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Why Isn't There a Nobel Prize for Mathematics?

Nobel prizes are awarded as per the will of Alfred Nobel. You can read Alfred Nobel's will at Full text of Alfred Nobel's WillRead the part of will related to Nobel prize (and see the highlighted part which mentions prize category):

The whole of my remaining realizable estate shall be dealt with in the following way: the capital, invested in safe securities by my executors, shall constitute a fund, the interest on which shall be annually distributed in the form of prizes to those who, during the preceding year, shall have conferred the greatest benefit to mankind. The said interest shall be divided into five equal parts, which shall be apportioned as follows: one part to the person who shall have made the most important discovery or invention within the field of physics; one part to the person who shall have made the most important chemical discovery or improvement; one part to the person who shall have made the most important discovery within the domain of physiology or medicine; one part to the person who shall have produced in the field of literature the most outstanding work in an ideal direction; and one part to the person who shall have done the most or the best work for fraternity between nations, for the abolition or reduction of standing armies and for the holding and promotion of peace congresses. The prizes for physics and chemistry shall be awarded by the Swedish Academy of Sciences; that for physiological or medical work by the Caroline Institute in Stockholm; that for literature by the Academy in Stockholm, and that for champions of peace by a committee of five persons to be elected by the Norwegian Storting. It is my express wish that in awarding the prizes no consideration whatever shall be given to the nationality of the candidates, but that the most worthy shall receive the prize, whether he be a Scandinavian or not.Categories are Physics, Chemistry, Medicine, Literature and Peace. Economics is added later. It does not mention mathematics.

• Related Questions

Should I prepare for the IAS?

I wrote down prelims this year only and that too after preparing dedicatedly for about 10 months. I left well paying MNC job to prepare for this prestigious exam. If you are a serious aspirant, i can bet that you will surely learn a lot about almost every aspect of different subjects. It is really an awesome journey to go for. Now coming to the bitter face of this exam. Since CSAT became a qualifying exam, clearing prelims based on just G.

k paper is not at all an easy task. If you have seen previous year questions and compare them with this year paper, you will realize how unpredictable paper has become. This year UPSC has totally skipped World Geography and Art and culture sections(which usually covers around 15 questions) . It happened for the first time. The number of questions from Polity, Modern history and Indian Geography have been drastically reduced along with their typical kind which is again an unprecedented thing to do. In short it was not at all a "Balanced Paper". A sincere candidate prepares all sections and expect to score in all of them but this paper was made for those who have prepared selectively by ignoring Geography, history and focused only on current affairs. So if you think UPSC cares about you and your preparation strategy, it's clearly not the case. They simply don't give a shit to aspirants and their future. By this exam, they clearly dictated that now onwards exam will not test the complete knowledge(about all the subjects) but it will depend on your sheer luck. If you are lucky, then questions from your section will pop up in the exam. I don't know what UPSC thinks of taking such a stock of candidates into the system and i would really appreciate if someone can explain this to me. Finally my advice to you and all the future candidates is to think seriously before resigning/quitting your job and start preparing for this exam. It is far better and wise if you first clear the prelims and then take leave for preparing mains. People may have different views and opinions but the way i have analyzed this is also right

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What is the difference between raja yoga, hatha yoga and kriya yoga?

Yoga, basically, is the union of mind, body, spirit - the oneness. The practice that helps one to attain yoga is like various paths that all lead to same destination. The sage Patanjali defined the path to yoga as Raja Yoga - the penultimate how-to in the Yogasutras - explaining the discipline of working on personal and social rules of conduct that lead to asana practice, pranayama - to more subtler practices that eventually lead to moksha & kaivalya.

