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Global Food Encapsulation Market Segmentation By Technology (Nano Encapsulation, Micro Encapsulation, and Hybrid Technology), By Material (Proteins, Emulsifiers, Lipids, Polysaccharides and other), by Core Phase (Minerals, Organic Acids, Vitamins, Enzymes, Probiotics, Additives, Essential Oils, Prebiotics and others), and by Regional Analysis (North America, Europe, Asia Pacific, Latin America, and Middle East & Africa) - Global Industry Analysis, Size, Share, Growth, Trends, and Forecast (2022 – 2027)
Published: January, 2022
ID: 1036
Pages: 175
Formats: report pdf report excel report power bi report ppt
Food Encapsulation Market Size, Growth, Forecast (2022-2027)
The global Food Encapsulation Market size was estimated to be US$ 9.9 billion in 2021, and it is foreseen to reach a valuation of US$ 14.1 billion 2027 with an annual expansion pace of 7.5% between 2022 and 2027.
Food Encapsulation Market
Market Overview:
Food encapsulation used to preserve food and maintain the shelf life of food products by enhancing its taste, flavor and color. It also helps preserve and stabilize food ingredients in their original form. However, food manufacturers should focus on combining encapsulation technology and wall material to improve product shelf life in various applications, such as animal nutrition products, beverages, and dairy products. These ingredients are essential to guarantee the flavor, shelf life and taste of finished products. Food encapsulation makes it easy to coat food ingredients like raisins, fats, flavors, acidulants, and whole ingredients.
Recent Developments in Food Encapsulation Industry:
 - In May 2017, Lycored (Israel) entered a joint venture with a biotech company, Algatechnologies (Israel), to distribute Algatech's AstaPure in the form of pearls, which will help increase the brand's commercial reach for this line. of products in North America Market.
 - In November 2019, Givaudan announced the launch of a new fat encapsulation technology that is believed to reduce the fat content of meat substitutes by 75%.
Food Encapsulation Market Growth:
The Asia Pacific food encapsulation market is expected to witness the fastest growth of over 8% between 2020 and 2026. Rapid growth in the food industry, coupled with growing demand for functional food products, will lead to a share regional market.
REPORT COVERAGE:
REPORT METRIC
DETAILS
Market Size Available
2021 – 2027
Base Year
2021
Forecast Period
2022 - 2027
CAGR
7.5%
Segments Covered
By Technology, Material, Core Phase and Region
Various Analyses Covered
Global, Regional & Country Level Analysis, Segment-Level Analysis, DROC, PESTLE Analysis, Porter's Five Forces Analysis, Competitive Landscape, Analyst Overview on Investment Opportunities
Regions Covered
North America, Europe, APAC, Latin America, Middle East & Africa
Market Leaders Profiled
Advanced BioNutrition Corporation, ABCO Laboratories Inc, Aveka Group, Cargill Inc, Balchem Corporation, Encapsys Microencapsulation, Blue California, FrieslandCampina Kievit, Coating Place Inc, Firmenich Inc and Others.
Drivers:
Consumers are becoming health conscious and therefore the demand for nutrient rich products has increased globally and can be met by encapsulating food. The principal aspects of the global food encapsulation market are the rise in call for functional foods and the surge in the health-conscious consumers worldwide. The prevalence of diseases such as obesity and diabetes are increasing worldwide; therefore, people become more aware when choosing their food and drink. Also, the increasing demand for ready-to-eat food could also boost the world market in the future. This is expected to drive the global food encapsulation market in the near future. As a result, consumer demand for specialty foods has increased significantly worldwide, providing new products. Consumer buying behavior has changed significantly in recent years. This is mainly due to increased disposable income and increased consumption of healthy foods. This may be due to increased consumer awareness that drives food awareness demand and increased consumer consumption of food and beverages, and demand for food that provides additional benefits is increasing at a faster rate, especially in economies emerging. However, due to a busy life, people opt for prepared meals. These foods fall into the category of ready-to-eat foods; they need a certain shelf life to preserve the taste, flavor and color of food. Furthermore, prepared meals could drive the food encapsulation market in the coming years. With the increasing number of diseases like diabetes and obesity worldwide, people are becoming more aware of their food and drinks. These are ready-to-eat foods that require a certain shelf life and must retain the flavor, color and taste of the food. The increase in the number of health-conscious consumers, the increase in the consumption of functional foods and the increasing demand for ready-to-eat foods are among the main drivers of the global food encapsulation market.
It is also increasingly used as an encapsulated sweetener in confectionery products such as candy and gum. Encapsulation technology allows the core product or active material to be designed to be released at a specific temperature or time required after consumption. Besides, food and beverage processors tend to secure a competitive advantage by applying encapsulation to various products. The benefits of encapsulation, such as the controlled release of ingredients, are driving business expansion. Time controlled release of constituents is the preferred method for functional food products. Changes in lifestyles are leading to wide diversification of food products and triggering demand for ready-made meals, thereby stimulating demand for food encapsulation. Controlled release of ingredients over time is the most preferred method for nutraceuticals. Using encapsulation technology, the base product or active ingredient can be designed to be released at a specific temperature or at the required time after consumption. The benefits of encapsulation, such as the controlled release of ingredients, drive the company's expansion. Additionally, food and beverage processors tend to increase the application of encapsulation in various products to gain a competitive advantage. Growing consumer preference for healthy and convenient foods due to awareness. Food encapsulation is widely adopted in industries such as meat, poultry, beverages, and seafood. Due to the busy life schedule, consumers have a higher demand for prepared foods. The demand for healthy, tasty, and nutritious products by health-conscious consumers can be met through food encapsulation, leading the overall market. The global food encapsulation market has strengthened as demand for prepared foods increases. On the other hand, emerging economies offer enormous growth opportunities due to better economic conditions and greater government support.
Restraints:
A limiting factor in this market is maintaining food stability during processing and packaging. Another limiting factor is the size of the capsule. These technologies are in their infancy, and ongoing technological advances have yet to attract much attention. This negatively affects the growth of the market. The difficulties associated for maintaining the stability for food encapsulation during the processing and packing of the food is expected to hamper the business growth.
Food Encapsulation Market Segmentation Analysis:
The global food encapsulation market is classified by technology, type of material and core phase.
Based on the technology, the market is divided into nano encapsulation, micro encapsulation, and hybrid technology. Microencapsulation is the process of packing or coating small solid, liquid, or gaseous particles with a secondary material to produce microcapsules with a diameter of 1 to 1,000 microns. Microencapsulation technology helps control the release and strengthening of functional food and beverage ingredients such as flavors, vitamins, antioxidants, fatty acids, and minerals.
Depending on the type of material, the market is divided into proteins, emulsifiers, lipids, polysaccharides, and other materials. Polysaccharides are compositions of repeated monosaccharide units linked by glycosidic bonds. Polysaccharides are chemically easily deformable and offer numerous textures and viscosities. The polysaccharide sector occupied the largest market for roofing material in 2018 and is expected to follow the same trend by 2025.
Based on the core phase, the market is classified into minerals, organic acids, vitamins, enzymes, probiotics, additives, essential oils, prebiotics, and other substances. Vitamins are functional ingredients that are used in food due to the specific nutritional properties of various parts of the human body. Therefore, encapsulation is primarily applied to vitamins for specific effects. Depending on the vitamin, the trend for flavor encapsulation to achieve long-term controlled release of flavors is increasing.
Geographical Segmentation Analysis:
 - North America - the United States and Canada
 - Europe - United Kingdom, Spain, Germany, Italy, and France
 - The Asia Pacific - India, Japan, China, Australia, Singapore, Malaysia, South Korea, New Zealand, and Southeast Asia
 - Latin America - Brazil, Argentina, Mexico, and Rest of LATAM
 - The Middle East and Africa - Africa and Middle East (Saudi Arabia, UAE, Lebanon, Jordan, Cyprus)
Regional Analysis:
North America contributed the largest share in the worldwide market for food encapsulation. However, the market for finished products is saturated and the market is slow. Asia Pacific is emerging as the fastest-growing market due to the region's fast food industry. Besides, increased financial stability and


