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Chapter 4. Scaling storage nodes
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To scale the storage capacity of OpenShift Container Storage, you can do either of the following:
 - Scale up storage nodes - Add storage capacity to the existing Red Hat OpenShift Container Storage worker nodes
 - Scale out storage nodes - Add new worker nodes containing storage capacity
4.1. Requirements for scaling storage nodes
Before you proceed to scale the storage nodes, refer to the following sections to understand the node requirements for your specific Red Hat OpenShift Container Storage instance:
Warning
Always ensure that you have plenty of storage capacity.
If storage ever fills completely, it is not possible to add capacity or delete or migrate content away from the storage to free up space. Completely full storage is very difficult to recover.
Capacity alerts are issued when cluster storage capacity reaches 75% (near-full) and 85% (full) of total capacity. Always address capacity warnings promptly, and review your storage regularly to ensure that you do not run out of storage space.
If you do run out of storage space completely, contact Red Hat Customer Support.
4.1.1. Supported Deployments for Red Hat OpenShift Container Storage
 - User-provisioned infrastructure:
 - Amazon Web Services (AWS)
 - VMware
 - Bare metal
 - Installer-provisioned infrastructure:
 - Amazon Web Services (AWS)
4.2. Scaling up storage capacity
Depending on the type of your deployment, you can choose one of the following procedures to scale up storage capacity.
4.2.1. Scaling up storage by adding capacity to your OpenShift Container Storage nodes on AWS or VMware infrastructure
Use this procedure to add storage capacity and performance to your configured Red Hat OpenShift Container Storage worker nodes.
Prerequisites
 - A running OpenShift Container Storage Platform
 - Administrative privileges on the OpenShift Web Console
Procedure
 1. Navigate to the OpenShift Web Console.
 2. Click on Operators on the left navigation bar.
 3. Select Installed Operators.
 4. In the window, click OpenShift Container Storage Operator:
 ocs installed operators
 5. In the top navigation bar, scroll right and click Storage Cluster tab.
 OCS Storage Cluster overview reachit
 6. The visible list should have only one item. Click (⋮) on the far right to extend the options menu.
 7. Select Add Capacity from the options menu.
 OCS add capacity dialog menu
 From this dialog box, you can set the requested additional capacity and the storage class. Add capacity shows the capacity selected at the time of installation and allows to add the capacity only in this increment. On AWS, the storage class should be set to gp2. On VMWare, the storage class should be set to thin.
 Note
 The effectively provisioned capacity will be three times as much as what you see in the Raw Capacity field because OpenShift Container Storage uses a replica count of 3.
 8. Click Add. You can see the status of the storage cluster after it reaches the Ready state. You might need to wait a couple of minutes after you see the Ready state.
Verification steps
 1. Navigate to Overview Persistent Storage tab, then check the Capacity breakdown card.
 ocs add capacity expansion verification
 2. Note that the capacity increases based on your selections.
Important
OpenShift Container Storage does not support cluster reduction either by reducing OSDs or reducing nodes.
4.2.2. Scaling up storage by adding capacity to your OpenShift Container Storage nodes using local storage devices
Use this procedure to add storage capacity (additional storage devices) to your configured local storage based OpenShift Container Storage worker nodes on bare metal, Amazon EC2 I3, and VMware infrastructures.
Important
Scaling up storage on Amazon EC2 I3 is a Technology Preview feature. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
Note
For Amazon EC2 I3 infrastructure, adding nodes is the only option for adding capacity, as deployment is done using both the available NVMe devices.
Prerequisites
 - You must be logged into OpenShift Container Platform (OCP) cluster.
 - You must have installed local storage operator. For information, see Installing Local Storage Operator.
 - You must have three OpenShift Container Platform worker nodes with the same storage type and size attached to each node (for example, 2TB NVMe drive) as the original OCS StorageCluster was created with.
Procedure
 1. To add storage capacity to OpenShift Container Platform nodes with OpenShift Container Storage installed, you need to
 1. Find the unique by-id identifier for available devices that you want to add, that is, a minimum of one device per worker node. Follow procedure finding available storage devices.
 Note
 Make sure you perform this process for all the existing nodes (minimum of 3) for which you want to add storage.
 2. Add unique device by-id.
 $ oc edit -n local-storage localvolume local-block
 Example output:
 spec:
 logLevel: Normal
 managementState: Managed
 nodeSelector:
 nodeSelectorTerms:
 - matchExpressions:
 - key: _URL_-storage
 operator: In
 values:
 - ""
 storageClassDevices:
 - devicePaths:
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402P51P0GGN
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402LM1P0GGN
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402M21P0GGN
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402B71P0GGN # newly added device by-id
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402A31P0GGN # newly added device by-id
 - /dev/disk/by-id/nvme-INTEL_SSDPE2KX010T7_PHLF733402Q71P0GGN # newly added device by-id
 storageClassName: localblock
 volumeMode: Block
 Make sure to save the changes after editing the CR.
 localvolume.local.storage.openshift.io/local-block edited
 You can see that in this CR new devices using by-id have been added. Each device maps to nvme1n1 on one of the three worker nodes.
 - nvme-INTEL_SSDPE2KX010T7_PHLF733402B71P0GGN
 - nvme-INTEL_SSDPE2KX010T7_PHLF733402A31P0GGN
 - nvme-INTEL_SSDPE2KX010T7_PHLF733402Q71P0GGN
 2. Display PVs with storageclass name used in localVolume CR.
 $ oc get pv | grep localblock | grep Available
 Example output:
 local-pv-5ee61dcc 894Gi RWO Delete Available localblock 2m35s
 local-pv-b1fa607a 894Gi RWO Delete Available localblock 2m27s
 local-pv-e971c51d 894Gi RWO Delete Available localblock 2m22s
 ...
 There are three more available PVs of same size which will be used for new OSDs.
 3. To expand storage capacity, increase the count by 1 for StorageDeviceSets in StorageCluster CR.
 $ oc edit storageclusters.ocs.openshift.io -n openshift-storage
 Example output:
 spec:
 monDataDirHostPath: /var/lib/rook
 storageDeviceSets:
 - config: {}
 count: 2 # <-- increase this count by 1
 dataPVCTemplate:
 metadata:
 creationTimestamp: null
 spec:
 accessModes:
 - ReadWriteOnce
 resources:
 requests:
 storage: 894Gi
 storageClassName: localblock
 volumeMode: Block
 status: {}
 name: ocs-deviceset
 placement: {}
 replica: 3
 resources: {}
 version: 4.4.0
 Make sure to save the changes after editing the CR.
 _URL_-storagecluster edited
 Important
 To ensure that the OSDs have a guaranteed size across the nodes, the storage size for storageDeviceSets must be specified as less than or equal to the size of the desired PVs created on the nodes.
 4. Verify that there are three new OSDs running and their corresponding new PVCs are created.
 $ oc get -n openshift-storage pods -l app=rook-ceph-osd
 Example output:
 NAME READY STATUS RESTARTS AGE
 rook-ceph-osd-0-77c4fdb758-qshw4 1/1 Running 0 1h
 rook-ceph-osd-1-8645c5fbb6-656


text:
Sensei Zen's Pro Tips:
Master a consistent fling:
Try sliding your finger the same distance each time, and adjust the speed accordingly. Sliding your finger too short usually will result in your fling either going faster or slower than you intended.
Master the straight shot:
If you don't like the angle you are sliding your finger, rotate your iPhone to provide an easier sliding path, usually vertical.
Master the world tricks:
Each world will provide a different type of challenge, so be sure to read the tutorial screen at the beginning of each world to find out what to expect from that world.
Master the round name:
Each round name will provide a hint to what the round will be like.
Master a top score:
Gather extra points by causes ricochets and combos to increase your score. However, gaining small bonuses at the cost of a fling is rarely worth it. The best way to gain a high score is to free play each world to master its tricks.
Master the edges:
When you are too close to an edge it may be difficult to put your finger in the right place to get the power of the slide you want. You can easily solve this by placing your finger anywhere on the screen and slide it at the same angle you would if it wasn't on the edge.

source: openbmb/Ultra-FineWeb


plough into
Definition from Wiktionary, the free dictionary
Jump to: navigation, search
See also: plow into
plough into (third-person singular simple present ploughs into, present participle ploughing into, simple past and past participle ploughed into)
 1. To crash into something.
 The lorry ploughed into the line of stationary cars.
 2. To engage in some activity with vigor
 - 2011, The Economist, Samsung: The next big bet
 In a bid to escape the vagaries of consumer electronics, Samsung may be ploughing headlong into the areas most ripe for invasion by a new breed of emerging-market titans.
 3. (transitive) To invest a resource (money, material, energy) into something
 - 2012, The Economist, Marketing start-ups: Geeks aren't known for their social skills
 Young start-ups usually have had two financing options: hands-off venture capitalists that are willing to plough money into a company without rolling up their sleeves, or business incubators that are short on funds but wealthy in enthusiasm and knowledge.


