A building block for GPS

first_imgAs Harvard celebrates its 375th anniversary, the Gazette is examining key moments and developments over the University’s broad and compelling history.Next time your Global Positioning System (GPS) helps you get from point A to B without pulling out a map, thank Norman Ramsey.A professor emeritus of physics who recently died at 96, Ramsey’s work lay the foundation for the development of the atomic clock, a device that allows scientists to measure time more precisely than ever, and which is a critical component in global positioning systems (GPS).Just as a grandfather clock counts the oscillations of a pendulum to keep time, atomic clocks use the movement of atoms — which oscillate at precise frequencies — to measure time. Using the devices, a second is no longer measured as a fraction of the time it takes the Earth to revolve around the sun, but as the time it take a cesium-133 atom to oscillate 9,192,631,770 times.The advantage of such clocks is in their previously unheard of accuracy. Since every cesium-133 atom oscillates at the same frequency, clocks can be built that neither lose nor gain a second in millions of years. Such precision is critical in a number of scientific fields. Atomic clocks are used to track satellites in deep space, to test Einstein’s theory of general relativity, by astronomers seeking to use multiple radio telescopes to capture images of objects light-years away, and by geologists, who use GPS to track the movement of earthquake fault lines.Despite the apparent ubiquity, however, Ramsey’s work wasn’t initially directed toward hyperprecise measurement of time, but at probing the internal structure of molecules and atoms.When he arrived at Harvard in the late 1940s, Ramsey established a lab aimed at using magnetic resonance — a technique that involved passing a stream of molecules and atoms through rapidly alternating magnetic fields — to study their structure.Inspired by his difficulty in obtaining uniform magnetic fields, however, Ramsey began searching for ways to refine the technique. What he eventually discovered was that separating the magnetic fields, and exposing the molecules and atoms to the fields briefly as they entered and exited a chamber, vastly improved the resolution. Though Ramsey dubbed his discovery the “separated oscillatory fields method,” it has since become known as the Ramsey method, and today is still in use in labs throughout the world.Ramsey’s discovery promised new insight into the structure of the physical world, but other researchers also saw it as a possible key to creating an atomic clock.“The possibility of making an atomic clock had been suggested years earlier, but no one paid much attention to the idea,” said Daniel Kleppner, Lester Wolfe Professor of Physics Emeritus at the Massachusetts Institute of Technology, who worked with Ramsey as a student. “When Norman invented the separated oscillatory fields method, people immediately realized this method could make atomic clocks practical.”But while others devoted their attention to using the Ramsey method to develop an atomic clock, Ramsey, with help from Kleppner, turned his attention in another direction: using a maser, or microwave laser, as the basis for an atomic clock. The work led to the invention of the hydrogen maser, a device still used in a host of technological applications, including GPS timing systems and radio astronomy.“He was interested in making a better clock, and the key idea for it was the hydrogen maser,” Kleppner said. “It’s fair to say that the separated oscillatory fields method opened the way to the creation of atomic clocks, but he wanted to create a still-better clock than could be made with the beams method, and that work led to the hydrogen maser.”Though the design of the device has been refined over the years, Ramsey’s essential creation remains unchanged, Kleppner said. Many time labs actually use both types of timepieces. Cesium-133 beam clocks are extremely accurate over the long term, and hydrogen masers, which are accurate in shorter-term, measure time more precisely than ever.The impact of Ramsey’s work is ultimately incalculable, Kleppner said.“His work was the beginning, and the atomic clock has turned out to be transformative on society,” he said. “The GPS system has transformed the world so many ways that people don’t realize. It’s used to transmit information over the fiber-optic cables that make up the backbone of the Internet. It keeps trucks moving across the country in the right way. It’s used in the airline industry. Without it, life would be very different.”Incredibly, though, Ramsey’s separated oscillatory fields method work didn’t just lead to atomic clocks. The method is also one of the key discoveries that led to the development of magnetic resonance imaging (MRI) as a medical diagnostic tool, Kleppner said.“I know he took great pleasure in the fact that his early work contributed to the development of MRI,” he said. “He was focused on what seemed like basic problems, but he was confident that the research was worthwhile, and that turned out to be the case.”last_img read more

Prosecutors appeal ruling that split trials in Floyd’s death

first_imgMINNEAPOLIS (AP) — Prosecutors in Minnesota have appealed a judge’s ruling that split the trials of four Minneapolis police officers charged in George Floyd’s death and kept the first trial scheduled to start in March. Hennepin County Judge Peter Cahill ruled earlier in January that Derek Chauvin, the officer seen kneeling on Floyd’s neck last May even as he said he couldn’t breathe, would go on trial March 8. Cahill also ruled that the other three officers on the scene would be tried later. He said at the time that trying all four officers at the same time would make social distancing difficult during the coronavirus pandemic. Prosecutors appealed to the state Court of Appeals Thursday.last_img

