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Evolution of Slow Dual Steady-State Optical Solitons in a Cold Three-State Medium

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Chinese Physics Letters 2012年第7期29卷 142-145页

作者： SUN jian-Qiang LI hao-chen GU Xiao-Yan Department of Mathematics College of Information Science and TechnologyHainan UniversityHaikou 570228 Department of Physics East China University of Science and TechnologyShanghai 200237

The generalized nonlinear Schr(o)dinger equation,which describes the evolution of dual steady-state optical solitons in a cold three-state medium,is written as the Hamiltonian symplectic *** symplectic method is applied to investigate evolution of dual steady-state optical *** adjusting the initial pulses,the saturation parameter variables and the distances of optical solitons,the different behaviors of dual steady-state optical solitons are analyzed.

关键词： structure solitons symplectic

Fast algorithms for determining the linear complexities of sequences over GF(p^(m)）with the period 3n

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Science China Mathematics 2006年第5期49卷 715-720页

作者： chen hao Department of Computing and Information Technology Fudan University Shanghai 200433 China

In this paper, for the the primes p such that 3 is a divisor of p - 1, we prove a result which reduces the computation of the linear complexity of a sequence over GF(pm)(any positive integer m) with the period 3n (n and pm - 1 are coprime) to the computation of the linear complexities of three sequences with the period n. Combined with some known algorithms such as generalized Games-Chan algorithm, Berlekamp-Massey algorithm and Xiao-Wei-Lam-lmamura algorithm, we can determine the linear complexity of any sequence over GF(pm) with the period 3n (n and pm - 1 are coprime) more efficiently.

关键词： number theory of the finite field, cryptography, stream cipher, fast algorithm.

Restricted parameter range promise set cover problems are easy

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Frontiers of Mathematics in China 2014年第6期9卷 1253-1260页

作者： hao chen Department of Mathematics Hangzhou Dianzi University Hangzhou 310018 China

The restricted parameter range set cover problem is a weak form of the NP-hard set cover problem with the restricted range of parameters. We give a polynomial time algorithm for this problem by lattices.

关键词： Set cover problem lattice closest vector problem (CVP) shortestvector problem (SVP)

Microstructures and corrosion properties of casting in situ Al_3Ti-Al composites

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Rare Metals 2010年第1期29卷 78-85页

作者： chen Tijun LI jian hao Yuan Gansu Key Laboratory of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050 China School of Material Science and Engineering Xi＇an Shiyou University Xi ＇an 710065 China

The effects of Ti content and the alloying elements of Si and Cu on the microstructures of casting in situ Al3Ti-Al composites were investigated. Simultaneously, their corrosion properties were also discussed. The results indicate that the aspect ratios of Al3Ti platelets in different Al based composites are different although all of them are in flaky shape. The morphologies of Al3Ti phase are not only determined by Ti content, but are also related to the alloying elements. The grain refining role of Al3Ti phase in the pure Al and Al-Cu based composites is more effective than that in the Al-Si based composite. The addition of Ti decreases the corrosion resistance of pure Al and Al alloys. The corrosion resistances of the composites are dependent on both the corrosion characteristics of the corresponding matrixes and the distribution of Al3Ti platelets.

关键词： metal matrix composite microstructure corrosion resistance alloying element morphology

Characterization of barrier-tunable radio-frequency-SQUID for Maxwell's demon experiment

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Chinese Physics B 2018年第6期27卷 507-512页

作者： Gang Li Suman Dhamala hao Li jian-She Liu Wei chen Tsinghua National Laboratory for Information Science and Technology Department of Microelectronics and Nanoelectronics Institute of Microelectronics Tsinghua University Beijing 100084 China Department of Physics and Astronomy University of Kansas Lawrence Kansas 66045 USA

We present the design, fabrication, and characterization of a barrier-tunable superconducting quantum interference device（SQUID） qubit for the study of Maxwell＇s demon experiment. In this work, a compound Josephson junction（CJJ）radio-frequency（RF）-SQUID qubit with an overdamped resistively shunted direct-current（DC）-SQUID magnetometer is used to continuously monitor the state of the qubit. The circuit is successfully fabricated with the standard Nb/Al-Al Ox/Nb trilayer process of our laboratory and characterized in a low noise measurement system, which is capable of measuring coherent dynamics of superconducting qubits, in an Oxford dilution refrigerator. All circuit parameters are determined accurately by fitting experimental data to theoretical analysis and simulation, which allows us to make a quantitative comparison between the results of the experiment and theory.

关键词： barrier-tunable RF-SQUID shunted DC-SQUID Maxwell's demon

Performance in Grain Yield and Physiological Traits of Rice in the Yangtze River Basin of China During the Last 60 yr

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Journal of Integrative Agriculture 2013年第1期12卷 57-66页

作者： ZHANG hao chen Ting-ting LIU Li-jun WANG Zhi-qin YANG jian-chang ZHANG jian-hua Key Laboratory of Crop Genetics and Physiology Education Department of Jiangsu Province/College of Agriculture Yangzhou University School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong Kong

Knowledge on the performance in grain yield and physiological traits is essential to understand the main yield-limiting factor and make strategies for breeding and crop management in rice （Oryza sativa L.）. This study investigated the changes in grain yield and associated physiological traits of rice in the Yangtze River Basin of China during the last 60 yr. Thirteen mid-season indica and 12 japonica rice cultivars that were popularly used were grown in the field in 2008 and 2009. The grain yield and yield components, biomass, leaf area, leaf photosynthesis, root oxidation activity, and harvest index were examined. The results showed that grain yield and grain yield per day have progressively increased during the years and such increases are mainly attributed to the expanded sink size as a result of more spikelets per panicle, especially for the case of super rice. Both biomass and harvest index were increased with the improvement of cultivars. Increase in biomass for modern rice cultivars was associated with an enhancement of leaf area and photosynthesis, root dry weight, and root oxidation activity, although the indica super rice cultivars showed a lower leaf photosynthetic rate and root oxidation activity than the semi-dwarf cultivars during the grain filling period. Both indica and japonica super rice cultivars exhibited a low percentage of filled grains, which may limit their great yield potential. All the data suggested that grain yield have been substantially improved during the 60 yr of rice breeding in the Yangtze River Basin. Expanded sink size, increased dry matter production and harvest index, and enhanced leaf area and photosynthesis, root dry weight, and root oxidation activity contribute to the improvement in grain yield. Increase in filling efficiency could realize the great yield potential in super rice.

