an atlhlete runs around a track that is 100mts long for 3 times and then stops. what is the athletes distance and sisplacement?
Asked by arajeevshashank | 14th Feb, 2018, 06:49: PM
Expert Answer:
distance covered is 100 x 3 =300 mts
displacement = distance between final position and initial position
since runner comes back to same position which he started
so displacement is zero
Answered by Arun | 15th Feb, 2018, 09:29: AM


text:
Neiker-Tecnalia estimates the growth of vines using an innovative system that measures their infrared radiation emission
The Basque Institute of Agricultural Research and Development Neiker Tecnalia has tested the effectiveness of an innovative system to estimate vegetative growth in vines by measuring the infrared radiation emission of the plants. The method is known as the Normalized Difference Vegetation Index (NDVT) and estimates the vegetative growth of plants by measuring the solar radiation that plants reflect in the red and near-infrared band of the electromagnetic spectrum.
In order to provide farmers and anyone else involved in managing agricultural ecosystems with a tool enabling them to assess the impact of their farming practices on the health of their crops and soils, the Basque Institute for Agricultural Research and Development NEIKER-Tecnalia has created its new TSEAs or 'Agricultural Ecosystem Health Cards'. These handbooks are an improved version of the cards created in the 1980s by the United States Department of Agriculture. The R&D centre is holding various meetings to make these handbooks known to various groups (growers, technicians, scientists and the administration) linked to the agricultural sector and who will receive them free of charge.

source: openbmb/Ultra-FineWeb


text:
Effects of the Mt. Pinatubo eruption on the stratospheric aerosols and the solar insolation over the Western Pacific were estimated by sunphotometer and pyranometer on board ships. The sunphotometer measurements showed that the columnar aerosol optical thickness increased by 0.3 at 500 nm over the latitude from 30°N to 30°S, while that without the influence of volcanic eruptions is less than 0.1. The aerosol optical thickness became minimum in the summer of 1992, and increased again after the summer. The shipboard pyranometer measurements showed that solar insolation decreased after the eruption by 1.4∼4.1% compared with that before the eruption. This value is larger than that calculated with radiative transfer code, based on the aerosol model estimated from the sunphotometry.
|Number of pages||4|
|Journal||Geophysical Research Letters|
|Publication status||Published - 1994 Jun 15|
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)

source: m-a-p/FineFineWeb


text:
Tungsten oxide is not only a type of infrared thermal insulation nano material, but a photocatalytic material. Orthorhombic hydrate tungsten trioxide (o-WO3•0.33H2O) flower-like hierarchical structure may be synthesized via solvothermal method by regulating the amount of acetone. And the photocatalytic testing was carried out and the results showed that flower-like hierarchical structure tungsten trioxide hydrate displays superior photocatalytic performance than thorn sphere tungsten trioxide hydrate. And 88.5% of RhB may be eliminated after 240min.
The results also showed that: Compared with the morphology of orthorhombic hydrate tungsten trioxide thorn sphere (synthesized without adding acetone), (020) facet of orthorhombic tungsten trioxide hydrate can be reserved by acetone adsorption, and the flower-like hierarchical structure has been obtained.
In addition, the morphology of flower-like hierarchical structure has been influenced by the amount of acetone, due to the change of saturation vapor pressure in reaction system. And the visible-light absorption of sample has been improved by the increment of acetone.
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text:
Previous research has shown that flumioxazin, a herbicide being developed as a postemergence-directed spray (PDS) in cotton, has the potential to injure cotton less than 30 cm tall if the herbicide contacts green stem tissue by rain splash or misapplication. In response to this concern, five-leaf cotton plants with chlorophyllous stems and older cotton, 16-leaf cotton plants, with bark on the lower stem were treated with a PDS containing flumioxazin plus crop oil concentrate (COC) or nonionic surfactant (NIS). Stems of treated plants and untreated plants at the respective growth stage were cross-sectioned and then magnified and photographed using bright-field microscopy techniques. More visible injury consisting of necrosis and desiccation was evident in younger cotton. Also, there was a decrease in treated-stem diameter and an increase in visible injury with COC compared with NIS in younger cotton. The effects of plant growth stage and harvest time on absorption, translocation, and metabolism of 14C-flumioxazin in cotton were also investigated. Total 14C absorbed at 72 h after treatment (HAT) was 77, 76, and 94% of applied at 4-, 8-, and 12-leaf growth stages, respectively. Cotton at the 12-leaf stage absorbed more 14C within 48 HAT than was absorbed by fouror eight-leaf cotton by 72 HAT. A majority (31 to 57%) of applied 14C remained in the treated stem for all growth stages and harvest times. Treated cotton stems at all growth stages and harvest times contained higher concentrations (Bq g−1) of 14C than any other tissues. Flumioxazin metabolites made up less than 5% of the radioactivity found in the treated stem. Because of the undetectable levels of metabolites in other tissues when flumioxazin was applied PDS, flumioxazin was foliar applied to determine whether flumioxazin transported to the leaves may have been metabolized. In foliar-treated cotton, flumioxazin metabolites in the treated leaf of four-leaf cotton totaled 4% of the recovered 14C 72 HAT. Flumioxazin metabolites in the treated leaf of 12-leaf cotton totaled 35% of the recovered 14C 48 HAT. These data suggest that differential absorption, translocation, and metabolism at various growth stages, as well as the development of a bark layer, are the bases for differential tolerances of cotton to flumioxazin applied PDS.
Nomenclature: Flumioxazin; cotton, Gossypium hirsutum L.


text:
Full Moon of First Lunar Month: Customs, Dishes and Meaning
The full moon day of the first lunar month is also known as Tet Nguyen Tieu. This year, the festival falls on Feb. 15. On the day, Vietnamese worship their ancestors, go to pagodas, and pray to the Buddha for good fortune for themselves and their families.
|Photo: Bach hoa Xanh|
Meaning of the first full moon
Tet Nguyen Tieu is an important festival in the spiritual life of Vietnamese people. There is a saying: "A year-round offering is not as good as a single one on the first full moon," which identifies the festival's significance.
Many people believe that Buddha arrives on the earth on Nguyen Tieu, so on the first full moon, people often go to the pagodas to pray for peace and luck. In the old times, farmers often start farming on the first full moon. Before going to the field, they prepare offering trays to the gods and ancestors, wishing for favorable weather and a bountiful harvest.
Some documents point out that the customs of worship for the first full month was born in China then was gradually spread to other Asian countries. In the process of cultural interference, Vietnam and other countries in the region have found their own ways to celebrate the occasion.
Recipes of traditional dishes
|Savory steamed chicken (Photo: CET)|
Savory steamed chicken
Ingredients: a chicken of 1.3- 1.5kg, two cups of salt, eight lemongrass, ten lime leaves, two purple onions, five green chili peppers
- Pound or grind 2 sliced lemongrasses, onion, chili, a tablespoon of salt to, rub the mixture on the chicken to marinate for 30 minutes. Stuff the chicken belly with lemongrass and lime leaves.
- Add two cups of salt, lemongrass, lime leaves to a pot, then put the chicken on.
- Steam for 45 minutes on high heat or until the chicken is well cooked.
|Pork skin soup (Photo: Thuc Than)|
Pork skin soup
Ingredients: 200g of pork bone, 200g of pork paste, 100g - 200g of black tiger shrimp, 200g of shiitake mushrooms, 100g of cauliflower, 100g of carrots, 50g of dry pork skin, salt, pepper, cilantro.
- Soak the dry pork skin in warm water, then cut into small pieces.
- Peel the shrimp.
- Cut vegetables into small pieces.
- Stew the bones at low heat for 30 minutes to get the broth. Add the carrots, cauliflower, mushrooms, and pork skin.
- Make meatballs from pork paste, then add the balls and shrimp into the pot.
- Leave the pot for boiling for 5 minutes, then turn off the heat, pour the soup into bowls and garnish with coriander.
|Jelly meat (Photo: VNE)|
Ingredients: 400g of pork leg, 150g of fresh pork skin, a small onion, three purple onions, 50g of black wood ear, 1 teaspoon of fish sauce, a pinch of MSG, 1 teaspoon of crushed pepper.
- Wash the pork and cut it into big pieces, then boil them with a pinch of salt. While boiling, take out the foam to keep the broth clear.
- When the meat is cooked, lower the heat, add pepper and onion to stew for about 25 minutes, then take the pork out while keep boiling the broth. Add wood ear mushrooms and cook for another 10 minutes, seasoning to taste.
- Pour the mixture into a bowl, put it in the refrigerator for several hours for cooling down.
On the God of Wealth's Day (Jan. 10 in the lunar calendar), grilled snakehead fish are sold on every street. Here is the meaning behind ...
Herman prepares banana leaves, pork, green beans, sticky rice, and a handcrafted square cardboard mold for the famed Vietnamese Traditional Banh Chung, which also happens ...
Audiences cheer for Vietnamese traditional music in France presented by veteran artist Ho Thuy Trang


