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New approach for obtaining the time-evolution law of a chaotic light field in a damping gaining-process
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作者 龚黎华 周南润 +1 位作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期31-33,共3页
A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(... A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(t) is derived and the solution of f for the damping and gaining processes are studied separately. Our approach is direct and the result is concise since it is not necessary for us to know the Kraus operators in advance. 展开更多
关键词 chaotic light field damping gaining process time evolution law quantum communication
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Corn imports by China seen gaining sevenfold to record
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《China's Foreign Trade》 2012年第4期46-46,共1页
According to Bloomberg on March 18,corn imports by China,the world’s second-largest consumer,may surge sevenfold to a record 28 million metric tons by 2015-2016 as local production fails to keep pace with increased
关键词 IMPORTS gaining RECORD SURGE CONSUMER AGRICULTURAL
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China's Urbanization is Gaining Momentum
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作者 崔如春 《China Economist》 2007年第3期138-144,共7页
Alongside China’s rapid economic growth after the adoption of the reform and opening-up policy,urbanization has progressed fairly quickly. Since 1998 in particular the urbanization drive has been accelerating.What is... Alongside China’s rapid economic growth after the adoption of the reform and opening-up policy,urbanization has progressed fairly quickly. Since 1998 in particular the urbanization drive has been accelerating.What is the current status of China’s urbanization drive?In this article Cui Ruchun consults an enormous range of statistics to analyze China’s current urbanization level,urban economic development,infrastructure construction,environment construction, developments in science,technology and education,as well as the living standard of urban residents. 展开更多
关键词 THAN HIGH China’s Urbanization is gaining Momentum
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Russian Food Is Gaining Popularity among Chinese Consumers
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作者 Niki Liu 《China's Foreign Trade》 2016年第4期34-35,共2页
Russian is proactively tapping into the Chinese food market and China is importing more Russian food.According to statistics from customs,the Sino-Russian trade volume hit$64.2billion in the year of 2015,down 27.8%,an... Russian is proactively tapping into the Chinese food market and China is importing more Russian food.According to statistics from customs,the Sino-Russian trade volume hit$64.2billion in the year of 2015,down 27.8%,and Russia’s exports to China stood at$31.4 billion,down by 19.1%.'It is difficult for Russian companies to nudge into the 展开更多
关键词 Russian Food Is gaining Popularity among Chinese Consumers MORE
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China's Digital Children's Book Market is Gaining Popularity
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作者 Liu Xinwei 《China's Foreign Trade》 2016年第5期44-45,共2页
Status quo and future trends of 2015children’s publications released by the Shanghai Press and Publication shows that in the past decade,the domestic children’s book market is developing rapidly with an average annu... Status quo and future trends of 2015children’s publications released by the Shanghai Press and Publication shows that in the past decade,the domestic children’s book market is developing rapidly with an average annual growth of 10%.Children’s books are seeing an increasing ratio with a market share of over 40%. 展开更多
关键词 China’s Digital Children’s Book Market is gaining Popularity BOOK
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Domestic Oral Care Brands Are Regaining Lost Ground
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作者 Zhang Xuan 《China Detergent & Cosmetics》 2023年第1期26-28,共3页
Domestic toothpastes forced to retreat The stories of domestic toothpastes are not as good as soda water. Due to the strength of domestic drinks in recent years, soda water are regaining power. Two Cola brands made ot... Domestic toothpastes forced to retreat The stories of domestic toothpastes are not as good as soda water. Due to the strength of domestic drinks in recent years, soda water are regaining power. Two Cola brands made other drinks lose grounds in the market. Nowadays, the latest domestic drinks keep emerging and the competition in the market is getting fierce. 展开更多
关键词 BRAND gaining DRINK
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Gaining Momentum
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作者 Ni Yanshuo 《ChinAfrica》 2015年第12期20-23,共4页
AFRICA is much closer to China than people think. There is a little bit of Africa in Songzhuang, a town in suburban Beijing's Tongzhou District, where the African Art Village came up last year. The sprawling 1.3-hect... AFRICA is much closer to China than people think. There is a little bit of Africa in Songzhuang, a town in suburban Beijing's Tongzhou District, where the African Art Village came up last year. The sprawling 1.3-hectare project showcases an eclectic collection of African art - Makonde sculptures from Tanzania, copper plate etchings from Zambia, masks from Malawi, and much more. 展开更多
关键词 gaining Momentum
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Gaining From G20
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作者 Ni Yanshuo 《ChinAfrica》 2016年第9期20-21,共2页