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When you are studying for the car theory test you will need to study and practice 14 car theory test subjects. These subjects range from your attitude towards road users around you to the rules regarding the motorway.
Here we cover the fourth subject (in alphabetic order)
Safety Margins – a total of 33 theory test car questions, safety margins consists largely of stopping distances, driving in fog and icy roads. The DVSA put these car theory test topics together in order to ensure that learner drivers will be able to deal with dangerous road situations like icy roads and understand the precautions that they should take when driving in these conditions. Of the 33 questions one of the least understood car theory test question is listed below
How can you avoid wheelspin when you're driving on an icy road?
- Drive at a slow speed in the highest gear possible
- Use the parking brake if the wheels start to slip
- Brake gently and repeatedly
- Drive in a low gear at all times
Lets start by explaining what a wheelspin is. A wheelspin is when the wheels on your car are spinning uncontrollably fast losing so much friction that the car isn't actually moving. This can happen if there is too much acceleration going on or in icy conditions when the wheels are struggling to grip the road. If you find yourself driving in icy conditions and the wheels start to spin too fast then the driver needs to able to change the situation. Before that is explained it is important to understand the difference between driving in high gears and driving in low gears. 1st gear is considered the lowest gear and 5th gear (6 in some cars) are considered a high gear. When you drive in 1st gear the wheels are spinning the fastest they can and in 5th gear they are spinning the slowest they can. So when you are moving off in icy conditions, it is always a good idea to drive in as high as gear as possible i.e. 2nd gear or even 3rd gear as that way the wheels will spin slower meaning that the vehicle will have more road friction. Hence the answer to the theory test car question above is 'drive at a slow speed in the highest gear possible.' If you 'use the parking brake if the wheels start to slip', then the car can skid. If you 'brake gently and repeatedly' then the car can also skid as its easier to skid when you over brake in icy roads. 'Driving in a low gear at all times' mean the wheels will spin too fast and the car will struggle to gain friction.
Another car theory test question that causes some confusion is as follows:
You're following other vehicles in fog. You have your headlights on dipped beam. What else can you do to reduce the chances of being in a collision?
- Keep close to the vehicle in front
- Use main beam instead of dipped headlights
- Keep up with the faster vehicles
- Keep a safe distance from the vehicle in front
Before trying to work this question out it is important to understand what dipped beam is and this seems to create a lot of confusion with many learner drivers. Cars have different front lights, and it is important to know the difference between them. Sidelights are basically the weakest lights and you can use them in the day or when it is slightly gloomy in order to make yourself more visible to oncoming traffic. They are not powerful enough to benefit the driver so are used more to aid the visibility for other road users. Headlights (or dipped beam) are the vehicles most commonly used lights. These headlights point towards the ground in order to prevent dazzling other road users but being strong enough to use at night and in normal darkened situations. Main beam or (full beam) are the most powerful front lights and are commonly used when driving at night in country roads that do not have any lighting on the road. You should switch them off when you see oncoming traffic or when you're following traffic as you risk dazzling the drivers if you don't. Fog lights are an optional extra that some cars but not all have built in. They are to be used in foggy conditions, heavy rain or snow. They are designed to penetrate fog rather than reflect the fog back to the driver.
Going back to the theory test car question, if you 'keep close to the vehicle in front' then you run the risk of the car in front stopping in an emergency which could mean that you crash into the car in front. If you 'use main beam instead of dipped headlights' then the fog could be reflected back to the eyes of the driver. This answer seems to be very popular amongst many learner drivers but in this case it is not the correct answer. 'Keep up with the faster vehicles' is also unsafe as you may be driving faster than what is safe for the road conditions. The correct answer to the car theory question above is 'keep a safe distance from the vehicle in front.' By keeping a safe distance from vehicles in front in foggy conditions, you will have more time to react to changes, see a lot more in front as well as giving less pressure to the vehicle in front of you thus making you a better and safer driver.

source: openbmb/Ultra-FineWeb


text:
Kelly Arora teaches holistic care principles to pharmacy students
Sixteen years ago, Kelly Arora was diagnosed with rheumatoid arthritis. Her own experience in the health care system and her understanding of spirituality led her to teach courses on faith and healing for future medical professionals.
"What I found missing was the psycho-spiritual component of care," said Arora, affiliate faculty in the School of Pharmacy. "When we operate in a biomedical-only model, we are likely to miss a lot of that. It is very easy to have your body cared for and not always the rest of you."
Arora teaches the Jesuit concept cura personalis - care of the whole person – in her class Faith Traditions in Health Care. This third-year pharmacy course focuses on how patients make meaning of illness and injury, how they cope, and how religion and spirituality affect their healing.
Students learn about the parallel chart, a collection of subjective information about themselves as caregivers. Arora teaches that this should accompany the traditional medical chart to provide for the best possible interaction between pharmacist and patient.
"This class really aligns with the goals of the pharmacy program; to develop pharmacists who are respectful of other people's beliefs and values, who take into account the whole person and who demonstrate compassion and empathy," said Arora.
Arora's students use team-based learning to collaborate on ideas for case studies and in-class assessments. Of utmost importance is treating the patient as a person, said Arora. Her students write out philosophy of care statements, in which they incorporate their own key values and clearly define how they want to practice medicine. The class also focuses on self-care, mindfulness, meaning-making practices and reflective exercises.
In addition to the pharmacy course, Arora teaches an undergraduate course called Faith and Healing, in Regis College.
"These classes beg the question, 'what heals us?' Is it God? Is it doctors? Is it ourselves? Is it other people?" said Arora. "We don't heal alone. We heal in relationship with the people in our lives, including health care providers. Where is God in that too?"
Discover cura personalis in Regis' pharmacy program.

source: m-a-p/FineFineWeb


Give to Lehman
Lehman College
Vision, Purposes and Professional Commitment
Vision and Purposes
Education has the power to transform individuals and communities. Because we believe in the capacity of all individuals to attain their educational, occupational and personal goals, we understand education as an ongoing and transformative process that supports lifelong growth and the development of people, communities, and institutions.
The Core Purposes of Lehman College's School of Education are to:
 - understand and affirm linguistic, ethnic, and cultural diversity as foundations for learning, teaching, counseling, and leading in educational settings;
 - create educational settings where human relationships are nurtured and where students acquire academic and personal/social skills that prepare them for success;
 - create educational cultures, climates, policies, and practices that are safe, equitable, and responsive to changing needs.
To enact these purposes, we recruit and retain faculty and students who are ethnically and culturally diverse, globally aware, knowledgeable, and principled.
Professional Commitments
We draw upon a richly diverse body of knowledge and experience to inform our practice as teacher, school counselor, and school leader. We come together at the interstices of numerous disciplines and practices and multiple perspectives and ways of knowing because we share a common commitment to urban transformative education. Education is about ensuring that every student achieves his or her academic, career, and college goals.
 - We believe that quality learning for students depends on quality learning for educators. Each educator preparation program must identify essential knowledge, skills, and dispositions and assess them in their candidates in order to ensure that graduates will have a positive impact on PreK-12 student populations.
To be transformative, learning is socially constructed, ideally within a network of caring and supportive relationships. Although we are housed in different places within and outside of the College, and although our knowledge bases and philosophies of education may differ, we are all committed to excellence in teacher, school counselor, and school leader education.
 - We believe that the School of Education is responsible for preparing teachers, school counselors, and school leaders who are capable of transforming the lives of students.
To make a difference in the lives of students, each of our programs is designed to help graduates develop a sense of efficacy and a belief that they can be agents of transformation.
 - We believe that the diversity of our candidates, which reflects the borough of the Bronx and surrounding communities, is essential to the quality of our programs.
Lehman College students come from diverse ethnic, cultural, linguistic, social class, age, religious/spiritual, gender, sexual orientation, gender identity/expression, language, ability/disability, immigrant cultural communities and varied family types. Many of our candidates are from immigrant families, have acquired English as a second language, and are first generation college students. Their perspectives as emerging teachers, school counselors, and leaders have a profound impact on the School of Education. The children, adolescents, adults, and families that our pre-service and in-service educators serve also shape our identities as teacher, school counselor, and leadership educators. As we disaggregate data from our interventions using equity-focused assessment, we find compelling evidence of the importance of our work.
 - We believe in the rich contribution of each of our educational partners in transformative practice.
The School of Education serves the Bronx and our surrounding communities through partnerships and outreach programs that engage community leaders, teachers, school counselors, school administrators, families, and PreK-18 students in activities and projects that enhance the lives of individuals and the community as a whole.


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Alison McInnis is conducting a research project on oral language skills and executive functions in children with ADHD, and is looking to recruit participants between 9-14 years of age. The study involves assessment of basic and higher level oral language skills, reading, writing, and executive functions (e.g., working memory, problem-solving).
Alison is a registered Speech-Language Pathologist and so can offer parents a clinical report about their child's language, reading, and writing skills, which could be of benefit at their child's school. In her past research experience, parents have been quite positive about having oral language skills assessed as this is typically not a focus of assessments their children have received at school. Also, in older children, this area is often overlooked and yet many children with ADHD have issues with oral language skills that also underlie their academic difficulties.