In other words, starting with working on the mind first.This, as we all know is very easy - not. And it was just the case with the ancestral yogis and the Hatha yoga path was derived - a system of yoga which understood that it would be much easier to work on the body and get it to listen to you (or control it) instead of spending frustrating time getting the mind to succumb to oneu2019s human attempt at control.The Hatha way is to move from gross to subtle aspects of the body and inevitably, an earnest practitioner, would realise that yamas and niyamas that are crucial to the Raja yoga path, even though they are not enforced as a preparatory step of Hatha, are all intertwined at every step. One key differentiator of Hatha Yoga is the preparatory phase of working with the body (the foremost gross element) - and that includes not just asana but also shatkarmas - cleansing practices that prep the body, the temple, as the foundation for deeper work.Eventually, all the limbs of Patanjaliu2019s ashtanga yoga integrate themselves in Hatha yoga too - and the practitioner is on his way towards Raja Yoga.Kriya yoga is another path of a yogiu2019s personal choice of journey. In this, discipline towards a practice is more an internal series of dedicated service and actions - unquestioned actions - initially externally driven but serving a deeper cleansing process to tone and strengthen the mind along with external practices and body work - both through service karma / seva and asana/ pranayama/ shatkarma.They are all interlinked, and intertwined - different paths, different combinations - but all intended to take the practitioner to the same destination. At the end, the practitioner will pick the path that is most resonant with their personal and soul driven choice.

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What fiction books should everyone read?

One novel that I would highly recommend anyone to read is Strong Medicine by Arthur Hailey.The novel is an intriguing story about human relations and personal ambitions set within the backdrop of the pharmaceutical industry.It is the story of Celia and Andrew Jordan,two strong individuals who are inexplicably drawn towards each another by a common thread:a hospitalized patient suffering from a disease which has no cure in sight.

Andrew Jordan is a medical doctor who is treating the patient,while Celia is a medical representative with a pharmaceutical manufacturer called Felding Roth.Celia gives Andrew a medication for his dying patient,which is undergoing clinical trials.Jordans patient gets cured miraculously.A bond is forged between Andrew Jordan and Celia, which culminates in marriage.

The novel then traces Celias meteoric rise and her growing ambitions to escalate the corporate hierarchy,aided by her benevolent boss,Sam Hawthorne.She is promoted as a medical trainer for the companys sales force and later as head of the organizations OTC(over-the-counter) sales division.Further elevations see her heading international research projects in England and France.

Along the way,Celia discovers the various difficulties involved in successfully operating a pharmaceutical company.What makes the story a compelling read is Celias character.She is portrayed as a hard-hitting and ambitious woman,who will leave no stone unturned to achieve success in her professional life.

However,she is a woman with very strong convictions and an equally strong conscience.Her strong values do not allow her to agree to anything illegal or hazardous with respect to health safety standards in the field of pharmaceutical research or large scale production of medications.She is a woman who stands by her convictions,no matter what.

This results in her having to resign from her company over reservations she harbours about a drug her company manufactures which she feels does not meet proper health and safety standards.Such characters are very hard to come by,either in novels,or in real life. It is indeed very difficult to find characters with such strong convictions and self-believe,who swear by the profession they practice.

Stong Medicine chronicles the story of strong and determined characters like Celia who work in industries which are fraught with lots of ups and downs.I thoroughly enjoyed reading the novel.Hope you too do

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How can you forgive yourself for mistakes of the past?

I don't know you. I don't know what you did, and I don't know why you need to forgive yourself. I can only speak from my own perspective.Forgiving yourself for letting someone else down is extremely hard. It's something I've only learnt how to do recently, but I still struggle with it.If I hurt a friend, I ask for their forgiveness. Eventually, they may, or may not forgive me, but typically I am able to move on from it. I know I have done my best, and I know I have done everything I can to seek forgiveness.A good friend once told me that you cannot ask forgiveness for yourself, the person who you are asking has no obligation to forgive you. If your issue is that you are seeking forgiveness in order to forgive yourself you will never receive it.

Remembering that helps me, but each time is very difficult and it's a process. Don't give up!However If you need to forgive yourself for letting yourself down, that's much more difficult. If I'm being completely honest, it's not something I have an answer to, either.

I wish I could give you a simple solution, but I don't have one. The feeling of letting yourself down is worse than any feeling of letting someone else down. The only way I cope with it on a day to day basis is attempting to continue bettering myself.