Select case statements
Instead of using an ELSE...IF structure, you can use a select case statement to execute one statement among many alternatives. The basic idea behind using a select statement is to give an expression to evaluate and several different statements to execute based on the value of the expression. Each case in a select statement is checked against value of the expression until a match is found. Once a match is found, the execution of the select case statement ends. If no match is found, a default case, if specified, is executed. The basic syntax for a select case statement is:
Select case expression
Case value1
code to execute when a value1 equals expression
Case value2
code to execute when a value2 equals expression
Case value3
code to execute when a value3 equals expression
Case valueN
code to execute when a valueN equals expression
Case else
code to execute when a no match is found among the choices listed above
Let's start with an example that shows how to use the select case statement:
dim result, sout
for i = 1 to 10
result = i mod 2
select case result
case 0
sout = sout & i & " is even"
case 1
sout = sout & i & " is odd"
end select
response.write sout
In this example we use a for loop to iterate the variable i from 1 through 10. With each value for i, we determine if the value is divisible by 2. On line 4, we start our select case statement and our expression is the value of result. The value of result is going to be either 0 or 1. As the loop and select case statement executes, the value of result will be checked with 0, and 1; see lines 5 and 7, respectively. The following shows the output of the above code:
1 is odd
2 is even
3 is odd
4 is even
5 is odd
6 is even
7 is odd
8 is even
9 is odd
10 is even


text:
Cristi is a pediatric nurse practitioner who absolutely loves working with children and their families. She has always known she wanted to work with children and has spent the last five years working on the Pediatric Bone Marrow Transplant unit at Duke University Hospital. She loves to work collaboratively with her patients and their families to develop long-lasting, trusting relationships.
Twinkly lights, candles, holiday trees, plants, ornaments, and other decorations are an important part of holiday celebrations. Besides being festive and fun, the decorations your family brings out every year can help children feel connected to family traditions. See tips from AAP on how to make sure your decorations are safe.
The first semester of school is nearing an end, kids are well into sports seasons, the weather is changing and the Holidays are upon us. While it may seem that the worst of the flu season is behind us, flu season is still in full swing. And it is not too late for you and...
Ashleigh Martin is a Certified Pediatric Nurse Practitioner who is passionate about the care of children from the newborn stage into young-adulthood. She has worked with children and families in some capacity since she was in high school. She believes strongly in providing evidence-based guidance and recommendations to help families make the best health decisions for their children.
Both the flu (influenza) and COVID-19 will be spreading this fall and winter, especially among people who are not vaccinated. The two contagious respiratory viruses cause similar symptoms, so it can be hard to tell them apart.
Choosing costumes, decorating pumpkins, and getting special treats brings joy to many children at Halloween. Some Halloween traditions may still look different this year to keep everyone safe during the COVID-19 pandemic. With increased vaccinations in kids and adults, trick or treating may be an option again. If you are concerned for the safety of your family however, there are still plenty of ways you can have fun while avoiding the fear of being exposed to or spreading the virus through trick or treating.
School is back in full swing, and among balancing homework, school sports and COVID-19 protocols, now is the time to start thinking about also protecting your children against the flu. The flu season usually starts in the fall and ends in the spring. When there is an outbreak of the flu, usually during the winter...


text:
Interdisciplinary Middle Years Multimedia Model
The Interdisciplinary Middle Years Multimedia (IMYM) model grew out of the successful curriculum-based research and development project of the same name, which was piloted in the years _PHONE_.
The IMYM model demonstrated how the infusion of information and communication technologies (ICT) with promising instructional practices such as inquiry and constructivism could add value to teaching, learning, and assessing.
IMYM was assessed internally using action research strategies and externally by a Canadian educational research company. The IMYM model was piloted in nearly 100 rural and urban schools throughout Manitoba and is still being implemented voluntarily in schools and school divisions across the province.
Since 2005, the Literacy with ICT Across the Curriculum initiative carries on with the model first developed by IMYM.

source: HuggingFaceFW/fineweb-edu


17.6. PCA Watchdog Timer
Reset" on page 133 for more information on the use and configuration of the WDT.
10.2. Stop Mode
Setting the stop mode Select bit (PCON.1) causes the controller core to enter stop mode as soon as the
instruction that sets the bit completes execution. In stop mode the internal oscillator, CPU, and all digital
peripherals are stopped; the state of the external oscillator circuit is not affected. Each analog peripheral
(including the external oscillator circuit) may be shut down individually prior to entering stop mode. Stop
mode can only be terminated by an internal or external reset. On reset, the device performs the normal
reset sequence and begins program execution at address 0x0000.
If enabled, the Missing Clock Detector will cause an internal reset and thereby terminate the stop mode.
The Missing Clock Detector should be disabled if the CPU is to be put to in STOP mode for longer than the
MCD timeout.
By default, when in stop mode the internal regulator is still active. However, the regulator can be configured to shut down while in stop mode to save power. To shut down the regulator in stop mode, the
STOPCF bit in register REG01CN should be set to 1 prior to setting the STOP bit (see SFR Definition 9.1).
If the regulator is shut down using the STOPCF bit, only the RST pin or a full power cycle are capable of
resetting the device.
10.3. Suspend Mode
Setting the SUSPEND bit (OSCICN.5) causes the hardware to halt the high-frequency internal oscillator
and go into suspend mode as soon as the instruction that sets the bit completes execution. All internal registers and memory maintain their original data. The CPU is not halted in Suspend, so code can still be executed using an oscillator other than the internal high-frequency oscillator.
Suspend mode can be terminated by resume signalling on the USB data pins, or a device reset event.
When suspend mode is terminated, if the oscillator source is the internal high-frequency oscillator, the
device will continue execution on the instruction following the one that set the SUSPEND bit. If the wake
event was configured to generate an interrupt, the interrupt will be serviced upon waking the device. If suspend mode is terminated by an internal or external reset, the CIP-51 performs a normal reset sequence
and begins program execution at address 0x0000.
77
Rev. 1.4
C8051F380/1/2/3/4/5/6/7/C
SFR Definition 10.1. PCON: Power Control
Bit
7
6
5
4
3
2
1
0
Name
GF[5:0]
STOP
IDLE
Type
R/W
R/W
R/W
0
0
Reset
0
0
0
SFR Address = 0x87; SFR Page = All Pages
Bit
Name
0
0
0
Function
7:2
GF[5:0]
General Purpose Flags 5–0.
These are general purpose flags for use under software control.
1
STOP
Stop Mode Select.
Setting this bit will place the CIP-51 in stop mode. This bit will always be read as 0.
1: CPU goes into stop mode (internal oscillator stopped).
0
IDLE
IDLE: Idle Mode Select.
Setting this bit will place the CIP-51 in Idle mode. This bit will always be read as 0.
1: CPU goes into Idle mode. (Shuts off clock to CPU, but clock to Timers, Interrupts,
Serial Ports, and Analog Peripherals are still active.)
Rev. 1.4
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11. CIP-51 Microcontroller
The MCU system controller core is the CIP-51 microcontroller. The CIP-51 is fully compatible with the
MCS-51™ instruction set; standard 803x/805x assemblers and compilers can be used to develop software. The MCU family has a superset of all the peripherals included with a standard 8051. The CIP-51
also includes on-chip debug hardware (see description in Section 28), and interfaces directly with the analog and digital subsystems providing a complete data acquisition or control-system solution in a single integrated circuit.
The CIP-51 Microcontroller core implements the standard 8051 organization and peripherals as well as
additional custom peripherals and functions to extend its capability (see Figure 11.1 for a block diagram).
The CIP-51 includes the following features:




Fully Compatible with MCS-51 Instruction Set
48 MIPS Peak Throughput with 48 MHz Clock
0 to 48 MHz Clock Frequency
Extended Interrupt Handler




Reset Input
Power Management Modes
On-chip Debug Logic
Program and Data Memory Security
Performance
The CIP-51 employs a pipelined architecture that greatly increases its instruction throughput over the standard 8051 architecture. In a standard 8051, all instructions except for MUL and DIV take 12 or 24 system
clock cycles to execute, and usually have a maximum system clock of 12 MHz. By contrast, the CIP-51
core executes 70% of its instructions in one or two system clock cycles, with no instructions taking more
than eight system clock cycles.
Figure 11.1. CIP-51 Block Diagram
Rev. 1.4
79
C8051F380/1/2/3/4/5/6/7/C
With the CIP-51's maximum system clock at 48 MHz, it has a peak throughput of 48 MIPS. The CIP-51 has
a total of 109 instructions. The table below shows the total number of instructions that require each execution time.
Clocks to Execute
1
2
2/4
3
3/5
4
5
4/6
6
8
Number of Instructions
26
50
5
10
6
5
2
2
2
1
Programming and Debugging Support
In-system programming of the Flash program memory and communication with on-chip debug support
logic is accomplished via the Silicon Labs 2-Wire Development Interface (C2).
The on-chip debug support logic facilitates full speed in-circuit debugging, allowing the setting of hardware
breakpoints, starting, stopping and single stepping through program execution (including interrupt service
routines), examination of the program's call stack, and reading/writing the contents of registers and memory. This method of on-chip debugging is completely non-intrusive, requiring no RAM, Stack, timers, or
other on-chip resources. C2 details can be found in Section "28. C2 Interface" on page 316.
The CIP-51 is supported by development tools from Silicon Labs and third party vendors. Silicon Labs provides an integrated development environment (IDE) including editor, debugger and programmer. The IDE's
debugger and programmer interface to the CIP-51 via the C2 interface to provide fast and efficient in-system device programming and debugging. Third party macro assemblers and C compilers are also available.
11.1. Instruction Set
The instruction set of the CIP-51 System Controller is fully compatible with the standard MCS-51™ instruction set. Standard 8051 development tools can be used to develop software for the CIP-51. All CIP-51
instructions are the binary and functional equivalent of their MCS-51™ counterparts, including opcodes,
addressing modes and effect on PSW flags. However, instruction timing is different than that of the standard 8051.
11.1.1. Instruction and CPU Timing
In many 8051 implementations, a distinction is made between machine cycles and clock cycles, with
machine cycles varying from 2 to 12 clock cycles in length. However, the CIP-51 implementation is based
solely on clock cycle timing. All instruction timings are specified in terms of clock cycles.
Due to the pipelined architecture of the CIP-51, most instructions execute in the same number of clock
cycles as there are program bytes in the instruction. Conditional branch instructions take one less clock
cycle to complete when the branch is not taken as opposed to when the branch is taken. Table 11.1 is the
CIP-51 Instruction Set Summary, which includes the mnemonic, number of bytes, and number of clock
cycles for each instruction.
80
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Table 11.1. CIP-51 Instruction Set Summary
Mnemonic
Arithmetic Operations
ADD A, Rn
ADD A, direct
ADD A, @Ri
ADD A, #data
ADDC A, Rn
ADDC A, direct
ADDC A, @Ri
ADDC A, #data
SUBB A, Rn
SUBB A, direct
SUBB A, @Ri
SUBB A, #data
INC A
INC Rn
INC direct
INC @Ri
DEC A
DEC Rn
DEC direct
DEC @Ri
INC DPTR
MUL AB
DIV AB
DA A
Logical Operations
ANL A, Rn
ANL A, direct
ANL A, @Ri
ANL A, #data
ANL direct, A
ANL direct, #data
ORL A, Rn
ORL A, direct
ORL A, @Ri
ORL A, #data
ORL direct, A
ORL direct, #data
XRL A, Rn
XRL A, direct
XRL A, @Ri
XRL A, #data
XRL direct, A
Description
Bytes
Clock
Cycles
Add register to A
Add direct byte to A
Add indirect RAM to A
Add immediate to A
Add register to A with carry
Add direct byte to A with carry
Add indirect RAM to A with carry