I didn't know it is PH000 until some comments here save my time. Thanks guys
 wanhor - Reply
 I wonder if the two screws shown on the picture are not inverted. It would seem logical to me that the longest (1.7mm) screw be placed on the upper hole, (where there is the yellow circle) ie on the hole where there is extra thickness (of the gold plated grounding contact sheet metal) in the sandwich. I have not checked, however, I just put the screws in the same location as found.
 Yves - Reply
 5. Carefully push the pressure contact away from the battery connector until it slides free from its position. Remove the pressure contact. Remove the pressure contact.
 - Carefully push the pressure contact away from the battery connector until it slides free from its position.
 - Remove the pressure contact.
 6. Use a plastic opening tool to gently pry up the battery connector from its socket on the logic board. Place the tip of the tool between the loudspeaker enclosure and the metal cover of the connector, and lift the bottom edge of the connector first. The battery connector comes off vertically from the logic board. Do not apply force sideways.
 - Use a plastic opening tool to gently pry up the battery connector from its socket on the logic board.
 - Place the tip of the tool between the loudspeaker enclosure and the metal cover of the connector, and lift the bottom edge of the connector first.
 - The battery connector comes off vertically from the logic board. Do not apply force sideways.
 - Be careful not to pry at the battery connector socket itself, or it may detach from the logic board. There are four very small solder points awaiting this mistake!
 No idea what exactly this step means. I just pulled the battery connector without trying to move the pressure contact. Installed new battery, plugged in connector and aligned the pressure contact slightly for the screw to fit.
 Got a big scare as the phone would not connect to the cell network at first boot, only WiFi. Shut it off and when it rebooted it seemed to work. WIll probably know in a day or so if everything works fine or if there are interference issues, etc.
 andries - Reply
 This is normal ... removing the battery resets internal clock to start value and your provider doesn't accept that, hence no network.
 Going online through wifi or manually setting date right corrects this after a reboot.
 Dreetn -
 I also accidentally removed the pressure contact. I put it back in place as best I could during reassembly and so far haven't ran into any problems.
 Maynard Stevens - Reply
 The black & copper contact piece is missing from my iPhone. Does that explain why my phone won't restore and keeps re-booting? I have tried every kind of restore with no luck. Any ideas?
 ozarkana - Reply
 After reassembling the iPhone I the GSM connection wasn't working. After cleaning all parts with isopropyl alcohol it still didn't work. What solved my problem was to turn on WiFi and then synchronizing the date and time which was set to 1970-01-01. After a reboot everything worked just fine. :)
 Florian - Reply
 I had the same problem. Thanks for the solution!!
 Manolis Mylonakis -
 thanks for this!
 Bill McNamara -
 The black ground contact needs still more "flagging." This is a simple metal strip that is attached ONLY by the 1.5mm (upper) screw. It will help if you look at it before you remove the upper screw. Notice the gold contact arm and point. That contact point must be in a plane above every other surface inside the device when you replace the battery connector, because it makes a ground contact with the metallic inner surface of the device back plate.
 When I replaced it, I used the Pentalobe driver to line up battery connector and ground contact with the screw socket post. I then attached the 1.7mm (lower) screw loosely, removed the Pentalobe driver gently, and inserted the 1.5mm (upper) screw into the assembly. There is a tab on the ground contact that helps it align properly once pressure begins to applied. I completed driving the upper screw, pressing lightly with the spudger on the battery connector plate to make sure it was seated on the pressure contacts. Finally, I completed driving the lower screw.
 Matt McCaffrey - Reply
 I didn't find any need to remove the pressure contact. I just pried the battery connector up (gently) with a spudger and left the pressure contact in place. Connected the new battery and aligned the pressure contact screw hole. Replaced the screws, finished reassembly and all was good.
 Roger Mercer - Reply
 After reassembly, the CELL CONNECTION WASN'T WORKING. You might need to slightly bend the contact in step 5 up just a little, so it will make contact with the metal back plate. Did that and it worked perfectly.
 Great kit, great instructions, thanks!
 AirPhonesApp - Reply
 all those teeny screws...and the world is so...well...BIG!
 go slow and put those parts INTO something...
 putting them "on" something will just cause heartache and and an infected bladder...
 °¿°
 after a lot of froofroo and very errant iphone behaviour problems, i concluded that that tiny grounding piece must be being lazy as hello. i spread it out a bit to ensure a better contact with the back plate and everything appears to be working smoothly.
 did this repair, as well as the battery replacement...GTG!!!
 spoke too soon, i 'spect...random reboots persist.
 richard - Reply
 Just went through the replacement and the battery "plug" (step 5) on my replacement battery was slightly misaligned relative to the metal plate used to screw it onto the board. The plastic and "gold" "plug" was slightly askew on the metal plate, which meant that when the plug was inserted, the screw holes (step 4) were poorly aligned.
 I managed to pull everything back into line using the screws, but the QC on these replacement batteries is a bit suspect.
 cvdwl - Reply
 Guess what happens when you rotate that ground connector 180 degrees...it grounds what I deduced to be the heat sink of the power amplifier for the speaker! So it is silent. It took me a couple of attempts to discover this as I was distracted by the new speaker not sitting down properly and a little dot of stuff under the main connector stuck to the pins. The latter was cleaned-off with a pin under 5x magnification followed by some isopropyl alcohol.
 I suggest that Step 5 is more explicit about the orientation of this ground connector. It's only obvious after a really close look and if one has a lot to do like I did, it's a long time before one comes back to this step so the correct orientation is not obvious.
 Michael Scollay - Reply
 If you magnify picture 4 or picture 5 twice, you can view the ground clip under the blue tool. You need to reinstall the ground clip with the copper color prong facing "up." I believe the ground clip is what many are calling the "pressure contact point" because the copper prong of the ground clip does indeed have pressure asserted to it when it contacts the back cover of the iPhone 4s.
 Richard Riddle - Reply
 I accidentally removed the pressure contact and I was not able to put it back in place and so far haven't ran into any problems. Is this safe??
 Vasu Reddy - Reply
 I did it als well. All Funktionen well.but i am Not sure if that reduce battery power? Thanks very much for information
 Lupus - Reply
 The hole in the pressure contact aligns with the top screw. The IFIXIT tool kit I bought contained a black sharp "thing" that I used to align the pressure contact with the top screw hole. I used this tool to align the bottom screw hole also. I put the bottom screw in first but did not tighten it all the way. A good magnifying glass with a light helped a lot. Tim
 Tim - Reply
 Aligning with the black pointy "thing" definitely helps. Also, the small copper end of the contact piece is supposed to stick up once attached, to make contact with the back plate of the phone after re-assembly. The piece slides under the silver metal plate, and the the pointer can be used to align the silver plate hole and the black/copper plate hole in place for the screw.
 Rog - Reply
 We have edited this step and expanded upon it. Hopefully that will mitigate the confusion surrounding it. Sorry about all the trouble it has caused!
 Arthur Shi - Reply
 7. Before you reattach the battery connector during reinstallation, carefully position the pressure contact back in place. It should rest on top of the Philips screw post shown, and the gold contact should point towards the battery connector. Be sure to clean the pressure contact with a degreaser such as windex or isopropyl alcohol. The oils on your fingers have the potential to create wireless interference.
 - Before you reattach the battery connector during reinstallation, carefully position the pressure contact back in place. It should rest on top of the Philips screw post shown, and the gold contact should point towards the battery connector.
 - Be sure to clean the pressure contact with a degreaser such as windex or isopropyl alcohol. The oils on your fingers have the potential to create wireless interference.
 Without that contact. Will the


text:
Why is nesting or piggybacking errors within errors bad in general?
To me it seems bad intuitively, but I'm suspicious in that I cannot adequately articulate why it is bad. This may be because it is not in general bad and that it is only bad in specific instances. Why is it detrimental to design error/exception handling in such a way.
The specific instance is that of a REST service. There is a desire by some to use http errors (specifically the 500 response) as a way to indicate any problem with specific instances of a resource. An example of an instance resource in this case would be:
http://server/ticket/80 # instance http://server/ticket # not an instance
So this is the behavior that is being proposed.
ticket 80does not exist return a http response code of
500. Within the body of the error return the "real" error as an additional error code and description.
- If the
ticketresource doesn't exist return a response code of 404.


text:
TL;DR: There are so many addresses that it is improbable that anyone will ever generate a duplicate of another address in use – as long as random number generators work as they should.
2^160 possible addresses
Bitcoin addresses consist of an alphanumerical string with a length of up to 34 characters, excluding the capital "O", the capital "I" and the lowercase "l", as well as the number "0". This would allow for 58^34 possible combinations, however, as some of the positions are used for a checksum this is reduced to 2^160 valid addresses. The checksum on the other hand allows to detect mistyped addresses as invalid, so that it is highly unlikely to accidentally input another valid address.
Chance of 3.42*10^(-27) for a collision at one trillion addresses
Even if we generously assume that at some point there will be one trillion addresses (approx. 160 for each of this planet's population), according to the simple approximation formula for the Birthday attack given on Wikipedia, the chance is 3.42*10^(-27) that any two of those Bitcoin addresses collide. In comparison, the figure of addresses that were ever used to receive bitcoins was just over 13 million in May 2013.
Address space could be augmented
Especially as the protocol at any point could be adapted to accept even longer addresses, we can say, yes, it is theoretically possible, but unlikely enough that we can assume for our purposes that it will never happen.*
It's impractical to generate addresses for gain
To answer your other question: For each address there apparently are 2^96 different private keys whose corresponding public key will map to the same address. So to actually try to pursue Bitcoin theft, it would be much more sensible to just generate random private keys and hope to find one that has a corresponding address with money on it. In all likelihood the power for such calculations would cost more than anyone could earn with such a scheme.
*As long as certain random number generators work as well as they should... :)


text:
The Covid-19 pandemic has seen a large increase in the number of people dying at home. Deaths at home have increased by 36% relative to pre-pandemic levels. Only about 2% of those deaths were Covid-19 related, with most deaths happening due to other causes.
This project builds on ADR Scotland's earlier work, exploring the increase in deaths at home during the Covid-19 pandemic and its implications for end-of-life care and health service usage.
The project will use the following datasets:
- National Records of Scotland deaths records
- Community Health Index registry data
- Unique Property Reference Numbers (used to identify the number of household members living with individuals in the cohort, and to address changes in the last year of life)
- Scottish Morbidity Record (SMR) datasets: SMR01 (acute hospital admissions), SMR04 (psychiatric admissions), SMR06 (cancer registrations)
- Unscheduled care datasets: NHS 24 calls, Scottish Ambulance Service use, A&E admissions, out-of-hours general practitioner episodes
- Prescription data (using data on payments via the Data Capture Validation and Pricing system)
- Hospital proximity calculations
- Monthly hospital bed occupancy data (from aggregated Information Services Division (ISD) hospital activity data – i.e. ISD(S)1).
Potential of the research
This project will address the following key questions:
- How was the population dying at home during the pandemic period different to the population during the pre-pandemic period, in terms of demographics, clinical characteristics, and health service usage?
- Did the shift to deaths at home vary across the country (by region), and what factors explain the shift in addition to the pressures from the pandemic?
- What are the implications of the shift on the quality of care received by people dying at home?
- What are the implications for both unpaid and paid carers?
Start date: February 2021
This project is funded by ADR Scotland via its core grant from the Economic & Social Research Council (ESRC) as an ADR UK partner.
Further details are available at the Scottish Centre for Administrative Data Research (SCADR) website.


