caucasian groups had the lowest elevated glucose. Of those with elevated glucose, 1.3% had levels >200 mg/dL, were considered to have GDM, and not tested further; 88% underwent the 3-hour OGTT. Age-adjusted GDM prevalence was 4.4% (NDDG) and 6.6% (C&C). Koreans (6.2%) and Filipinos (6.1%) had the highest age-adjusted NDDGC GDM. African Americans (1.5%), Caucasians (2.5%), and Vietnamese (2.8%) had the lowest.
Conclusions: This is the first population-based study to report GDM prevalence in a large group of ethnicities represented in Hawaii. We found very diverse rates of GDM prevalence and elevated glucose among these groups. These findings point to the need for further research along several avenues, such as maternal-child outcome differences and perhaps ethnic-specific guidelines for GDM diagnosis.


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Paul Adelburt Bigsby (1899–1968) was an American inventor, designer, and pioneer of the solid body electric guitar. Bigsby is best known for having been the designer of the Bigsby vibrato tailpiece (also mislabeled as a tremolo arm) and proprietor of Bigsby Electric Guitars. He built an early steel guitar for Southern California steel guitarist Earl "Joaquin" Murphy of Spade Cooley's band, as well as Jack Rivers, then built a solid body electric guitar conceptualized by Merle Travis to have the same level of sustain as a steel guitar by anchoring the strings in the body instead of on a tailpiece. This instrument, which Bigsby completed in 1948, likely had an influence on the solid body Telecaster later produced by Leo Fender, as it had all six tuners in a row. Its headstock shape was later made famous by Fender's solid body Stratocaster model. Bigsby also made a doubleneck model for Nashville guitarist Grady Martin and an amplified mandolin for Texas Playboy Tiny Moore. Bigsby also built a pedal steel guitar for Speedy West that West used on many of Tennessee Ernie Ford's early recordings as well as records by Travis, Red Ingle, Jean Shepard, Johnny Horton, Ferlin Husky and Merrill Moore.
Before working in music he was a motorcycle racer known as "P.A. Bigsby", and was the foreman of Crocker Motorcycles, and designed many components, such as the overhead-valve cylinder head for their first V-twin motorcycle. The vibrato tailpiece unit, however, was what made Bigsby's reputation, as it was used by Gibson, Gretsch and other guitar companies. In 1966, Bigsby sold the company to former Gibson guitar executive Ted McCarty. On May 10, 1999, the Fred Gretsch company purchased the Bigsby company.
- Masurgia.com. "Bigsby Triple Eight High Steel Electric Guitar made for Joaquin Murphy (1947)". Retrieved 2006-11-04.
- BigsbyGuitars.com. "Bigsby Guitars & Vibratos – Official Website – Company History". Retrieved 2014-03-07.


text:
Green Art Gallery presents Proposals on Monumentality, group show curated by İpek Ulusoy Akgül, and featuring the work of Aslı Çavuşoğlu, Iman Issa, Christian Jankowski, Amina Menia, Seher Shah and Santiago Sierra.
The exhibition poses a set of questions for us to reflect upon: Can monuments go beyond representing the past and evoking collective memory? Is it possible for them to resist absorption into memorial narratives? How can monuments express fragmentation and forgetting?
Working across different histories and geographies, Proposals on Monumentality offers possible scenarios and alternative perceptions for monuments. Both Christian Jankowski and Aslı Çavuşoğlu make specific references to historical monuments: the former humorously suggests a need to fight or challenge history, while the latter rephrases the fragile story of a long-gone memorial. Similarly, Amina Menia gazes at the often-forgotten (and sometimes ignored or harmed) monuments as she draws on Nietzsche: 'the past must be forgotten if it is not to become the gravedigger of the present.' While Seher Shah demonstrates a formal exploration into monumentality through strong visual gestures, Iman Issa and Santiago Sierra present alternative structures through abstracting an existing monument and imagining a new one respectively.
As architecture receives increasing significance in the Gulf, iconic landmark buildings and large-scale museum projects – both agents of urban branding – are popularly described as 'monuments'. Moreover, the development and redevelopment of cities, in other words constant flux of urban fabric, lead to feelings of dislocation and even spatial amnesia. In light of the region's changing political context and urban environment, it is much needed to revisit monumentality's complex relation to memory as well as spatial and political dynamics.


Friction: When the rubber meets the road!!!
This Intergating Technology ebook was created by Joshua Coleman for the 8th grade science classes of Burney Harris Lyons Middle School.
stand back
burn out
GPS standard S8P1: Students will investigate the relationship between force, mass, and the motion of objects.
PLO: Students will be able to scientifically explain the phenomenon of friction between rubber tires and and road surfaces.