3.7.6 _USER_: Environment Indenting
The Texinfo processors indent each line of _USER_ and similar environments. You can use the _USER_ command to specify this indentation. Write an _USER_ command at the beginning of a line followed by either 'asis' or a number:
_USER_ indent
The indentation is according to the value of indent:
Do not change the existing indentation (not implemented in TeX).
Omit all indentation.
Indent environments by n space characters in Info output, by n ems in TeX.
The default value of indent is 5 spaces in Info, and 0.4in in TeX, which is somewhat less. (The reduction is to help TeX fit more characters onto physical lines.)
It is best to write the _USER_ command before the end-of-header line at the beginning of a Texinfo file, so the region formatting commands indent paragraphs as specified. See Start of Header.


text:
Bad Breath Chemical Could Fuel Growth Of Liver Stem Cells
The gas compound that causes bad breath and flatulence (hydrogen sulphide (H2S)), could fuel the growth of liver stem cells, Japanese scientists have discovered.
Researchers from the Nippon Dental University in Japan discovered that the gas, notorious for its egg-like stench, can help teeth stem cells transform into liver stem cells.
They hope their findings could lead to damaged liver cells being repaired using regenerated ones derived from tooth pulp.
Experts used the H2S gas to enhance the growth of stem cells from one part of the body to another - in this case, dental pulp (the middle part of the tooth made of tissue and cells) was converted into liver stem cells.
The teeth cells were taken from a group of dental patients undergoing routine tooth extractions and were then separated into two groups. One group of cells was incubated in a H2S chamber and the other acted as a control.
The stem cells were analysed after three, six and nice days to track their transformation into liver cells. They also tested their ability to function like liver cells.
Researchers say they experienced an increased population of liver stem cells, although the study did not reveal how many were made. The experts claim the H2S gas boosted the purity of the stem cells, causing them to convert at a rapid speed.
"High purity means there are less 'wrong cells' that are being differentiated to other tissues, or remaining as stem cells," says lead author Dr Ken Yaegaki, reports the Press Association.
"Moreover, these facts suggest that patients undergoing transplantation with the hepatic (liver) cells may have almost no possibility of developing teratomas (tumours) or cancers.
"Until now, nobody has produced the protocol to regenerate such a huge number of hepatic cells for human transplantation.
"Compared to the traditional method of using foetal bovine serum to produce the cells, our method is productive and, most importantly, safe."
Researchers are hoping their findings could help repair damaged liver cells using regenerated ones derived from tooth pulp, however there were questions on the number of dental stem cells that could be harvested.
The findings were published in the Journal of Breath Research.
This is not the first time hydrogen sulphide gas has been cited as having health benefits. In 2008, scientists from the John Hopkins University found that small amounts of the chemical relaxes blood vessels, lowering blood pressure.
Skin Cancer Drug Doubles Survival Rate
A twice-daily skin cancer drug almost doubles the survival times of advanced cancer patients, American scientists have discovered. Researchers from the Jonsson Cancer Center at the University of California, found that advanced melanoma cancer sufferers lived on average of 16 months after receiving the vemurafenib drug. Read the full story here. Read the full story here
Breakthrough Test Could Predict Heart Attacks And Strokes
Scientists have discovered five new genes that cause heart attacks and strokes and hope these findings will enable them to pinpoint when the attacks will strike. The researchers, from Queen Mary University of London, identified five generic variants that trigger heart attacks and strokes after investigating blood pressure measurements of 25,000 participants. The aim of the study was to look into the role that genes play in hypertension and high blood pressure. Read the full story here.
Skin Cancer Pill Brings Fresh Hope To Alzheimer's Sufferers
American scientists have discovered a potential new drug that could help fight against Alzheimer's disease. Neuroscientists from the Case Western Reserve University School of Medicine discovered that a skin cancer drug called bexarotene appears to reverse cognitive and memory deficits associated with Alzheimer's when tested on lab mice. Read the full story here.
Personalised Skin Cancer Drugs Brings Fresh Hope
A "personalised" pill for advanced skin cancer that can extend life has been approved for use in the UK. The drug, vemurafenib, only works for patients with a specific variant of the BRAF gene. Read the full story here.
Genetic Breakthrough Raises Hope For Breast Cancer Sufferers
The genetic code of the most common form of hereditary breast cancer has been mapped for the first time, offering hope for diagnosis and treatment of the disease in the future. Researchers say they have "fully sequenced" the DNA of two breast cancers caused by a faulty BRCA1 gene, which is responsible for aggressive and highly drug-resistant tumours. Read the full story here.
Peanut Allergies - Have Scientists Finally Found A Cure?
Scientists from the Northwestern University in Chicago have come one step closer to developing a potential cure for peanut allergies, by creating an immune system tolerant to peanuts. The researchers found that they can switch off potentially deadly peanut allergy attacks by tricking the immune system into tolerating nut proteins, and not seeing them as a threat to the body. Read the full story here.
Lung Cancer Detection Test Trial
A breakthrough lung cancer detection test is set to be trialled on smokers for the first time in Scotland. If successful, cancers could be identified five years earlier than by current detection methods. Read the full story here.
Cure For Insomnia A Step Closer After Scientists Discover The Enzyme That Wakes Us Up
Sleepless nights could soon be a thing of the past as scientists discover a key chemical trigger that suppresses sleep and wakes people up. Researchers from Boston University found that when the body has too little of the calcium kinase enzyme, it causes the brain to nod off to sleep. Read the full story here.
Boiling Breast Cancer Tumours Kills Them In Minutes, Discover Experts
A new treatment for breast cancer has been discovered after scientists found that breast tumours can be killed in minutes - by boiling them. The latest treatment, known as Preferential Radio-Frequency Ablation, uses a targeted electrical current that heats, or 'boils' the tumour to 70 to 90c (160 to 190f). Read the full story here.
New Scan Detects Breast Cancer In Seconds Using Anti-Landmine Technology
British scientists have developed a revolutionary breast-screening system that uses anti-landmine technology to detect cancer in seconds. The radio-wave scanner is safer, cheaper and less painful than traditional mammogram X-rays, and unlike the current system, can be used on women of all ages. Read the full story here.
Stem Cell Transplant Offers New Hope For Autism and Parkinson's
Breakthrough research involving a brain transplant of stem cells could offer hope for the treatment of both autism and Parkinson's disease. The study, from Harvard University, has already proven successful with mice. Scientists transferred healthy stem cells from mouse embryos into the brains of adult mice who were unable to use leptin, a hormone that tells the body when to stop eating.

source: HuggingFaceFW/fineweb-edu


text:
In short: Why is Norway a Space Nation?
Norway is a small, but active space nation, and was one of the first countries to launch rockets.
There are many reasons Norway looked to space. Here is the short version:
Norway was and is a shipping nation. Thus, Norway had a need for satellite communication with ships all over the world and with off-shore installations in the North Sea.
Norway joined the International Maritime Satellite Organization (Inmarsat), founded in 1976, early. Norway was also one of the largest owners of Inmarsat, before the organization was commercialized. Telenor was an early adopter of satellite communication and bought its first satellite in 1992.
A sub-orbital rocket launch from Andøya Space in Northern Norway.
In the 1970s, the world's oceans were divided into economic zones. With that, Norway's area increased greatly, and the country needed to monitor large sea areas for maritime activity. Norway wanted to use radar satellites for this purpose, and made a cooperation agreement with Canada for data from Radarsat-1. This satellite was launched in 1995.
In 1987, Norway joined the European Space Agency, ESA, and gained access to the data from ESA's radar satellite ERS-1, which was launched in 1991. Since then, Norway has participated in most of ESA's programs. Norway is also actively participating in the EU's space programs.
As an oil producing nation, drilling from deep offshore sites, Norway has gathered a work force with competence in highly advanced technology. This is certainly an advantage for the national space sector.
The first sounding rocket for scientific research was launched from Andøya as early as 1962. The Norwegian scientists wanted to know more about the ionosphere and how it affects radio communication. Later, the launches from Andøya were done for basic research on the northern lights and the atmosphere.
Today, Andøya Space is building Andøya Spaceport, a launch base for small satellites for commercial and governmental use.