I remind myself that every mistake I make, is an opportunity to improve and grow as a person. I try to reflect on my actions, my behaviours, and how I react to things. I try to do this often. It doesn't always work.Regardless, I continue to try. The only way you can learn to forgive yourself, is by eventually realising that you are human. You will make mistakes. You will make them today, tomorrow, and for the rest of your life.Forgiveness is when you understand this. When you know it, and you believe it. Continue working on it. You will get there one day.We all will

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End of Halogen Light Bulbs Spells Brighter and Cleaner Future
End of Halogen Light Bulbs Spells Brighter and Cleaner Future
Halogen light bulbs will be banned from September 2021 with fluorescent light bulbs to follow, cutting emissions and saving consumers on their energy bills. ●Halogen light bulbs to be banned from this September – with fluorescent light bulbs to follow suit ●shift to LED bulbs will cut 1.26 million tonnes of CO2 – the equivalent of removing over half a million cars from UK roads ●new rules part of tighter energy efficiency standards for electrical appliances as the UK builds back greener, helping save British consumers £75 a year on their energy bills The government has announced plans today (Wednesday 9 June) to end the sale of halogen light bulbs from this September, as part of the UK’s wider efforts to tackle climate change. Legislation being brought forward this month will also include the removal of fluorescent lights from shelves from September 2023. Currently, around 2 thirds of bulbs sold in Britain are LED lights, making a considerable impact in improving the energy efficiency of the country’s buildings. They last 5 times longer than traditional halogen lightbulbs and produce the same amount of light – but use up to 80% less power. The UK began phasing out the sale of higher-energy halogen lightbulbs in 2018. The new legislation would mean retailers will no longer be able to sell the majority of halogen bulbs for general household use in the UK from 1 September. To help people make the switch, ministers are also announcing that all light bulbs will start to feature new energy efficiency advice via ‘rescaled’ energy labels on their boxes. The labels will simplify the way energy efficiency is displayed on a new scale from A-G, doing away with the A+, A++ or A+++ ratings. The new labels will raise the bar for each class, meaning very few bulbs will now be classified as A, helping consumers choose the most environmentally friendly bulbs. This measure is expected to mean that LED light bulbs will account for 85% of all bulbs sold by 2030. In addition, the government also plans to start phasing out the sale of high-energy fluorescent lightbulbs, with a view to bringing an end to their sale from September 2023. Taken together, these new rules will mark a significant shift to more energy efficient and longer lasting LEDs and will stop 1.26 million tonnes of carbon being emitted every year - the equivalent of removing over half a million cars from the UK’s roads. The move is part of a package of energy efficiency improvements to electrical appliances, which will save consumers an average of £75 a year on energy bills. Energy Minister, Anne-Marie Trevelyan, said: We’re phasing out old inefficient halogen bulbs for good, so we can move more quickly to longer lasting LED bulbs, meaning less waste and a brighter and cleaner future for the UK. By helping ensure electrical appliances use less energy but perform just as well, we’re saving households money on their bills and helping tackle climate change. Today’s plans also include a ban from September on the sale of lighting fixtures with fixed bulbs that can’t be replaced – meaning the fixtures have to be thrown away. Fixtures such as these account for 100,000 tonnes of electrical waste every year – out of a total 1.5 million tonnes of electrical waste each year. Minister for Climate Change, Lord Martin Callanan, said: Flicking the off-switch on energy inefficient light bulbs is a simple way that households can save money at the same time as saving the planet. Phasing out halogen bulbs in favour of LED alternatives that last longer, are just as bright and cheaper to run, is another way that we are helping tackle climate change. Chief Executive of Signify UK, which owns Philips lighting, Stephen Rouatt, said: We welcome the UK government’s next step in the transition towards more sustainable lighting products. Using energy-efficient LED equivalents for halogen and fluorescent lighting on an even broader scale will significantly help the UK on its journey to decarbonisation, as well as lowering the annual electricity bills for consumers. Overall, the government’s package of energy efficiency improvements will also cut 8 million tonnes of carbon emissions in 2021 by reducing the amount of energy products consume over their life-time – the equivalent of removing all emissions from Birmingham and Leeds each year.
2021 09 27
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Bright Idea: New LEDs Can Detect Off Food And Lethal Gases
Bright Idea: New LEDs Can Detect Off Food And Lethal Gases