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Mini private key format
The mini private key format is a method of encoding a Bitcoin private key in as few as 22 characters so that it can be embedded in a small space. This private key format was first used in Casascius physical bitcoins, and is also favorable for use in QR codes. The fewer characters encoded in a QR code, the lower dot density can be used, as well as more dots allocated to error correction in the same space, significantly improving readability and resistance to damage. The mini private key format offers its own built-in check code as a small margin of protection against typos.
An example key using this encoding is S4b3N3oGqDqR5jNuxEvDwf.
Usage on a physical bitcoin
The way it might appear within a physical bitcoin is on a round card printed as follows:
To import the minikey in a user-friendly way the browser-wallet StrongCoin can be used.
The private key encoding consists of 22, 26, or 30 alphanumeric characters from the base58 alphabet used in Bitcoin. The first of the characters is always the uppercase letter S.
There are two methods to obtain the full 256-bit private key. One involves SHA256, and the other involves PBKDF2. A simple test must be performed to determine which method shall be used:
- Add a question mark to the end of the mini private key string.
- Take the SHA256 hash of the entire string. However, we will only looking at the first two bytes of the result.
- If the first byte is 00, then the private key must be computed as simply SHA256(minikey). The question mark is not part of this computation.
- If the first byte is 01, then the private key must be computed using PBKDF2. The second byte determines the iteration count that will be passed into the PBKDF2 function. The iteration count is determined as follows: 2 ^ (n/4) rounded to the nearest integer, where n is the second byte. For example, if the second byte is 0x28, then 4096 iterations will be used. The salt string is "Satoshi Nakamoto". The Bitcoin client imposes an upper limit on the value of n, which is currently 0x40, or 65536 iterations, and rejects the key as invalid beyond the limit.
Example with SHA256
Here is an example with the sample private key S4b3N3oGqDqR5jNuxEvDwf.
The string "S4b3N3oGqDqR5jNuxEvDwf?" has a SHA256 value that begins with 00, so it uses SHA256.
To obtain the full 256-bit private key, simply take the SHA256 hash of the entire string. There is no encoding for breaks in the string even if printed that way - the SHA256 should be taken of exactly twenty-two bytes.
SHA256("S4b3N3oGqDqR5jNuxEvDwf") = 0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D
Example with PBKDF2
Here is an example with the sample private key SmbM4uRBu2mQymCsuMKkiW.
The string "SmbM4uRBu2mQymCsuMKkiW?" has a SHA256 value that begins with 01 30 (hex), so it will use PBKDF2 with 4096 iterations.
To obtain the full 256-bit private key, evaluate the PBKDF2 function as follows:
PBKDF2("SmbM4uRBu2mQymCsuMKkiW", "Satoshi Nakamoto", 4096, 32bytes) = 80366610e37e56c5125aee358ab51326a15f6586d658b90bb881a6116b06853c
The PBKDF2 key derivation algorithm is shared by the WPA-PSK encryption method used on WiFi networks. It also happens to also use 4096 iterations and 32 bytes of key, so a standard WPA key calculator can be used to test and confirm this particular result, simply by entering "Satoshi Nakamoto" as the SSID and "SmbM4uRBu2mQymCsuMKkiW" as the password.
The mini private key format offers a simple typo check code. Mini private keys must be generated in a "brute force" fashion, keeping only keys that conform to the format's rules. If a key is well-formed (22, 26, or 30 Base58 characters starting with S), but fails the hash check, then it probably contains a typo.
If the SHA256 hash of the string followed by '?' doesn't result in something that begins with 0x00 or 0x01, the mini private key is not valid.
If it starts with 0x01, but the second byte is higher than the allowed maximum (0x30), the mini private key is invalid. Note that the maximum is likely to be increased as computing power advances.
Creating mini private keys
Creating mini private keys is relatively simple. One program which can create such keys is Casascius Bitcoin Utility.
Mini private keys must be created "from scratch", as the conversion from mini private key to full-size private key is one-way. In other words, there is no way to convert an existing full-size private key into a mini private key.
To create mini private keys, simply create random strings that satisfy the well-formedness requirement, and then eliminate the ones that do not pass the typo check. (This means eliminating more than 99% of the candidates.) Then use the appropriate algorithm to compute the corresponding private key, and in turn, the matching Bitcoin address. The Bitcoin address can always be computed from just the private key.
It is highly recommended to use the PBKDF2 function and select at least 4096 rounds. (This means selecting strings as keys whose SHA256(string+"?") begins with 0x0128). Mini private keys offer a minimum of entropy, so the more rounds you choose, the stronger your keys will resist advances in technology to do brute-force cracks.
The SHA256 function is provided for the convenience of hardware and software environments that offer very limited computational power, such as microcontrollers. It provides for the ability to generate a valid mini private key with, on average, 256 operations of SHA256. However, it also offers the lowest brute force attack resistance. Such keys are only suitable for situations where a "throwaway" Bitcoin address is needed, such as on a coupon or ticket where the amount will be spent soon, as opposed to an address where bitcoins will be kept long term. The strongest possible PBKDF2-based keys should always be preferred in any environment where generating them is possible.
In all cases, you must use a secure cryptographic random number generator to eliminate risks of predictability of the random strings.
The 22-character mini private key code appears to offer about 123 bits of entropy, determined as log2(58^21). (Because the first character is fixed, there are 21 symbols which can each have one of 58 values).
The 26-character version offers about 146 bits of entropy by the same calculation. The 30-character version offers over 169 bits, which exceeds the 160-bits found in a Bitcoin address.
The following code produces sample SHA256-based mini private keys in Python. For real-world use, random must be replaced with a better source of entropy, as the Python documentation for random states the function "is completely unsuitable for cryptographic purposes".
import random import hashlib BASE58 = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz' def Candidate(): """ Generate a random, well-formed mini private key. """ return('%s%s' % ('S', ''.join( [BASE58[ random.randrange(0,len(BASE58)) ] for i in range(21)]))) def GenerateKeys(numKeys = 10, additionalSecurity = False): """ Generate mini private keys and output the mini key as well as the full private key. numKeys is The number of keys to generate, and """ keysGenerated = 0 totalCandidates = 0 while keysGenerated < numKeys: try: cand = Candidate() # Do typo check t = '%s?' % cand # Take one round of SHA256 candHash = hashlib.sha256(t).digest() # Check if the first eight bits of the hash are 0 if candHash == '\x00': privateKey = GetPrivateKey(cand) print('\n%s\nSHA256( ): %s\nsha256(?): %s' % (cand, privateKey, candHash.encode('hex_codec'))) if CheckShortKey(cand): print('Validated.') else: print('Invalid!') keysGenerated += 1 totalCandidates += 1 except KeyboardInterrupt: break print('\n%s: %i\n%s: %i\n%s: %r\n%s: %.1f' % ('Keys Generated', keysGenerated, 'Total Candidates', totalCandidates, 'Additional Security', additionalSecurity, 'Reject Percentage', 100*(1.0-keysGenerated/float(totalCandidates)))) def GetPrivateKey(shortKey): """ Returns the hexadecimal representation of the private key corresponding to the given short key. """ if CheckShortKey(shortKey): return hashlib.sha256(shortKey).hexdigest() else: print('Typo detected in private key!') return None def CheckShort