Tie in New Zealand-South Africa rugby match, Kiwis take jibe over World Cup final boundary count rule

first_img Written By Last Updated: 27th July, 2019 16:33 IST Tie In New Zealand-South Africa Rugby Match, Kiwis Take Jibe Over World Cup Final Boundary Count Rule A second tie was witnessed at a global event in the sporting world in July, the first being the controversial cricket World Cup final at Lord’s Cricket Ground in London on July 14 and the latest being the Rugby Championship match between New Zealand’s All Blacks and South Africa’s Springboks on July 27. While the former was decided in a controversial fashion by using the boundary count rule, the latter was left to be a tie.  First Published: 27th July, 2019 15:28 IST Koushik Narayanan READ: Sourav Ganguly Vs Vinod Kambli, ‘Horses For Courses’ Vs ‘same Team Across Formats’: Internet DividedCricket World Cup horror for the Kiwis:A throw from Black Caps fielder Martin Guptill deflected off Stokes’ bat while he was diving to reach his crease to complete the second run and the ball ran off to the boundary in the dying stages of the England run chase. Stokes had attempted to complete two runs and hence the umpire awarded six runs in total after the overthrow. Many former cricketers and analysts have pointed out that England should have been awarded only five runs instead of six, a match-changing effect that would have seen the hosts go down by one run to New Zealand.  The Super Over saw a dramatic last-ball thriller as New Zealand’s James Neesham and Martin Guptill attempted to chase down the 15-run target set by England but failed to do so after being run-out off the last ball. The tie in the Super Over forced the match-winner to be decided based on the team scoring a higher number of boundaries, leading to England lifting the World Cup trophy as they had scored 24 boundaries as opposed to New Zealand’s 17 boundaries.   READ: World Cup Final Controversy: Jimmy Neesham Moves On, Begins New Zealand’s 3.9-year-countdown A second tie was witnessed at a global event in the sporting world in July, the first being the controversial cricket World Cup final at Lord’s Cricket Ground in London on July 14 and the latest being the finals of the Rugby Championship match between New Zealand’s All Blacks and South Africa’s Springboks on July 27. While the former was decided in a controversial fashion by using the boundary count rule, the latter was left to be a tie. The Rugby Clash: The All Blacks took on the Springboks in Wellington in the finals of the Rugby Championship, as three times champions New Zealand looked to maintain their winning trot against South Africa. The game went down the wire and was tied at 16 each, making the game a draw. South Africa kicked off the game after winning the toss, following which they grabbed the lead initially. The All Blacks came from behind to close up on the game and eventually tied the game as both teams settled at 16 points each. In the due course of the game, New Zealand became the first team in history to bring up 16000 Test points. The All Blacks twitter handle took a dig at the controversial cricket World Cup semi-final that saw a tie between England and New Zealand to be decided in England’s favour after the boundary count rule was used to decide the winner.Here’s the tweet from the All Blacks:   COMMENT SUBSCRIBE TO US WATCH US LIVE LIVE TV FOLLOW USlast_img read more

See all five winners Jordan Ayew has scored for Crystal Palace this season [VIDEO]