Workspace Class
Definition
A workspace provides access to a active set of source code projects and documents and their associated syntax trees, compilations and semantic models. A workspace has a current solution that is an immutable snapshot of the projects and documents. This property may change over time as the workspace is updated either from live interactions in the environment or via call to the workspace's TryApplyChanges(Solution) method.
public ref class Workspace abstract : IDisposable
public abstract class Workspace : IDisposable
type Workspace = class
 interface IDisposable
Public MustInherit Class Workspace
Implements IDisposable
Inheritance
Workspace
Derived
Implements
Constructors
Workspace(HostServices, String)
Constructs a new workspace instance.
Properties
CanOpenDocuments
True if this workspace supports manually opening and closing documents.
CurrentSolution
The current solution.
The solution is an immutable model of the current set of projects and source documents. It provides access to source text, syntax trees and semantics.
This property may change as the workspace reacts to changes in the environment or after TryApplyChanges(Solution) is called.
Kind
The kind of the workspace. This is generally Host if originating from the host environment, but may be any other name used for a specific kind of workspace.
Options
Gets or sets the set of all global options.
PartialSemanticsEnabled
Override this property if the workspace supports partial semantics for documents.
Services
Services provider by the host for implementing workspace features.
Methods
AdjustReloadedProject(Project, Project)
AdjustReloadedSolution(Solution, Solution)
This method is called during OnSolutionReload. Override this method if you want to manipulate the reloaded solution.
ApplyAdditionalDocumentAdded(DocumentInfo, SourceText)
This method is called during TryApplyChanges(Solution) to add a new additional document to a project.
Override this method to implement the capability of adding additional documents.
ApplyAdditionalDocumentRemoved(DocumentId)
This method is called during TryApplyChanges(Solution) to remove an additional document from a project.
Override this method to implement the capability of removing additional documents.
ApplyAdditionalDocumentTextChanged(DocumentId, SourceText)
This method is called to change the text of an additional document.
Override this method to implement the capability of changing additional document text.
ApplyAnalyzerConfigDocumentAdded(DocumentInfo, SourceText)
This method is called during TryApplyChanges(Solution) to add a new analyzer config document to a project.
Override this method to implement the capability of adding analyzer config documents.
ApplyAnalyzerConfigDocumentRemoved(DocumentId)
This method is called during TryApplyChanges(Solution) to remove an analyzer config document from a project.
Override this method to implement the capability of removing analyzer config documents.
ApplyAnalyzerConfigDocumentTextChanged(DocumentId, SourceText)
This method is called to change the text of an analyzer config document.
Override this method to implement the capability of changing analyzer config document text.
ApplyAnalyzerReferenceAdded(ProjectId, AnalyzerReference)
This method is called during TryApplyChanges(Solution) to add an analyzer reference to a project.
Override this method to implement the capability of adding analyzer references.
ApplyAnalyzerReferenceRemoved(ProjectId, AnalyzerReference)
This method is called during TryApplyChanges(Solution) to remove an analyzer reference from a project.
Override this method to implement the capability of removing analyzer references.
ApplyCompilationOptionsChanged(ProjectId, CompilationOptions)
This method is called during TryApplyChanges(Solution) to change the compilation options.
Override this method to implement the capability of changing compilation options.
ApplyDocumentAdded(DocumentInfo, SourceText)
This method is called during TryApplyChanges(Solution) to add a new document to a project.
Override this method to implement the capability of adding documents.
ApplyDocumentInfoChanged(DocumentId, DocumentInfo)
This method is called to change the info of a document.
Override this method to implement the capability of changing a document's info.
ApplyDocumentRemoved(DocumentId)
This method is called during TryApplyChanges(Solution) to remove a document from a project.
Override this method to implement the capability of removing documents.
ApplyDocumentTextChanged(DocumentId, SourceText)
This method is called to change the text of a document.
Override this method to implement the capability of changing document text.
ApplyMetadataReferenceAdded(ProjectId, MetadataReference)
This method is called during TryApplyChanges(Solution) to add a metadata reference to a project.
Override this method to implement the capability of adding metadata references.
ApplyMetadataReferenceRemoved(ProjectId, MetadataReference)
This method is called during TryApplyChanges(Solution) to remove a metadata reference from a project.
Override this method to implement the capability of removing metadata references.
ApplyParseOptionsChanged(ProjectId, ParseOptions)
This method is called during TryApplyChanges(Solution) to change the parse options.
Override this method to implement the capability of changing parse options.
ApplyProjectAdded(ProjectInfo)
This method is called during TryApplyChanges(Solution) to add a project to the current solution.
Override this method to implement the capability of adding projects.
ApplyProjectChanges(ProjectChanges)
This method is called during TryApplyChanges(Solution) for each project that has been added, removed or changed.
Override this method if you want to modify how project changes are applied.
ApplyProjectReferenceAdded(ProjectId, ProjectReference)
This method is called during TryApplyChanges(Solution) to add a project reference to a project.
Override this method to implement the capability of adding project references.
ApplyProjectReferenceRemoved(ProjectId, ProjectReference)
This method is called during TryApplyChanges(Solution) to remove a project reference from a project.
Override this method to implement the capability of removing project references.
ApplyProjectRemoved(ProjectId)
This method is called during TryApplyChanges(Solution) to remove a project from the current solution.
Override this method to implement the capability of removing projects.
CanApplyChange(ApplyChangesKind)
Determines if the specific kind of change is supported by the TryApplyChanges(Solution) method.
CanApplyCompilationOptionChange(CompilationOptions, CompilationOptions, Project)
CanApplyParseOptionChange(ParseOptions, ParseOptions, Project)
CheckAdditionalDocumentIsInCurrentSolution(DocumentId)
Throws an exception if an additional document is not part of the current solution.
CheckAdditionalDocumentIsNotInCurrentSolution(DocumentId)
Throws an exception if an additional document is already part of the current solution.
CheckAnalyzerConfigDocumentIsInCurrentSolution(DocumentId)
Throws an exception if an analyzer config is not part of the current solution.
CheckAnalyzerConfigDocumentIsNotInCurrentSolution(DocumentId)
Throws an exception if the analyzer config document is already part of the current solution.
CheckCanOpenDocuments()
CheckDocumentCanBeRemoved(DocumentId)
CheckDocumentIsClosed(DocumentId)
CheckDocumentIsInCurrentSolution(DocumentId)
Throws an exception if a document is not part of the current solution.
CheckDocumentIsNotInCurrentSolution(DocumentId)
Throws an exception if a document is already part of the current solution.
CheckDocumentIsOpen(DocumentId)
CheckProjectCanBeRemoved(ProjectId)
Currently projects can always be removed, but this method still exists because it's protected and we don't want to break people who may have derived from Workspace and either called it, or overridden it.
CheckProjectDoesNotContainOpenDocuments(ProjectId)
CheckProjectDoesNotHaveAnalyzerReference(ProjectId, AnalyzerReference)
Throws an exception if a project already has a specific analyzer reference.
CheckProjectDoesNotHaveMetadataReference(ProjectId, MetadataReference)
Throws an exception if a project already has a specific metadata reference.
CheckProjectDoesNotHaveProjectReference(ProjectId, ProjectReference)
Throws an exception if a project already has a specific project reference.
CheckProjectDoesNotHaveTransitiveProjectReference(ProjectId, ProjectId)
Throws an exception if project has a transitive reference to another project.
CheckProjectHasAnalyzerReference(ProjectId, AnalyzerReference)
Throws an exception if a project does not have a specific analyzer reference.
CheckProjectHasMetadataReference(ProjectId, MetadataReference)
Throws an exception if a project does not have a specific metadata reference.
CheckPro


How is Anti vibrant table useful in many types of balances?
 - November 19, 2019
Image result for anti-vibration table
We all know the importance of researches in our life; analyses are responsible for improving life. If a researcher cannot find the real value of the outcome, then he will not be able to do something unique. The same condition is with the medical field; you need to weigh the exact quantity of the substance which you will use to prepare the medicine. Millions of the people consume the drug, so it becomes vital to use the highly precise weighing equipment. An anti vibration table is a piece of excellent equipment which helps in weighing the accurate value.
Which types of balances require anti vibration table?
When we any weight, the environmental factor like noise, construction, and many others affect the determination of value. In scientific work, a scientist needs a piece of equipment that will not vibrate while weight something because to find a precise amount is vital. These are some types for which we can use anti vibration table.
1. Distinctness balance
Many time a researcher use exact balance like .01 g. Such scales can be effect easily from the surrounding factor. For weighing such weight, we need to have an anti vibration table; this table doesn't vibrate and helps to provide the exact results.
2. Analytical balance
If you are weighing a very less weight like .0001 g, then you need to have a piece of high precision equipment that could give you an accurate result. Many researchers use the anti vibration table for determining the right weight. An analytical balance is essential to complete the research efficiently. If there is any problem in balancing the precise value, research will not have an excellent outcome.
3. for semi-micro balance
An anti vibration table can be used for the semi-micro balance. These balances usually contain a balance of 0.0001 g. So it becomes essential to handle highly sensitive equipment for weighing such weight. Many professionals recommend using the anti vibration table for balancing such caliber.
4. for use Microbalance
When you are working in the science lab, there will be many weight like 0.00001 to measure. These types of sensitive balance can be used easily by the anti vibration table.