New LED technology has potential to benefit firefighters, miners, the military, plumbers and households.(Source:University of Melbourne) Your smart device could soon be even smarter with a new infrared light emitting diode (LED) that is ‘tuneable’ to different wavelengths of light – it could enable your fridge to tell you when your food is going off and your phone to tell you if that Gucci purse is real. The technology has been developed by the University of Melbourne, the Lawrence Berkeley National Laboratory, the University of California, Berkeley, and the Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems (TMOS). They have come up with a device that could identify a suite of gases, potentially including lethal ones, improving the safety of firefighters, miners, the military, and your local plumber. The work appeared in the journal, Nature. Infrared (IR) spectrometers are common laboratory equipment that can identify different materials by analysing their infrared signatures, which is invisible to the human eye. Just like an AM radio can be tuned to different frequencies of radio wave, IR spectrometers can be tuned to different wavelengths, giving a broad-spectrum analysis of a gas sample. However, these machines are bulky and expensive and not usually practical to take out of the laboratory and into the field. “Our new technology bonds a thin layer of black phosphorus crystals to a flexible, plastic-like substrate, allowing it to be bent in ways that cause the black phosphorus to emit light of different wavelengths essentially creating a tuneable infrared LED that allows for the detection of multiple materials,” University of Melbourne Professor Kenneth Crozier said. “This technology could fit inside smartphones and become part of everyday use.”For example, the bacteria found in meat release various gases as they multiply. The presence of these gases is a good indication that the meat is spoiling and is no longer fit for consumption.“The device placed inside a fridge could send a notification that meat is going off. When pointed at a handbag, it could reveal whether the bag is made of real leather or a cheaper substitute,” said Professor Crozier, who is also the Deputy Director of TMOS.Current materials that are used for IR photodetectors and light emitting devices can be difficult to manufacture, in large part due to the need for multiple layers of perfectly linked crystals. This new black phosphorus technology requires just one layer allowing the device to be flexible, giving it unique properties when bent.“The shift in black phosphorus' emission wavelength with bending is really quite dramatic, enabling the LED to be tuned across the mid-infrared,” said Professor Ali Javey, from the University of California at Berkeley, whose group led the work.Importantly, the device could make the work of firefighters, miners and military safer, allowing them to identify potentially lethal gases from safe distances as the ultra-thin, ultra-light devices can be placed on small drones. Flying such a drone over a building fire could tell firefighters what dangers they face and equipment they’ll need.The low-cost technology could also make its way into devices for use by plumbers and building managers.“Our IR photo detectors could be integrated into a camera so that we could look at our phone screen and ‘see’ gas leaks or emissions and be able to determine what kind of gas it is,” Professor Crozier said.
2021 09 27
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Gallium Oxide White LED Prospects
Gallium Oxide White LED Prospects
Saga University in Japan has reported work towards white light-emitting diodes (WLEDs) based on rare-earth (RE)-doped gallium oxide (Ga2O3) [Yafei Huang et al, Appl. Phys. Lett., v119, p062107, 2021]. The researchers adopted a vertical integration strategy with Ga2O3 layers doped with thulium (Tm), europium (Eu) and erbium (Er) grown on top of each other. The team comments that “films grown by lateral integration are deposited side-by-side, while the co-doping of multiple rare earth elements into the same host will unavoidably degrade the crystal quality and, thus, induce undesirable threshold voltage and luminous efficiency.” The vertical strategy leads to more compact devices without compromising crystal quality. The team adds: “On the other hand, compared with phosphor-assisted WLEDs, direct white light emissions are achieved from single-material-based LEDs in this work without using additional red, blue or green phosphors, which can greatly reduce the energy re-absorption effect between different phosphors.” Such energy re-absorption would naturally impact power efficiency. The researchers also see the phosphor-free approach based on single-material-based WLEDs with direct primary color mixing as more conducive to displays based on smaller-pixel micro-LEDs. Although rare-earth doping has been tried in gallium nitride and zinc oxide devices, there are problems such as needing high voltages (~100V) or poor color balance due to spectral gaps. The Saga team sees β-Ga2O3 as “an ideal host for rare-earth ions benefiting from its ultrawide bandgap (4.9eV), which is advantageous to improve the thermal stability and luminous ability of rare-earth dopants at room temperature”. According to the researchers, at present, “there are no reports available related to full-color (white) LEDs based on rare-earth-doped Ga2O3.” The doped Ga2O3 layers were deposited on p-type gallium arsenide, p-GaAs (111), using alternate-target pulsed laser deposition (PLD) at 500°C. The Ga2O3 targets were variously doped with rare-earth oxides: 1wt.