OpenWGA 7.6 - WebTML reference
WebTML tags
<tml:navigator>
Description :
Renders an navigator. Depending on the type attribute this tag iterates for e.g. over all children of the current content document.
Derived from: Attributes:
show inherited attributes ...
Name Value(s) Purpose
allareas true | false | t | f | 0 | 1 Only valid for type="sitemap". Specifies if only the documents of the current area or of all areas should be selected.
alllanguages true | false | t | f | 0 | 1 Only valid for type="languages". Specifies if the current content document should be included in the navigation ("true") or only the other language versions of the current structentry should be displayed "false".
allowdefaultlang true | false | t | f | 1 | 0 Specifies if the navigator is allowed to fall back to the default language of the database if no content document exists in the preferred language of the user or in the current language.
contentclass contentclass Determines a content class of the documents to retrieve for navigator types "sourcesOfIncomingRelations" and "sourcesOfIncomingRelationGroup"
exclude context-expression Defines a document which should be excluded from the navigator.
maxlevel 1...n Only valid for type="sitemap". Specifies the maximum document level for the navigation output. Documents which are below this level in the hierarchy will not be selected.
order order-expression Determines the order in which this navigator will put out documents
relation relation-name Determines a relation to use for navigator type "sourcesOfIncomingRelations"
relationgroup relationgroup-name Determines a relation group to use for navigator types "relationGroupTargets" or "sourcesOfIncomingRelationGroups"
role none | nav | search | sitemap Allows to switch the role of the navigator.
type children | siblings | parents |path | sitemap | languages | areas Specifies the type of this navigator and the documents for the iteration. (children, siblings, etc.)
Details:
Valid shortcuts for this tag:
<tml:children ...> equals to <tml:navigator type="children" ...>
<tml:siblings ...> equals to <tml:navigator type="siblings" ...>
<tml:parents ...> equals to <tml:navigator type="parents" ...>
<tml:path ...> equals to <tml:navigator type="path" ...>
<tml:sitemap ...> equals to <tml:navigator type="sitemap" ...>
<tml:languages...> equals to <tml:navigator type="languages" ...>