first_imgGhana’s Jordan Ayew is a certified matchwinner for Crystal Palace this season.Following his goal on Saturday against Watford, Ayew has now scored the match-winning goal for the Eagles five times this season.A week after scoring in the win over Manchester United at Old Trafford, the Ghanaian was on the scoresheet again, scoring the only goal in Crystal Palace’s 1-0 win over Aston Villa in August 2019.Take a look at the goal against Villa below:🙌 The moment we made the breakthrough…Access All Over: Aston Villa (H) ➡️ https://t.co/YEUghm8DzN#CPFC pic.twitter.com/0Ijcos0iGr— Crystal Palace F.C. (@CPFC) September 3, 2019 In October, Jordan scored the last winner for Palace against West Ham – a 2-1 win.Take a look at the goal below, as well as the wait for VAR to clear it. 🎥 Access All Over: West Ham (A)Full video 👉 https://t.co/MbRc9Y0f1o#CPFC pic.twitter.com/SeubVahjy5— Crystal Palace F.C. (@CPFC) October 9, 2019He scored another magnificent 90th-winner against the Hammers in December. The goal was nominated for the Premier League’s Goal of the Month and Goal of the Year at the London Football Awards.See the spectacular goal below:*Pretends to be shocked*Jordan Ayew’s winner vs. West Ham has been nominated for the @PremierLeague Goal of the Month!Vote now 👉 https://t.co/y3ufffuIby #CPFC pic.twitter.com/Fn9IGR7qAt— Crystal Palace F.C. (@CPFC) January 3, 2020Jordan then scored the only goal in last weekend’s 1-0 win at Brighton, a crucial goal in the battle against relegation.Watch Jordan’s goal at Brighton below:🤩 How many times have you watched this?#CPFC pic.twitter.com/jlAtFdVl98— Crystal Palace F.C. (@CPFC) March 1, 2020And on Saturday, the Black Stars forward found the net with a brilliant finish against West Ham in the first half, a goal that turned out to be the only one of the game, giving Palace their second win in as many games.Here’s the goal against Watford:Strike.#CPFC pic.twitter.com/Js45C1pBOW— Crystal Palace F.C. (@CPFC) March 7, 2020Ayew has now scored eight goals this season and 24 goals overall in the Premier League.Games Ayew has scored the winning goal in this seasonCrystal Palace 1-0 Aston VillaWest Ham 1-2 Crystal PalaceCrystal Palace 2-1 West HamBrighton 0-1 Crystal PalaceCrystal Palace 1-0 Watfordlast_img read more

Nick Young enjoys resurgence under Lakers coach Luke Walton

first_img AD Quality Auto 360p 720p 1080p Top articles1/5READ MOREUCLA alum Kenny Clark signs four-year contract extension with PackersYoung has rewarded the Lakers for keeping him by averaging 13.8 points and shooting a career-high 41.3 percent from 3-point range. A delayed flight kept Young from basking further in his latest achievement during media availability on Friday, but it’s clear he feels somewhat vindicated. Earlier this week, he largely credited the support of Lakers coach Luke Walton for his being asked to participate in NBA All-Star Weekend for the first time in his 10th NBA season.“With having a coach behind me, I don’t have to look over my shoulder or worry about coming out. That plays a major part,” said the 31-year-old Young, who grew up a Lakers fan and attended championship parades while starring at Cleveland High of Reseda and USC. “It messes up with your whole cycle when you have a coach who harps on everything you do and talks so down on you. It was tough.”Walton has resisted taking credit for Young’s resurgence.“Nick’s a really good guy; he really is. So whenever you see someone like that who has put in the time and really took advantage of his second, third chance or maybe his last chance and see him having the success he’s having …” Walton said, trailing off. “As far as being a coach, that is not what is most important. But the big part of the rewards is watching the players have success and enjoy that success.”Nonetheless, Young and his teammates offered real and imagined explanations for his comeback season. NEW ORLEANS >> In his own unique way, Lakers veteran Nick Young reflected on his resurgent season while blending in some commentary on the turmoil of the past few years.When the NBA hosts its 3-point shooting contest as part of All-Star Weekend on Saturday at Smoothie King Center, Young will become the third Lakers player to participate in the event after Byron Scott (1987, 1988) and Michael Cooper (1987). Young didn’t miss an opportunity to take a jab at the former Lakers coach, who he frequently clashed with over playing time and public criticisms.“I might pick Cooper’s brain,” Young said of his contest preparation. “But I don’t know if Byron would tell me the right thing to do.”The reason for Young’s dig is obvious. He averaged 10.4 points per game on 35 percent shooting over the previous two seasons, much of which he spent in Scott’s doghouse. Even after Scott was fired in April, many believed the Lakers would trade or waive Young before the 2016-17 season. Young used the speculation as “a lot of motivation” to train extensively during the summer hoping he could reshape his future. After praising Young for making what he called “tough shots,” second-year Lakers point guard D’Angelo Russell echoed Young’s belief that he has benefited from Walton’s offensive system that puts more emphasis on passing, floor spacing and 3-point shooting. Walton added Young “has done a good job of accepting that challenge” to become a complete player by studying film, something that does not fit Young’s “Swaggy P” persona.“They are focusing on my 3-pointers so much, so I have to figure out how to get shots off. That’s been a major key,” Young said of his film study. “You have a coach that tells me he’s going to put me on tough defensive assignments. So I have to go out there and try to prove that he’s not wrong.”Young, who is bringing his parents to New Orleans, hasn’t abandoned the goofy side of his personality, though.He joked he “almost had a divorce” with the rim over his previous shooting slumps before teammate Jordan Clarkson apparently mediated.“We had them sit down in the room and talk it out,” Clarkson said. “Nick and the rim were going through a tough time, so he and the rim came to me. I told the rim to open up.”Young jokingly called Clarkson “a rim counselor” for his therapeutic help. If Young wins the 3-point contest, he might thank Clarkson for another reason.So Young could sharpen his rhythm, timing and shooting accuracy before the 3-point contest, Clarkson moved a rack of basketballs around the court during a practice last week in New York. To become what Young considered “the best rack mover,” Clarkson joked he worked in extra push-ups with the Lakers’ training staff to prepare for his recent assignment.“I got my money on Nick with all the time he put in,” Clarkson said. “He worked hard on it.”Because of that preparation, Young said he feels “confident” he will win the 3-point contest against a field that includes Golden State’s Klay Thompson, Cleveland’s Kyrie Irving, Toronto’s Kyle Lowry, Portland’s C.J. McCollum, Charlotte’s Kemba Walker, Houston’s Eric Gordon and Dallas’ Wes Matthews.“If you were a betting man and the odds were 8-to-1 on me,” Young said, “you should bet on me.”Young is less certain about his future.The Lakers tried trading Young the past two seasons because of his ineffective play. He’s nearing the end of his contract – he has one year remaining on it if he does not opt out – so the trade speculation has resumed. Leading into Thursday’s deadline, the Lakers could look to deal the veteran, who represents one of the few assets they might be willing to part with during a rebuilding season.“It’s better when you know you’re wanted,” Young said. “I’ll be all right. We’ll see what happens. I’ve been hearing this forever. It’s either stay home or hopefully go to somebody that’s making a push to the playoffs.”For now, Young is going to push to leave his mark on All-Star Weekend.“The main thing is not to get distracted by the lights,” Young said. “It is All-Star Weekend and a lot of people there. But it’s everyday in the park.”center_img Newsroom GuidelinesNews TipsContact UsReport an Errorlast_img read more