% Tm2O3, 1wt.% Eu2O3 and 5wt.% Er2O3. The laser light came from a krypton fluoride (KrF) excimer laser emitting deep-ultraviolet light at 248nm wavelength. The PLD was carried out in an oxygen atmosphere at 0.1Pa pressure. The samples consisted of 150-periods of the sequence of the three types of Ga2O3 doping (Figure 1). The growth process lasted 150 minutes. Material analysis suggested that the atomic concentrations for the doped layers were 0.3% Tm, 0.5% Eu and 2.3% Er. Figure 1: Schematic structure of LED-A based on Ga2O3:(Tm+Eu+Er)/GaAs heterojunction. The LEDs featured an indium tin oxide (ITO) transparent conductor n-electrode and gold (Au) p-electrode. The ITO was applied with direct-current sputtering; the gold with electon-beam evaporation. Atomic force microscopy showed a sample surface “filled with uniformly distributed grain-like structures” with a root-mean-square roughness of 10nm. When subjected to a forward voltage of more than 8.8V, the current begins to increase rapidly. The researchers also note that the electroluminescence (EL) is only observed under forward bias, suggesting that “simultaneously injected electrons and holes are indispensable for the EL”. The researchers associate the emitted light with 4f transitions from the Eu3+, Er3+, and Tm3+ ions (Figure 2). Figure 2: (a) Current-voltage characteristics curve of LED-A. Inset: semi-log characteristics and digital photograph of LED-A at 70mA. (b) EL spectra under different operating currents. (c) EL intensities of emissions at 475, 529, and 615nm as function of injection current. (d) CIE chromaticity coordinates under different currents.   The various peaks associated with the different ions were: 461 and 475nm with Tm3+; 529, 550, and 656nm with Er3+; 590, 615, and 712nm with Eu3+. Although the emissions somewhat overlap, the Tm ones are mainly in the blue range, Er green, and Eu red. The combination gives white light. The researchers explain: “Due to the existence of oxygen vacancy defects in the film, the simultaneous red, green, and blue emissions are supposed to be triggered by the defect-assisted energy transfer from the Ga2O3 host to RE3+ (Eu3+, Er3+, and Tm3+) ions.” On the basis of previous reports, the researchers expect the emission to be relatively independent of the temperature environment since the complete outer 5s and 5p orbitals shield the 4f shell from such influence. The positions of the peaks were found to vary little with changing current injection. However, the strength of the emissions did vary, with the balance shifting from red to green and blue as the current increases. The color content of the main device reported, LED-A, shifted from pink to white with injections from 40mA to 80mA. The correlated color temperature (CCT) varied from 2370K to 7592K, respectively, a shift from a warm to cold tone. The team reports: “For instance, the emitted light at 55mA locates at a warm-white point with CIE coordinates of (0.3739, 0.3410) and CCT of 3926K, which meets the requirements for indoor lighting applications.” The researchers also see 65mA as providing “superior” CIE coordinates, (0.3329, 0.3335), but 5479K CCT, suitable for indoor/outdoor cold-white illumination. Table 1: Thicknesses of doped Ga2O3 layers. The color balance was also varied in hardware, with the researchers producing four other device structures with different layer thicknesses of the various components (Table 1). These resulted in different color balance behavior (Figure 3). Figure 3: CIE chromaticity diagrams for (a) LED-a, (b) LED-b, (c) LED-c, and (d) LED-d under different operating currents.     The author Mike Cooke is a freelance technology journalist who has worked in the semiconductor and advanced technology sectors since 1997.  
2021 09 27
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Retailers Employing NICHIA LED Technology Are Ahead Of The Game
Retailers Employing NICHIA LED Technology Are Ahead Of The Game
After completing a successful pilot project, German retailer EDEKA equips its latest store entirely with NICHIA technology Tokushima, Japan – 3 August 2021: LED manufacturer NICHIA is a technology leader in highly efficient human centric lighting and the replication of natural light. Its innovative LED technologies are increasingly being used in retail to push the shopping experience to the next level. The most recent project is an EDEKA store in Wiesbaden-Sonnenberg, Germany, which opened its doors in May and is equipped with a lighting solution entirely based on NICHIA technology. The owners of the store engaged Prof. Dipl.