source: m-a-p/FineFineWeb


Readers ask: Learning How To Publish An Online Magazine?
How do I publish an online magazine?
How To Publish Your Magazine Online
 1. Turn it into a website.
 2. Publish it as a downloadable PDF.
 3. Embed it using SlideShare.
 4. Use a third-party magazine hosting app.
 5. Conclusion.
Do online magazines make money?
Online publications generate revenue through banner ads, click-per-pay programs, links, affiliate programs, mailing lists and editorial opportunities. The publisher can sell its own banner ads directly to advertisers or use a program such as Google's AdSense, allowing the program to place ads on e-zine pages.
How can I publish a magazine online for free?
 1. 3 tools to publish a free magazine online. Home | Blog | Digital Publication | 3 tools to publish a free magazine online.
 2. ISSUU. ISSUU is quite versatile as they're not only focused on publishing digital magazines.
 3. PaperLit.
 4. Joomag.
How much does it cost to start an online magazine?
You might be interested: FAQ: What Is The Same In Online And Face To Face Learning?
How do you start an online magazine and make money?
In this post we'll cover 5 ways you can turn a profit with your online magazine.
 1. Use display advertising. As with traditional magazines, ads play a big role in funding e-magazines.
 2. Try native advertising.
 3. Make an app.
 4. Become a subscription service.
 5. Ask for donations.
How do I start an online magazine business?
How to Start an Online Magazine
 1. Pick a topic for your magazine.
 2. Do research to find out if there's a market for your idea.
 3. Think of a title for your magazine that includes search-engine optimized keywords.
 4. Get an Internet domain name.
 5. Decide if you're going to hire someone to design your website or if you're going to do it yourself.
Are magazines still profitable?
How do magazines make most of their money answers?
How do I publish an issue?
Publishing to Issuu for Digital Distribution
 1. Click on Publish in the top navigation menu.
 2. Add the title of your publication, a short description and the original publishing date of the document.
 3. Under Access, you can choose to make your document public or keep it unlisted.
 4. Choose whether to make your publication available for downloading.
Is issuu legal?
You do not need to worry about whether is Issuu legal. (If you would not have already guessed it: Issuu is legal – so continue reading to find out how Issuu works). Issuu, a Joomag alternative, will simply take those PDF files and convert them into flash readable content publications.
You might be interested: Question: How Is Online Learning Different From Bricks And Mofar Learning?
How do I start a small local magazine?
While starting a magazine might seem like too daunting an enterprise to attempt, it can be done with some careful planning and dedication.
 1. Do market research.
 2. Create a business plan that explains the ins and outs of your magazine.
 3. Get the content.
 4. Create the magazine on your computer.
 5. Lay out the content.
What is the number 1 magazine in the world?
What are the 3 types of magazines?
This guide offers an introduction to the three main types of periodicals –scholarly, trade, and popular–and ways to distinguish among them.
What is an online magazine called?
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text:
CHC Home | History & Links | Finding Aids (return to cambridgearchives.org)
Cambridge Social Union / Cambridge Center for Adult Education Collection Finding Aid (pdf version available)
Cambridge Historical Commission
831 Massachusetts Ave.
Cambridge, MA 02139
Tel. _PHONE_
Fax. _PHONE_
Prepared by: Molly Alexander, Maeve Strucker (?)
Acquisition Date: May 1998
William W. Vaughan and a group of like-minded citizens founded the Cambridge Social Union (CSU) in 1871. In the beginning it had a piano for musical entertainment, a lending library and reading room. Soon literacy and other classes were started, mostly taught by Harvard College students, as well as a Boys Club started by Anne W. Abbot. The CSU was incorporated in 1876, and that same year moved to 15 Brattle St. In 1889 the CSU again moved, to the William Brattle House at 42 Brattle St. During World War I the CSU suffered a decline in gifts and contributions as well as in services offered. In 1937 a feasibility study was conducted, and as a result in 1938 the CSU and the Boston Center for Adult Education started the Cambridge Center for Adult Education (CCAE), which offered evening courses. In 1941 the CCAE became an independently administered institution and Lydia Weare was made the Director. The CCAE almost closed in 1942 due to a lack of enrollment, but persevered another year and was quite successful throughout World War II. In 1948 Brattle Hall was sold in order to concentrate on developing the CCAE's educational facilities, and in 1972 the CCAE bought the Blacksmith House at 56 Brattle St. and the Dexter Pratt House at 1 Story St. from the Window Shop. As part of the sale, the CCAE agreed to keep the Window Shop bakery and its employees until they all retired. The CCAE is a non-profit organization that offers classes for adults ranging from cooking to foreign languages to computer programming and software.
Scope and Content
The collection includes the annual reports of the CSU from _PHONE_, CSU by-laws, records of meetings and members 1870s-1890s, business correspondence, program information, financial records, records of library accessions, two scrapbooks that contain mostly newspaper clippings, a sonnet by John Lothrop Motley, and a framed reproduction of a portrait of General William Brattle. This collection documents the early history and changes over time of an important and long standing Cambridge institution.
Box 1 of 6 / annual reports
- This box contains multiple copies of annual reports from 1875 through 1916. It also contains responses to an invitation to meet the subscribers to the building fund at Brattle Hall (42 Brattle St.) and two copies of the invitation.
Box 2 of 6 / annual reports (contd)
- This box contains multiple copies of annual reports from 1875 through 1916.
Box 3 of 6 / records of meetings
and members, 1870s-1890s
- Cambridge Social Union by-laws
- Records of meetings _PHONE_
- Records of members 1870s-1891 (bound volume)
- Records [of meetings?] _PHONE_ (bound volume)
Box 4 of 6 / correspondence and program info.
- (untitled) contains Brattle House info., newspaper clippings, and duplicate copy of john Lothrop Motley sonnet.
- Sonnet by John Lothrop Motley, 1831
- (untitled) contains notebook titled Pottery II, Jaqui Thornell
- CSU: correspondence, 1940s
- CSU, corporate correspondence, 1920s
- CSU- corporate correspondence, 1930s
- CCAE News Release "Cambridge Center for Adult Education Celebrates Centennial of service to Adult Education" 1971
- Cambridge Social Union Report of a Study of the CSU, December 1937
- Miscellaneous correspondence, _PHONE_
- Better Brattle House Fund, post-fire insurance info., etc. 1955
- Cambridge Social Union: miscellaneous correspondence
- Miscellaneous program information
Box 5 of 6 / ledgers
- Records of library accessions, dates unknown (bound volume)
- Expenditures, _PHONE_ (bound volume)
- Charles River Trust Co., three deposit slip books, one book for interest paid on deposits
Box 6 of 6 / scrapbooks
- Two bound scrapbooks with mainly newspaper clippings
Unboxed single item:
- "Reproduction of General William Brattle portrait (framed)."
James Smith, Executive Director of the Cambridge Adult Education Center, loaned part of the collection to the Cambridge Historical Commission in May 1998 and additional material in January 1999.
Cambridge Historical Commission.
"Cambridge Center for Adult Education" folder, filed under "Clubs,
Cambridge Historical Commission. "Cambridge Social Union" folder, filed under "Clubs, Churches, Associations."
Return to CHC Finding Aids home
(return to cambridgearchives.org)


next up previous
Next: Ray Tracing Up: Waves in Cold Plasmas Previous: Collisional Damping
Pulse Propagation
Consider the situation under investigation in Sect. 4.12, in which a plane wave, polarized in the $y$-direction, is launched along the $z$-axis, from an antenna located at large positive $z$, and reflected from a cutoff located at $z=0$. Up to now, we have only considered infinite wave-trains, characterized by a discrete frequency, $\omega$. Let us now consider the more realistic case in which the antenna emits a finite pulse of radio waves.
The pulse structure is conveniently represented as
\begin{displaymath}
E_y(t) = \int_{-\infty}^{\infty} F(\omega)\,{\rm e}^{-{\rm i} \, \omega \,t}\,d\omega,
\end{displaymath} (622)
where $E_y(t)$ is the electric field produced by the antenna, which is assumed to lie at $z=a$. Suppose that the pulse is a signal of roughly constant (angular) frequency $\omega_0$, which lasts a time $T$, where $T$ is long compared to $1/\omega_0$. It follows that $F(\omega)$ possesses narrow maxima around $\omega=\pm
\omega_0$. In other words, only those frequencies which lie very close to the central frequency $\omega_0$ play a significant role in the propagation of the pulse.
Each component frequency of the pulse yields a wave which propagates independently along the $z$-axis, in a manner specified by the appropriate WKB solution [see Eqs. (569)-(570)]. Thus, if Eq. (622) specifies the signal at the antenna (i.e., at $z=a$), then the signal at coordinate $z$ (where $z<a$) is given by
\begin{displaymath}
E_y(z,t) = \int_{-\infty}^{\infty} \frac{F(\omega)}{n^{1/2}(\omega, z)}\,\,
{\rm e}^{\,{\rm i}\, \phi(\omega, z,t)}\,d\omega,
\end{displaymath} (623)
where
\begin{displaymath}
\phi(\omega, z,t) = \frac{\omega}{c} \int_z^{a} \!n(\omega, z)\,dz - \omega \,t.
\end{displaymath} (624)
Here, we have used $k_0=\omega/c$.
Equation (623) can be regarded as a contour integral in $\omega$-space. The quantity $F/n^{1/2}$ is a relatively slowly varying function of $\omega$, whereas the phase, $\phi$, is a large and rapidly varying function of $\omega$. The rapid oscillations of $\exp(\,{\rm i}\,\phi)$ over most of the path of integration ensure that the integrand averages almost to zero. However, this cancellation argument does not apply to places on the integration path where the phase is stationary: i.e., places where $\phi(\omega)$ has an extremum. The integral can, therefore, be estimated by finding those points where $\phi(\omega)$ has a vanishing derivative, evaluating (approximately) the integral in the neighbourhood of each of these points, and summing the contributions. This procedure is called the method of stationary phase.
Suppose that $\phi(\omega)$ has a vanishing first derivative at $\omega=\omega_s$. In the neighbourhood of this point, $\phi(\omega)$ can be expanded as a Taylor series,
\begin{displaymath}
\phi(\omega) = \phi_s + \frac{1}{2} \phi''_s(\omega-\omega_s)^2+\cdots.
\end{displaymath} (625)
Here, the subscript $s$ is used to indicate $\phi$ or its second derivative evaluated at $\omega=\omega_s$. Since $F(\omega)/n^{1/2}(\omega,z)$ is slowly varying, the contribution to the integral from this stationary phase point is approximately
\begin{displaymath}
E_{y\,s} \simeq \frac{F(\omega_s) \,{\rm e}^{\,{\rm i}\,\phi...
...} {\rm e}^{\,({\rm i}/2)\phi_s''(\omega-\omega_s)^2}\,d\omega.
\end{displaymath} (626)
The above expression can be written in the form
\begin{displaymath}
E_{y\,s}\simeq \frac{F(\omega_s) \,{\rm e}^{\,{\rm i}\,\phi_...
...left[
\cos(\pi \,t^2/2)+{\rm i}\,\sin(\pi\, t^2/2)\right]\,dt,
\end{displaymath} (627)
where
\begin{displaymath}
\frac{\pi}{2}\, t^2 = \frac{1}{2}\, \phi_s'' \,(\omega-\omega_s)^2.
\end{displaymath} (628)
The integrals in the above expression are Fresnel integrals,[*] and can be shown to take the values
\begin{displaymath}
\int_0^\infty\cos(\pi \,t^2/2)\,dt = \int_0^\infty\sin(\pi\, t^2/2)\,dt
=\frac{1}{2}.
\end{displaymath} (629)
It follows that
\begin{displaymath}
E_{y\,s}\simeq \sqrt{\frac{2\pi\,{\rm i}}{\phi_s''}}
\, \fra...
...omega_s)}{n^{1/2}(\omega_s, z)} \,{\rm e}^{\,{\rm i}\,\phi_s}.
\end{displaymath} (630)
If there is more than one point of stationary phase in the range of integration then the integral is approximated as a sum of terms like the above.
Integrals of the form (623) can be calculated exactly using the method of steepest decent.[*] The stationary phase approximation (630) agrees with the leading term of the method of steepest decent (which is far more difficult to implement than the method of stationary phase) provided that $\phi(\omega)$ is real (i.e., provided that the stationary point lies on the real axis). If $\phi$ is complex, however, the stationary phase method can yield erroneous results.
It follows, from the above discussion, that the right-hand side of Eq. (623) averages to a very small value, expect for those special values of $z$ and $t$ at which one of the points of stationary phase in $\omega$-space coincides with one of the peaks of $F(\omega)$. The locus of these special values of $z$ and $t$ can obviously be regarded as the equation of motion of the pulse as it propagates along the $z$-axis. Thus, the equation of motion is specified by
\begin{displaymath}
\left(\frac{\partial\phi}{\partial\omega}\right)_{\omega=\omega_0} = 0,
\end{displaymath} (631)
which yields
\begin{displaymath}
t = \frac{1}{c} \int_z^a \left[\frac{\partial(\omega \,n)}{\partial\omega}
\right]_{\omega=\omega_0}\, dz.
\end{displaymath} (632)
Suppose that the $z$-velocity of a pulse of central frequency $\omega_0$ at coordinate $z$ is given by $-u_z(\omega_0,z)$. The differential equation of motion of the pulse is then $dt = -dz/u_z$.