关键词： rice yield performance grain filling physiological traits super rice

Spatial distribution of snow depth based on geographically weighted regression kriging in the Bayanbulak Basin of the Tianshan Mountains, China

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Journal of Mountain Science 2018年第1期15卷 33-45页

作者： LIU Yang LI Lan-hai chen Xi YANG Jin-Ming hao jian-Sheng State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia No.818 South Beijing Road Urumqi 830011 China Institute of Arid Ecology and Environment Xinjiang University Urumqi 830046 China

Snow depth is a general input variable in many models of agriculture,hydrology,climate and *** study makes use of observational data of snow depth and explanatory variables to compare the accuracy and effect of geographically weighted regression kriging(GWRK)and regression kriging(RK)in a spatial interpolation of regional snow *** auxiliary variables are analyzed using correlation coefficients and the variance inflation factor(VIF).Three variables,Height,topographic ruggedness index(TRI),and land surface temperature(LST),are used as explanatory variables to establish a regression model for snow *** estimated spatial distribution of snow depth in the Bayanbulak Basin of the Tianshan Mountains in China with a spatial resolution of 1 km is *** results indicate that 1)the result of GWRK's accuracy is slightly higher than that of RK(R^2=0.55 vs.R^2=0.50,RMSE(root mean square error)=0.102 m ***=0.077 m);2)for the subareas,GWRK and RK exhibit similar estimation results of snow *** in the Bayanbulak Basin with a snow depth greater than 0.15m are mainly distributed in an elevation range of 2632.00–3269.00 m and the snow in this area comprises 45.00–46.00% of the total amount of snow in this ***,the GWRK resulted in more detailed information on snow depth distribution than the *** final conclusion is that GWRK is better suited for estimating regional snow depth distribution.

关键词： Snow depth Spatial distribution Regression kriging Geographically weighted regression kriging

Joint relay station deployment and frequency reuse scheme for two-hop cellular networks

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The Journal of China Universities of Posts and Telecommunications 2012年第2期19卷 74-80页

作者： chen hao-kai YIN Hui LIANG jian LI Zhong-nian LIU Shou-yin Department of Electronic and Inlbrmation Engineering Central Chma Normal UniversityWuhan 430079China

To fully exploit the performance benefits of relay station （RS）, in the two-hop cellular networks covering hotspots, when the number of RSs is predetermined, both RS deployment and frequency reuse scheme are jointly optimized for the purpose of maximizing the system capacity based on the constraints of system demand of capacity and the maximum number of outage demand nodes （MNDN）. Further, considering the overhead of increasing RSs, it is desired to use minimum number of RSs. The joint RS deployment and frequency reuse scheme （JRDFR） problem is formulated into a mixed integer nonlinear programming, which is non-deterministic polynomial-time hard in general. A heuristic approach based on genetic algorithm is proposed to tackle the JRDFR problem. The computational experiment of the heuristic approach is achieved and optimized RS deployment and frequency reuse scheme is obtained. Finally, we discuss the impacts of MNDN and the number of RSs on the system performance.

关键词： relay station deployment frequency reuse scheme two-hop cellular networks

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爆炸作用下建筑结构高效毁伤评估方法

爆炸与冲击 2025年第1期45卷 015101-1-015101-18页

作者：吕晋贤吴昊卢永刚陈德同济大学土木工程学院上海200092 中国工程物理研究院总体工程研究所四川绵阳621999

为综合评估战后建筑结构的毁伤等级，针对爆炸作用下典型地面建筑，即含填充墙钢筋混凝土（reinforced concrete，RC）框架结构，提出了损伤破坏和倒塌的高精度数值仿真分析方法，并通过RC结构爆炸试验、倒塌事故和砌体墙爆炸试验进行... 详细信息

为综合评估战后建筑结构的毁伤等级，针对爆炸作用下典型地面建筑，即含填充墙钢筋混凝土（reinforced concrete，RC）框架结构，提出了损伤破坏和倒塌的高精度数值仿真分析方法，并通过RC结构爆炸试验、倒塌事故和砌体墙爆炸试验进行了充分验证;开展了典型3层原型RC框架结构在不同爆炸当量（25~200 kg TNT）下的内爆炸数值仿真，定量分析了爆炸冲击波在建筑结构内部的传播、结构损伤破坏和墙体飞散等。爆炸作用下建筑结构的高效毁伤评估流程为：结合镜像爆源和非线性叠加原理确定内爆炸荷载，基于等效单自由度方法评估梁、板、柱及墙体构件的毁伤等级，引入构件重要性系数加权确定房间毁伤等级，考虑房间功能及位置重要性评估整体结构的毁伤等级。高精度数值仿真分析与毁伤评估方法计算的典型RC框架结构的整体毁伤等级一致，即在25、100和200 kg TNT爆炸下RC结构分别呈现轻度、中度和重度毁伤，毁伤评估方法可缩短99%以上的计算耗时，兼具可靠性与时效性。

关键词：爆炸荷载建筑结构毁伤评估方法损伤破坏