Staying safe outdoors
Whether you're lifting paving slabs or painting the outside of your house, there are real risks you must address before starting
Dress right
Gloves are essential for most outdoor jobs, especially if you're handling rough materials such as bricks or paving slabs. Use heavy-duty gardening gloves rather than tatty old mittens. You should also wear safety goggles if you're cutting brick, glass or paving or stripping/sanding paint, as any dust you produce can be harmful. Wear proper shoes, too, especially if you're shinning up ladders. Flat, sturdy, non-slip shoes are ladder-proof: open-toed sandals and stilettos are not.
Laws of the ladder
The ladder is a dangerous garden tool. To avoid accidents, follow these simple rules:
1. Check your ladder is in good working order and make sure someone knows what you're up to.
2. Never lean a ladder on guttering, glass or windowsills - always use the wall. Set up the ladder at a safe angle. As a guide, the distance of the feet from the wall should be a quarter of the ladder's height (ie, the feet of a 6m ladder should be positioned 1.5m from the wall).
3. Always rest your ladder on a level surface. If the ground is soft, rest the feet on a hardwood board to stop the feet sinking.
The bottom of the ladder should preferably have non-slip feet.
4. Always maintain three points of contact with the ladder and avoid carrying items up with you - use a tool belt instead. And be aware of the maximum workload of your ladder. This will vary according to the height of your model.
5. While working, keep both feet on the same rung and always face forwards. Don't overreach or you could topple the ladder. Try amd take a break every 30 minutes.
6. Best practice suggests you shouldn't use a ladder any longer than 9m. Never stand on the top three rungs (the top metre) as this will put too much pressure on the top and could cause the legs to collapse. Roof-work requires scaffolding and should be left to the professionals (see panel, p93).
Check the weather forecast
Most outside jobs can't be done in the rain as materials such as cement, mortar and sand need to be kept dry. If you're planning on climbing a ladder, watch out for high winds. Don't risk being 8m up a ladder in gale force winds - wait for the wind to drop first.
The sun may normally be a welcome visitor to your garden but if you're painting the exterior of your house, it can be a menace. The chances are you're painting with bright white paint, which can give you a headache in direct sunlight. Instead, follow the shade around the house to keep out of the sun's glare.
Lift correctly
We all know there's a safe way of lifting but it's only once back problems develop that many of us sit up (if we can) and take notice. If you have to lift something heavy, stand with feet shoulder-width apart to give you a solid base. To pick up your load, squat down bending at the knees and keeping your back straight. This way, you'll be using the power in your legs and saving your back from injury.
And finally... know when to stop
Don't be a DIY hero. If you're not confident about what you're doing, stop and ask a professional for help. Better to bruise your ego than do yourself - or your home - a serious injury.
Handy Andy's top tips
Andy Kane, the tough DIY guru of Changing Rooms fame, shares some of his DIY dos and don'ts.
The easiest DIY advice I can offer is clear your gutters. Your gutters will get blocked up with leaves (especially if you live near trees) and you could easily end up with water running down the side of your house when it overflows. Even if water's not running down the walls, your exterior will get damp if the water bounces back and hits the wall at the bottom. It's simple to sort: get a ladder, get up there and clear the leaves once a year.
Be careful if you're doing up your windows, especially if you have an old house. Make sure you wear a mask when sanding down flaky paint as it may contain lead. The less dust you breathe in the better. If there are chips in the frame you want to fill, make sure you use an exterior filler. If you use an interior filler, it'll look fine until it rains - then all your hard work will go down the pan.
If you're laying a patio, make sure the highest point is nearest your house so water runs away from it. It sounds obvious, but imagine if you got it wrong! If you're making a raised patio, you need to have two courses of brickwork below the DPC (damp-proof course) before you lay your patio slabs. If you don't, the water will rise and you'll be left with a damp structure.
In any building work, most of the cost is in the ground (the foundations and the DPC), which is frustrating as it's the part of the job you'll never see. Bear this in mind and calculate the cost of every project before you decide to go ahead with it.
Finally, people often forget to wear goggles. I was taking out a pane of glass once and a glass splinter went straight into my eye. I could see it sticking out, so I just pulled it out, but it could've been so much worse. That taught me a lesson. I always wear goggles now. DIY is not about looking good.
Permission granted?
Unless you live in a listed building, conservation area or national park, you can paint the exterior of your house any colour your choose. You can carry out repairs to guttering, walls and windows without permission and you can furnish your garden with patios and paths without complaint. Walls and fences under 2m tall don't require planning permission. Decking, however, is another matter. If your deck measures more than 3m from the ground to the top of the balustrade, you'll need planning permission.
If you carry out external work which requires planning permission before you apply for it, your local council has the right to demolish it, so check with them first. See or for more information.


text:
E. Cobham Brewer _PHONE_. Dictionary of Phrase and Fable. 1898.
in Switzerland. The similarity of the word with the name of Pontius Pilate has given rise to the tradition that the Roman Governor, being banished to Gaul by Tiberius, wandered to this mount and threw himself into a black lake on its summit. But Mont Pileatus means the hatted mountain, because it is frequently capped with clouds.
The story goes, that once a year Pilate appears in his robes of office, and whoever sees the ghost will die before the year is out. In the sixteenth century a law was passed forbidding anyone to throw stones in the lake, for fear of bringing a tempest on the country.
There is a town called Pilate in the island of Hispaniola, and a Mont Pilate in France.


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Cité épiscopale d'Albi
Built in the middle of the 11th century, the Pont-vieux (old bridge), 150 metres long, contributed to the urban and commercial development of the town.
In the Middle Ages it included a fortified gate, a chapel and a drawbridge.
From the 14th through to the 18th century there were houses built upon the pillars but these were destroyed when the Tarn burst its banks in 1766. In 1820 the carriageway was redressed and enlarged. The bridge was then given a new brick façade.
Witness to eight centuries of history the bridge was one of the determining factors in the town's prosperity. After the automobile revolution this bridge once again became central to urban life with a large fraction of the town's traffic passing over it each day.
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text:
New research has found that an imaging process used in research labs could detect early-stage lung disease if developed for use in hospitals and clinics.
Researchers from the KTH Royal Institute of Technology in Stockholm examined how a process called phase-contrast X-ray imaging could be used to detect lung disease in humans. In the study titled 'Phase-contrast virtual chest radiography', the research team used a model developed at Duke University that simulates the human chest.
The researchers found that phase-contrast chest radiography could visualise the smallest airways in the lungs, including those less than 2mm wide. The technology can also help to identify lung disease-related obstructions, something that conventional radiography cannot do.
The limitations of conventional imaging
Conventional Phase-contrast imaging used in research labs is limited to imaging centimetre-scale samples of soft tissue. This study has shown that phase-contrast X-ray imaging has the potential to detect lung disease if the technical demands can be engineered for clinical use.
According to the study's lead author, Ilian Häggmark, current chest radiography methods used in clinics and hospitals today can play a role in detecting lung disease, but it is limited by how it generates images.
"Phase-contrast X-ray imaging can extract more information at higher resolution using the same amount of radiation dose as in conventional radiography," said Häggmark.
In conventional radiography, the X-ray beam passes through the body before it is absorbed by different tissues in different amounts. A detector then measures the beam's intensity after filtering through the body. This process is known as attenuation and is the basic mechanism for providing the contrast that forms X-ray images.
The phase-contrast technique allowed clinicians to extract more information from each X-ray beam. Using this technology, clinicians can measure differences in the waveforms of X-rays that pass through a sample. X-ray beams encounter atoms and other structures that can change the position of a wave at any point in relation to a reference wave.
Phase-contrast technology makes it easier to detect lung disease
This information is used to generate an image that enhances structures in the sample. These images can highlight the boundaries of bronchial walls and small airways with higher contrast and better resolution, enabling clinicians to easily identify signs of lung disease.
The researchers have said that moving the detector further away from the patient is key to this method. They also emphasise that developing equipment for imaging larger samples will take time.
"You need an X-ray source with both high power and a small emission spot. Basically, you need bright X-ray sources," said Häggmark.
According to the researchers, promising developments are taking place, but it will take time for these to be ready for human use.
"For now, simulations and virtual clinical trials are the perfect tools to explore what we can do when the source technology is ready," concluded Häggmark.