text:
Scotland Land and PropertyEdit This Page
From FamilySearch Wiki
Land records can help you determine where and when your family lived in a specific place. Sometimes these records will be based on inheritance, and such records will often mention two or more generations of a family. In Scotland the land system had feudal roots in which the crown owned all of the land.
Many courts were involved in actions regarding land. Some of the most important courts were:
- Chancery Courts
- Court of Session
- Sheriff Courts
- Burgh Courts
- Commissary Courts
- Regality Courts
In general, there are three types of Scottish land records:
Most of our Scottish ancestors never owned land but rather lived and farmed land belonging to someone else. The Estate owner kept management records of their lands, estates and tenants. Some of these records have survived and reside either in the hands of the current estate owner or are at the National Archives of Scotland (NAS) as a Gift and Depost (GD). Some large estates have their own archives on-sight. The types of papers in an estate could be:
- Rentals or leases called a 'tack'
- Lists of tenants
- Records of tenants who may have been in some trouble
In order to search estate records you need to know who owned the estate. To find this information search these sources available either online or at the FHL:
- Parish histories and gazetteers
- The Old & New Statistical Accounts of Scotland at the FHL and online at Edina.ac.uk
- Findlay, James. Directory of Gentlemen's' Seats, villages, &c. in Scotland… (FHL book Ref 941 E4d; film 599347 item 3; fiche _PHONE_) online at Archives.org
- Register of the Great Seal _PHONE_, 11 vols. (FHL book 941 N2sc): _PHONE_ are available on Ancestry
- Statistics of the annexed estates, _PHONE_: from the records of the forfeited estates preserved in the Scottish Record Office [NAS]. FHL Q book 941 R2sa. Lists tenants on the estates forfeited as a result of the 1745 Rebellion.
- Index of Place Names to the Abridgements of Sasines (see that section)
- Timperley, Loretta R. Directory of Landownership in Scotland circa 1770. (FHL book 941 B4sr n.s. v. 5)
- Return of Owners of Land and Heritages in Scotland 1872-73 (FHL Q book 941 R25i)
- National Register of Archives (searchable online) _URL_
Once the name of the land owner has been determined, search the NAS' catalog for their name or the property name along with references of E,GD or RH. The FHL catalog should also be searched under the county where the property was located and look under the topic of "Land and Property".
Taxes were determined by the value of the land. These records are called 'valuation rolls' and exist sporadically before 1855. The book entitled "Directory of Landownership in Scotland circa 1770" is based in part on the valuation rolls for that year. The FHL has only a few of these records and most are listed in the NAS online catalog with the reference of VR. To learn more about these records go to _URL_
For More Information
For more information about sasine, service of heir, deeds, and other Scottish land and property records, see the following website and books:
National Archives of Scotland Look at the "Guides to Records".
Dobson, David. Scottish-American Heirs _PHONE_. Baltimore, Maryland: Genealogical Publishing Co., Inc., 1990. (Family History Librarybook 941 D2d.)
Encyclopedia of the Laws of Scotland. 16 vols and 2 supps. Edinburgh, Scotland: W. Green & Son, Limited, 1926. (Family History Library book 941 P36e.)
Gibb, Andrew Dewar. Students' Glossary of Scottish Legal Terms. Edinburgh, Scotland: W. Green & Son, Ltd., 1946. (Family History Library book 941 P36g.)
Gouldesbrough, Peter. Formulary of Old Scots Legal Documents. Vol. 36. Edinburgh, Scotland: The Stair Society, 1985. (Family History Library book 941 B4st v.36.)
An Introductory Survey of the Sources and Literature of Scots Law. Vol. 1. The Stair Society. Edinburgh, Scotland: Robert Maclehose & Co., Ltd. for The Stair Society, 1936. (Family History Librarybook 941 B4st; film _PHONE_.)
Sinclair, Cecil. Tracing Your Scottish Ancestors: A Guide to Ancestry Research in the Scottish Record Office. Edinburgh, Scotland: Her Majesty's Stationery Office, 1990. (Family History Library book 941 D27s.)


Access AddToFavorites Method Example
AddToFavorites Method – the Add To Favorites method adds the name of the current database to the Favorites folder. When applied to a Control object, the AddToFavorites method adds the hyperlink address contained in a control to the Favorites folder.
The Add To Favorites method has the same effect as clicking AddToFavorites on the Favorites menu on the Web toolbar when view a page on the internet.
Here is an example of adding to favorites the hyperlink contained in a control field on a form:
We add our Blue Claw Database Design url to the field called Field1 on the form. This happens when the form loads in the Form Load event. You could also allow the user to type in the hyperlink address or select it from a list.
Private Sub Form_Load()
Me!Field1.HyperlinkAddress = "_URL_
End Sub
Next, we add the link to our favorites list when the user clicks the Field1 hyperlink.
Private Sub Field1_Click()
Me!Field1.Hyperlink.AddToFavorites
End Sub
Access Database Tutorials:
Access ErrorAddToFavoritesCloseCurrentDatabase
CodeDBCompactRepair CompactRepairConvertAccessProject