-Phys. Werner Lorke and his interdisciplinary team of experts to plan and implement the project. As part of his consulting work with iO Interdisziplinäre Objekte, the physicist focuses on product and exhibition design and brings together the fields of architecture, technology, and art. He was tasked with developing and employing a lighting concept that presents the store’s merchandise in the best possible way and creates a positive shopping experience for the customer. To do this, he selected NICHIA's ‘Light so Good' technologies, which significantly enhance the quality of light: 2-in-1 tunable white, Optisolis, and Vitasolis.For the Wiesbaden-Sonnenberg project, Lorke drew, among other things, on the experience he had already gained over several years with another EDEKA branch in Wiesbaden. Above average sales figures in this store prove that the influence of light on people is enormous. Thus, lighting generally represents a great opportunity for retailers. "We are proud to say that all our activities here, in terms of introducing new illumination, have more than paid for themselves within a few months," he emphasizes. "Based on this experience, our advice to retailers, in general, is to look at lighting as a sales tool rather than as an expense."In the confectionery department, for example, a solution with adjustable color temperature has proven successful. Thanks to 2-in-1 tunable white LED and COB, it is possible to create good contrast between the merchandise on display and the aisles, as well as to install dynamic lighting in which the color temperature changes throughout the day. Optisolis products are ideal for illuminating goods such as fruit and vegetables. They can be used to produce a light spectrum that comes closest to that of the sun, while at the same time UV emission is essentially non-existent. As a result, it has a positive effect on perishable goods while fruit and vegetables shine in the best possible light. Vitasolis provides brilliant white light and a wide wavelength spectrum for pleasant illumination. A strong cyan component compared to other products has a positive effect on the human circadian rhythm. Aisles illuminated with Vitasolis in combination with Optisolis product provide shoppers with an image that is inspiring and very pleasant – a solution ideally suited, for example, in the dairy section. High CRI Optisolis illuminating the dairy products presents the merchandise more naturally while the natural white light coming from Vitasolis is suitable for illuminating the aisle. Lorke applies Vitasolis for two reasons: one, it allows for a good contrast between space and merchandise thanks to its broad spectrum and low contents of yellow spectrum. Two, its quality of light is extremely easy on the eye. As such, the technology also perfectly meets the needs of any counter areas. Here, the comfortable lighting makes waiting times more pleasant for visitors. A total of around 500 luminaires from all three 'Light so Good' technologies have been installed at EDEKA in Wiesbaden-Sonnenberg."Ultimately, each product group in the store requires its own lighting concept," states Lorke. "The secret lies in the optimal mix of color temperature, color spectrum, and contrast. At the moment, I don't see any alternative on the market to NICHIA products for achieving such a high quality of light as we have managed to create here."Note: Vitasolis and Optisolis are trademarks owned by NICHIA.
2021 09 27
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Scientists Develop Efficient GaN-based Green LEDs
Scientists Develop Efficient GaN-based Green LEDs
A research team led by Shengjun Zhou at Wuhan University has reported developing efficient GaN-based green LEDs on sapphire substrate. They proposed a hybrid nucleation layer consisting of sputtered AlN and mid-temperature GaN components to boost quantum efficiency of GaN-based green LEDs.The team says the hybrid nucleation layer provides a promising approach for the pursuit of efficient III-nitride emitters in the green-to-amber region.Currently, the development of efficient III-nitride emitters in the full visible range is very attractive. The integration of multicolour III-nitride emitters can enable efficient and precise management of the mixing spectra to realize high-resolution displays and various smart lighting applications. However, owing to the poor efficiency of III-nitride emitters in the green-to-amber region, these promising applications have been largely delayed.The researchers have fabricated high-efficiency InGaN/GaN green LEDs on sapphire substrate by using the novel hybrid nucleation layer. A stacking fault band structure was generated at the interface of hybrid nucleation layer and GaN, which facilitated the misfit stress compensation. Benefiting from the early misfit stress relaxation, they achieved reduced dislocation density and residual stress in the green LEDs. An efficiency improvement of ~16 percent was demonstrated in the mass production by using the hybrid nucleation layer. This gain is attributed to the increased localisation depth and spatial overlapping of the electron and hole wave functions.‘Toward efficient long-wavelength III-nitride emitters using a hybrid nucleation layer' by Bin Tang et al, Optics Express, 29(17), 2021 WHU team boost quantum efficiency using hybrid nucleation layer
2021 09 27
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Candidates For Next-gen LED-based Datacoms
Candidates For Next-gen LED-based Datacoms