Do Betta Fish Sleep? [The Complete Guide]
Asides the complexity in the dynamism behind the inhabitation of the male and female betta fish, what else is worth knowing about your betta fish? Well, there are lots of other questions that need to be answered, one of which is the one that is been discussed in this piece. As a new betta fish owner, the thought of a sleeping betta fish might have crossed your mind at some point. So, do betta fish sleep? In this piece, we will be discussing in detail, the facts that surround this phenomenon, and every other thing that's worth discussing.
Do Betta Fish Sleep?
One of the most intelligent species of fish is the betta fish. They are interactive and extremely intelligent, and that's what makes them an interesting pet. They are usually active during the day, but do they sleep? When do they sleep? And how do they sleep? Asides dealing with these questions, we will also talk about some interesting facts about this intelligent water pet.
So, do betta fish sleep? Yes, they do! Just like humans, bettas also need to sleep. But how they sleep is a bit different. Humans are known to be either a heavy sleeper or a light sleeper. However, bettas are known to be a light sleeper. The reason behind betta being light sleepers is not farfetched, this has to do with their natural survival instinct. Imagine bettas been heavy sleepers. In a body of water filled with larger predators, bettas will be snacks for predators every day. Also, bettas are territorials, not wanting to be chased out of their territory, they sleep light to stay conscious in case of a sudden threat. You can 'catch them in the act' if you look long enough. You will notice there are times when your water pet becomes motionless. The entire part of the betta fish stays motionless when they sleep, apart from the gills. When you notice all of these, then it means your betta fish is asleep.
Apart from being one of the most intelligent and interactive species of fish, unlike the scenery of a school of fish with choreographed movements. Bettas are loners, they don't live by doing the exact thing others do. They are unique and interestingly, aren't bound by any of these rules. All of these have subconsciously helped shape their personality. A profile that has made them one of the sorted after water pets out there.
You can buy a sleeping bed for your betta fish from Amazon!
What Do They Look Like When They Sleep?
One of the 'surest' ways to know your betta is asleep is when they become motionless. But, one factor that plays a major role is the time of the day. When they are motionless at night, it simply means that he's taking a nap. This also happens during the day. If the body stays motionless while the gills are active, coupled with breathing in and out, it means your betta fish is asleep. Some betta owners also claim that the fish loses some of his colors when he's asleep, there isn't a proof to that claim. But you can always keep an eye out for that. However, as funny as this sounds, don't look at their eyes to catch them sleeping, bettas don't have eyelids, just like most (if not all fishes). So, whether or not, they are asleep, bettas will always open their eyes.
How To Tell If Your Betta Fish Is Asleep?
Reiteratively, when your betta stays motionless for a very long time in the tank, then there's a high probability that your fish is asleep. Especially when this happens during the night. but do they sleep on their sides? Basically, when this happens, a lot of new better owners feel terrified, because they usually think that the fish is dead or sick. Well, bettas do sleep on their side. You can check closely to be sure, but more often than not when this happens, its because he (your betta fish) is asleep. But, when he stays that way for a very long time, it could mean something else, something bad. It could be a sign of illness or in some cases, death.
But there's a caveat to this, bettas are known to lay on their sides when they sleep at the bottom of the tank. Not just that, they are also known to sleep under leaves, between rock, or anywhere else that feels comfy. They may also remain motionless for a very long time.
When Do Betta Fish Sleep?
Next to what and how is when they sleep. So, what time does this usually happen the most? Betta fish sleep during the night and take naps during the day. If you want your fish to get into better sleeping patterns, you should turn off the light when its nighttime. Turning your light off during the night helps your fish get into a proper sleeping pattern. This way, your fish will be able to distinguish between daytime and nighttime. Just like humans, bettas hardly fall asleep when the light is on. Some of the other things to avoid during this period is poking at your betta and or tapping on the glass.
Is Your Betta Asleep?
Even though you've been given the signs to look out for when he is asleep, it is also better to always check on your fish in case it starts to act weird. You can check on it at night before you go to bed, or while you are awake in the middle of the night. When you do this often, you will be able to spot the difference in the patterns. You will be able to know if he is sleeping or signs of old age or illness. When you notice your betta is motionless during the day, the gill movement is a tell – sign that it's still alive. But in a situation where all the parts of the fish remain motionless 'including' the gills, then it means your betta is dead. But, before jumping to a conclusion, open your tank and take it ours with a fishnet. Check for signs of wounds or illness. Sometimes, when they get sick, you'll hardly see them moving.
Tips to Help Your Betta Fish Sleep Well:
So, how do you ensure your betta sleeps well? there are certain things you could do to help your betta have a nice nap. When your betta rests well, it usually makes for a happier betta fish. One of the best gifts you can give your betta fish is long hours of darkness.
If you won't be able to keep up with this (turning the lights off), you should get an aquarium timer, with the timer will help turn on your tank lights off at night then turning it back on during the daytime. When they are having their nap during the daytime, they prefer shady spots. How do you create shady spots for your betta? Firstly, when setting up your tank, always choose a shady spot. Wherever you decide to put it, make sure it is not exposed to direct sunlight. Get floating plants, you could also get tall plants in case you can't get floating plants. But, make sure the plants you've selected are not toxic or harmful to bettas. With these plants, you will be able to block out sunlight. Install decorations in their tank; from bridges, caves to tunnels, these decorations will help create the shady spots your betta fish needs.
Preferably, when setting up your betta tank, consider the sleeping spots. Ultimately, this will help your betta fish sleep well, and of course, when your betta sleeps well, it makes for a healthy water pet. However, your betta shouldn't sleep all the time. If your betta fish sleeps too much, it's usually due to any of these reasons:
4 Reasons Why Your Betta Fish Sleeps Too Much:
· Your tank set up is boring.
What hits your mind when you think of excess sleep? Boredom! When your tanks have no decorations and are small in size, then there is nothing to do but to sleep off. Some of the things you should consider asides shady spots are the size of your tank and toys. You can install toys including a betta mirror. Doing all of these will help optimize your betta fish's sleeping pattern. So, why he is not asleep, he gets to do something fun. We recommend changing the décor regularly to give your betta something else to do.
· Your Aquarium is not getting enough light.
Yes, we pointed out the fact that bettas sleep less during the daytime. The goal is not to let your fish sleep all the time. Your main objective is to optimize their routines and sleep when they should. So, your betta should get 9 to 12 hours of light daily.
· The betta tank is too cold or hot.
When there is a feeling of extreme temperature in the tank, it's not healthy for your betta. Bettas are known to thrive in water temperature that's between 78 to 82degree Fahrenheit. Anything outside this range will make your betta weak and sleepy. Check the water temperature of your betta tank regularly. Also, make sure the thermometer is accurate.
· Your betta is ill.
Just like humans, when bettas are ill, they sleep a lot. One of the reasons why your betta may be sleeping a lot more than he should be because he is sick. What are some of the common illnesses in bettas?
These illnesses include:
 - Popeye
 - Dropsy
 - Mouth fungus
 - Hemorrhagic
 - Fin/tail rot
 -


Dirac Matrices and Lorentz Spinors
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1 Dirac Matrices and Lorentz Spinors Background: In 3D, the spinor j = 1 representation of the Spin3) rotation group is constructed from the Pauli matrices σ x, σ y, and σ k, which obey both commutation and anticommutation relations σ i, σ j = iɛ ijk σ k and {σ i, σ j } = δ ij 1. 1) Consequently, the spin matrices S = i σ σ = 1 σ ) commute with each other as angular momenta, S i, S j = iɛ ijk S k, so they represent the generators of the rotation group. Moreover, under finite rotations Rφ, n) represented by MR) = exp iφn S ), 3) the spin matrices transform into each other as components of a 3 vector, M 1 R)S i MR) = R ij S j. 4) In this note, I shall generalize this construction to the Dirac spinor representation of the Lorentz symmetry Spin3, 1). Dirac Matrices are 4 anti-commuting 4 4 matrices γ µ, γ µ γ ν + γ ν γ µ = g µν ) The specific form of these matrices is not important as long as they obey the anticommutation relations 5) and different books use different conventions. In my class I shall follow the same convention as the Peskin & Schroeder textbook, namely the Weyl convention where in block notations ) ) 0 γ σ =, γ =. 6) 1 0 σ 0 Note that the γ 0 matrix is hermitian while the γ 1, γ, and γ 3 matrices are anti-hermitian. 1
2 Lorentz spin matrices. Given the Dirac matrices obeying the anticommutation relations 5), we may define the spin matrices as S µν = S νµ def = i 4 γµ, γ ν. 7) These matrices obey the same commutation relations as the generators Ĵµν = Ĵνµ of the continuous Lorentz group. Moreover, their commutation relations with the Dirac matrices γ µ are similar to the commutation relations of the Ĵµν with a Lorentz vector such as ˆP µ. Lemma: γ λ, S µν = ig λµ γ ν ig λν γ µ. 8) Proof: Combining the definition 7) of the spin matrices as commutators with the anticommutation relations 5), we have γ µ γ ν = 1 {γµ, γ ν } + 1 γµ, γ ν = g µν is µν. 9) Since the unit matrix commutes with everything, we have X, S µν = i X, γµ γ ν for any matrix X, 10) and the commutator on the RHS may often be obtained from the commutators or anticommutators: Leibniz rules for the A, BC = A, BC + BA, C = {A, B}C B{A, C}, {A, BC} = A, BC + B{A, C} = {A, B}C BA, C. 11) In particular, γ λ, γ µ γ ν = {γ λ, γ µ }γ ν γ µ {γ λ, γ ν } = g λµ γ ν g λν γ µ 1) and hence Quod erat demonstrandum. γ λ, S µν = i γλ, γ µ γ ν = ig λµ γ ν ig λν γ µ. 13)
3 Theorem: The S µν matrices commute with each other like Lorentz generators, S κλ, S µν = ig λµ S κν ig κν S µλ ig λν S κµ + ig κµ S νλ. 14) Proof: Again, we use the Leibniz rule and eq. 9): γ κ γ λ, S µν = γ κ γ λ, S µν + γ κ, S µν γ λ = γ κ ig λµ γ ν ig λν γ µ) + ig κµ γ ν ig κν γ µ) γ λ = ig λµ γ κ γ ν ig κν γ µ γ λ ig λν γ κ γ µ + ig κµ γ ν γ λ = ig λµ g κν is κν) ig κν g λµ + is λµ) ig λν g κµ is κµ) + ig κµ g λν + is λν) 15) = g λµ S κν g κν S λµ g λν S κµ + g κµ S λν, and hence S κλ, S µν = i γ κ γ λ, S µν = ig λµ S κν ig κν S µλ ig λν S κµ + ig κµ S νλ. 16) Quod erat demonstrandum. In light of this theorem, the S µν matrices represent the Lorentz generators Ĵµν in a 4-component spinor multiplet. Finite Lorentz transforms: Any continuous Lorentz transform a rotation, or a boost, or a product of a boost and a rotation obtains from exponentiating an infinitesimal symmetry X µ = X µ + ɛ µν X ν 17) where the infinitesimal ɛ µν matrix is antisymmetric when both indices are raised or both lowered), ɛ µν = ɛ νµ. Thus, the L µ ν matrix of any continuous Lorentz transform is a matrix exponential L µ ν = expθ) µ ν δ µ ν + Θ µ ν + 1 Θµ λ Θλ ν Θµ λ Θλ κθ κ ν + 18) of some matrix Θ that becomes antisymmetric when both of its indices are raised or lowered, Θ µν = Θ νµ. Note however that in the matrix exponential 18), the first index of Θ is raised 3
4 while the second index is lowered, so the antisymmetry condition becomes gθ) = gθ) instead of Θ = Θ. The Dirac spinor representation of the finite Lorentz transform 18) is the 4 4 matrix M D L) = exp i Θ αβs αβ). 19) The group law for such matrices L 1, L SO + 3, 1), M D L L 1 ) = M D L )M D L 1 ) 0) follows automatically from the S µν satisfying the commutation relations 14) of the Lorentz generators, so I am not going to prove it. Instead, let me show that when the Dirac matrices γ µ are sandwiched between the M D L) and its inverse, they transform into each other as components of a Lorentz 4 vector, M 1 D L)γµ M D L) = L µ νγ ν. 1) This formula makes the Dirac equation transform covariantly under the Lorentz transforms. Proof: In light of the exponential form 19) of the matrix M D L) representing a finite Lorentz transform in the Dirac spinor multiplet, let s use the multiple commutator formula AKA the Hadamard Lemma ): for any matrices F and H, exp F )H exp+f ) = H + H, F + 1 H, F, F H, F, F, F +. ) In particular, let H = γ µ while F = i Θ αβs αβ so that M D L) = exp+f ) and M 1 D L) = exp F ). Consequently, MD 1 L)γµ M D L) = γ µ + γ µ, F + 1 γ µ, F, F γ µ, F, F, F + 3) where all the multiple commutators turn out to be linear combinations of the Dirac matrices. 4
5 Indeed, the single commutator here is γ µ, F = i Θ αβ γ µ, S αβ = 1 Θ αβ g µα γ β g µβ γ α) = Θ αβ g µα γ β = Θ µ λ γλ, 4) while the multiple commutators follow by iterating this formula: γ µ, F, F = Θ µ λ γ λ, F = Θ µ λ Θλ νγ ν, γ µ, F, F, F = Θ µ λ Θλ ρθ ρ νγ ν,.... 5) Combining all these commutators as in eq. 3), we obtain MD 1 γµ M D = γ µ + γ µ, F + 1 γ µ, F, F γ µ, F, F, F + = γ µ + Θ µ νγ ν + 1 Θµ λ Θλ νγ ν Θµ λ Θλ ρθ ρ νγ ν + ) = δ ν µ + Θ µ ν + 1 Θµ λ Θλ ν + 6 1Θµ λ Θλ ρθ ρ ν + γ ν 6) L µ νγ ν. Quod erat demonstrandum. Dirac Equation The Dirac spinor field Ψx) has 4 complex components Ψ α x) arranged in a column vector Ψ 1 x) Ψ Ψx) = x