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Free Vibration of SDOF systems Realised by Zied souissi.
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... konulu sunumlar: "Free Vibration of SDOF systems Realised by Zied souissi."— Sunum transkripti:
1 Free Vibration of SDOF systems Realised by Zied souissi
2 Definition The minimum number of independent coordinates required to determine completely the positions of all parts of a system at any instant of time defines the degree of freedom of the system. A single degree of freedom system requires only one coordinate to describe its position at any instantof time.
3 Single degree of freedom system For the simple pendulum in the figure, the motion can be stated either in terms of θ or x and y. If the coordinates x and y are used to describe the motion, it must be recognized that these coordinates are not independent. They are related to each other through the relation. where l is the constant length of the pendulum. Thus any one coordinate can describe the motion of the pendulum. In this example, we find that the choice of θ as the independent coordinate will be more convenient than the choice of x and y.
4 Free vibration of undamped SDOF Consider the single ‐ degree ‐ of ‐ freedom (SDOF) system shown in the figure. The spring is originally in the unstretched position as shown. It is assumed that the spring obeys Hooke's law. The force in the spring is proportional to displacement with the proportionality constant (spring constant) equal to k.
5 Free vibration of undamped SDOF The stiffness in a spring can be related more directly to material and geometric properties of the spring. A spring like behaviour results from a variety of configurations, including longitudinal motion (vibration in the direction of the length), transverse motion (vibration perpendicular to the length), and torsional motion(vibration rotating around the length).
6 Free vibration of undamped SDOF
7 Free vibration of undamped SDOF To determine the position as a function of time, the equations of motion are employed; the free body diagrams are drawn as shown in the figure.Note that x is measured positive downward, Applying Newton's second law, But condition from the static condition, note that W=kδst. Thus, the motion becomes: With the standard form of: This is III Case that has complex roots where the general solution was computed as: Since in the above equation: It is shown that
8 Free vibration of undamped SDOF where A et B are constants of integration and Here ωn defines the natural frequency of the mass. This is the frequency at which the mass will move regardless of the amplitude of the motion as long as the spring in the system continues to obey Hooke's law. The natural frequency in Hertz is: The initial conditions x = xo at t=0 and x = x at t = 0 are used to evaluate the constants of integration A and B. When substituted into the equation We get and consequently
9 Free vibration of undamped SDOF The sum in the equation can also be combined to a phase shifted cosine with amplitude and phase angle φ=arctan(B/A). For this purpose let: Introducing the new values of A and B into We get Since X(t) can be expressed as: Where φ=arctan(B/A) and consequently:
10 Free vibration of undamped SDOF The equation is a harmonic function of time Thus, the spring-mass system is called a harmonic oscillator. The nature of harmonic oscillation is shown in the figure. If C denotes a vector of magnitude C, which makes an angle ωnt ‐ φ with respect to the vertical x axis, then the solution x(t)=Ccos(ωt - φ) can be seen to be projection of vector C on the x axis.
11 Damping Undamped and damped vibration: The response of a spring ‐ mass model predicts that the system will oscillate indefinitely. However, everyday observation indicates that most freely oscillating systems eventually die out and reduce to zero motion. The choice of representative model for the observed decay in an oscillating system is based partially on physical observation and partially on mathematical convenience. The theory of differential equations suggests that adding a term to equation of the form, where c is a constant, will result in a solution x(t) that dies out. Physical observation agrees fair well with this model and it is used very successfully to model the damping or decay in a variety of mechanical systems. This type of damping is called the viscous damping.
12 Damping The laminar flow of the oil through the perforations as the piston moves causes a damping force on the piston. The force is proportional to the velocity of the piston, in a direction opposite that of the piston motion. This damping force has the form: where c is a constant of proportionality related to the oil viscosity. The constant c, called the damping coefficient, has units of Ns/m, or kg/s.
13 Damped free vibration of SDOF Consider the spring ‐ mass system with an energy dissipating mechanism described by the damping force as shown in the figure. It is assumed that the damping force FD is proportional to the velocity of the mass, as shown; the damping coefficient is c. When Newton's second law is applied, this model for the damping force leads to a linear differential equation,
14 Damped free vibration of SDOF The ODE is homogeneous linear and has constant coefficients. The characteristic equation is found by dividing the below equation by m: By the roots of a quadratic equation, we obtain: Where It is now most interesting that depending on the amount of damping (much, medium or little) there will be three types of motion corresponding to the three cases I, II and III.
15 Damped free vibration of SDOF
16 Define the critical damping coefficient cc as that value of c that makes the radical equal to zero, Define the damping factor as: Introducing the above equation into We find Then the solution can be written as:
17 Three cases of damping Heavy damping when c > cc Critical damping c = cc Light damping 0 < c < cc
18 To Summarize Natural frequency Damping Ratio Equation of motion Standart form of equation of motion Assume following initial conditions Assume a harmonic solution
19 To Summarize Equation of motionHarmonic solution Types of Free Vibrations
20 To Summarize General harmonic solution Applying initial conditions
21 Example:
22
23 1.Underdamped vibration By applying initial conditions and expand with cos and sine terms gives
24 1.Underdamped vibration
25
26 Example: Governing equation of motion of an underdamped single degree of freedom system is given as a)Find the natural frequency b)Find the damping ratio c)Find the damped natural frequency of the system d)Find the free vibration response amplitude and its phase for the following initial conditions: e) Draw roughly the amplitude-time graphics of the response
27 Example: Governing equation of motion of an underdamped single degree of freedom system shown below is given as a)Find all vibration parameters
28 Solution:
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text:
Irish Fiddle Lessons - Ian Walsh teaches the Irish Hornpipe The Golden Eagle.
Tags:How to Play the Song "The Golden Eagle" on an Iris,Ian Walsh,irish Fiddle Lesson,Learn To Play Fiddle,Learning Irish Fiddle,The Golden Eagle,Violin fiddle lessons
Grab video code:
Hi! Welcome to OnLineLessonVideos.com. I'm Ian Walsh and I'm going to teach an Irish tune today on the fiddle. It's called the Golden Eagle and it's a horn pipe. We'll play it in the key of G.
I'll start off by playing you a sample of the tune along to a quick track that I've set at about 70 beats per minute. So here we go with the Golden Eagle.
Let's begin by leading into this tune with some pickup notes. We'll start on the C, this is on the A string here. You work up A, B, C which plays right next to your first finger pretty much right on top of it. So that could be our first note and we'll start with the triplet here. So three notes and then we'll go to the G. So let's just cycle through that a few times [Demonstration]. Try sliding into your first note, the C and I'll give it a little bit of an aggressive edge [Demonstration].
Let's take a look at another section here, we go down to our B on the g string and we play. So we're crossing three strings, pretty quickly there and I'm not doing anything special with my bow. I'm keeping my bow movement short and I'm working at the top of my bow but I'm not slurring any notes, I'm going straight up and down here. So from B [Demonstration], so those notes are B, D, G, B.
Let's take a look at another section here. We start with the open D. This is a little bit easier, you're only working across two strings and you're using your first and third fingers.
Let's take a look at another one. This is more or less a G arpeggio and it starts on the G on the d string and we play [Demonstration]. So again, you're moving across three strings here ending on the e string on that G note with your second finger.
So let's go back to the beginning here and we'll look at that pickup note, the C, B, A down to your first note of the tune, the G. Take a look at the second little section. You go down to that low B and all the way up to the B again. Then we look here to the low D [Demonstration] and then finally we have that G arpeggio [Demonstration].
Notice I'm leaving my fingers down on the A string here. You can visualize two of the double stamps that are readily apparent here for the G. You can use a G with a D with your A and your E string or you can do the G and the B. Leaving your fingers down can be good practice for getting your fingers just on the individual strings.
Let's put all of these together and see what it sounds like. I'll count us in, one, two, three, [Demonstration] one, two, three [Demonstration]. One more time, one, two, three [Demonstration]


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Unique Pendulum Wave and Release Mechanism
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About: Must... Drink.... Coffee!!!
Intro: Unique Pendulum Wave and Release Mechanism
This is the first half of a two-part instructable. This first half deals primarily with the math (algebra, trigonometry, geometry) involved in creating a pendulum wave and the release, deriving the pendulum wave design and dimensions. Part 2 will detail the process of constucting the pendulum wave. Although the math in this section is fairly easy, it can be very tedious at times. If you have a hard time following the math or even choose to skip the math altogether, you can still build the pendulum wave shown. I have all the necessary models and dimensioned drawings posted in steps 8 and 9, so no worries. :)
Below are a few pictures of the pendulum wave and release mechanism.
Pendulum wave at rest:
Release mechanism beginning to collect pendulums:
Just before releasing the wave:
About 30-35 seconds after release:
About Pendulum Waves
Pendulum waves are simply a series of pendulums that are pulled back, then released at some angle(s). If the lengths and angles are just right, then each pendulum will cycle back and forth between its release position at a slightly different frequency than its neighbor. This results in some pretty neat alternating waveforms. Wave pendulums make great desktop toys for your rich dads, and have even been known to keep children quiet for up to 60 seconds. In addition, the can make nice props in classroom settings for illustrating physics principles such as potential and kinetic energy, air resistance, aliasing, and more.
About the Uniqueness of My Pendulum Wave
To my knowlege, the design for the pendulum wave in this instructable is unique for a number of reasons. First, the wave is intended to be viewed primarily from the top rather than a side (although it looks cool from the side, too). Consequently, it is important that the amplitude of each pendulum appears the same from above. While this requires a more complex release mechanism (instead of the typical flat board), it also leads to a very cool look. As far as I am concerned, a little extra coolness is worth a little extra effort, any day.
Release Mechanism
In order to release the pendulums at the varying release angles required for a top view, I designed a very original release mechanism. Each arm of the mechanism grabs its respective pendulum at a different time. This creates a wave effect as the mechanism curves up and around the pendulums. Once all pendulums have been selected and brought to their proper positions, the mechanism releases them all at the same time, creating the pendulum wave. The math for this is a little tedious, but the concept is pretty straightforward.
Here is a very crappy SolidWorks video demonstrating two arms of the release module in action:
Final Design
Here is an animation of the final design in action. Air resistance was neglected in this animation, which is why no damping occurs. However, since air resistance will not affect the period of the pendulum wave, that is fine.
Step 1: Where the Waves Come From
As I touched on already, a wave pendulum is a series of pendulums with incremented frequencies. One way to think of the pendulum wave is as a series of points used to sample a wave of increasing frequency. This effect is shown in the video below, which I created using Matlab:

The Nyquist Sampling Theory (NST) states that to sample a wave of a given frequency, one needs to measure points at one-half cycle of that frequency. Or, for a given frequency f, one needs points spaced 1/(2*f) units of time apart (since T = 1/f). When the number of sampling points becomes less than the number required by the NST, aliasing occurs. This aliasing is the reason for the alternating waveforms present in a pendulum wave.
Step 2: Choosing the Wave
In order to get a nice, smooth pendulum wave, the frequency of each consecutive pendulum should evenly increase. For my wave, I chose 18 pendulums. I chose value this because during a pendulum wave sequence, about one-third and two-thirds of the way through a complete cycle, the pendulums split into three groups. Halfway through the cycle, the pendulums split into two groups. Thus, to have an even number of pendulums in each group, I chose a value that was a multiple of both 2 and 3. 12 pendulums wasn't enough for me, so I chose 18. I set the frequency of my first to 57 cycles per minute, and made each consecutive pendulum's frequency increase by 1 cpm up to 74 cycles per minute. These values are arbitrary (choose whatever looks best to you). Just make sure that frequencies are incremented by a constant value.
In order to make sure that everything looked right, I made a function in Matlab to animate a plot of a pendulum wave. Below are the function (PWT.m) and a video of what the wave should look like from the top view.

In addition to animating a plot of the wave, this finction also records a video. Due to everyone's systems running at different speeds, the "pause()" function in the script will almost inevitably need to be adjusted to give an accurate representation of the animated wave by accounting for computer delay. The video recorder function, however, will record at the actual speed, so I suggest using it to fine tune your pendulum wave rather than the animation.
To generate the movie shown above, after the function is copied into your matlab directory, type:
>> PWT(18,57/60,1/60,60)
To better understand the function, type
>> help PWT()
in Matlab after the function has been imported.
Step 3: The Pendulum Period Equation
With the periods of each pendulum selected, the next step is to figure out the lengths and release angles of the pendulums. In order to do this, we'll take a look at some equations.
The equation for the period of a pendulum is given by
T=2*pi*sqrt(L/g)*K(θ).
Here is a figure demonstrating L and θ. R and S are variables for the release mechanism, to be solved later.
Explanation of terms:
pi = 3._PHONE_..., etc.
L = the distance from the top of the string to the center of mass (the center of the pendulum bob, assuming the string is massless)
g = the acceleration due to gravity (approximately 9.81 m/s^2 or 32.17 ft/s^2)
θ = the release angle of the pendulum (the angle between the string when the pendulum is at rest and when the pendulum is released).
K(θ) = a correcting function that takes into account the effects of the release angle on the period. It is an infinite power series, but the successive terms grow very small very rapidly. A few terms suffice to get an accurate approximation.
 K(θ) = 1 + θ^2/16 + 11*θ^4/3072+173*θ^6/737280+...
For angles significantly less than 1 radian, K(θ) approaches 1 and can be neglected. To test whether an angle is "significantly less" than 1 radian, take the sine of the angle in question, then compare it to the original angle. If both the angle and the sine of the angle are nearly the same, then K(θ) can likely be neglected without greatly affecting the performance of the pendulum wave.
Assuming that the release angles are small and K(θ) can be neglected, then the only variable in the equation that must be solved for is L.
As somewhat of a perfectionist, I am against neglecting K(θ), even for smaller angles. I decided to do go the harder of the two routes, suffering the lengthier calculations for (hopefully) greater accuracy and a better-performing pendulum wave.
Why do some pendulum waves that ignore K(θ) yet have large release angles still look so good?
Here's a random example I found on YouTube:
In this example, all angles are constant, and thus K(θ) is also constant. As a result, all pendulum periods are equally wrong, making all of them look right relative to each other. For my pendulum wave, K(θ) will not be constant since the release angles vary. Because of this, not taking K(θ) into account will definitely affect things.
Step 4: More Math: Calculating Lengths of Pendulums
So far, we have the required periods needed for each pendulum. We also have one equation (from the previous step) which describes the period as a function of constants and two variables, L and θ:
T=2*pi*sqrt(L/g)*K(θ).
Since I want to view my pendulum wave from the top, and need the amplitudes of each wave to appear equal from that view, I further have the constraint:
L*sin(θ) = C
where C is the constant amplitude for all waves.
Here is a figure demonstrating this simple concept:
My method for solving the lengths of the pendulums was as follows:
1) I started with pendulum #18 in the series (the pendulum with the highest frequency and shortest length), choosing a the value that I wanted for the max release angle of the entire series. I chose pi/4 radians, or 45 degrees. All other release angle will be smaller than this value.
2) I plugged this value for the release angle into the pendulum equation, then solved L for