Women’s Roller Derby back on the flat track Saturday in Rossland

first_imgSome of the teams have changed, but when the West Kootenay Women’s Flat Track Roller Derby League opens the 2013 season Saturday in  Rossland there no doubt will once again be plenty of action to go around.The Rossland Arena is the site of the first doubleheader of the season when the Castlegar’s Dam City Rollers meet Salmo’s Babes of Brutality at 5 p.m.At 7 p.m., the new and improved Rossland/Trail Roller Girls host Nelson’s KillJoys.Doors open at 4 p.m.”Will this be the bout that the Dam City Rollers finally take down their nemesis, the Babes of Brutality?” said Lori Clyde of the West Kootenay Women’s Flat Track Roller Derby League.”Or will the Babes hold back the flood gates one more time?” The West Kootenay Women’s Flat Track Roller Derby League consists of five teams this season, down a few from 2012.Along with Castlegar’s Dam City Rollers, Salmo’s Babes of Brutality, Nelson Killjoys and the new Rossland/Trail Roller Girls is the Slocan’s Valley Vendettas.The league plays a host of doubleheaders throughout the summer before the season concludes with the championship bout.Roller derby is a contact sport played by two teams of five members roller skating in the same direction around a track. Game play consists of a series of short matchups (“jams”) in which both teams designate a scoring player (the “jammer”) who scores points by lapping members of the opposing team.The teams attempt to assist their own jammer whilst hindering the opposing jammer — in effect, playing both offense and defense simultaneously.West Kootenay Roller Derby is made up of 5 house teams and 1 Travel team; Castlegar’s Dam City Rollers, Salmo’s Babes of Brutality, Slocan’s Valley Vendettas, the Nelson Killjoys and Rossland Trail Roller Girls. The WKWFTRDL travel team is the Kootenay Kannibelles which is made up of a stellar bunch of athletes from all the house teams who recently placed fourth in  the National tournament held in March in Edmonton. The Kannibelles will be representing the league again this year in the western finals in Fernie in July.last_img read more

Warriors and Clippers are laying the groundwork for another great rivalry

first_imgOAKLAND — Rivalries make sports great, but at the professional level, they seem to be increasingly fleeting.Sure, every game is competition, but most contests feel like arranged play dates. Few carry actual friction. Most teams spend more time chirping at the referees than at their opponents.But the Warriors and Clippers had a real rivalry. They were the best of enemies.There was a collective loathing between the two California teams — a showdown of contrasting egos and styles that permeated …last_img

