The car has a sleek, aerodynamic look—the back wheels are covered and mirrors on the doors are digital cameras instead of the wind grabbing old-school variety—the body is also tapered. The XL1 is the latest entry by VW to make vehicles it calls 1-liter cars—those that consume just one liter of fuel when traveling 100 kilometers. The XL1 is considered a limited edition vehicle that VW is making to test demand. To achieve such high efficiency, VW has followed three main ideas: making cars that are light, aerodynamic and that have a low center of gravity. To that end, the car is made light (it weighs just 1,753 pounds) by using carbon fiber polymers, magnesium, ceramics and aluminum in its various parts. It’s small as well, measuring just 153.1 inches in length, and 65.6 inches across and 45.5 inches from ground to roof.VW has given operators several options when driving the vehicle—it can be run as an all-electric, all-gasoline, or as a hybrid. It can also be set to run in electric mode for cruising then jump to gas mode automatically if more power is needed for sudden acceleration. The XL1, despite its name, is actually the third generation of a line of 1-liter vehicles from VW—the first was so thin driver and passenger had to sit in tandem. The XL1 is the first such vehicle from VW to be made for sale to consumers, though initially, only a lucky 250. That’s all the company is going to make unless there is added demand. VW has not yet announced when the car will be made for sale in the U.S. or how much it will cost. Citation: Volkswagen XL1: ‘World’s most efficient car’ makes its US debut (2013, October 7) retrieved 18 August 2019 from https://phys.org/news/2013-10-volkswagen-xl1-world-efficient-car.html Volkswagen will debut XL1 hybrid at March auto show (Phys.org) —VW’s XL1 hybrid car made its official debut in the United States this past week at this year’s Annual Society of Environmental Journalists conference in Chattanooga Tennessee—home of one of VW’s hi-tech manufacturing plants. The vehicle has been dubbed by various media outlets as the “world’s most efficient car.” Testing has shown the vehicle to have a fuel consumption rate of 261mpg European-200mpg US. VW reports that the car is able to travel 32 miles when driven in all-electric mode. © 2013 Phys.org Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
© 2015 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Traumatic head injuries have been in the news a lot of late, primarily because of later life lingering impacts being reported by athletes—but it is also common with soldiers and victims of car accidents. Scientists would like to better understand what happens to people who survive such events later on in life because it might lead to more effective treatments early on. To learn more, the research trio examined the skulls of men whose remains had been dug out of medieval cemeteries in Denmark. They found a surprisingly high rate of cranial vault fractures—8.9 percent of all those studied—which suggested that life back then for such men was particularly violent. The team then compared the lifespan of those with such injuries with those without them and found that traumatic head injuries that were severe enough to leave evidence of fractured skulls, meant the men were 6.2 percent more likely to die at any point later on, a likelihood that is roughly twice as high as for people with such injuries that are treated with modern methods.What is still not clear (because they were not able to determine the cause of death) is whether the medieval men died early as a direct result of their injuries, whether it was because of changed behavior due to the injury (as has been seen with many athletes) or because those with such injuries tended to live a more risky existence in general, which might have led to their initial injury and which would seem to have increased the likelihood of more injuries or even death later on. Citation: Analysis of skull fractures in medieval Denmark reveals increased risk of death later on in life (2015, January 27) retrieved 18 August 2019 from https://phys.org/news/2015-01-analysis-skull-fractures-medieval-denmark.html A healed depressed fracture on a skull from the early modern Sortebrødre cemetery in Odense, Denmark. Credit: George R. Milner; collection, ADBOU University of Southern Denmark Study could lead to better treatment for child brain injuries (Phys.org)—A trio of researchers with members from Denmark, the U.S. and Germany has found that a group of men living in medieval Denmark who had healed head traumas had a 6.2 percent higher chance of dying at any given time than did other men in the general populace. In their paper published in Proceedings of the National Academy of Sciences, Jesper Boldsen, George Milner and Svenja Weise describe their study of skulls found in medieval cemeteries and how it relates to the modern study of traumatic head injuries. Explore further Journal information: Proceedings of the National Academy of Sciences More information: Cranial vault trauma and selective mortality in medieval to early modern Denmark , Jesper L. Boldsen, PNAS, DOI: 10.1073/pnas.1412511112AbstractTo date, no estimates of the long-term effect of cranial vault fractures on the risk of dying have been generated from historical or prehistoric skeletons. Excess mortality provides a perspective on the efficacy of modern treatment, as well as the human cost of cranial injuries largely related to interpersonal violence in past populations. Three medieval to early modern Danish skeletal samples are used to estimate the effect of selective mortality on males with cranial vault injuries who survived long enough for bones to heal. The risk of dying for these men was 6.2 times higher than it was for their uninjured counterparts, estimated through a simulation study based on skeletal observations. That is about twice the increased risk of dying experienced by modern people with traumatic brain injuries. The mortality data indicate the initial trauma was probably often accompanied by brain injury. Although the latter cannot be directly observed in skeletal remains, it can be inferred through the relative risks of dying. The ability to identify the effects of selective mortality in this skeletal sample indicates it must be taken into account in paleopathological research. The problem is analogous to extrapolating from death register data to modern communities, so epidemiological studies based on mortality data have the same inherent possibility of biases as analyses of ancient skeletons.