text:
In developing our sensors, we therefore concentrate on the needs of selected focus industries – such as the filling and packaging of beverages. This is one reason why we have developed special solutions for the detection of transparent bottles or labels, e.g., with our PRK 18B and GSU 14C. The MLD 300 and 500 multiple light beam safety devices also demonstrate how efficient professional safety at work can be today in the beverage industry.
- Unique successor model of our PRK 18 in chemically nickel-plated metal housing;
- The calibrated aBEAM optics precisely strike even small reflectors without time-consuming alignment;
- Precise repeatability thanks to a jitter time of just 32 μs;
- Tracking function considerably reduces the amount of work required for cleaning and readjustment.
- Precise detection of labels in robust metal housing;
- Ultrasonic forked sensor for reliable detection and universal application;
- ALC – Automatic Level Control pervents stops resulting from soiling or changes in the material;
- Special functions for transparent labels on transparent carrier.
MLD 300 и 500
- Integrated muting functions can be configured wiring connections;
- Laser alignment aid for easy alignment over long distances;
- All settings and configuration of the muting modes without PC;
- Direct connection to AS-i bus without additional coupling module.


text:
About this book
"Data-Driven 3D Facial Animation" systematically describes the emerging data-driven techniques developed over the last ten years or so. Although data-driven 3D facial animation is used more and more in animation practice, to date there have been very few books that specifically address the techniques involved.
Comprehensive in scope, the book covers not only traditional lip-sync (speech animation), but also expressive facial motion, facial gestures, facial modeling, editing and sketching, and facial animation transferring. It provides an up-to-date reference source for academic research and for professionals working in the facial animation field. An edited volume, the book brings together contributions from leading researchers and practitioners working in both academia and in the leading animation studios.


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Mathematica Stack Exchange is a question and answer site for users of Mathematica. It's 100% free, no registration required.
Assume $X$ is an exponential random variable with unit mean ($f_X(x)=e^{-x}$, $x>0$). I want to calculate the expected value of $\frac{1}{X}$. Since $X>0$, I am expecting that $\mathbb{E}(\frac{1}{X})>0$, but Mathematica gives some negative value. I tried the following input:
Expectation[1/x, {x \[Distributed] ExponentialDistribution[1]}]
and Mathematica 's answer is: -EulerGamma
Is it possible? Am I doing some mistakes?
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What does Mathematica give you when you use the definition: $\int_0^\infty e^{-x}/x\,dx$ ... ? – GEdgar Aug 10 '12 at 14:00

On Mathematica 9.0.0, Mathematica simply returns the input when entering your line of code. – Jacob Akkerboom Jul 17 '13 at 9:41
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2 Answers
Instead of the exponential distribution, consider its truncation $\mathcal{E}_\epsilon(1)$ to $(\epsilon, \infty)$. The expectation can then be found, but it diverges as $\epsilon \downarrow 0$.
enter image description here
Indeed, writing the expectation as integral: $$ \int_0^\infty \frac{1}{x} \mathrm{e}^{-x} \mathrm{d} x $$ you see that the integral diverges at the lower bound. Thus, while it is natural to expect $\mathbb{E}\left(X^{-1}\right) > 0$, the expectation is infinite.
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1
Shouldn't Mathematica's output be Infinity instead of -EulerGamma? The latter is evidently wrong. – Sjoerd C. de Vries Aug 10 '12 at 20:23
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@SjoerdC.deVries It could be Infinity, or it could bounce unevaluated. Current output results from use of GenerateConditions->False, as a way to turn off convergence checking. It has an undesirable side effect, that Integrate returns "renormalized answers", i.e. regularized and the divergent part subtracted. Try Integrate[Exp[-x]/x,{x,0,Infinity},GenerateConditions->False]. – Sasha Aug 10 '12 at 20:28
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Here's a way to see why it diverges to infinity: Observe that $e^{-x}>1/3$ (since $0<e<3$) if $0<x<1$, so $$ \int_0^\infty \frac 1 x e^{-x} \, dx \ge \int_0^1 \frac 1 x e^{-x} \, dx \ge \int_0^1 \frac 1 x \cdot \frac 1 3 \, dx = \infty. $$
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