UK researchers show how organic semiconductors, CQDs and perovskites can be used in LED-based optical communications systems A new paper from the University of Surrey and the University of Cambridge has detailed how two relatively unexplored semiconducting materials can satisfy the telecommunication industry's hunger for enormous amounts of data at ever-greater speeds.LED-based communications techniques allow computing devices, including mobile phones, to communicate with one another by using infrared light. However, LED techniques are underused because in its current state LED transmits data at far slower speeds than other wireless technologies such as light-fidelity (Li-Fi).In a paper published by Nature Electronics, the researchers from Surrey and Cambridge, along with partners from the University of Electronic Science and Technology of China, examine how organic semiconductors, colloidal quantum dots (CQDs) and metal halide perovskites (perovskites), can be used in LED-based optical communications systems.The research team explored efforts to improve the performance and efficiency of these LEDs, and they considered their potential applications in on-chip interconnects and Li-Fi.Aobo Ren, the co-first author and visiting postdoctoral researcher at the University of Surrey, said:“There's excitement surrounding CQDs and perovskites because they offer great promise for low-power, cost-effective and scalable communications modules.“Although the conventional inorganic thin-film technologies are likely to continue to play a dominant role in optical communications, we believe that LEDs based on these materials can play a complementary role that could have a sizeable impact on the industry.”Hao Wang, the co-first author and PhD student at the University of Cambridge, said: “Future applications of LEDs will not be limited to the fields of lighting and displays. The development of LEDs based on these solution-processable materials for optical communication purposes has only begun, and their performance is still far from what's required. It is necessary and timely to discuss the potential strategies and present technical challenges for the deployment of real-world communication links using these LEDs from the material, device and system aspects.”Jiang Wu, the corresponding author from the University of Electronic Science and Technology of China, said: “Photonic devices for the Internet of Things (IoT) and 6G communication systems need to be high-speed, low-cost and easy to integrate. Organic semiconductors, CQDs and perovskites are promising materials that could be used to complement and/or compete with conventional inorganic counterparts in particular optoelectronic applications.”Wei Zhang, the corresponding author and Senior Lecturer from the University of Surrey, said: “IoT and 6G communication systems represent a trillion-dollar market in the next few years. We are proud to collaborate with the top research teams in this field and accelerate the development of emerging data communication technology for rapid entry to the market in the next decade.”'Emerging light-emitting diodes for next-generation data communications' by Aobo Ren et al; Nature Electronics 2021
2021 09 27
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Seoul Semiconductor 's Innovative WICOP LED Technology
Seoul Semiconductor 's Innovative WICOP LED Technology
Seoul Semiconductor Seeks Greater Market Share in Global High-Power LED Market Valued at USD 2 Billion with Innovative WICOP LED Technology. ANSAN, South Korea--Seoul Semiconductor Co., Ltd. (KOSDAQ 046890), a leading global innovator of LED products and technology, announced that it has introduced high-power LED package ‘Z5M4’ with WICOP technology, one of the second-generation technologies in the LED industry. Z5M4 is 10% brighter than the conventional products and is easy to replace the existing high-power products. Accordingly, Seoul Semiconductor seeks to expand its market share in the USD 2 billion worth of global high-power LED market for street lighting, bay-lighting, and horticulture lighting, which has been formed by vertical chip manufacturers.   Comparison of WICOP and product design stolen under the name of COB or CSP * Vertical chip: Excellent heat dissipation structure with vertical electrodes design * COB (Chip on Board): A structure that reduces the volume by connecting wires to a semiconductor chip directly mounted on a printed circuit board * CSP (Chip Scale Package): Silicon semiconductor technology that makes BGA (Ball Grid Array) on silicon semiconductor chips and assembles them in a clean room Z5M4 LED with WICOP technology is designed to be 1:1 compatible easily with existing high-power products, and its excellent heat dissipation structure makes it a high-power LED package suitable for high-brightness and high-efficiency. It offers an industry-leading high luminous efficiency of 175 lm/W and can be used for up to 100,000 hours. Seoul Semiconductor has been leading the global market with its core patented technology, which obtained a permanent injunction against Philips TV product and 13 automotive lighting brand LED products infringing WICOP patents in 2019 and 2021.