text:
Vacation Styles, Mental Well-Being and Work Motivation
Keywords:Mental - Wellbeing, Work Motivation, Workcation, Vacation, Gender
AbstractThe aim of the study was to scrutinize the differences in Mental Wellbeing and Work Motivation of corporate employees with respect to their gender and vacation styles, that is, workcation and vacation. The study also assessed the association between employees' work motivation and mental wellbeing. A descriptive study was carried out and the data was drawn from an online survey of 195 employees. The Work Motivation Questionnaire (Agarwal, 2012) and Warwick-Edinburgh Mental Wellbeing scale (Taggart, 2016) were utilized to gather the data. Independent samples t-tests were used to interpret the differences in well-being and work motivation of corporate employees with regards to their gender and vacation styles, workcation and vacation. Correlation and linear regression were both employed to evaluate the link and effect of work motivation on mental wellbeing. The findings indicated that there were no significant differences in wellbeing and work motivation of employees based on their vacation styles. There was a significant difference in the wellbeing of employees with respect to their gender and no significant difference was found in employees' work motivation based on their gender. Work motivation was found to be significantly correlated with mental wellbeing, accounting for 21.3% of the variance in mental wellbeing can be explained by work motivation.
How to Cite
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text:
m (corrected typo)
==Coat of arms==
The golden lion in the left of the coat of arms is the symbol of the [[Electorate of the Palatinate]]. The red dragon in the right is the symbol of the [[Waldsassen Abbey]], and symbolizes the margravate of Diepolding. Only the upper part of the dragon is shown (while the monastery had the full dragon as their symbol), to symbolize that the status of the monastery was reduced in 1803 from an imperial monastery to a subordinate of the Palatinate. The blue bar in the bottom right is the symbol of the landgraves of Leuchtenberg, parts of the historically owned by them was included into the district in 1972.


text:
State Assessed Property Appeals
In accordance with Article XIII, section 19 of the California Constitution, the Board of Equalization assesses certain public utility and other properties, specified below, and allocates the assessed values among the counties where the properties are physically located. Each county taxes the allocated value of state-assessed properties at the same rate as locally assessed properties.
State-assessed properties include:
- Pipelines, flumes, canals, ditches, and aqueducts lying within two or more counties and
- Property (except franchises) owned or used by regulated railway, telegraph, or telephone companies; railroad car companies operating on railways in the state; and companies transmitting or selling gas or electricity.


Return Number in Words Using JavaScript
One of the answers I've submitted on CodeWars that gets a lot of comments is in response to this prompt:
When provided with a number between 0-9, return it in words.
Input :: 1
Output :: "One".
If your language supports it, try using a switch statement.
The solution I've posted (which is very similar to the solution others have posted) is as follows:
switchItUp=n=>["Zero","One","Two","Three","Four","Five","Six","Seven","Eight","Nine"][n]
Since Arrays are indexed starting at zero and we can access any item in the array by its index, the way this works is by putting the equivalent word at each index, i.e.:
0 => Zero
1 => One
2 => Two
3 => Three
4 => Four
5 => Five
And the beauty of JavaScript is that we can pass a number to the switchItUp arrow function via the n parameter and it will pull out the equivalent item from the array at index n!
To break this out further, we can put this into a regular function:
function switchItUp (n) {
 const numbersAsWords = ['Zero', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine', 'Ten'];
 return numbersAsWords[n];
}
So if we pass in 5, for example, we look up index 5 in the array, which happens to correspond to 'Five' and so the function returns the string.
Of course, the variable is useless since it's only used one time, so we can remove it:
function switchItUp (n) {
 return ['Zero', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine', 'Ten'][n];
}
And this, besides not being an arrow function for the sake of brevity, is exactly the function above.
If I were going to bring something like this into everyday use, I'd add a Number.isInteger(n) check and I'd probably make sure the array contains the index being passed so there's no question that we'll get the number we want.
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Ice and Salt Preschool STEAM Activity
It's easy for kids to have fun with winter STEAM in this simple ice and salt activity. Kids can compete in ice cube races, observe changes in ice cubes as they melt, and discover how salt affects ice.
Salt and ice cubes experiment for kids
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Ice cubes are fun to use in a science activity to promote critical thinking and observation.
In this activity, kids will have an opportunity to make changes throughout the experiment to see how various factors affect the movement of the ice cubes.
STEAM = science+technology+engineering+art+math
Kids are engaging STEAM principles as they set design and set up the experiment (engineering), choose ice cubes of the same size (math), and observe how ice freezes and melts (science)!
Ice and salt experiment
Moving ice with a fan in a kids STEAM activity
1. Set up the activity
Set up the activity with a fan, a smooth surface, and ice cubes. You might go through some trial and error, as we did, in order to get results kids can easily observe and identify.
Here are some examples of our tests:
In our first attempt, we placed the ice cubes directly on the counter top.
For our second attempt, we placed the ice cubes on a glass cutting board (turned upside down as the underside is smooth).
We also tried various fans - a small table fan, a slightly larger 12 in. (30 cm) table model, and a floor model. The 12 in. (30 cm) sized fan is shown in the picture. It proved the best for moving the ice cubes.
2. Conduct experiments
Ice Races
Ice races science activity for kids
Place two ice cubes in front of the fan. Turn on the fan.
Ice and fan experiment kids science activity
See if one ice cube races ahead of the other!
Ice and Salt Friction
Ice with salt and fan STEAM experiment for kids
Place a row of salt in the path of one ice cube.
Observe the movement of the ice cube with salt and fan
The salt halts the progress of the ice cube!
 More science activities on our STEM to STEAM Pinterest board!
3. Observe results
 - We noticed that ice cubes melted faster in the path of the fan than ice cubes off to the side.
 - Salt inhibited the movement of the ice cube.
 - Ice cubes would slow or stop and then proceed after melting a bit, as if they moved on a cushion of water.
 Science for kids with salt and ice cubes
4. Make conclusions
Factors affecting the movement of the ice include:
 - type of surface where the ice cubes are placed
 - size of fan and strength of air flow
 - salt sprinkled in the path of the ice cube
 - ice melting during the experiment
This is an open-ended activity that encourages input and response from kids. As they play and learn kids benefit from exploring the challenges presented in this activity, and from the fine motor and sensory experiences it provides.
Simple STEAM activities are not only fun for kids but promote observation and discovery.
Kids STEAM activities
 (aff.)STEAM Kids 50+ Activities for Kids
Preschool Lesson Plans Winter Unit
Preschool lesson plan winter thematic unit
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text:
Dictionary of Netwar (Lenakel language)
- In this category:
- Language posters
This is the first ever extensive dictionary of Netwar language (western Tanna, Republic of Vanuatu) published online. It is the fruit of several years of my work among the inhabitants of the island of Tanna. It contains translations of local expressions, pronunciation recordings and photographic documentation. Its purpose is to help in the preservation of the language and in passing it to the young generation.
If you want to use this data in any way, or found a mistake, please, contact me first.
- n mountain, whose ridge goes all the way down to the seashore. cf.: 'tanepes'.
Speaker: Noël Yeru (Lowanatom)