text:
Metal Oxide Catalyst for Methyl Ethyl Ketone Production via One-Step Oxidation of n-Butane
Dr. Manhua Mandy Lin, Principal Investigator
DOE Grant No. DE-FG02-03ER83652
Methyl ethyl ketone (MEK) is a commodity chemical in high demand with an annual production of about 675 million pounds in the U.S., of which 87 % is produced via the energy consuming three-step sec-butyl alcohol route from the relatively expensive starting material, 1-butene, while generating corrosive and toxic wastes. To simultaneously address the cost, energy, and environmental issues, this project aims at exploring and developing a one-step catalytic process for the manufacturing of MEK from n-butane, a cheap and abundant component of natural gas. This n-butane process is a gas-phase selective oxidation using air as the oxidant. The Phase I is to demonstrate the feasibility of this n-butane process by achieving a reasonable n-butane conversation and MEK selectivity. The Phase II objective will be to achieve industrial-significant n-butane conversion and MEK selectivity, which would warrant further commercial development.
Commercial Applications and Other Benefits: If the n-butane-to-MEK process is successfully developed and implemented to replace the current commercial sec-butyl alcohol process, the cost saving on the feedstock could be as high as 60 %. A significant energy saving as well as waste reduction are also anticipated.


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Pride - Definition
The definition of: Pride is below.
There are 1 syllables in the word Pride.
What rhymes with Pride?
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Definition of: Pride
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Standard Definition
[n] unreasonable and inordinate self-esteem (personified as one of the deadly sins)
[n] the trait of being spurred on by a dislike of falling below your standards
[n] a feeling of self-respect and personal worth
[n] satisfaction with your (or another's) achievements; "he takes pride in his son's success"
[n] a group of lions
[v] pride or congratulate (oneself) for an achievement
[v] be proud of; "He prides himself on making it into law school"
[v] be proud of; "She prides herself on her son"
congratulate - (4 syllables), congratulate - (4 syllables), plume - (1 syllables), preen - (1 syllables), pridefulness - (3 syllables), superbia - (4 syllables)
Misc. Definitions
\Pride\, n. [Cf. AS. lamprede, LL. lampreda, E. lamprey.] (Zo["o]l.) A small European lamprey ({Petromyzon branchialis}); -- called also {prid}, and {sandpiper}.
\Pride\, n. [AS. pr[=y]te; akin to Icel. pr[=y][eth]i honor, ornament, pr??a to adorn, Dan. pryde, Sw. pryda; cf. W. prydus comely. See {Proud}.]
1. The quality or state of being proud; inordinate self-esteem; an unreasonable conceit of one's own superiority in talents, beauty, wealth, rank, etc., which manifests itself in lofty airs, distance, reserve, and often in contempt of others. Those that walk in pride he is able to abase. --Dan. iv. 3
7. Pride that dines on vanity sups on contempt. --Franklin.
2. A sense of one's own worth, and abhorrence of what is beneath or unworthy of one; lofty self-respect; noble self-esteem; elevation of character; dignified bearing; proud delight; -- in a good sense. Thus to relieve the wretched was his pride. --Goldsmith. A people which takes no pride in the noble achievements of remote ancestors will never achieve anything worthy to be remembered with pride by remote descendants. --Macaulay.
3. Proud or disdainful behavior or treatment; insolence or arrogance of demeanor; haughty bearing and conduct; insolent exultation; disdain. Let not the foot of pride come against me. --Ps. xxxvi. 1
1. That hardly we escaped the pride of France. --Shak.
4. That of which one is proud; that which excites boasting or self-gratulation; the occasion or ground of self-esteem, or of arrogant and presumptuous confidence, as beauty, ornament, noble character, children, etc. Lofty trees yclad with summer's pride. --Spenser. I will cut off the pride of the Philistines. --Zech. ix.
6. A bold peasantry, their country's pride. --Goldsmith.
5. Show; ostentation; glory. Pride, pomp, and circumstance of glorious war. --Shak.
6. Highest pitch; elevation reached; loftiness; prime; glory; as, to be in the pride of one's life. A falcon, towering in her pride of place. --Shak.
7. Consciousness of power; fullness of animal spirits; mettle; wantonness; hence, lust; sexual desire; esp., an excitement of sexual appetite in a female beast. [Obs.] {Pride of India}, or {Pride of China}. (Bot.) See {Margosa}. {Pride of the desert} (Zo["o]l.), the camel. Syn: Self-exaltation; conceit; hauteur; haughtiness; lordliness; loftiness. Usage: {Pride}, {Vanity}. Pride is a high or an excessive esteem of one's self for some real or imagined superiority, as rank, wealth, talents, character, etc. Vanity is the love of being admired, praised, exalted, etc., by others. Vanity is an ostentation of pride; but one may have great pride without displaying it. Vanity, which is etymologically ''emptiness,'' is applied especially to the exhibition of pride in superficialities, as beauty, dress, wealth, etc.
\Pride\, v. t. [imp. & p. p. {Prided}; p. pr. & vb. n. {Priding}.] To indulge in pride, or self-esteem; to rate highly; to plume; -- used reflexively. --Bp. Hall. Pluming and priding himself in all his services. --South.
\Pride\, v. i. To be proud; to glory. [R.]


Italian Navy
Home Up German Airforce British Army German navy Italian Navy Russian Navy Belgian Army French Air Force JASDF
Ships of the Italian Navy:
Guiseppe Garibaldi class VSTOL aircraft carrier
The flagship of the Italian Navy is the aircraft carrier MM Garibaldi, built by Fincantieri of Genoa and commissioned in 1985. Garibaldi (C551) is classed as a CVS - Aircraft Carrier ASW (Anti-submarine Warfare). The ship is capable of carrying 18 helicopters or an air squadron of vertical or short take off and landing (VSTOL) aircraft. The carrier can carry out anti-submarine warfare, command and control of naval and aero-naval forces, area surveillance, convoy escort, commando transportation, and fleet logistic support.
Vittorio Veneto helicopter cruiser
The Vittorio Veneto is a purpose built helicopter cruiser that followed from the design of the Andrea Doria class of the 1950s. The addition of a second deck gave her a much greater helicopter capacity. A large central lift is set immediately aft of the superstructure and two sets of fin stabilizers make her a very steady helicopter platform. She has gone through two major refits in 1981 and 1984 which have upgraded her weaponry and radars. Her previous role of Italian flagship was handed over to the carrier Guiseppe Garibaldi in 1995.
Luigi Durand de la Penne class destroyers
The Durand De La Penne Class destroyers were built by Fincantieri for the Italian Navy. The first of class ship, MM Luigi Durand De La Penne (D560), and the second, MM Francesco Mimbelli (D561), were commissioned in 1993. The Durand De La Penne destroyers are 5000 ton multi-role warships able to perform anti-air defence for protecting task forces and convoys, anti-submarine and anti-surface warfare operations, assistance during landing operations and coastal bombardment
Audace class destroyers
Ordered in the late 1960s, these two ships were derived from the Impavido class, but incorporated a number of important advances. A larger, more seaworthy hull was adopted and most of the weaponry is of Italian design. Armament: 1 Mk13 launcher (40 SM-1MR), 8 Otomat SSM, 1 8-cell Albatros SAM (Aspide missiles), 1 5/54 DP, 4 76 mm OTO DP, 2 triple 12.75 inch torpedo tubes.
Maestrale class frigates
An enlarged and much improved Lupo design. The most notable difference is the larger hangar housing two helicopters and the more modern weaponry and sensors. Armament: 4 Otomat SSM, 8-cell Albatros SAM (24 Aspide missiles), 1 5/54 DP, 2 dual 40 mm AA, 2 21 inch torpedo tubes, 2 triple 12.75 inch torpedo tubes
Lupo class light frigates
This class was a major improvement over the previous Alpino class frigates, with a more "multirole" configuration and more modern and powerful weaponry. Designed for all around naval duties. These ships make excellent escorts with their fast speeds and effective weaponry.
Artigliere (modified Lupo) class patrol frigates
Armament: 8 Otomat SSM, 1 8-cell Albatros SAM (Aspide missiles), 1 5/54 DP, 2 dual 40 mm AA These Lupo-class frigates were built for Iraq in the early 1980's, but never delivered. They were taken over for the Italian Navy in 1992. They have been stripped of ASW systems and serve as patrol vessels.
Minerva class large corvettes
This class was built to replace the older corvettes of the DeCristofaro and Albatros
class). While designated frigates and performing many of the jobs of them, these ships are perhaps best described as large corvettes. Fitted for but not installed with Teseo SSMs, these ships are used mainly for patrol and escort duties
Primo Longobardo class coastal submarines
Displacement: 1,862 tons submerged Dimensions: 66.35 x 6.83 x 6 meters (217.5 x 22.5 x 19.5 feet) Propulsion: Diesel-electric, 3 diesels, 1 shaft, 3650 shp, 19 knots Crew: 50 Sonar: IPD-705 active/passive, MD 100S passive flank Armament: 6 21 inch torpedo tubes (12 torpedoes) Depth: 300 meters
Salvatore Pelosi class coastal submarines
Displacement: 1,662 tons submerged Dimensions: 64.36 x 6.83 x 5.66 meters (211 x 22.5 x 18.5 feet) Propulsion: Diesel-electric, 3 diesels, 1 shaft, 4,270 shp, 19 knots Crew: 50 Sonar: IPD-703 active/passive, MD 100S passive flank, M5 intercept Armament: 6 21 inch torpedo tubes (12 torpedoes) Depth: 300 meters
Nazario Sauro class coastal submarines
Displacement: 1,637 tons submerged Dimensions: 63.85 x 6.83 x 5.7 meters (209.5 x 22.5 x 18.5 feet) Propulsion: Diesel-electric, 3 diesels, 1 shaft, 4,270 shp, 19 knots Crew: 49 Sonar: IPD-70/S passive, M5 intercept Armament: 6 21 inch torpedo tubes (12 torpedoes) Depth: 300 meters
San Giorgio class small dock landing ships
The ships provide roll-on/roll-off landing capability for land embarkation; air lift through the use off high capacity aircraft such as Chinook-type helicopters; and transportation by sea to shore, using the ship's own systems and landing ships for landing on unprepared shores.
Lerici class minehunters
Displacement: 520 tons full load Dimensions: 49.98 x 9.56 x 2.7 meters (164 x 31 x 9 feet) Propulsion: 1 diesel, 1 shaft, 1,840 bhp, 15 knots Crew: 47 Sonar: SQQ-14A minehunting (being replaced by SSN-7M + Type 2048) Armament: 1 20 mm
Etna small replenishment oiler
Stromboli class small fleet oilers
Displacement: 8,706 tons full load Dimensions: 129 x 18 x 6.5 meters (423 x 59 x 21 feet) Propulsion: 2 diesels, 1 shaft, 11,200 bhp, 19.5 knots Crew: 124 Aviation: aft helicopter deck Cargo: 1,370 tons fuel oil, 2,830 tons diesel, 480 tons aviation fuel, 200 tons misc stores Fire Control: SPG-70 gun control Armament: 1 76mm/62 DP, 2 20 mm
Harrier VSTOL carrier fighter and bomber
The Harrier II Plus is equipped with a multi-mode radar and has beyond-visual-range missile capability. The italian navy has 16 harriers.
Agusta Bell AB-212 ASW and Sikorsky SH-3D
There both used in the italian navy and on the aircraft carrier and assauslt ships main use for these helicopters is for transportation for militarty troops and material.
Brequet Atlantic
The Atlantique ATL3 maritime patrol aircraft, successor to the Atlantique ATL1 and ATL2, incorporates an enhanced weapon system with a maximum 9,000 kg payload, new technology engines, glass cockpit and sophisticated avionics and sensors. The ATL1, selected as the NATO Long Range Maritime Patrol Aircraft, entered service in 1966 and remains in service
NH 90
The NATO Frigate Helicopter (NFH) is one of two versions of the NH90 twin engine multirole helicopter being developed by NH Industries. The other version is the NH90 TTH Tactical Transport Helicopter.The primary missions of the NH90 NFH helicopter are in the autonomous anti submarine warfare (ASW) and anti-surface ship warfare (AsuW) role.