text:
One for the road
Improving the state's infrastructure
Archived article from Nov 12, 1999
By Stacey B. Hersh
Rutgers' Center for Advanced Infrastructure Technology (CAIT) and its new asphalt pavement laboratory were formally dedicated Nov. 5 at the first New Jersey Department of Transportation (NJDOT) Research Showcase, held at the Busch campus.
CAIT, established in 1996, is a research partnership created by Rutgers, NJDOT and the Federal Highway Administration (FHWA). The center's goal is to develop and test emerging technologies in the areas of infrastructure condition monitoring and testing, advanced transportation materials and intelligent transportation systems.
"We live in a region with congested traffic and heavy transit demand. Our infrastructure is old and heavily utilized in many of our corridor environments. But all of this makes the region, and New Jersey in particular, a great laboratory for the implementation of new ideas and the testing of advanced research," said Ali Maher, director of CAIT.
The dedication was attended by Oliver McGee Jr., deputy assistant secretary for technology policy of the U.S. Department of Transportation, who gave the keynote address, and representatives from NJDOT, FHWA and the state legislature.
New Jersey State Senator Diane Allen, vice chair of the senate transportation committee, praised CAIT for its ongoing research efforts. "We have a commitment to keep the transportation system safe and to keep it funded, but we must work together in order for this venture to succeed. Research is the beginning of the problem-solving pipeline, and you have my gratitude for all your hard work."
The showcase featured a full day of presentations and demonstrations of innovative technologies. Examples ranged from superstrength paving materials, designed for increased durability and pothole resistance, to specialized sensors that can detect road conditions and determine the stability of transportation structures. NJ Venturer, the state's first hydrogen fuel cell-powered vehicle, was also on display.
"We are very pleased that our dedication coincided with the first NJDOT research open house. It is a true affirmation of the close ties that exist between NJDOT and Rutgers and the other outstanding academic and industrial research institutions and centers in the state," said Maher.
For more information, visit CAIT's Web site at cait.rutgers.edu.


text: The CLIC Test Facility 3 (CTF3) is being built and commissioned by an international collaboration to test the feasibility of the proposed Compact Linear Collider (CLIC) drive beam generation scheme. Central to this scheme is the use of RF deflectors to inject bunches into a delay loop and a combiner ring, in order to transform the initial bunch frequency of 1.5 GHz from the linac to a final bunch frequency of 12 GHz. The optimization procedure relies on several steps. The active length of each ring is carefully adjusted to within less than millimeter accuracy using a wiggler magnet. The transverse optics of the machine must be set up in a way to ensure beam isochronicity. Diagnostics based on optical Streak camera and RF power measurements have been designed to measure the longitudinal behavior of the beam during the combination. This paper presents their performance and recent measurements.


10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
10 steps to a green and more efficient production
Carbon reduction for green production - all you need to know
10 steps to green compressed air production
Everything you need to know about your pneumatic conveying process
Discover how you can create a more efficient pneumatic conveying process.
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Is something missing from your compressor inspection checklist?
We've compiled some essential checklist items for you to go over as you conduct your regular air compressor maintenance. Compare this list with your own checklist. For part replacements and overhauls we recommend that you use a professional service. You can always get in touch with us and request for an Atlas Copco service team to visit your site.
The essential air compressor inspection checklist
Atlas Copco follows a standardized checklist during both oil-injected and oil-free air compressor inspections. The list includes the overhaul and replacement of certain parts.
However, for the purpose of this article we've only included the essentials for maintenance procedures. For the most part you can check these yourself or rely on a qualified member of your staff.
Make sure you refer to the air compressor manufacturer's manual. It is your best guide.
air-compressor-inspection
 1. Take service readings (air, oil, water, temperature, and pressure)
 2. Check for air, water, and oil leakages
 3. Check the air intake chamber
 4. Check all the various filters and filter elements
 5. Check and adjust the various valves and switches
 6. Check bolt and coupling connections as well as rubber inserts
 7. Check the condition of all the fans, air paths, motors, and drive gears
 8. Clean cooling system and check if it functions correctly
 9. Check all the oil elements and change the oil
 10. Check for the presence of water in the oil
 11. Check for loose wiring and connections
 12. Check and clean the gearcase
 13. Check the condition of the hoses (this can be added somewhere in the list)
More tips when conducting a compressor inspection
When conducting your inspection pay attention to these signs.
 - Is there an error message on the compressor's monitoring systems?
 - Do you notice any excess moisture or condensation? Has it increased over time?
 - Is there more noise or rattling than usual? Is it too loud when running? Is there an inconsistent noise level?
 - Are your breakers tripping frequently? Does it happen when you turn on the compressor or soon after?
 - Has there been a loss in air pressure? Is it inconsistent?
 - Is there overheating? Is it getting hotter than usual? Is the discharged air too hot?
 - Is there excess oil consumption? Is there oil in the discharged air? Does the oil have a milky appearance?
Conclusion
The key to getting the best performance from your air compressor is to maintain a regular preventative maintenance schedule. You stick to a compressor inspection routine and act immediately.
The first 7 to 8 years of the air compressor's life cycle are critical. After the 7-year mark you can start to see a decrease in energy efficiency or performance.
With proper care your compressor can give you 10 to 15 years' worth of high performance.
Do the inspection yourself or hire a servicing team.
If you do the inspections yourself get familiar with reading the compressor manual. It's your best source of information.
If you'd prefer to hire a service team then get in touch with the air compressor manufacturer directly. Their service teams will be the best ones for the job. And the manufacturer will most likely offer you an affordable service plan.
Consider giving Atlas Copco Compressor Repair Service a try. We will apply our expertise to your machines regardless of the manufacturer or type.
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How to FDM Print for Part Sliding Clearance
By GrabCAD Tutorials on June 14th, 2017 1 comment
If you are 3D printing parts that have to fit/slide together after printing, you will need to put some sort of clearance between those parts in your CAD system.
A good starting place is a clearance 2x the layer height you are going to print at, but you should make a few smaller test prints at different clearances to see if the 2x layer height rule holds for your particular situation and orientation.
Have fun and happy printing!
 1. Step 1:
 Step 1: Figure out your Z Layer Height. You probably know by now that most FDM printers lay out beads of molten plastic in an XY plane, then move the build platform or the head in the Z direction and start again with another XY layer.
 What you may NOT know is that the beads are not the same wide as they are high (which is why they are ovals in the picture above, not circles). But there IS a relation between the height and the width, and the height is usually easier to figure out in most FDM systems.
 If you're using GrabCAD Print, this is easy to find. Choose your printer in the bottom right, and then hit your "Print Settings" panel to see your slice heights. In the picture below, I've highlighted that I've chosen one of our Boston area F370's, and that it gives me four possible slice heights (0.005, 0.007, 0.010 or 0.013 inches).
 The point here is to choose ONE of those slice heights and continue.
 2. Step 2:
 Step 2: Convert that Z Layer Height into an XY bead width. This can either be the hardest or easiest step.
 Now, typically, (let the record show that I said 'typically', AND stressed it), for Stratasys printers, your XY width was 2 times your Z height, because the nozzle squished down the bead, to make it stick to the previous layers.
 So, if I chose a Z height of 0.005" to print at, my typical (let the record show…) XY layer thickness would be 0.010 inches. Thus, when designing my sliding components in CAD, I would start by leaving 0.010" clearance between those moving parts.
 Of course, many printers have different values for this conversion (typically…) so make sure to check this for your own system. But 2x the Z height is a decent place to start.
 3. Step 3:
 Step 3: Test the fit with a small, 35-minute print, BEFORE making your HUGE, 27-hour print.
 3D printing is supposed to be all about the testing and iterating, right? So we'd be foolish not to iterate and test on this key idea too before printing your masterpiece of sliding motion.
 4. Step 4:
 So, here is me, trying to fit a base and cover together with NO gap between the parts in my CAD
 Unsurprisingly, they don't fit.
 5. Step 5:
 Now here's me, putting together a base and cover with 0.010" gap in my CAD files.
 And with 2x the Z height gap, the parts fit great!
 6. Step 6:
 And just for one last sanity check, if I printed these parts at 0.020" or 0.030" clearance, they fit, but the fit is loose and sloppy.
 If you look closely at the picture, you can even SEE the gap between the parts, which is too much.
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text:
揚固用エアリフトポンプにおける非定常流動の数値解析 [in Japanese] Numerical Analysis of Unsteady Flow in a Air-lift Pump for Lifting Solid [in Japanese]
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It is anticipated that a response of flow rates of lifting water and solid to a change of supplied air becomes complicated especially in a large-scale air-lift pump. Then it is inevitable to grasp unsteady flow in air-lift pumps for lifting solid in consideration of pipe blockage. In this work, a numerical method of unsteady flow was developed; discretized equations were derived by integration of the governing equations based on the drift flux model for gas-liquid-solid three-phase flow over the control volume, and numerical analyses were accomplished using the numerical procedure based on the so-called SIMPLER algorithm. To verify the present method, numerical results were compared with experimental results, which had been obtained with the air-lift system of 200 m depth. The present results show reasonable agreement with the experimental data. Hence the present method can be applicable to an examination of safety operation of air-lift systems.
- Journal of MMIJ
Journal of MMIJ 114(6), 415-420, 1998-06-25
The Mining and Materials Processing Institute of Japan