THE upcoming G20 Summit is not just an occasion for world leaders and top entrepreneurs to come together and discuss the trends and solutions for global economic development. The residents of Mantoushan Community of S... THE upcoming G20 Summit is not just an occasion for world leaders and top entrepreneurs to come together and discuss the trends and solutions for global economic development. The residents of Mantoushan Community of Shangcheng District in Hangzhou. host city of the summit to be held on Sep- tember 4-5, have also been reaping the benefits from the summit's preparations. 展开更多
关键词 gaining From G20
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Waste Classification Gaining Momentum
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作者 YE XIAONAN ZHU RUNHUA 《China Today》 2020年第9期28-29,共2页
AFTER the revised regulation on domestic waste classification came into force in Beijing on May 1 this year,waste sorting has gained renewed public attention.In previous months,similar regulations were introduced in m... AFTER the revised regulation on domestic waste classification came into force in Beijing on May 1 this year,waste sorting has gained renewed public attention.In previous months,similar regulations were introduced in many cities across China,making the practice widespread.To help citizens adapt to and accept the new rules,local authorities have come up with creative methods to help citizens classify waste properly and understand the benefits of doing so. 展开更多
关键词 PROPERLY gained classify
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Research for Gaining Knowledge 被引量:5
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作者 菲利普.杰佛丽 刘润清 《外语教学与研究》 CSSCI 北大核心 1991年第2期44-50,80,共8页
菲利普·杰佛丽女士和刘润清同志的文章讲的是教育科研和语言学科研的重要性。 读者可以从中得到启示,开始设计在科研方法指导下的教学实验或实地调查。根据本刊12年的论文统计(见1990年第4期),我国的语言学研究和外语教学研究中,... 菲利普·杰佛丽女士和刘润清同志的文章讲的是教育科研和语言学科研的重要性。 读者可以从中得到启示,开始设计在科研方法指导下的教学实验或实地调查。根据本刊12年的论文统计(见1990年第4期),我国的语言学研究和外语教学研究中,语言理论的直接引进多于有论证、有分析、有判别的引进;语言理论的引进和论证又多于对本土语言资源的开发。在外语教学方面,印象型的、经验总结式的报告多于有数据、有分析的科学实验报告。有些实验,也是为期几个月的居多,为期两三年的居少。对所得数据,进行描写性解释的居多,进行有生命力的、有指导意义的解释居少。本刊希望今后看到更多的有严密分析的实验报告或实地调查报告。 展开更多
关键词 Research for gaining Knowledge
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Discussion of Fan et al.’s paper “Gaining effciency via weighted estimators for multivariate failure time data” 被引量:1
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作者 QU Annie & XUE Lan 1 Department of Statisties, University of Illinois at Urbana-Champaign, IL61820, USA 2 Statisties Department, The Oregon State University, Corvallis, OR 97331-4606, USA 《Science China Mathematics》 SCIE 2009年第6期1134-1136,共3页
In the analysis of correlated data, it is ideal to capture the true dependence structure to increase effciency of the estimation. However, for multivariate survival data, this is extremely
关键词 time Discussion of Fan et al s paper gaining effciency via weighted estimators for multivariate failure time data
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Like a G6-nal:transcriptional control of G-protein coupled receptors during oligodendroglial development
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作者 Tim Aberle Michael Wegner 《Neural Regeneration Research》 SCIE CAS 2025年第7期2001-2002,共2页
Multilayered control of myelination:Quick,saltatory conduction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating glia.In the central nervous system,this role is taken u... Multilayered control of myelination:Quick,saltatory conduction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating glia.In the central nervous system,this role is taken up by oligodendrocytes.Oligodendrocytes are marked by the expression of the lineage determinants Sox10 and Olig2 and arise from oligodendrocyte precursor cells(OPCs)during embryonal stages.While the majority of OPCs differentiate into mature oligodendrocytes when nearby axonal segments require myelination,a small subpopulation of OPCs persist as a progenitor pool.Therefore,the timing of myelination and maintenance of the OPC pool both need to be precisely regulated.Different transcription factors either positively or negatively affect oligodendrocyte differentiation and maintenance of the OPC pool as components of a complex gene regulatory network(reviewed in Sock and Wegner,2021).Network activity is additionally influenced by extracellular signaling molecules that bind to receptors on the oligodendroglial cell surface and activate intracellular signaling pathways.How the receptors are linked to the network is poorly understood so far,but pivotal to understanding the overall regulation of central nervous system(CNS)myelination in response to environmental cues.Relevant insights were recently gained for Gpr37(Schmidt et al.,2024),a G-protein coupled receptor(GPCR)with known relevance in differentiating oligodendrocytes(Yang et al,2016). 展开更多
关键词 gained INSULATION conduction
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785 nm semiconductor laser with shallow etched gratings
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作者 YUE Yu-xin ZOU Yong-gang +5 位作者 FAN Jie FU Xi-yao ZHANG Nai-yu SONG Ying-min HUANG Zhuo-er MA Xiao-hui 《中国光学(中英文)》 北大核心 2025年第4期931-946,共16页
