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High-efficiency unidirectional wavefront manipulation for broadband airborne sound with a planar dev
[期刊论文] 作者：Yang Tan,Bin Liang,Jianchun Cheng,
来源：中国物理B（英文版） 年份：2022
In the past decade,one-way manipulation of sound has attracted rapidly growing attention with application potentials in a plethora of scenarios ranging from ultrasound imaging to noise control.Here we propose a design of a planar device cap......
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
The COVID-19 pandemic, lasting for about two years, has undeniably pre-sented one of the greatest protracted challenges to humanity. Now it is surging with more variants that spread even faster. It has exerted a profound impact on a world d......
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
The year 2021 brought nu-merous developments in international and regional arenas, from the COVID-19 world-wide spread and climate change, to the hasty withdrawal of the U.S. from Afghanistan and the renewed atten-tion to the Nuclear Non-Pr......
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
The world has been placed on high alert by the escalation of the Russia-Ukraine crisis. The logic behind Russia\'s actions is to protect its national security and to counteract NATO attempts, led by the U.S., to press itself forward onto Ru......
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
With the Olympic flame dancing to the drums of the Chinese Year of the Tiger, the Beijing 2022 Games—the first-ever Winter Olympics held in China and its second Olympics after hosting the 2008 Summer Games—concluded on February 20, to be ......
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
The Ukraine crisis is holding “a sword of Damocles”over the global economy,UN Secretary General António Guterres has warned, especially over poor, developing countries that face skyrocketing food, fuel and fertilizer prices, and are now ......
[期刊论文] 作者：Hai-Yang Cheng,
来源：科学通报（英文版） 年份：2022
For ground-state singly charmed baryons,the Λ+c,Ξ+c and Ξ0c form an antitriplet representation and they all decay weakly.TheΩ0c,Ξ1+c,Ξ1+c and ∑++,+,0c form a sextet representation;among them,only Ω0c decays weakly....
[期刊论文] 作者：Zhong Cheng,
来源：北京周报（英文版） 年份：2022
In the ongoing Russia-Ukraine conflict,warplanes, rockets, missiles and artillery units are not the only weapons in use. An information war is proving no less fierce than the fighting taking place on the ground....
[期刊论文] 作者：Hui-Ming Cheng,
来源：国家科学评论（英文版） 年份：2022
Voids are an essential scientific issue when it comes to traditional composite materials,because they greatly de-grade the latter\'s properties and usually cause catastrophic failure [1].Many characterization methods,such as mi-croscale X-r......
[期刊论文] 作者：Jianchun Cheng,
来源：中国科学：物理学 力学 天文学（英文版） 年份：2022
Ultrasonic waves,although not audible,naturally exist at high frequencies.Ultrasound can be controlled and unitized in various scenarios.Well-known examples are bats and dolphins,which produce ultrasound and detect the reflected signal for ......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
\'We shall promote the spirit of the Olympic Movement and meet the common challenges facing the international community through solidarity,\" Chinese President Xi Jinping said in his toast at the banquet welcoming distinguished internationa......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
Prince William recently found himself in hot water following his allegedly “tone-deaf” and “racist” comments about the ongoing conflict in Ukraine during a visit to a Ukrainian cultural center in London. Social media exploded in controv......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
When Russia announced it would be blocking access to social media platforms like Twitter and Facebook, many across the West were left dismayed and criticized Russia for its “veto” on freedom of speech. Ironically, over the past years, tho......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
As the Washington National Cathedral tolled its funeral bell 900 times at 5 p.m. onFebruary 7 to recognize the 900,000 deaths from COVID-19 registered in the U.S., American elites appeared more concerned about China\'s zero-spread policy....
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
If we say the First Gulf War, from August 1990 to February 1991, was the firstever live-broadcast military conflict in the television era, then the Russian-Ukrainian conflict in February can be considered the first mass combat scene of the ......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
Private prisons in the United States have long been the topic of controversy, for example over their role in housing undocumented immigrants and asylum seekers at the U.S.-Mexico border. Several states have banned them, some banks have vowe......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
One month after the Russia-Ukraine conflict erupted in full force, U.S. President Joe Biden flew to Europe to call on American allies to impose tougher sanctions against Russia. During a meeting of NATO leaders in Brussels, Belgium, Biden o......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
In the last two days of March, New Delhi almost simultaneously hosted Russian Foreign Minister Sergey Lavrov, British Foreign Secretary Elizabeth Truss and U.S. Deputy National Security Advisor Daleep Singh. Earlier, on March 25, Chinese St......
[期刊论文] 作者：Liang Xiao,
来源：北京周报（英文版） 年份：2022
April 7, news flash: Nancy Pelosi,Speaker of the United States House of Representatives and second in line for the presidency, said Taiwan would be added to her Asian journey destinations....
Machine learning and numerical investigation on drag reduction of underwater serial multi-projectile
[期刊论文] 作者：Xi Huang,Cheng Cheng,Xiao-bing Zhang,
来源：防务技术 年份：2022
To increase launching frequency and decrease drag force of underwater projectiles,a serial multi-projectiles structure based on the principle of supercavitation is proposed in this paper.The drag reduction and supercavitation characteristic......
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