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Was Orangeman Edward De Cobain jailed for a crime he didn't commit?
Was a Belfast MP who was given 12 months hard labour for acts of gross indecency framed? A BBC Radio Ulster documentary has chronicled the controversial life of Edward De Cobain. BBC NI's Political Reporter Stephen Walker has been following a story of power, sex and ultimately disgrace...
The new Public Records Office in Belfast's Titanic Quarter houses some fascinating documents.
The archived boxes of papers and files are a treasure trove for journalists, historians and anyone interested in researching the past.
It is home to many secrets.
Last month producer Robin Sheeran and I spent hours in the reading rooms going through court reports and witness statements from one of the most scandalous trials of the 1890s.
We were interested in the case of Edward Samuel Wesley De Cobain, a former MP and Orangeman who was found guilty of committing acts of gross indecency.
De Cobain was a colourful figure who had taken on the political establishment and surprisingly won the East Belfast parliamentary seat as an Independent Conservative in 1885.
A street preacher and a Orange Order Grand Master he often made anti-Catholic statements which meant he attracted headlines and enemies in equal measure.
He antagonised the Royal Irish Constabulary in 1886 when he criticised their handling of the Belfast riots. He also came into conflict with the city's industrialists when he promoted workers rights a stance that put him at odds with Sir Edward Harland who was Belfast's biggest employer.
In 1891 the East Belfast MP's life changed forever when the police issued a warrant for his arrest.
He was charged with committing acts of gross indecency with men at his Ormeau Road home and in a city centre office.
A senior police officer travelled to England to interview the politician, but he could not be found. The parliamentarian had escaped to France and Spain and eventually went to the United States of America where he became a street preacher in Brooklyn.
De Cobain finally returned home after two years of exile. By that stage, he had been thrown out of the Orange Order and had been expelled from the House of Commons.
The case came to court and on St Patrick's Day in 1893 his trial began. The former MP claimed he had been the victim of blackmail and his barrister alleged that the charges were as a result of a conspiracy.
The court heard how the MP had allegedly kissed a number of men and touched them inappropriately. The twelve man jury took just 40 minutes to return a guilty verdict. De Cobain was sentenced to twelve months imprisonment with hard labour.
Over a century on, a reappraisal of the case against Edward De Cobain has raised questions over his conviction.
Documents seen by the BBC contain allegations that some individuals were encouraged to make statements against the former MP and one individual was allegedly offered £500.
We contacted Phil De Cobain who is a businessman in North Yorkshire. He is Edward's great-great nephew and insists his ancestor could have been the victim of a conspiracy.
He said that "would be the view of the family".
He added that there was an "awful lot of contributory evidence to suggest that maybe he was framed".
Historian Nicola Morris who has researched De Cobain's life said the disgraced politician was convinced his enemies had conspired against him.
She told the BBC that many people would have been pleased to see him in prison.
She reveals in the documentary that "it is not beyond the realms of possibility that there was a set up".
Following his conviction in 1893 Edward De Cobain's public life was over and after he was released from prison he lived away from the gaze of publicity until his death in Bangor in 1908.
During his political career he was seen by many observers as a new kind of MP. He was backed by the Orange Order and supported working class unionism.
He had many roles aside from being a politician and was a firebrand, a street preacher and an agitator who was not frightened to take on the establishment.
Academics are divided on his contribution to Irish politics. Historian Eamon Phoenix says De Cobain had ability and amongst Conservatives and Unionists was "a potential leader".
Author and gay rights campaigner Jeff Dudgeon said De Cobain was "an outrageous hypocrite" who achieved little politically.
Nicola Morris said the high point of De Cobains career was his election victory in 1885 and he is famous for being convicted rather than for his political views.
However you judge Edward De Cobain, his life was certainly marked by power, scandal and disgrace. It is an intriguing episode from our Victorian past that has largely been forgotten and a fascinating story hidden in the archives that is worth re-telling.
"A very Victorian sex scandal". BBC Radio Ulster, Sunday 18 September 13:30.


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I need help on a math question.
Carly makes a rectangular pepperoni pizza using a 12-inch by 16-inch rectangular pan. If Kyle wants to make a circular pepperoni pizza that is approximately the same thickness as Carly's pizza using the same amount of dough, what should be the diameter of Kyle's circular pan? Please round your answer to the nearest tenth of an inch.
Thanks for helping!
3 Answers | Add Yours
For this question, you need to find the area of the rectangular pan of pizza first. As you know, you find the area of a rectangle by multiplying the two sides by one another. In this case, that is 12*16 = 192.
Then you have to figure the area of a circle. The equation for that is area = pi*r^2 where r is the radius of the circle.
So we know the area and we know pi so our equation is
192 = 3.14(r^2).
We divide both sides by 3.14 and we get
61.14 = r^2
Take the square root of 61.14, which is 7.8.
So the circular pan needs to be 7.8 inches in radius or 15.6 inches in diameter.
Here the volume of material of the dough is same and the thickness of the pizza is same but only the shape and area are different.The first one is rectangular and the second one is flat cylinderical.
Let the thicknes of the pizza be h inch
The volume of the rectangular shape = length*breadth*h =16*12*h...........(1)
The volume of the circular pizza = pi*radius^2*thickness=pi*(diamete/2)^2*thicknes.
Since the volume represented at (1) and (2) are same,
(pi*d^2/4)h = 16*12*h) The h gets cancelled. So solving for, d,
d = sqrt(16*12*4/pi) = 15.63528 inch =15.6 inch
When the thickness of the pizza as well as the amount of dough used for the rectangular and the circular pizzas are same, the areas of the pizza will also be same.
The area of rectangular pizza of 12" x 16" is given by the formula:
Area of rectangle = A = Width x Length = 12 x 16 = 192 sq.inch
The area of a circle is given by:
Area of circle = A = (pi/4) x d^2
Where: d = diameter of circle
Therefore diameter of circular pizza with area = A is given by:
d = [A/(pi/4)]^1/2 = 2 x (A/pi)^1/2
Value of A = 192 and pi is a constant with value 3.141
d = = 2 x (192/3.141)^1/2 = 2 x 7.818 = 15.636 = 15.6"
Diameter of circular pan = 15.6"
We've answered 318,957 questions. We can answer yours, too.Ask a question


text:
New AudioCue by Barco Improves Training Simulations with Precise Sound Cues
Barco has introduced a new audio system to enhance training simulations with precise audio cues that allow trainees to hear cues before they are in their field of vision, allowing them to react faster in training situations where every second counts. By providing very realistic sound, the system will thereby increase awareness during training and enhance the effectiveness of the session. This will provide needed improvements to simulations in industries such as security, military, rescue and healthcare.
The patented IOSONO CORE processing system renders real-time sound to produce very realistic results during training. The system generates sound from the exact location of the object in relation to the trainee's position—as it happens. Conventional channel-based systems don't offer this precision, making the training programs rigid and much less realistic.
The AudioCue offers a scalable solution supporting speaker arrangements from 8 to 128 audio channels that can be customized to fit any space. This allows the sound rendering to be based on the exact location of the speakers rather than on a pre-defined layout and eliminates the auditory 'sweet spot' in the system, thereby removing the risk of negative training. The system includes hardware and software processing capabilities that seamlessly integrate into any existing content or IG setup.
ABOUT THE AUTHOR
DIRECTOR OF MARKETING & SPECIAL PROJECTS
Adrienne is responsible for all inbound and outbound marketing efforts, website design and development, special events, and tradeshows.