“Seoul Semiconductor’s Z5M4 LED for high-power lighting will quickly encroach the USD 2 billion market dominated by vertical technology companies. We plan to apply this product not only to the high-power lightings, but also to the  electronic device flash and automotive lightings, followed by SunLike LED, a natural sunlight spectrum LED technology,” said an official of Seoul Semiconductor. Seoul Semiconductor’s Z5M4 package with WICOP technology About Seoul Semiconductor Seoul Semiconductor is the world’s second-largest global LED manufacturer, a ranking excluding the captive market, and has more than 10,000 patents. Based on a differentiated product portfolio, Seoul offers a wide range of technologies, and mass produces innovative LED products for indoor and outdoor lighting, automotive, IT products, such as mobile phones, computer displays, and other applications, as well as the UV area. The company’s world’s first development and mass production products are becoming the LED industry standard and leading the global market with a package-free LED, WICOP; a high-voltage AC-driven LED, Acrich; an LED with 10X the output of a conventional LED, nPola; a cutting edge ultraviolet clean technology LED, Violeds; an all direction light emitting technology, filament LED; a natural sun spectrum LED, SunLike; and more.
2021 09 27
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Question with LED and Zener Diode?
Question with LED and Zener Diode?
Get a zener diode 3.5 volts higher than the one you now have1. LED Gloving Slow Shutter Speed?This is an example of rear curtain sync. Set camera to rear curtain sync Camera on tripod Low ISO Small aperture Dark conditions, the only light you want to record is the light from the gloves and the final flash. Flash mounted on camera Shutter on 'B' setting Remoter shutter release. Method. Open shutter and lock open. Move the gloves around. Close shutter. Just before the shutter closes the flash will fire, recording the face etc. Rear curtain is good because the light trails are behind the movement which is opposite to the normal flash sync. Chris2. Will the Germany led European Union be a Fourth Reich?Is EU under German domination becoming a 4 rth Reich?A supranational union is a type of multinational political union where negotiated power is delegated to an authority by governments of member states. The concept of supranational union is sometimes used to describe the European Union (EU), as a new type of political entity. (wikipedia).Germany currently is maintaining a balance of trust and power, and has no interest to get more power at the expense of trust. And of course we have interests, economical interest3. What is the brightest LED lantern?Brightest Led Lantern4. Powering an LED with transistor in saturation mode"Please do not tell me to buy other transistors" ...that's what I wanted to suggest: Use a MOSFET instead of a NPN, rated at 150 mA (or more). The gate/base of a MOSFET draws less (usualy much less) than 1 mA. Otherwise the darlington pair is another solution if for some valid reason you have to keep these specific transistors. Your calculation about R2 is correct5. what kind of LED bulb do i need for these tail lights?do no longer forget water. I particularly have 13 geckos. My abode geckos drink water i've got sprayed into the tank off the glass and flowers and my leopard geckos drink water from a bowl. My geckos purely consume crickets and different small bugs. considering they only consume at night I feed them at night. attempt conserving slightly carrot or a wedge of an orange interior the tank for any crickets that are not getting eaten perfect away so the crickets do no longer nibble on the geckos. additionally, an undertank heater on one section is significant. reptiles choose their tanks to have a heat section and a cooler section. they choose a mild on one portion of the tank additionally. Blacklights paintings nicely for my nocturnal reptiles6. the beatles vs. led zeppelin????john lennon jimmy page paul mccartney (unless we are going on bass skills alone) john bonham sgt peppers led zeppelin 2 the white album rubber soul led zeppelin a day in the life kashmir whole lotta love helter skelter black bird over the hills and far away well, after splitting the answers almost exactly 50-50 i am just as undecided as when i started. i like both for mostly different reasons.7. How to toggle LED on button press?At the moment, you've got two main problems. Firstly, both your if statements are being triggered one after the other. This is because the first if statement sets x to 0, which is part of the condition the second if statement looks for. The second problem is that you are not monitoring the previous state of the button. buttonState will appear HIGH every time round loop, even if the button has been held down for several seconds. The result is that the output pin will be quickly getting turned on and off all the time. What you need to do is store the last known state of the button. On every iteration of the main loop, only respond to the button if it's currently HIGH, and if it was LOW last time round the loop. You also need to make sure your two if statements are mutually exclusive; i. e. if you trigger one then do not trigger the other by mistake too, or it will cancel it out.Something like this should work better:As noted elsewhere, you still need to debounce the button, otherwise you are likely to get some false-positives. That can be done in hardware or software. A really simple way to get around it temporarily is to put in a delay of several milliseconds every time you detect the button changing state. It's not perfect, but it might be enough to get you started
2021 08 24
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