text:
The introduction of the Metadata extension within the Solana ecosystem significantly enhances the capabilities of token issuers by allowing them to attach customizable key-value pairs directly to a Mint Account. This extension fundamentally broadens the scope of what can be achieved with tokens, particularly in domains such as gaming, by enabling the embedding of custom metadata within each token. Such an advancement opens up myriad possibilities for how tokens can be utilized, interacted with, and represented.
Token Metadata Interface
The Token Metadata Interface standardizes the procedure for adding metadata to tokens, offering a defined structure and a set of instructions for managing metadata. This interface can be implemented by any program, affording developers the flexibility to craft bespoke Metadata Programs. This universal interface ensures compatibility across the Solana ecosystem, allowing wallets, decentralized applications (dApps), and other on-chain programs to seamlessly access and interact with token metadata.
Metadata Interface Fields
The interface delineates a standard format for the
TokenMetadata struct, which includes fields for basic token information such as name, symbol, and URI, in addition to an
additional_metadata field for custom key-value pairs. This design permits the inclusion of extensive and varied data about tokens, thus accommodating a wide range of use cases.
Metadata Interface Instructions
The interface specifies a concise set of instructions for interacting with token metadata:
- Initialize: Sets up the initial metadata fields.
- UpdateField: Allows for the modification of existing fields or the addition of new key-value pairs.
- RemoveKey: Facilitates the removal of key-value pairs from the
- UpdateAuthority: Enables the change of authority for metadata modification.
- Emit: Ensures the metadata can be emitted in the standard
TokenMetadataformat, thereby supporting diverse account data storage formats.
To leverage the Metadata extension, developers initiate by creating a Mint Account that enables both the MetadataPointer and TokenMetadata extensions. This approach consolidates metadata management into a single account, streamlining the process of metadata addition and modification.
The process involves several key steps:
- Mint Account Setup: Define the properties of the Mint Account, including the metadata to be stored.
- Account and Extension Initialization: Calculate the required account size and lamports for rent exemption, create the Mint Account, and initialize the necessary extensions.
- Metadata Management: Implement the instructions to add, update, and remove metadata as needed.
Advantages and Opportunities
The Metadata extension presents numerous advantages and opportunities for developers:
- Enhanced Token Utility: By embedding custom metadata directly into tokens, developers can create more complex and engaging token-based applications and games.
- Ecosystem Standards: The extension fosters the development of new standards for using metadata on-chain, encouraging collaboration within the developer community to explore innovative uses of token metadata.
- Simplified Process: Directly storing metadata on a Mint Account simplifies the metadata management process, reducing complexity and enhancing efficiency.


This is an important test that is typically used to monitor foetal health in pregnant women.
Venous blood
1 tests included
5 days turnaround
About Oestriol
What is oestriol?
Oestriol is one of the three main naturally produced oestrogen hormones, along with oestradiol and oestrone. It is typically present in very low concentrations for most of a woman's life, increasing drastically in the placenta during pregnancy. Free oestriol levels can be used as an indicator of foetal health, with lower than normal blood levels during pregnancy potentially indicating a chromosome disorder such as Down's Syndrome.
Why take the test?
This test measures the level of oestriol in the blood. It is typically used to monitor foetal health in pregnant women.
What's tested
How it works
Purchase your Kit
Take your test and post
Get results directly to your dashboard


see that correctly, the current implementation of all_paths() for digraphs does the former, but the path-semigroup relies on the latter.
So, let me re-formulate my question to you.
 1. Do you want a new method called, say, DiGraph.all_quiver_paths() or DiGraph.all_arrow_sequences() that returns what the path semigroup needs?
What about DiGraph.all_paths(edges=True) ?
 1. Do you want me to replace the current DiGraph.all_paths() so that it returns what the path semigroup needs?
You are a free man and if I complain a lot I don't own the graph code. I just care about it. This all_paths function has probably been created because somebody needed it, and if you just replace it with what you need instead we are going nowhere.
 1. Do you want that the path semigroup computes its underlying data on its own, without introducing a new method of DiGraph?
Well, you are free to do whatever you want with the code of this semigroup. Right now the all_paths method returns a list of paths (be it with vertices or edges), and if you want to do anything fast with your semigroup you probably need to implement your own data structure to store it better.
If it is a data structure which is efficient to store path independently of what you do with it semigroup structure, well, then it should probably be called AllPaths or something rather than semigroup. Then, your semi-group can use this data structure, by class inheritance or anything you like.
I'd be surprised if you answer "yes" to 1., and shocked if you replied "yes" to 2. Thus, I suppose you prefer 3., but perhaps I am mistaken.
I thought 2) was a joke, but I answered it seriously just in case. The answer to 3 depends on what you do with the paths : how do you plan on storing them ? A list is probably the worst you can do ^^;
Nathann
comment:168 in reply to: ↑ 167 ; follow-up: Changed 4 years ago by SimonKing
Hi Nathann,
Replying to ncohen:
What about DiGraph.all_paths(edges=True) ?
Yes, good idea!
I thought 2) was a joke, but I answered it seriously just in case. The answer to 3 depends on what you do with the paths : how do you plan on storing them ? A list is probably the worst you can do ^^;
In the current code, it is stored in a (Python) list, and I totally agree that this is bad. But I want to see this code move forward, and the code has been refactored often enough.
So, I want a preliminary but slow version (that apparently is useful to people, or otherwise Jim Stark had not provided the code) and then replace it with something faster.
I have an implementation using two different kinds of storing it as *long, in compressed form. In both implementations, concatenation, comparison and sub-path test are fast enough for me...
But this will be on a new ticket, since otherwise I don't see a chance of progress here.
comment:169 in reply to: ↑ 168 ; follow-up: Changed 4 years ago by ncohen
Yoooooooo !
In the current code, it is stored in a (Python) list, and I totally agree that this is bad.
O_o
What can you do with the *list* of paths ? Even checking whether a path is in the list is probably faster by using the graph itself O_o
But I want to see this code move forward, and the code has been refactored often enough.
'f you say so...
So, I want a preliminary but slow version (that apparently is useful to people, or otherwise Jim Stark had not provided the code) and then replace it with something faster.
Are you open to "bets" on the meaning of "later" ? :-P
I have an implementation using two different kinds of storing it as *long, in compressed form. In both implementations, concatenation, comparison and sub-path test are fast enough for me...
Oh. It is already implemented. Then I guess the "later" may not be too far.
But this will be on a new ticket, since otherwise I don't see a chance of progress here.
ts'up to you !
Nathann
comment:170 in reply to: ↑ 169 Changed 4 years ago by SimonKing
Hi Nathann!
Replying to ncohen:
What can you do with the *list* of paths ? Even checking whether a path is in the list is probably faster by using the graph itself O_o
You misunderstood: I don't intend to keep a list containing paths. But currently, a path is implemented as a list of edges, and an edge is a triple "startpoint, endpoint, label". Instead, a path should be a *long, at least in my applications.
Are you open to "bets" on the meaning of "later" ? :-P
A month, maybe two. It must not be much longer, since my grant is centred around an implementation of Faugère's F5 algorithm, generalised for path algebra quotients (punch line: in contrast to other famous Gröbner basis algorithms, F5 can compute minimal generating sets for modules).
So, I have a financial interest in having a decent implementation of path algebras soon. And in fact I have something, but it should be rebased on top of this ticket (currently, my own implementation is independent of this ticket, which means there is some code duplication). Best regards,
Simon
comment:171 follow-up: Changed 4 years ago by SimonKing
Nathann, I have some questions concerning all_paths.
I just notice: There is the method all_paths_iterator, and I expected it to be used in a generic implementation of all_paths. But in fact, the generic all_paths relies on neighbor_out_iterator (for digraphs, at least). Why is that?
And in particular: Would neighbor_out_iterator be the correct place to change the behaviour of the all_paths method (depending on an optional argument, of course)?
comment:172 in reply to: ↑ 171 ; follow-up: Changed 4 years ago by ncohen
Hello !
Nathann, I have some questions concerning all_paths.
Oh ?
I just notice: There is the method all_paths_iterator, and I expected it to be used in a generic implementation of all_paths. But in fact, the generic all_paths relies on neighbor_out_iterator (for digraphs, at least). Why is that?
Answer #1: All I know about this code is that I do not like it. Nobody should enumerate paths in Python.
Answer #2: Let me read that code...
Well, I have NO idea why this thing is implemented twice. One function should be more than enough, and I do not yet why we have both a list version and an iterator version. The iterator version should be sufficient, we can wrap the call with list if needed, so well... O_o
Those things should probably be merged. I don't like to see heaps involved in the code of all_paths_iterator though (which is only implemented for digraphs, for some reason). Plus I have absolutely NO idea why heaps are involved there. A list should be sufficient O_o
And in particular: Would neighbor_out_iterator be the correct place to change the behaviour of the all_paths method (depending on an optional argument, of course)?
Hmmmmm... What would you want to change in neighbor_out_iterator ? My secret hope is that whatever you want neighbor_out_iterator to give you there is already another way to obtain it, for I don't really want to add anything smart in this function which we already try to make FAST. Tell me, and we'll find a way.
Nathann
comment:173 follow-up: Changed 4 years ago by SimonKing
... or perhaps add a new method neighbor_out_arrows_iterator, that is to be used by all_paths depending on an optional parameter.
PS: I don't think an all_paths method makes any sense (to people using cyclic graphs, at least). In general, you'd have an infinite list, hence, an iterator is the best you can hope for.
comment:174 in reply to: ↑ 173 ; follow-up: Changed 4 years ago by ncohen
Hellooooo !
... or perhaps add a new method neighbor_out_arrows_iterator, that is to be used by all_paths depending on an optional parameter.
list(digraphs.Circuit(5).edge_iterator(1)) ?
PS: I don't think an all_paths method makes any sense (to people using cyclic graphs, at least). In general, you'd have an infinite list, hence, an iterator is the best you can hope for.
Paths. Not Walks. Paths do not self-intersect.
This being said, an iterator *IS* enough.
Nathann
Last edited 4 years ago by ncohen (previous) (diff)
comment:175 in reply