A new type of 785 nm semiconductor laser device has been proposed.The thin cladding and mode expansion layer structure incorporated into the epitaxy on the p-side significantly impacts the regulation of grating etchin... A new type of 785 nm semiconductor laser device has been proposed.The thin cladding and mode expansion layer structure incorporated into the epitaxy on the p-side significantly impacts the regulation of grating etching depth.Thinning of the p-side waveguide layer makes the light field bias to the n-side cladding layer.By coordinating the confinement effect of the cladding layer,the light confinement factor on the p-side is regulated.On the other hand,the introduction of a mode expansion layer facilitates the expansion of the mode profile on the p side cladding layer.Both these factors contribute positively to reducing the grating etching depth.Compared to the reported epitaxial structures of symmetric waveguides,the new structure significantly reduces the etching depth of the grating while ensuring adequate reflection intensity and maintaining resonance.Moreover,to improve the output performance of the device,the new epitaxial structure has been optimized.Based on the traditional epitaxial structure,an energy release layer and an electron blocking layer are added to improve the electronic recombination efficiency.This improved structure has an output performance comparable to that of a symmetric waveguide,despite being able to have a smaller gain area. 展开更多
关键词 surface grating etching depth epitaxial structure recombination efficiency gain area
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Optimizing neon-based gas mixtures for two-stage amplification fast-timing Micromegas detectors
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作者 Yue Meng Xu Wang +3 位作者 Jianbei Liu Ming Shao Zhiyong Zhang Yi Zhou 《中国科学技术大学学报》 北大核心 2025年第4期59-66,58,I0002,共10页
The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process th... The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance. 展开更多
关键词 gaseous detectors MICROMEGAS timing detectors fast-timing Micromegas Monte Carlo simulation gain uniformity
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Design of a wideband non-uniform microstrip line for complex impedance matching in automotive radar frequencies
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作者 ZHANG Shuang-Gen YU Tao +2 位作者 WANG Yu-Lan CHENG Zhi-Hua YAO Jian-Quan 《红外与毫米波学报》 北大核心 2025年第2期168-176,共9页
Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for co... Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for complex impedance in automotive radar frequency range is proposed.Unlike the gradient transmission line,the wavy structure is composed of periodically semi-circular segments.By adjusting the radius of the semi-circular,the surface current is varied and concentrated on the semi-circular segments,allowing a wider tunability range of the resonant frequency.The results reveal that the bandwidth of the loaded wavy transmission line antenna improves to 9.37 GHz,which is 5.81 GHz wider than that of the loaded gradient line.The gain and the half power beam width of the loaded antenna are about 14.69 dB and 9.58°,respectively.The proposed non-uniform microstrip line scheme may open up a route for realizing wideband millimeter-wave automotive radar applications. 展开更多
关键词 millimeter wave gradient line wavy transmission line broadband high gain array antenna
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Discussion on “Gaining Effciency via Weight Estimators for Multivariate Failure Time Data” by Fan, Zhou and Chen
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作者 KUK Anthony 《Science China Mathematics》 SCIE 2009年第6期1129-1130,共2页
The survival analysis literature has always lagged behind the categorical data literature in developing methods to analyze clustered or multivariate data. While estimators based on
关键词 Discussion on gaining Effciency via Weight Estimators for Multivariate Failure Time Data Zhou and Chen by Fan
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Gain adaptive tuning method for fiber Raman amplifier based on two-stage neural networks and double weights updates
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作者 MU Kuanlin WU Yue 《Optoelectronics Letters》 2025年第5期284-289,共6页
We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training ph... We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training phase, the connection weights of the unified NN are updated again in verification phase according to error between the predicted and target gains to eliminate the inherent error of the NNs. The simulation results show that the mean of root mean square error(RMSE) and maximum error of gains are 0.131 d B and 0.281 d B, respectively. It shows that the method can realize adaptive adjustment function of FRA gain with high accuracy. 展开更多
关键词 gain adaptive tuning connection weights error predicted target gains training connection weights unified nn gain adaptive tuning method double weights updates fiber raman amplifier fra
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Too Much Sitting
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作者 Ruth Devlin 《空中英语教室(初级版.大家说英语)》 2025年第12期1-1,共1页
Do you spend manyhours oftheday sitting?When you sit,you use less energy than you do when you are active.Sittingtoo much hurts your back,and it's bad for your heart.It causesyou to gain weight and may even increas... Do you spend manyhours oftheday sitting?When you sit,you use less energy than you do when you are active.Sittingtoo much hurts your back,and it's bad for your heart.It causesyou to gain weight and may even increase your risk of cancer. 展开更多
关键词 BACK WEIGHT gain weight cancer SITTING HEART energy
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Life in the Digital Era
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《ChinAfrica》 2025年第12期60-61,共2页
The Double Take column looks at a single topic from an African and Chinese perspective.This month,we explore our gains and losses from digitalisation.
关键词 GAINS African perspective Chinese perspective LOSSES digitalisation
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