annual' rate. For junior players who may play, say, one of the football codes in winter and cricket in summer, it would be important to note that a rate was a 'seasonal' incidence rate (not including injuries from the other sport) rather than an 'annual' incidence rate (which would include injuries sustained while playing other sports).
 2. For a tournament that lasted for, say, 2 months, injury rates could theoretically be multiplied by six to give an 'annual' injury incidence based on the hypothetical situation of a similar tournament being indefinitely played six times per year. However, in reporting tournament injury incidence (eg, for a World Cup, or in a domestic T20 competition), it may be preferable to use match injury incidence rates rather than annual incidence rates.
Definition of cohorts
The cohort to be followed for a given team should be referred to as the 'squad'. A match-day team generally consists of 11 players (11 active players and the 12th man), whereas a squad for a team contains a varied number of players. The squad to be followed can consist of any number of players, which should be recorded for all times of surveillance (ie, for the entire year if annual surveillance is being undertaken).
A squad should be chosen at the start of the surveillance period, determined in advance. Therefore, injury rates will consider those players who become injured as well as those who avoid injury, and it is possible that a squad will contain injured players at the start of the surveillance period. A squad might consist of a team's designated list of contracted or registered players, or a group of players selected for a particular tournament. However, players may need to be added if they are chosen to play for the team from outside the initial squad. Similarly, players who are de-registered, or are dropped from a contracted professional or international squad, should be removed.
The definition of a squad member for a team may be varied, but an example is as follows:
 1. Any player under contract to the team in question (or a 'registered' player at amateur level).
 2. Any other player who plays in the team first XI (not including 12th man or a fielding substitute) or tours overseas with the team, from the time of his/her first game (or the first tour match) until the end of the cricket year or season (when a new round of contracts is awarded).
For tournament injury surveillance, if the cohort is determined to be the selected squad for the tournament, it should be noted that there would be a strong bias towards injured players not being selected (although occasionally they are, in the hope that they may become fit early on during the tournament). Injury prevalence for tournaments with cohorts chosen in this fashion are likely to be lower than injury prevalence for contracted players on an annual basis, as the tournament cohort is biased against players suffering from pre-existing injuries (who make up a high proportion of the injured cohort when considering injury prevalence).
For additional information pertaining to injury surveillance systems, refer to online supplementary appendix II.
This consensus statement has evolved from the original recommendations of 2005. The evolution of this consensus statement is from being prescriptive ('all studies should use the following methods') to descriptive ('all studies should conduct the most complete injury surveillance possible and clearly describe the methodology'), emulating statements such as PRISMA24 and STROBE.25
A greater motivation for an updated consensus statement is to lead to consistency within the sport of cricket as well as between sports, using definitions that may be compared to those used in other sports. There has also been a greater appreciation that it is impossible and unwise to try to formulate a fixed set of definitions to suit all types of studies within a single sport. Given the concession that definitions will therefore need to vary, the focus of this consensus statement has moved to clarity in choosing and reporting methods used.
The difficulty in providing a single injury definition that will suit all purposes with respect to a sport or injury surveillance system within a sport has been discussed.12,13 To illustrate this argument in a cricket context, consider how shoulder injuries might best be defined in the following circumstances:
 1. To determine whether certain countries/teams or years had higher rates of shoulder injuries than others, a 'time-loss' injury definition may be preferable, as it is the most easily captured, objective and reliable indicator of a significant injury;
 2. To determine shoulder injury rates during a cricket tournament, a 'medical presentation' injury definition may be preferable, as all teams will have medical and/or physiotherapy staff who could hopefully keep consistent data over a limited time period during a tournament;
 3. To determine shoulder injury rates in amateur cricketers, a 'player-report' definition based on physical symptoms may be preferable, as amateurs may or may not have presented to any medical staff with their symptoms but should be able to recall symptoms that have occurred within a reasonable time period, for example, the past year;
 4. To study the development of pathology in the shoulder and its relationship to symptom development in cricketers, a study using an 'abnormal imaging' injury definition, based on ultrasound scan or MRI findings performed on cricketers without shoulder symptoms, could be employed.
Although time-loss definitions are preferable to medical attention injuries in many circumstances, there is one emerging injury category of importance where a medical attention definition is preferable: concussion and head impact injuries. Given the long-term concerns relating to concussion, it is recommended that injury surveillance systems keep a record of all head/neck/helmet impacts irrespective of whether or not they meet the threshold for a concussion diagnosis. That is, any impact to the head or neck region which would prompt the medical staff to ask the player whether they had suffered any symptoms (ie, generate medical attention based on the observed event rather than any symptoms), even if the player claims to have not suffered any injury or symptoms.
Injuries per number of player hours is, in theory, most accurate, but its relevance has been lessened by the rise of T20 cricket.4 A day in which a T20 game is scheduled generating the same number of injuries as a day in which a 50-over match is scheduled would appear to have an injury incidence that was 2.5 times higher, because there were fewer overs bowled. Therefore, a unit of injuries (numerator) over player days (denominator, considering 11 players in action per day) could be used, which is simpler and more representative of actual risk (in a given time period).4 This is analogous to comparing injury rates of various Track athletic events in a per event rate (100 m=one event; Marathon=one event) rather than a rate per hour of competition participation, which would make sprint events appear to be far riskier than distance events.
There are other circumstances specific to cricket where standard definitions are problematic. Within the realm of T20 cricket, some countries have moved to a 'franchise' model of T20 teams which are contractually and operationally distinct from the traditional domestic teams, whereas other countries still combine contracts to play T20 and longer forms of cricket for a single team. It would be inappropriate to state that T20 team cohorts should be either distinct from or combined with longer form surveillance cohorts, as the situation in different countries should lead to a different approach.
A somewhat unique cricket problem when assessing availability to play is the requirement of all players to be able to bat, but only some players need to bowl. The player who is fit to bat but not fit to bowl may be available for selection if their batting ability warrants, but not if selection would rely on also being fit to bowl. For some players who are 'part-time' bowlers but are unfit to bowl, it can be difficult and somewhat subjective to determine if they are missing a game whether this is truly due to injury or selector preference. This is particularly the case where a player continues to play as a batsman only and remains unfit to bowl. A guideline from these definitions is that this would equate to being unavailable through injury for a 'regular bowler', but we concede that these determinations may need to be made on a case-by-case basis. The difficulty is increased if a player is available to bowl but with workload limits recommended by medical staff that effectively result in non-selection in the longer forms of the game.
This complexity of role in cricket has led to our recommendation that injury surveillance systems avoid 'training time-loss' definitions, as many players regularly train in partial fashion. This would render the concept of a 'missed training session' to be too difficult to determine on too many occasions. For a 'general time-loss' injury, we have opted to recommend a daily binary status of 'considered fit to play a cricket match/not fit to play a cricket match' with the role and type of match necessarily being player-specific (ie, what type of match and in what role would a player be expected to be next fit for?).
In conclusion, these new consensus definitions are presented to offer greater flexibility to researchers at choosing methods which suit their study type and encouraging greater rigour in reporting to allow comparison between studies within cricket, and between sports.
View Abstract
Supplementary materials
 - Supplementary Data
 - Twitter John Orchard _USER_, Craig Ranson _USER_, Isabel Moore _USER_, Jon Patricios _USER_, Nicholas Peirce _USER_ and Caroline Finch, _USER_
 - Competing interests JO (and other authors affiliated with various national cricket boards and associations) declare an interest in being paid either salary or consultancies to provide services for the various associations that they are affiliated with. However, no author was funded or paid specifically to directly work on


text:
A plane that convert CO2 TO O in the air.
The laser plane main job is to save the planet though the from of flight. This plane will be autonomous when flying though the air and will be able to avoid object around it if need. The plane will be powered by solar panels that are place on top of it wings. The solar panels main goal is to keep the plane in the air 24/7. The solar panels will be able to power the lasers. These lasers will convert the CO2 into oxygen. The plane will be able to be controlled by a command center if need when a storm is near by. This plane will tackle the CO2 problem that in the air directly. This will solve many air quality problems.


text:
Background: Hypocholesterolemia is common among tuberculous patients and is associated with mortality in miliary cases. Some in vitro studies have shown that cholesterol is necessary for the good functioning of macrophages and lymphocytes.
Study objectives: To determine whether a cholesterol-rich diet could accelerate sputum sterilization in patients with pulmonary tuberculosis.
Design: An 8-week follow-up, randomized, controlled trial carried out from March 2001 to January 2002.
Setting: A third-level hospital for respiratory diseases in Mexico City.
Patients and interventions: Adult patients with newly diagnosed pulmonary tuberculosis were hospitalized for 8 weeks and randomly assigned to receive a cholesterol-rich diet (800 mg/d cholesterol [experimental group]) or a normal diet (250 mg/d cholesterol [control group]). All patients received the same four-drug antitubercular regimen (ie, isoniazid, rifampin, pyrazinamide, and ethambutol).
Measurements and results: Every week, a quantitative sputum culture and laboratory tests were done and respiratory symptoms were recorded. Patients in the experimental group (10 patients) and the control group (11 subjects) were HIV-negative and harbored Mycobacterium tuberculosis that was fully sensitive to antitubercular drugs. Sterilization of the sputum culture was achieved faster in the experimental group, as demonstrated either by the percentage of negative culture findings in week 2 (80%; control group, 9%; p = 0.0019) or by the Gehan-Breslow test for Kaplan-Meier curves (p = 0.0037). Likewise, the bacillary population decreased faster (p = 0.0002) in the experimental group. Respiratory symptoms improved in both groups, but sputum production decreased faster in the experimental group (p < 0.05). Laboratory test results did not differ between the groups. Conclusions: A cholesterol-rich diet accelerated the sterilization rate of sputum cultures in pulmonary tuberculosis patients, suggesting that cholesterol should be used as a complementary measure in antitubercular treatment.
It's been speculated, notably by Dr. Uve Ravnskov, a noted skeptic of the cholesterol hypothesis of heart disease, that cholesterol protects against infections. There are good mechanistic reasons for thinking so; this passage from the first link explains:
Cholesterol constitutes up to 30% of the total lipid content in the cell membrane, and participates in the fluidity of this structure.10Consequently, cholesterol is involved in the activity of membrane-bound enzymes and membrane functions such as phagocytosis and cell growth.11In this context, Drabowsky et al12demonstrated that cholesterol content in the cell membrane of human lymphocytes is important for their cytotoxic function. Heiniger and Marshall13found that cholesterol participates in the differentiation and proliferation cycles that convert lymphocytes into cytotoxic cells. Moreover, in a work published by Gatfield and Pieters14a clear derangement of the ability of the macrophage to phagocytase mycobacteria was observed when they were depleted of cholesterol.
In TB patients, low cholesterol is strongly associated with mortality. The above study looks as if it proves a causal connection: more cholesterol, better immunity.


text:
- Study at Deakin
- Campus life
- Industry and community
- About Deakin
Pure basic research is experimental or theoretical work which is undertaken primarily to acquire new knowledge without a specific application in view, and is carried out without looking for long term economic or social benefits other than the advancement of knowledge. It includes most humanities research.
Strategic basic research is experimental or theoretical work which is undertaken primarily to acquire new knowledge without a specific application in view, and is directed into specific broad ares in the expectation of useful discoveries. It provides the broad base of knowledge necessary for the solution of recognised practical problems.
Applied research is original work which is undertaken to acquire new knowledge with a specific practical application in view. Applied research is undertaken to determine possible uses for the findings of basic research or to determine new methods or ways of achieving some specific and pre-determined objective.
Experimental development is systematic work, using existing knowledge gained from research and/or practical experience, for the purpose of creating new or improved materials, products, devices, processes or services. In the social sciences, experimental development may be defined as the process of transferring knowledge gained through research into operational programs.


text:
This study was conducted to demonstrate the effectiveness of a modification of lime stabilization by the incorporation of pulverized fuel ash (PFA) for disinfection of sludge. The modified treatment is economic in terms of lime utilization and uses another waste product, PFA, which would also require disposal. Intestinal pathogens are the most probable pathogenic organisms present in the sludge. Several species of intestinal pathogen were examined for their ability to survive in raw sludge and then subjected to disinfection. The effect of the chemical mixture was attributed to the high pH produced and maintained, as heat production in the modified process was minimal. A mixture of 60% sludge (600 g/kg): 40% CaO/PFA (44.44 g/kg/355.56 g/kg) with the ratio CaO:PFA 1:8, was shown to be able to prevent the growth of bacterial pathogens and maintain a pH above 11.0 for at least 7 d. Although further study concerning texture and other physical properties is required, a modified sludge treatment with this relatively low proportion of lime was found to be suitable for landfill or land reclamation as far as its bacteriological disinfecting quality is concerned.
ASJC Scopus subject areas
- Environmental Science(all)


Challenge 5: Help the Policemen Catch the thieves!
Given a number of policemen and thieves, calculate the maximum number of thieves that can be caught.
Problem Statement
Implement a function that calculates the number of thieves that can be caught.
Input
An array of size n where each element in the array contains either a policeman (P) or a thief (T).
Each policeman can catch only one thief and a policeman cannot catch a thief who is more than k units away from him.
Output
The maximum number of thieves that can be caught.
Sample Input
 policeThiefArray[] = {'P', 'T', 'T', 'P', 'T'},
 k = 1.
Sample Output
 2
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