The Army’s Net Zero Energy Mission

first_imgOn August 1, the U.S. Army public affairs office in Hawaii published a feature story about the service’s new conservation initiative, which is aimed at preserving natural resources and making energy efficiency key to strategies for housing construction and improvements in transportation and general operations.“One thing that I admire about the Army is that we are full of extremely creative individuals,” Katherine Hammack, assistant secretary of the Army for installations, energy and environment, told the press officer at U.S. Army Garrison-Hawaii last month.In many cases, the Army will rely on the ingenuity and know-how of its soldiers to develop and deploy conservation strategies, although some of the more complex and large-scale energy saving initiatives will involve military and civilian experts. Among the most high-profile of these will be the U.S. Military Academy at West Point “Net Zero Installation” project – a series of facility upgrades that will include the installation of renewable-energy systems, advanced lighting and power monitoring systems, barracks upgrades, a biomass system, and the construction of a new barracks to net-zero-energy performance standards.An airtightness requirementArmy standards for airtightness, as adopted a few years ago by the U.S. Army Corps of Engineers, are already very high for both renovations and new construction. The Army Corps’ HVAC commissioning procedures include air-barrier testing that show building envelope leakage rates of no more than 0.25 cubic feet per minute per square foot of building envelope, when tested at 75 Pascals. This is no small challenge. As noted in “Controlling Air Leakage in Tall Buildings,” an article published in 2009 by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, the Army is getting a lot of practice at identifying potential air-barrier deficiencies in building shells at the “pre-design” stage of a project, which allows the design-build team to address the issues and meet the leakage-rate requirement in a timely and cost-effective way.The need is thereIt won’t be cheap, but it is a good time to act because many of the barracks at the fortress-like academy are overcrowded, and the campus, perched high above the west bank of the Hudson River, near Highland Falls, New York, is exposed to extreme weather during the winter. Construction of the new barracks – the first built on the campus since 1972 – is scheduled to begin in 2013, and will cost about $131 million.Initial investment in West Point’s barracks project is coming from energy-saving specialist Noresco, which so far has awarded the school $25 million in Energy Savings Performance Contracts (ESPCs) – partnerships between energy service companies and federal agencies. Supervised through the Department of Energy’s Federal Energy Management Program, the partnerships allow energy service companies such as Noresco to conduct comprehensive energy audits for a federal facility, identify improvements to save energy, design and construct a project that meets the agency’s needs, and arrange the necessary funding.One advantage to ESPCs, the DOE notes, is that they allow federal agencies to move forward on energy saving projects without committing large amounts of their own capital upfront, and without special congressional appropriations. The energy service company’s obligations are extensive, however, since it must guarantee that the improvements will generate enough energy cost savings to pay for the project over the term of the partnership contract. Contract terms up to 25 years are allowed, and additional cost savings after the contract ends accrue to the federal agency.last_img read more

Awareness campaign to stop road accidents

first_imgKolkata: Shuttl, a technology-enabled, seat-based, demand-adaptive bus mobility solution on Tuesday announced the implementation ‘Safe Drive, Save Life’, a road safety awareness programme in Hooghly and Kolkata in association with Uttarpara Kotrung Municipal Corporation.’Safe Drive, Save Life’, campaign a brain child of the Chief Minister Mamata Banerjee was started by the state government to reduce the road accidents in the state. Prabir Ghosal, Member Legislative Assembly from Konnagar launched the campaign by flagging off Shuttl’s three new buses at Uttarpara. These buses will ply in the Uttarpara Kotrung Municipality region. Also Read – Bengal family worships Muslim girl as Goddess Durga in Kumari PujaSince its launch in 2015, Shuttl has made people reduce their dependence on cars and use bus-based shared mobility instead. In 2017, it launched the SAFE (Safe Anxiety Free Experience) project which provides multiple safety checks to every commuter through various embedded technology features. The company has seen rapid adoption as 57% of its commuters earlier used car for their daily commute switched over to bus. Shuttl has come up to directly address the dual challenge of congestion and pollution. Also Read – Bengal civic volunteer dies in road mishap on national highwayThe company was founded by two IITians- Amit Singh, Co-founder and CEO and Deepanshu Malviyia, Cofounder. With an aim to spread awareness about the increasing road accidents, Shuttl will extend this campaign to other regions and will organize the event in Hooghly on 26th August 2019 and in Kolkata on 27th August 2019. Shuttl has also tied up with various civic authorities and traffic police in Kolkata for this program to educate citizens and drivers on road safety, traffic rules, and driver-pedestrian best practices over the period. Speaking on the occasion, Dilip Yadav, Chairman, Uttarpara Kotrung Municipal Corporation said: “The rising number of road accidents is an issue which municipal corporation takes very seriously. By raising awareness amongst the users of roads, we aim to ensure that the roads of our city are safe and comfortable for every citizen. We are happy to partner with Shuttl in helping us spread the message of safe driving.”last_img read more