Citation: Training neural belief-propagation decoders for quantum error-correcting codes (2019, June 4) retrieved 18 August 2019 from https://phys.org/news/2019-06-neural-belief-propagation-decoders-quantum-error-correcting.html Two researchers at Université de Sherbrooke, in Canada, have recently developed and trained neural belief-propagation (BP) decoders for quantum low-density parity-check (LDPC) codes. Their study, outlined in a paper published in Physical Review Letters, suggests that training can enhance the performance of BP decoders significantly, helping to solve issues that are commonly associated with their application in quantum research. “Ten years ago, I wrote an article with Yeojin Chung explaining how standard decoding algorithms for LDPC codes, which are broadly used in classical communication, would fail in the quantum setting,” David Poulin, one of the researchers who carried out the study, told Phys.org. “This problem has been obsessing me ever since. Recently, people have started to investigate the use of neural networks to decode quantum codes, but they all focused on a problem (decoding topological codes) that already had a number of good human-designed solutions. This was the perfect occasion to revisit my favorite open problem and use neural networks to decode quantum codes that had no previously known decoder.” While BP decoders are commonly applied in a variety of settings, so far they have proved to be unsuitable for decoding quantum error-correcting codes. This is due to a unique quantum feature referred to as ‘error degeneracy,” which essentially means that there are multiple ways to correct an error in quantum settings. Classical BP algorithms consist of of three simple equations. The structure of these equations enables an exact mapping to a feed-forward neural network. In other words, it is possible to reinterpret the BP equations commonly used to decode LDPC codes as describing the initial setting of a neural network. Past research has found that this ‘initial neural network’ does not work well in quantum settings, despite achieving better performance than random neural networks. In their study, Poulin and his colleague Ye-Hua Liu enhanced the performance of the ‘initial neural network’ by training it with data generated by numerical simulations. “The training is guided by a target function that takes into account quantum effects,” Liu told Phys.org. “Generally speaking, neural decoders have the advantage that they are adaptive to arbitrary noise statistics in realistic channels. In addition to that, our method is applicable to quantum LDPC codes without regular lattice structures. These codes are very promising for realizing low-overhead quantum error correction.”The researchers found that training the neural BP decoders using the technique they adopted improved their performance, for all the families of LDPC codes they tested. Moreover, the training technique they used could help to solve the degeneracy problem that generally plagues the decoding of quantum LDPC codes. “Training the neural BP network can significantly improve its performance for quantum error correction, which means a classical algorithm can be adapted to the quantum setting by deep-learning methods,” Liu said. “This inspires us to look for other examples like this in quantum physics, to reveal a broader connection between deep learning and natural science. For instance, belief propagation is widely used in many other research areas, including statistical physics, which implies neural BP might also benefit research in quantum statistical physics.”In their future work, Poulin and Liu plan to study neural BP in the context of statistical physics. If trained using the same technique, the researchers expect that BP, which is also referred to as the ‘cavity method’ in this particular setting, will show an improved performance in this context too. “More broadly, belief propagation belongs to the important class of message-passing algorithms, which turns out to be closely related to graph convolutional networks in deep-learning research,” Liu added. “It would be very fruitful to gain insights into these structures from a physicist’s point of view.” This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Kolkata: Responding to the Mamata Banerjee government’s request for forces, four states have finally responded and around 18 companies are expected to reach Bengal, which will be a major security boost for the upcoming Panchayat polls.”10 companies from Andhra Pradesh, 4 companies from Sikkim, 2 from Telangana and 2 from Odisha are expected to reach by Saturday,” said a senior official of Nabanna, the state secretariat.A detailed discussion on the issue of force deployment was held at the office of the State Election Commission (SEC) on Friday, that was attended by the Director General of Police Surajit Kar Purakayastha, ADG law and order Anuj Sharma and state Home secretary Atri Bhattacharya. Also Read – Heavy rain hits traffic, flightsPurakayastha has been learnt to have assured the commission of providing more forces, while the State Election Commissioner A K Singh has emphasised on proper deployment of civic volunteers.According to the final security arrangement that has been prepared by the state government, there would be a total of 71,500 armed police personnel and 80,000 civic volunteers, along with 1,800 personnel from other states for the 47,451 polling booths and other election related tasks. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedAmong the armed police personnel, there are 500 inspectors, 10,000 sub-inspectors and 61,000 constables or home guards of National Voluntary Force, armed with lathis.Kolkata Police will mobilise 9,000 police personnel to maintain security in and around the districts. These personnel would mostly be deployed in East Burdwan, Hooghly (Rural), Howrah (Rural), Sundarbans, Baruipur and 65 booths and 39 premises under the Kolkata Leather Complex (KLC) police station of the city police. Supratim Sarkar, Additional Commissioner (III) of Kolkata Police, said among these, 7,000 constables including home guards, along with 1,500 additional sub-inspectors and five sub-inspectors will be on duty on the day of polling. Sources in the SEC said that every booth will be manned by one armed personnel and one lathi wielding constable. As per data available with the commission, 30,176 single booth premises will have one armed personnel and one constable, 11,000 two booth premises will have two armed personnel and two constables, while 1,000 three booth premises will have three armed personnel and three constables. The scale will subsequently increase for 300 four booth premises, 105 five booth premises, 12 six booth premises and 17 more than six booth premises across the state.The distribution centres will include one armed officer, two armed constables and 16 civic volunteers, while the strongrooms will have two armed officers and eight armed constables. This apart, special attention will also be given to the 11 percent sensitive and very sensitive booths. The campaigning for the polls would end by 5 pm on Saturday.
Kolkata: The estranged wife of city mayor Sovan Chatterjee was today detained following his complaint that she was trying to barge into the flat where he has been staying for the last six months, the police said. Claiming that the mayor has been delaying signing papers for their daughters study abroad, his wife Ratna Chatterjee held a night-long demonstration in front of the flat in south Kolkatas Golpark area where he was staying, they said.”We have received a complaint from the mayor on the basis of which we have detained her. We are talking to her, they said.The mayor and his wife have been fighting a battle for divorce.
Kolkata: Jadavpur University (JU) has presently kept in abeyance the admission process of the Journalism & Mass Communication course (MA) after the students raised strong objections over the fee structure of the course. The course was introduced last year and the students are now in the second year of their MA course.”We had introduced self-financing PG course in Journalism and Mass Communication last year. However, students pursuing the course have raised objections over the fee structure. Also Read – Heavy rain hits traffic, flightsWe have formed a committee to examine their demands and until there is a decision on this, we have kept in abeyance the admission process,” pro vice-chancellor, JU Pradip Ghosh said.It may be mentioned that the total fees for the two year MA course is Rs 60,000 (Rs 30,000 each year), which the students claim is much higher in comparison to other universities that run a similar course. The 37 odd students, who are presently pursuing the course, have demanded that the course fees should be similar to that of regular Arts courses that run in the university. The fees for these courses according to the students is Rs 1,235 per year. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killed”We have had no internships. There has been only a handful of seminars. The infrastructure is not up to the mark. The library that we have remain closed most of the time and we face a lot of difficulty in accessing books,” Sohanu Ghosh, a student said adding that they will submit a fresh deputation to the university authorities along with their demands soon. A student pointed out that the other universities like Calcutta University, Rabindra Bharati University and Viswa Bharati University offer the same course but charge much less fees. “They have much better infrastructure in comparison to JU,” a student said. “We will urge the authorities to present a clear cut picture for charging such an exorbitant fees even when the infrastructure is lacking,” a student alleged.The students, who had sought admission in the two year course, have secured 50 percent marks in graduation and then cracked an entrance test.
If you are young and at times experience sudden weakness, perspiration, shortness of breath and the need to sit down —with your