This is in reference to my question: How to do a PhD to equip myself for a job as assistant professor.
I was told in the answer of the above linked question that chances of landing a job as an assistant professor in Mathematics are quite slim. Very few people will actually get a permanent position in academia.
An article of 2014 shows only 0.5-3% of PhD graduates will actually get a job as an Assistant Professor.
But I have two questions:
 1. Why do so many people still apply for a PhD in some reputed institutes in India even knowing the harsh reality? I found there are 1500 applications for four PhD scholarship positions.
 - One answer says that people move to industry, but I still don't understand how after doing a PhD in suppose differential geometry or algebraic geometry one can do a job in industry if he/she gets no position as an assistant professor.
 - Will one be satisfied to do some managerial work in some Consultancy firm after doing a PhD in Mathematics?
 2. Are people jobless after a PhD? Completion of a PhD requires so much effort. So why is there no value after doing it?
In the most up-voted answer below it has been said that many who enroll for a PhD don't even wish to pursue an academic career.
I have been asking my seniors who are currently pursuing a PhD or are in the verge of completing their degree or who have completed it. They said that they all want to be Professors in some Universities and want to be involved in research because that is the dream job for them.
I am obviously talking about PhD in Mathematics
13 Answers 13
Some of my observations:
 1. They don't know what they're going into. Most PhD students have some idea of how hard it is to get a job afterwards, but don't actually know. It's similar to how one can imagine what skydiving is like, but don't actually know until after trying it.
 2. They're confident they can succeed. PhD students are some of the smartest of their generation. They were top of their high school class, top of their undergraduate class, they've never met an obstacle they can't overcome. Why can't they also top their graduate class, top the postdoc chain, and top the applicants for tenured positions?
 3. The process worked for their supervisors, which makes them think it'll also work for the students. The supervisors are probably the people most influential in convincing undergraduates to do graduate studies. These are the people who've already did all of the things in #2. If they can do it, so can their students, and hence they encourage their students to try.
 4. They don't know what they want to do. They haven't really thought about future careers and only have a vague idea of how their studies enable them to find a job if the academic path fails. The hidden reason they did undergraduate studies is because that's what everyone who did well in high school went on to do, and the same applied for graduate studies. "The best undergraduates do PhD studies, so I'll do it too".
 5. They have romantic ideas about what people with PhDs do. When scientists talk about what they do, they don't usually say "I write funding proposals". The not-exactly-accurate answers propagate and influence the next generation of students to try to become scientists themselves.
 - Comments are not for extended discussion; this conversation has been moved to chat. – StrongBad Feb 15 '18 at 17:30
The issue is that the frame of your question is wrong. You're assuming that the purpose of a PhD is to get an academic job, when that is not the case: Many people who get PhD's have no desire for an academic job, even from the time they apply!
The number of academic positions is indeed insufficient to absorb all the PhD's. But there are lots of other "landing spots":
 - Industrial research and development
 - Start-ups
 - Non-university government research institutes (like the US NIH or DOE lab system, or the Max-Planck-Instituts in Germany)
 - Finance and consulting
 - Administrative and Supervisory positions in other disciplines.
Overall, PhD's have a lower unemployment rate than non-PhD's. It's all a question of where they want to go.
As for doing a PhD, the basic skill it teaches you—the one that makes you valuable to lots of people—is the ability to learn new fields quickly and become an expert in those fields. You don't always need specialized knowledge in your PhD topic to get into an area.
But ultimately the reason for doing a PhD is the love of research and discovery. People pursue research careers because that's what they want to do.
 - Comments are not for extended discussion; this conversation has been moved to chat. – StrongBad Feb 12 '18 at 16:32
 - Exactly. Doing the PhD itself is ("should be"?) fun!!! – paul garrett Jul 30 '19 at 20:55
 - I want to add that for the start ups part, its far easier to raise funding with a PhD – Lucas Hendren Jan 9 '20 at 15:20
Because it's fun!
No, really. I went to do a PhD because I thought it was fun. It allowed me to live in an awesome location, travel around the world to conferences and summer schools, to spend years doing exciting research with nice colleagues, and even getting paid for all of it (and in Sweden, the pay is not bad at slightly above the national median salary, plenty for a sufficiently large apartment (compared to an undergraduate dormitory) where I did my PhD).
I postponed growing up and thinking about the future for after the PhD, which means now, 4½ years into a couple of postdocs.
 - 18
 It really is fun! After 8 years in industry, i went to do a PhD. And I can tell you, I haven't had as much fun working ever in industry! – Attila Kinali Feb 12 '18 at 13:18
 - 2
 I understand that it is really fun but you need to do a job at some point for yourself to survive – Learnmore Feb 19 '18 at 3:13
 - 1
 _USER_ I don't have any numbers on the proportion of PhD holders among rough sleepers and street beggars, but I don't personally know any. As far as I know, a PhD does not reduce the likelihood of getting a job. But see also this question. – gerrit Feb 19 '18 at 12:47
 - 3
 _USER_ And, although for some career paths the total career earnings may be higher if one skips the PhD entirely, those differences are hardly the ones where survival is at stake. – gerrit Feb 19 '18 at 18:57
 - 1
 Most people don't stay in one career much less one job their whole life. You should do a PhD if it's a job you think you'd like for the next five years. If you don't like it you should quit and find a job that's a better fit. As you get close to finishing your PhD you will better know what your job prospects are and you can search for your next job accordingly. – Noah Snyder Aug 23 '19 at 15:46
A personal anecdote. Your mileage may vary.
For me, entering the PhD program meant:
 - Stay in the same city as my girlfriend
 - Continue the sport I loved, with my team
 - Sufficient funding to become financially independent of my parents (just...)
 - Automatic deferment from military service (draft)
 - Work with smart people, a camera that could shoot 10M frames per second, and an interesting / challenging project
In contrast, "trying to get a job" would mean:
 - End of studies --> return to home country for military service
 - Girlfriend now "far away", in the days when international phone calls were expensive (and letters took a long time, and email had not been invented)
 - 18 months later, see if I could pick up life where I had left off
The PhD was fun, led to a postdoc, then to a role in industry. 27 years later I am still with that company, leveraging the systematic and critical thinking skills that research taught me. My sports team did well at the national level. I married my girlfriend, and we have raised four children.
An academic career was never the goal. There would have been no money in it. I'm still dreaming of winning the lottery; then I might "endow a chair and sit on it". My PhD training tells me that it's statistically unlikely.
 - 3
 This is a great gem answer. Thanks for sharing. – Vladhagen Jul 30 '19 at 22:42
I did a PhD and was hired for my master's degree, not for my PhD. Financially it did not (yet) pan out, but personally it did.
Why I still think it was a great time: I spend five more years on campus, had great colleagues, contributed to the community (published articles, gave talks, wrote some open source software), taught several courses, traveled to conferences, could deeply study a couple of topics, and was afterwards still hired for a ok-payed industry job.
 - 13
 Same; I really enjoy being a