1. Keystone Security Monitor
The security monitor (SM) is trusted software that runs in M-mode, and forms the trusted computing base (TCB) in Keystone system. The SM is the most important software in Keystone as it provides most of the security guarantees. The SM provides the following functionality:
 1. Memory Isolation using RISC-V PMP
 2. Remote Attestation (Signatures and measurement)
 3. Enclave Thread Management
 4. System PMP Synchronization
 5. Side-Channel Defenses
Version 0.1 only implements 1, 2, and 3, supporting single-threaded enclave.
The security monitor must be verified by the root of trust in hardware before being trusted. After the root of trust measures the SM it generates a keypair for remote attestation, signs the public key, and then continues booting. See Chain of Trust for details.
The OS and enclaves may call SM functions using the supervisor binary interface (SBI), which is implemented in RISC-V environment calls (i.e., ecall instruction). See SBI Documentation for details.
1.1. Specific platforms
1.2. PMP Internals
PMP allows for N (platform defined) entries, which are configured using a config (cfg) and address (addr) register each. There are further details available in the RISC-V specification section 3.6.
In Keystone we refer to the section of memory that an enclave uses as a region and each region is defined by a PMP entry.
1.3. Memory Isolation using RISC-V PMP
The SM currently consumes two PMP entries for its own uses (i.e., security monitor memory and untrusted memory). Each of the remaining PMP entries may be consumed by one active enclave each.
To understand how the SM utilizes PMP, we need to know several properties of RISC-V PMP:
 1. Prioritized by Index
 PMP entries are statically priortized by their index, with a check stopping at the highest priority matching. Indices run from 0..N (where N is platform defined), with 0 having the highest priority, and N having the lowest. Thus, the access permissions to a physical address should be of the lowest-index PMP entry among the matched ones.
 2. Default Deny
 If no PMP entry matches with an address, the memory access will be rejected by default.
 3. Dynamically Configurable by M-mode
 M-mode can write to PMP CSRs during runtime to define PMP entries dynamically. A TLB flush is required after reconfiguration.
 4. Addressing Modes
 PMP supports two addressing modes: naturally-aligned power of two (NAPOT), or top-of-range (TOR). TOR consumes adjacent PMP entry's address register for the bound address to allow shared boundaries efficiently. Ex: Two ranges of 0-2048 and 2048-4096 uses 3 entries, 0, 2048, 4096.
At the very beginning of the boot process, physical memory is not accessible by U- or S-modes because of property 2 as shown in the diagram below.
For ease of understanding, we denote PMP entries as pmp[i] where i is an index.
There are N PMP entries.
-: inaccessible (NO_PERM), =: accessible (ALL_PERM)
pmp[1:N] | | : undefined
The SM sets the first PMP entry to cover the address range containing itself (0x80000000-0x80200000), and sets all permission bits to 0. The SM then sets the last PMP entry to cover the entire DRAM and sets all permission bits to 1, allowing the OS to access the rest of the memory and start booting. Because of the property 1, the net result will be as follows:
pmp[0] |-------| | : SM memory
pmp[others] | | : undefined
When the SM creates an enclave, it will assign a PMP entry to the enclave to protect its memory from other U-/S-mode software.
pmp[1] | |---------| | : enclave memory
pmp[others] | | : undefined
net result |-------|======|---------|===============|
When the SM enters the enclave (executes the enclave), it flips the permission bits of the enclave's PMP entry and the last PMP entry. In addition, Keystone allows the OS to allocate an additional contiguous memory region in the OS memory space so that the enclave can use it as a communication buffer. The buffer is called untrusted shared buffer.
pmp[1] | |=========| | : enclave memory
pmp[others] | | : undefined
pmp[N] | |==| | : untrusted shared buffer
net result |-------|------|=========|-------|==|----|
When the SM exits the enclave, it simply flips the permission bits back. When the SM destroys an enclave, it clears the PMP entry so that other enclaves can use it.
1.4. Remote Attestation
The goal of remote attestation is to prove to a remote client that the enclave contains the program expected, and is running on hardware that is trusted. In Keystone this involves a few cryptographic operations including ECDSA signature and SHA-3 hash.
For more detail about the remote attestation process, see Remote Attestation.
1.5. Enclave Context Management
The Keystone SM manages enclave context (e.g., general purpose registers, trap vector, etc) and the status of each hardware thread. When an enclave enters and exits, the SM performs the following steps to switch between trusted and untrusted contexts:
 1. Update thread status
 2. Save the previous context
 3. Restore the next context
 4. Flip PMP permissions
 5. Flush TLB
1.6. Building platform specific modules
You can re-configure and re-build the bbl in the build directory:
../configure \
 --enable-sm \
 --with-target-platform= \
 --host=riscv64-unknown-linux-gnu \
 --with-payload=
Each platform directory contains a top-level C file that handles the module.
For example, --with-target-platform=fu540 will include sm/platform/fu540/fu540.c in the SM. Each of the directories contains the hooks for each platform.
The platform directory sm/platform contains all current platform specific supports.
Currently that is: default and fu540 directories.
1.7. System PMP Synchronization
System PMP is not supported yet.
1.8. Side-Channel Defense
The FU540 module supports cache side-channel defenses.
1.9. Current Enclave Lifecycle
digraph G {
 node [color=gray]
 Invalid -> Allocated [color=blue,label="allocate_eid\n(create_enclave)"];
 node [color=orange]
 Allocated -> Fresh [color=orange,label="create_enclave\nafter\nvalidate and hash"];
 node [color=red]
 Allocated -> Destroying [color=red,label="destory_enclave\n(first step)"];
 node [color=green]
 Fresh -> Running [color=green,label="run_enclave"];
 Running -> Stopped [color=yellow1,label="exit/stop_enclave"];
 Stopped -> Running [color=green,label="resume_enclave"];
 Destroying -> Invalid [color=gray,label="free_eid\n(destory_enclave\nlast step)"];


Preparatory studies
Study of Female Head to Right by Burne Jones
Study of Female Head to Right, 1889
Burne-Jones produced studies and drawings as research for larger drawings, watercolours and tapestries. Including studies made for major works such as his 'Pygmalion Series', 'The Briar Rose Series' and 'The Wheel of Fortune'. They reveal Burne-Jones' exhaustive method of building compositions and his passion for Romantic and classical literature.


text:
The purpose of this register is the same as the Individuals Register. Registration should be required for all foreign nationals who wish to:
- Enter the country;
- Own domestic currency;
- Own domestic land;
- Own shares in domestic companies;
- Commence or defend domestic legal proceedings;
- Be a director of a domestic corporation.
The Foreign Nationals Register should contain the same fields as the Individuals Register. It should reveal whether a person is currently in or out of the country, how long they are legally entitled to stay, and under what visa conditions they have entered. This information should be publicly accessible and, among other uses, will allow prospective employers to know whether they can employ a person and for how long, and members of the public to report the location of persons overstaying or breaching the conditions of their visa.