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Predictive safety control for road vehicles after a tire blowout

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Science China(Information Sciences) 2018年第7期61卷 101-103页

作者： Fei WANG Hong CHEN Lulu GUO Yunfeng hu State Key Laboratory of Automotive Simulation and Control Jilin University Department of Control Science and Engineering Jilin University

Since driver error is considered a major cause in over 90%of all road crashes[1],driving assistance systems are widely used to improve driving safety,and are an important research direction in the intelligent vehicle *** the rapid development of sensing,identification and communication technologies,the vehicle can obtain an increasing amount of information in real time,ranging from the vehicle status information to road information

关键词： Predictive safety control for road vehicles after a tire blowout

Analysis of Two Public Key Cryptosystems Based on Randomized Knapsack Sequences

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Chinese Journal of Electronics 2014年第1期23卷 175-178页

作者： PENG Liqiang ZUO Jinyin hu Lei XU Jun State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences PLA Unit 95899

Two knapsack public key cryptosystems based on randomized knapsack sequences were proposed in2009 and 2011 respectively, where the secret knapsack sequence is transformed by secret modular linear transforms into one or three public randomized knapsack sequences with appropriate density. In this paper, we recover the secret modular linear transforms by simultaneous Diophantine approximation and propose secret key recovery attacks on these two cryptosystems. Practical attack experiments are done within one minute.

关键词： Knapsack public key cryptosystem Simultaneous Diophantine approximation Lattice L3 algorithm

A new optical field state as an output of diffusion channel when the input being number state

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1649-1653页

作者： FAN HongYi LOU SenYue PAN XiaoYin hu LiYun Department of Physics Ningbo University Department of physics Jiangxi Normal University

By analyzing theoretical scheme of quantum controlling through photon addition,we propose a new optical field whose density operator asρ=λ(1-λ)l:Ll(-λ2aa/1-λ)e-λaa:(here::denotes normal ordering symbol),which is named Laguerre-polynomialweighted chaotic *** show that such state is the solution to the master equation d/dtρ=-κ(aaρ+ρaa-aρa-aρa),describing a diffusion channel,with the initial number state|l l|,andλ=1/(1+κt).This new state is characteristic of possessing photon number l+κt at time t,so the photon number by adjusting the diffusion parameterκcan be *** master equation is solved using the summation method within ordered product of operators and the entangled state *** physical difference between the diffusion and the amplitude damping is noted.

关键词： photon addition Laguerre-polynomial-weighted chaotic state entangled state representation

Productivity effect and overuse of pesticide in crop production in China

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Journal of Integrative Agriculture 2015年第9期14卷 1903-1910页

作者： ZHANG Chao Guanming Shi SHEN Jian hu Rui-fa School of Management and Economics Beijing Institute of Technology Department of Agricultural and Applied Economics University of Wisconsin

Chinese farmers are often accused of overusing pesticides that play a crucial role in enhancing crop yield by reducing losses to crop pests. Pesticide overuse has caused a series of negative health and environmental externalities. This paper quantiifes the productivity effect and the optimal amount of pesticides in rice, cotton and maize production in China from the economic perspective. Using survey data col ected in 2012 and 2013, both Cobb-Douglas and Weibul damage control speciifcations are used to estimate the production function. Results show that pesticides have statistical y signiifcant pro-ductivity effect on crop yield. On the condition of Weibul damage control speciifcations, the marginal products of 1 kg of the active ingredients of pesticides for rice, cotton and maize are 71.06, 22.73 and 98.45 kg, respectively. However, 57, 64 and 17%of the actual amount of pesticides are overused for rice, cotton and maize, respectively. Moreover, the productivity effect of pesticides would be overestimated using Cobb-Douglas speciifcation without incorporating a damage control agent.

关键词： productivity effect damage control agent pesticide overuse marginal product

The dependence of sintering temperature on Schottky barrier and bulk electron traps of ZnO varistors

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Science China(Technological Sciences) 2011年第2期54卷 375-378页

作者： LIU Jun HE JinLiang hu Jun LONG WangCheng State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

In order to investigate the influence of sintering temperature on the Schottky barrier and bulk electron traps of ZnO varis- tors, ZnO-Bi2O3 based varistor ceramic samples were sintered at 1000, 1100, 1200 and 1300℃, respectively. The measured results indicate that the sample sintered at 1300℃ possesses the lowest voltage gradient and nonlinear coefficient, compared with other samples. The barrier height of the samples decreased as the sintering temperature increased, which resulted in the deterioration of nonlinearity. Furthermore, two bulk electron traps determined by admittance spectroscopy were generally independent of sintering temperature, which indicated that these two traps might originate from the intrinsic defects in ZnO lattice.