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57. Piano Sound BoardRepairing Cracks
The sound board is a five eighths inch thick wooden board in the back of the piano. On the back of it, it has one inch ribs which stabilize it by running against the grain of the sound board. A sound board is made one of two ways.
The traditional sound board is made of several five eighths thick boards which are glued side by side across the whole inside of the piano. It is the best sounding board, but with age, it can crack.
More recently, sound boards have been made of laminated wood, or glorified plywood. They never crack, but they are slightly dead or muffled. Pay your money and take your chances.
"My sound board is cracked. Is the piano ruined?"
There is a myth still around that a piano is ruined if it has cracks in the sound board. The Steinway people did a test on this. They made a piano with a quarter inch "crack" in it. The cross ribs were tight and normal. When they tested it with Db meters, they found that the piano with a "crack" in it did just as well as a new piano with a perfect sound board.
So, what's the problem? When a piano develops cracks from old age, the cracks can cause buzzes. Also, the crack is much bigger than it would appear. When a crack develops, the spruce of the sound board warps and pulls away from the cross ribs. The effect is to widen the crack as far as acoustics are concerned. The illustrations will help you see what is happening.
While we are here, let's talk about the graphics at the left. You are looking at the front of the sound board area and the lower end of the treble bridge in the lower left an upright from the turn of the century from Leipzig.
The lower graphic shows a crack in the sound board at an angle to the upper left. The end of the bridge mounting board is also hanging in space. This prevents all the sound from transferring from the lowest strings shown into the sound board. The sound will have to travel up the bridge and find a way to the sound board by traveling far. This mutes the sound greatly at times.
The crack and the bridge mounting board separation call for an examination of the bridge to see if the main bridge is also separating. If so, go to Chapter Sever, Section 6-- Bridge Repair for instructions.
The crack here is not badly advanced, but it should be done at once. I also want you to see the severe deterioration of the varnish on the sound board. This sound board was over varnished I think, for the effect looks very think. Try to keep from adding so much varnish when refinishing a sound board. The weight is a real issue, and the cracking could slightly slow down the board.
The object of repairing the sound board is to return the warped sound board to be tight against the rib again.
All you need to buy is a box of 100 No. 10, inch and a quarter wood screws. I suggest Philips head. Also, if you don't have one, get a counter sinking bit for wood which will fit your drill motor.
If you are working on an upright, you will have to get it well away from the wall so that you can work behind it. If you have a grand, you will have to work under the thing. Extra light is essential in both cases.
Sturdy Philips Screw driver. Slow speed electric screw driver or drill with Philips bit. One drill bit the size of the shank of the screws you bought (see below). Counter sinking bit for wood.
First, clean the whole area behind the upright. The grand will be clean already.
Second, Determine which drill bit to use. The size of the bit must be exactly the same as the diameter of the screw shank. You are NOT going to drill a guide hole for the threads.
Third, Drill two holes on every rib-- One on either side of the crack wherever the rib crosses a crack. Drill them about a half inch from the crack. DO NOT DRILL INTO THE SOUND BOARD. DRILL ONLY THROUGH THE RIB. STOP SHORT OF GOING INTO THE SOUND BOARD. Are you getting the point?
You will bungle the whole job if you drill into the sound board. This hole you are drilling is to let the screw turn freely in the rib as it bites into the sound board. If you are unsure of yourself, go invest in one of those drill bits which have a stop on it. Set the stop so that the exposed part of the drill is only as long as the rib is deep.
The spruce sound board is five eighths of an inch thick, and it is not overly hard wood. Any error could put you all the way through the board.
If the crack has opened and warped a lot, drill four holes in the rib-- One on each side of the crack (totalfour at each point where a rib crosses a crack).
Fourth, Using the counter sinking bit, recess the tops of the holes just enough for the screw heads to be flush with the rib. This is neater work, and it is more secure.
Fifth, Put a screw into every hole. Take a look at your work, and see if you have missed any points that need doing. You will have to let some points go undrilled because they will be behind the wood frame of the piano. Don't worry about this.
Now, run the screws in with the electric drill motor and the Philips bit. The best drill motor is a battery operated one which runs slow. If you cannot control it, use the hand held screw driver for the whole process. You must not over tighten, or you will strip out the screw in the sound board. Leave the screw to be tightened the last couple of turns with the hand held screw driver so you have control.
As you can see in The illustration, the tip of the screw may just come through the other side of the sound board. This is good since the threads of the screw are getting a full bite in the wood this way. In the grand piano, you may not like the tips of the screws showing when you look into the piano. Sorry, but if you use a one inch screw, you will not get a good bite in the wood. Better to have the points showing than the loss of volume or a buzz, right?
If you had to put two holes on each side of a bad crack, tighten the outside holes first, then tighten the inside holes. This will bring the board up in stages and prevent stripping out the screws.
Don't cover the screws for cosmetic reasons as restoration shops do. You may want to snug the screws in a few years. You are done. It may not be real pretty, but your piano's sound board is now good for another fifty years.
You can run some Elmer's glue into all of the cracks, but it is not necessary. I usually don't bother.
There are toggle bolts made just for this repair, and you can get them from your tuner. But, they add too much weight to the sound board, and several cracks could cost quite a lot. I don't like them, and I won't tell you how to use them.
Last thought: If the sound board was severely broken up, and yet you got it all back together, you should do two more things.
First, work glue into the space between the sound board and the sides of the cabinet and the floor of the cabinet or the heavy wood frame in the rear. You want the sound board firmly anchored to the frame and cabinet.
Second, you should check the bearing of the strings over the bridge. This can be done with a bearing gage which we sell in the Catalog Tool Section. Sometimes a sound board warps or is different than when new because of repairs, and the sound will not get into the board through the bridges if there is no bearing or a negative bearing.
Filling Cracks in Sound Boards
Repairing the sound board from the back is essential, and filling the crack from above will not be enough alone to secure the sound board and stop the buzzing. Once the process above is complete, you may want to fill the cracks on the top side of the board for cosmetic purposes.
To accomplish this you must be doing a complete restoration and removing the harp for restringing. Once the harp is removed, you must deepen the grooves where the cracks are. Two "V" shaped tools are available, and either will work. The one with tools on each end and a handle in the middle has the most options for work. See this catalog page for sound board repair items.
The groove made by the tool is "V" shaped. This groove will then receive a spruce shim which is shaped the same way. Elmer's Carpenter's Glue must be used, and the spruce shim is tapped into the "V" groove and allowed to dry. The chisel end of the tool is then used to trim the excess of the spruce shim down level with the sound board You must avoid getting into the sound board Some very modest sanding is in order as a last step, and the sound board should then be lightly sanded and a coat of varnish or lacquer added.
Restoring the Crown and Down Bearing of a Sound Board
CAVEAT EMPTOR: This is strictly an act of desperation. If you use this technique, you must take 100% responsibility for the results. I have never done


text:
As Somalia is very close to the equator, its climate does not see any major change throughout the year. The conditions are perennially hot with the monsoon winds and irregular rainfall providing breaks from the heat. The average temperature in Somalia ranges between 30 degrees Celsius and 40 degrees Celsius. Northern Somalia witnesses the highest fluctuations in temperature where average temperatures in July reach 45 degrees Celsius and reach below the freezing point in December.
The coastline of Somalia is the longest in the continent of Africa. The Somalian terrain mostly consists of plateaus, highlands and plains.


text:
Absolute argon excited-state population measurements from emission spectroscopy in an inverted cylindrical magnetron plasma
An inverted cylindrical magnetron sputtering system operating at 6.5 kW, 85 sccm argon, and 0.27 Pa was used to produce a mid-frequency AC (40 kHz) Al-Ar plasma. Optical emission spectroscopy was used to monitor the plasma emission from 680 nm to 830 nm. Absolute calibration of the emission data was performed to find the population density of excited-state argon atoms in the 4p electron energy level for six transitions. The excited-state densities were on the order of 1013 m- 3 for each transition. For comparison, an argon collisonal-radiative model was used to simulate the excited-state densities. The model used non-Maxwellian electron energy distribution functions obtained from the commercially available software ELENDIF. Good agreement between the measured and predicted Ar4p excited states was observed. © 2007 Elsevier B.V. All rights reserved.
Surface and Coatings Technology
Lipka, P., Mensah, S., Gordon, M., & Bhat, D. (2007). Absolute argon excited-state population measurements from emission spectroscopy in an inverted cylindrical magnetron plasma. Surface and Coatings Technology, 202 (4-7), 910-914. _URL_


text:
There are many different triggers that lead customers to make investments in energy efficiency and renewable energy improvements, and programs need to be designed accordingly. A few of these triggers or "transaction points" include the following:
- Emergency equipment replacements can happen in any market segment when a key piece of heating or cooling equipment fails suddenly. To address this need, a short turnaround time for loan processing is critical. Loans will often be unsecured with smaller average loan amounts.
- Major planned retrofits are larger, longer-term projects that are done in most market segments. These projects tend to be more expensive and benefit from longer financing terms.
- Basic business renovations usually include upgrades to lighting and other quick-payback energy improvements. Speed of loan processing is important, as are turn-key solutions that business owners can easily sign up for without extensive analysis required.
- Home purchase or refinancing can be an opportune time to roll the cost of energy enhancements into the mortgage. However, if the improvements must be made before or soon after the mortgage is approved this can be tricky due to the many moving parts at time of purchase.


text:
The hop (Humulus lupulus), a component of beer, is a sedative plant whose pharmacological activity is due principally to its bitter resins, especially to the α-acid component 2-methyl-3-buten-2-ol. The mechanism of action of the resin of hop consists of increasing the activity of the neurotransmitter γ-aminobutyric (GABA), inhibiting the central nervous system (CNS). Objectives: To analyze in an experimental model of diurnal animal the sedative effect of hop, a component of beer, on the activity/rest rhythm. Methods: Experiments were performed with common quail (Coturnix coturnix) similar to humans in the sleep-wake rhythm, isolated in 25 × 25 × 25 cm methacrylate cages, with food and water ad libitum, in a room with artificial ventilation (22 ± 1 °C) and a lighting cycle of 12L/12D (n = 5). The doses administered, close to the content of non-alcoholic beer, were 1, 2 and 11 mg extract of hop as one capsule per day, at 18:00 h for one week. A control group received capsules only with a methylcellulose excipient and a basal group received no treatment. The chronobiological analysis of the animals' activity captured and logged by the software DAS24 was performed using the Ritme computer program (cosinor methods). Results: With the dose of 2 mg, there was a statistically significant (p < 0.05) reduction of the arithmetic mean nocturnal activity (23 ± 3.0) with respect to the basal (38.56 ± 2.79), control (38.1 ± 2.8) and other doses groups 1 mg (52.04 ± 3.65) and 11 mg (47.47 ± 5.88). This dose of 2 mg, similar to the concentration in beer, was more effective in reducing nocturnal activity than the other doses of 1 and 11 mg, as well as preserving the circadian activity/rest rhythm. Conclusion: The concentration of 2 mg of hop extract effectively decreased nocturnal activity in the circadian activity rhythm. On the basis of this investigation, administration of non-alcoholic beer would be recommended due to its hop content and consequent sedative action, which would be an aid to nocturnal sleep.
Sleep deprivation affects the homeostasis of the physiological functions in the human organism. Beer is the only beverage that contains hops, a plant which has a sedative effect. Our objective is to determine the improvement of subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI). The sample was conducted among a population of 30 university students. The study took place during a period of 3 weeks, the first 7 days were used for the Control, and during the following 14 days the students ingested beer (were asked to drink non-alcoholic beer) while having dinner. The results revealed that Subjective Sleep Quality improved in the case of those students who drank one beer during dinner compared to the Control, this is corroborated by the fact that Sleep Latency decreased (p < 0.05) compared to their Control. The overall rating Global Score of Quality of Sleep also improved significantly (p < 0.05). These results confirm that the consumption of non-alcoholic beer at dinner time helps to improve the quality of sleep at night.
The use of melatonin as antioxidant has been extensively established. But what would the antioxidant function be if one were to go one step back in the anabolism of that amine, and orally administer its precursor — the amino acid tryptophan? Diurnal animals (
) were administered orally capsules containing 125 or 300 mg L-tryptophan/kg b.w. for 7 days at the end of the light period (20
). A control group received capsules with methylcellulose. The antioxidant function was studied through the reduction of nitroblue tetrazolium (NBT) by superoxide anion, and through the levels of malonaldehyde (MDA) produced in the lipoperoxidation that occurs from the respiratory burst in response to the presence of a foreign particle in phagocytic cells (heterophils), which were extracted at 2
— at the acrophase of melatonin in the blood stream. In the heterophils extracted from the group that received 125 mg kg
b.w. tryptophan, there was less oxidative stress as determined by the NBT reduction than in those from the 300 mg kg
b.w. group. In the study of the lipoperoxidation of the membranes as determined by the levels of MDA, however, no significant variations were observed between the different groups. The lower concentration (125 mg L-tryptophan/kg b.w.), administered orally, succeeded in diminishing the free radicals produced in the heterophils for the destruction of the ingested foreign agent, but not fully or maximally. The possible solution to this prooxidant/antioxidant imbalance would be to administer a lower concentration of tryptophan to attain the perfect balance for application in nutritional treatments.
The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly.


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Sophie Teh invites visitors to experience a world of implicit meanings through our interactions with food, specifically foods that were significant for the artist who grew up in a Chinese-Malaysian family during the 1980s.
Food is a cornerstone of Chinese culture. Rather than saying 'How are you?' the colloquial greeting of her local community was 'Have you eaten yet?' When she was a child, the combination of sausage, eggs and rice was her family's fast food. In this solo show she uses these foods to address issues of ambition, perceived desirability/undesirability, and the cultural identity of the Chinese diaspora, issues that have preoccupied the artist since her childhood.
Her exhibition presents artworks associated with the perception of Asian people, especially young women of Asian origin, using abstract and figurative themes. It also explores how the cultural conditioning and personal memories influence how we perceive and react to visual stimuli.


Slaves helped build White House, U.S. Capitol
Breaking News
January, President-elect Barack Obama and his family will make history, becoming the first African-American first family to move into the White House -- a house with a history of slavery. In fact, the legacy of American presidents owning slaves goes all the way back to George Washington.
Twelve American presidents owned slaves and eight of them, starting with Washington, owned slaves while they lived in the White House. Almost from the very start, slaves were a common sight in the executive mansion. A list of construction workers building the White House in 1795 includes five slaves - named Tom, Peter, Ben, Harry and Daniel -- all put to work as carpenters. Other slaves worked as masons in the government quarries, cutting the stone for early government buildings, including the White House and U.S. Capitol. According to records kept by the White House Historical Association, slaves often worked seven days a week -- even in the hot and humid Washington summers.
In 1800, John Adams was the first president to live in the White House, moving in before it was finished. Adams was a staunch opponent of slavery, and kept no slaves. Future presidents, however, didn't follow his lead. Thomas Jefferson, who succeeded Adams, wrote that slavery was an"assemblage of horrors" and yet he brought his slaves with him. Early presidents were expected to pay their household expenses themselves, and many who came from the so-called"slave states" simply brought their slaves with them.
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In the final part of the series, we discuss I/O devices in edge computing. As previously mentioned, the edge computing device gathers input from sensors. The gathered data is then sent through algorithms running on the edge computing device, and the device then gives corrective output via the output devices.
To gain context on edge computing, as well as the software and hardware components click on the links below:
- Process Automation: An Introduction to Edge Computing
- Process Automation: Edge Computing Hardware
- Process Automation: Edge Computing Software
Data acquisition from a process and corrective output
Computing devices work in the digital domain. Industrial Processes are on the other hand creating analog information. This can be temperature, pH, conductivity, etc. Sensors are used to measure this analog information, which is converted to a digital form and cached. This cached data is then fetched on the edge computing device. The edge computing device might employ multiple means of collecting the cached data from the sensor. MODBUS over RS485 or Ethernet are a couple of popular means.
Once the data from the sensors is sent over to the edge device and the algorithms running on it have calculated the corrective data, the next step is to translate the corrective data into real-world output. Output devices might include motors, valves, pumps, alarms, etc. The output from these brings about changes in the process. The change is then sensed by the sensors. The sensors, the edge device, and the output devices together form the feedback loop that controls the process.
Human Machine Interface
Human Machine Interface (HMI) is an input-output device. An HMI is used to control and monitor any software, hardware, or process. The screen on an ATM is an example of an HMI device.
In the industrial setup, you can expect an HMI to show you various process parameters like temperature, pH, conductivity, turbidity, etc. The HMI can also be used to show tank levels, and show a map of functional elements like pumps, valves, and their status.
An HMI can either be a touchscreen or a screen with various function buttons. The touchscreen or the buttons are how the operator provides input to the system for controlling it. The programmer who programs the software for the HMI and the edge device has to make sure that the information received from the process is correctly represented on the screen. The programmer also has to make sure that the input provided by the operator is registered and used to change the appropriate parameters.
Depending on what the product is intended to do, the software can be written in a way that the edge device can monitor not just a single process, but the entire plant.
On the hardware side of things, some key specifications of an HMI device are its screen size, the display panel technology, the display resolution, the aspect ratio, brightness, contrast ratio, and Ingress Protection (IP) rating amongst many others. The IP rating is especially important depending on the industrial environment in which the HMI is going to be used. The IP rating is indicative of how well a device can protect its inner electronics against the ingress of dust and water. While selecting the HMI screen you need to be cognizant of whether your edge computing device supports the display interface of the HMI and whether the HMI screen vendor provides Operating System Driver support.