关键词： ZnO varistor sintering temperature Schottky barrier bulk electron trap admittance spectroscopy

Discovery and significance of microfossils from Qinbaikouian Dazhuang Formation in Luonan, Shaanxi Province

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Chinese Science Bulletin 1997年第3期42卷 243-245页

作者： Chen, Z hua, H Jian, WC hu, YX Department of Geology Northwest University Xi’an China Xi’an Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Xi’an China

THE microfossils were obtained by using 5%—7% HF acid from Qingbaikouian Dazhuang Formation in Luonan County, Shaanxi Province, with an age of 800—1000 Ma. The fossils may be one type of the oldest skeletal mierofos... 详细信息

关键词： microfossil Qinbaikouian Dazhuang Formation Shaanxi Province.

基于深度学习的基础设施表面裂纹检测方法研究进展

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计算机工程与应用 2025年第01期61卷 1-23页

作者：胡翔坤李华冯毅雄钱松荣李键李少波贵州大学公共大数据国家重点实验室清华大学机械工程系浙江大学流体动力基础件与机电系统全国重点实验室

民用基础设施在长期使用后容易发生物理结构或性能状态的改变，对其功能和使用安全造成一定的损害，因此，对这类设施的结构健康监测是十分必要的。裂纹检测是结构健康监测中极其重要的一部分，及时检测并识别这类损伤，能有效避免事故... 详细信息

民用基础设施在长期使用后容易发生物理结构或性能状态的改变，对其功能和使用安全造成一定的损害，因此，对这类设施的结构健康监测是十分必要的。裂纹检测是结构健康监测中极其重要的一部分，及时检测并识别这类损伤，能有效避免事故的发生。基于计算机视觉的表面裂纹检测方法操作简单、检测速度快、准确率高，被广泛应用于民用基础设施的表面裂纹检测。从图像分类、目标检测、语义分割三个不同的检测方向综述了基于深度学习的基础设施表面裂纹检测方法，总结了常见的数据采集方法和常用的公共裂纹数据集。最后讨论了基于深度学习的基础设施表面裂纹检测方法存在的困难与挑战，并展望了未来可能的发展方向。

关键词：结构健康监测裂纹检测计算机视觉深度学习

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Vinylpyridine-and vinylnitrobenzene-coating tetraphenylethenes：Aggregation-induced emission (AIE) behavior and mechanochromic property

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Chinese Chemical Letters 2018年第10期29卷 1489-1492页

作者： Xiaoxie Ma Linli hu Xie Han Jun Yin College of Chemistry and Environmental Engineering Yangtze University Jingzhou 434023 China Key Laboratory of Pesticide and Chemical Biology Ministry of Education College of Chemistry Central China Normal University Wuhan 430079 China

Two functional tetraphenylethylene derivatives modified by vinylpyridine and vinylnitrobenzene,respectively, were synthesized by Heck coupling reaction. Their optical behaviors were investigated. The results showed they had AIE activity in solution. The property in solid state displayed that both of them had reversible mechanochromism. Upon grinding, their fluorescence spectra showed around 13–40nm red-shift, and could return to the original state after solvent fuming. We believe that this work will be helpful for the design of stimuli-responsive materials in future.

关键词： Aggregation-induced emission Mechanochromism Tetraphenylethylene

Experimental study of high temperature particle dropping in coolant liquid

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Nuclear Science and Techniques 2007年第4期18卷 252-256页

作者： LI Tianshu YANG Yanhua LI Xiaoyan hu Zhihua School of Mechanical Power Engineering Shanghai Jiaotong University Shanghai 200030 China

A series of experiments of the premixing stage of fuel-coolant interactions (FCI), namely the particles falling into water, were carried out. The force on the particles during the course of falling has been studied. The dropping character of hot particle was influenced by three main parameters, i.e., particle temperature, particle diameter and coolant subcooling that varied over a wide range. A high-speed camera recorded the falling speed of the particle and the moving curves were obtained. The experimental results showed that for the film boiling on the surface of particle and water, the temperature increase of either particle or coolant would slow down the particle falling velocity. The falling velocity of particle in small diameter is lower than that of the bigger particle. The present work can provide an experimental foundation for further investigation of high-speed transient evaporation heat transfer.

关键词：蒸汽爆炸燃料冷却作用高温粒子热力学