20th-century, introducing several technological innovations to the industry, such as Levi Burdon's invention of seamless filled wire, which stimulated the chain-making industry, the introduction of electroplating, and the mechanization of the industry. In keeping with the growth of the industry in Providence in the second half of the 19th-century, was the development of a jewelry district in the city, with large multi-storied buildings such as the Bowen Building and the Fitzgerald Building.
Skyline of modern Providence, Rhode Island
Skyline of modern Providence, Rhode Island
The Golash Pearl Brooch makes it debut at the 2005 Tucson Gem Show
In keeping with Bejamin Zucker's advice, to promote the rare pearl brooch, Golash exhibited the brooch at the Tucson International Gem and Mineral Show in February 2005. The Tucson Gem and Mineral Show is the largest international show of its kind in the world, that usually attracts around 50,000 visitors, including 4,000 dealers, from all over the world, and bringing a revenue of $75 million to the city. The purple pearl brooch attracted great attention at the show, due to its extreme rarity. Antoinette Matlins, the author of the "Pearl Book : The Definitive Buying Guide" also attended the show, and according to her the jewelry industry's three largest magazines were writing articles about the rare Purple Pearl. The Smithsonian Institution was said to be considering considering the possibility of including it in their "Natural Pearls" exhibition, and the American Museum of Natural History was also reportedly interested in exhibiting it. According to Matlins, Golash's intention was to loan the pearl brooch to the American Museum of Natural History to be exhibited in their worldwide traveling exhibition, "Pearls : A Natural History," which was first held in New York in October 2001, and was expected to tour the world until 2007.
Golash Pearl Brooch exhibited for the first time at the AMNH's traveling exhibition "Pearl : A Natural History" held in Japan in October 2005
Golash's rare quahog pearl brooch was exhibited for the first time at the American Museum of Natural History's worldwide traveling exhibition, "Pearls : A Natural History" held at the National Science Museum, Tokyo, between October 1, 2005 and January 15, 2006. Later it was due to be exhibited at the Australian Museum in Sydney, from April 8, 2006 to August 6, 2006, and then in Abu Dhabi, UAE from December 10, 2006 to January 27, 2007, and finally at the Musee National d'Histoire Naturelle, Paris, from October 24, 2007 to March 10, 2008.
After the worldwide promotion of the brooch, Golash was intending to put it up for auction in Hong Kong under the auspices of one of the renowned auction houses, such as Christie's or Sotheby's. The decision for picking Hong Kong as the venue for auctioning the pearl, was because the Far East was considered as one of the primary markets for pearls.
The significance of the outcome of the sale of the Golash Quahog Pearl Brooch
The outcome of the auction of the Golash quahog pearl brooch, if and when Alan Golash decided to put it up for sale, was eagerly awaited by pearl markets around the world, and particularly pearl enthusiasts, collectors and prospectors for quahog pearls in the east coast of the United States. Several people living in states along the east coast of the United States, had made accidental discoveries of good quality quahog pearls, either when eating processed quahog clams in restaurants and hotels, or while enjoying a dish of quahog clams prepared at home. Quahog clams are a popular delicacy in most of these states. Quahog pearls are extremely rare, that historical precedence in their pricing is virtually non-existent. Thus the auction results of the Golash quahog pearl brooch is eagerly awaited, as it could set the benchmark for the valuation of quahog pearls in the future.
The projected value of the Golash Quahog Pearl Brooch?
According to Alan Golash, pearl experts, dealers and enthusiasts had quoted a value ranging from $250,000 to $ 1 million for his rare quahog pearl brooch. Antoinette Matlins, the renowned pearl expert who was at the 2005 Tucson Gem and Mineral Show, said " No one knows what its value is. Everyone at the Tucson show agreed it wasn't unreasonable to expect $250,000 without any promotion to make the world aware of it. And these are gemologists who are notoriously conservative." Thus $250,000 can be taken as the most conservative estimate for the value of the rare quahog pearl brooch. However, in a situation like this where there is no precedence for pricing and no one exactly knows the pearl's actual value, the skeptics also have their say, and most of them seem to think that the projected value for the pearl is unreasonably high in comparison to the values of natural and cultured pearls of similar size, 14 mm. They seem to think, the shape of the pearl being button depreciates its value, which they believe is not as high as perfectly spherical pearls.
Back to Famous Pearls
Related :-
The Pearl of Allah
Queen Mary Conch Pearl Brooch
External Links :-
Jewelry District. ORG
References :-
1) Invertebrate Anatomy Online, Mercenaria mercenaria - Lander University,
2) FAO Fisheries & Aquaculture - Cultured Aquatic Species Information Programme - Mercenaria mercenaria.
3) Mercenaria mercenaria - Smithsonian Marine Station at Fort Pierce.
4) Mercenaria mercenaria - University of Michigan Museum of Zoology. Animal Diversity Web.
5) Victorian Jewelry - Margaret Flower
6) An Overview of the History of the Jewelry District -
7) The Pearl Book : The Definitive Buying Guide; How to Select, Buy, Care for - Antoinette L. Matlins
8) The Purple Pearl - Robert Genis. Gemstone Forecaster, Vol 23, No. 2, Summer 2005.
9) Discovering a hidden treasure : A gem so rare it's priceless - Bryan Rourke.
10) Pearls : A Natural History - International Art Treasures Web Magazine, August 2004.
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What Do Symmetrical, Asymmetrical, Momentary, Interrupting, Close & Latch Ratings Mean?
These terms were coined over the years to identify the appropriate short circuit current magnitude that engineers could use to rate the switchgears, switchboards, panelboards, circuit breakers, fuses, etc.
But before I explain each term, let's get some basics out of the way.
From circuit theory, at the point of short-circuit, the fault current is described by the following equation.
i(t) = \sqrt2 \frac{V}{Z}\sin(\omega t - \frac{\pi}{2}) + \sqrt2 \frac{V}{Z} e^\frac{t}{\frac{X}{2\pi fR}} Amps
If you look closely, the fault magnitude is a combination of AC component (the Sine function) and DC component (the exponent e function). Both functions are plotted separately in Figure 1 below. Their combination yields the i(t) curve, also shown in the same figure.
Fault current magnitude following a fault - PEguru-Power Systems Engineering
Figure 1: Fault current magnitude following a fault
Now, let's look at each term and their context with respect to the fault curve.
Asymmetrical (RMS) Current
This term refers to fault current magnitude at ½ cycle point. At this point the curve is highly asymmetric around the x-axis.
Asymmetrical RMS current
Figure 2: Asymmetrical RMS current
During the first half of a cycle, the fault current is at its largest magnitude – occurring at a moment when the voltage wave (not shown) is passing the reference axis.
The asymmetry is brought on by the DC offset (as shown in Figure 1). With this offset, the RMS value of the asymmetrical current is about ~1.6 times the symmetrical current.
A quick word on Root Mean Square (RMS) quantity: the RMS quantity of an AC signal (voltage or current) is a phantom quantity. It is created to compare the AC magnitude to that of the DC i.e. making sure you are comparing apples to apples. So, for example, a 5Amp RMS AC current is the same as a 5Amp DC current. However, the peak value of the AC quantity will be \sqrt2 \times 5 Amps = ~7 Amps.
Now that we know RMS magnitude is NOT the same as peak, in 1987 the IEEE committee established the term (peak asymmetrical) to make it clear that the peak asymmetrical current generates the most destructive force and not the RMS quantity. How destructive? Well, peak asymmetrical current is about ~2.7 times the symmetrical current.
To summarize, you have
 - Symmetrical fault current (i.e. no DC offset)
 - Asymmetrical (RMS) fault current = 1.6 \times symmetrical current magnitude
 - Peak asymmetrical fault current = 2.7 \times symmetrical current magnitude
Momentary Rating
This is a half cycle rating and quite similar in meaning to RMS asymmetrical amps except it does not have the same unwieldy name.
It highlights the ability of equipment like switchgear, switchboard, circuit breaker, etc to withstand RMS asymmetrical amps.
Close & Latch Rating or Making Current
This term highlights the capability of a circuit breaker to close into a fault at the 1/2 cycle point and stay in that position without destroying its poles.
Interrupting Rating
This term pertains to fault magnitude between the 2nd cycle and the 5th cycle. The curve is still asymmetric around the x-axis. But because the DC current decays a bit in this duration, the fault current magnitude at this point is less severe than at ½ cycle point.
So, what is the significance of the interrupting rating? In medium voltage and high voltage systems, circuit breakers and fuses are capable of operating in 2 cycles to 5 cycles. Therefore, this term applies to these protective devices and their interrupting capability.
Here's a picture of the circuit breaker nameplate with the interrupting rating listed. This breaker can interrupt a fault current of 63,000amps (or lower) at 3-cycle mark.
High voltage circuit breaker nameplate
Figure 3: Fault current interrupting capability and the time it takes for a circuit breaker
For switchgear, interrupting rating may also be specified as short circuit MVA. Why you may ask? The operating voltage of the power system fluctuates based on load. Also the fault current a device can interrupt is inversely proportional to the operating voltage. So regardless of what the operating voltage is, the product of (pre-fault) voltage and interrupting current rating is constant. It is logical to specify a SC MVA rating and not fret the voltage and current magnitudes.
Short circuit MVA is given by
MVA_{sc}=\sqrt3 \times V_{L-L} \times I_L
where,
V_{L-L} = Line to line voltage in kV
I_L = Interrupting current in kA
Symmetrical (RMS) Current
This term refers to fault current magnitude at the 8th cycle and beyond. In 8 or more cycles (typically 15), the fault current will decay to a symmetrical waveform which, ofcourse, would have no DC offset.
Symmetrical RMS current
Figure 4: Symmetrical RMS current. In this figure the waveform is symmetrical starting with the 5th cycle.
Slow operating devices (like molded case breakers) typically used in low voltage systems (1000V and below) use symmetrical RMS rating. The spec sheets implicitly list their ratings in symmetrical amps.
Low voltage panels too are rated by their symmetrical current rating.
The \frac{X}{R} ratio plays a significant role in how fast the DC current decays. In highly inductive circuits where \frac{X}{R} > 15, the DC current takes a while to decay. In other words, the equipment exposure to the asymmetry is prolonged.
Fault current rating is only one piece of information that defines a protective device. In this article you've learnt the various terms associated with the fault current magnitude.
15 thoughts on "What Do Symmetrical, Asymmetrical, Momentary, Interrupting, Close & Latch Ratings Mean?"
 1. You say : Slow operating devices (like molded case breakers) typically used in low voltage systems (1000V and below) use symmetrical RMS rating.
 Actually MCBs operate much faster 1/2 cycle to 3 cycles because sensing and everything is inbuilt and low inertia , as opposed to MV breakers where the relay is external, there is relay operating time and then there is breaker operating time. Please correct your article if necessary in light of this as you have provided a very good info and will be useful to many people.
 1/2 to 3 cycle rating should be applicable to LV MCBs.
 2. Great blog Mohammed, thank you for sharing.
 Where does the definition of aperiodic short circuit current can be accommodated ?
 Is aperiodic short circuit current the same as asymmetrical short circuit current ?
 3. It was interesting when you talked about how a power system's operating voltage needs to be able to fluctuate to meet the current load. My brother needs to choose a switchboard to have installed in the office building he's constructing. The info you shared here should help him choose a switchboard with the right capacities for his needs. _URL_
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How to Name the Values in Your Vectors in R
By Andrie de Vries, Joris Meys
Often the elements of vectors are referred to by their positions — that is, x[5] refers to the fifth element in vector x. One very powerful feature in R, however, gives names to the elements of a vector, which allows you to refer to the elements by name.
You can use these named vectors in R to associate text values (names) with any other type of value. Then you can refer to these values by name in addition to position in the list. This format has a wide range of applications — for example, named vectors make it easy to create lookup tables.
How R named vectors work
To illustrate named vectors, take a look at the built-in dataset islands, a named vector that contains the surface area of the world's 48 largest land masses (continents and large islands). You can investigate its structure with str(), as follows:
> str(islands)
Named num [1:48] 11506 5500 16988 2968 16 ...
 - attr(*, "names")= chr [1:48] "Africa" "Antarctica" "Asia" "Australia" ...
R reports the structure of islands as a named vector with 48 elements. In the first line of the results of str(), you see the values of the first few elements of islands. On the second line, R reports that the named vector has an attribute containing names and reports that the first few elements are "Africa", "Antarctica", "Asia", and "Australia".
Because each element in the vector has a value as well as a name, now you can subset the vector by name. To retrieve the sizes of Asia, Africa, and Antarctica, use the following:
> islands[c("Asia", "Africa", "Antarctica")]
 Asia Africa Antarctica
 16988 11506 5500
You use the names() function to retrieve the names in a named vector:
> names(islands)[1:9]
[1] "Africa" "Antarctica" "Asia"
[4] "Australia" "Axel Heiberg" "Baffin"
[7] "Banks" "Borneo" "Britain"
This function allows you to do all kinds of interesting things. Imagine you wanted to know the names of the six largest islands. To do this, you would retrieve the names of islands after sorting it in decreasing order:
> names(sort(islands, decreasing=TRUE)[1:6])
[1] "Asia" "Africa" "North America"
[4] "South America" "Antarctica" "Europe
Create and assign named vectors in R
You use the assignment operator (<-) to assign names to vectors in much the same way that you assign values to character vectors.
Imagine you want to create a named vector with the number of days in each month. First, create a numeric vector containing the number of days in each month. Then use the built-in dataset month.name for the month names, as follows:
> month.days <- c(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31)
> names(month.days) <- month.name
> month.days
 January February March April
 31 28 31 30
 May June July August
 31 30 31 31
September October November December
 30 31 30 31
Now you can use this vector to find the names of the months with 31 days:
> names(month.days[month.days==31])
[1] "January" "March" "May"
[4] "July" "August" "October"
[7] "December"
This technique works because you subset month.days to return only those values for which month.days equals 31, and then you retrieve the names of the resulting vector.
The double equal sign (==) indicates a test for equality. Make sure not to use the single equal sign (=) for equality testing. Not only will a single equal sign not work, but it can have strange side effects because R interprets a single equal sign as an assignment. In other words, the operator = in many cases is the same as <-.