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A Field Study on Effects of Nitrogen Fertilization Modes on Nutrient Uptake,Crop Yield and Soil Biological Properties in Rice-Wheat Rotation System

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Agricultural Sciences in China 2011年第8期10卷 1254-1261页

作者： GUAN Guan TU Shu-xin yang Jun-cheng ZHANG Jian-feng yang Li College of Resource and Environment Huazhong Agricultural UniversityWuhan 430070P.R.China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Plant Protection and Soil Fertilizer Hubei Academy of Agricultural SciencesWuhan 430064P.R.China

Rational application of nitrogen （N） fertilizers is an important measure to raise N fertilizer recovery rate and reduce N loss.A two-year field experiment of rice-wheat rotation was employed to study the effects of N fertilization modes including a N fertilizer reduction and an organic manure replacement on crop yield,nutrient uptake,soil enzyme activity,and number of microbes as well as diversity of *** result showed that 20% reduction of traditional N fertilizer dose of local farmers did not significantly change crop yield,N uptake,soil enzyme activity,and the number of microbes （bacteria,actinomycetes,and fungi）.On the basis of 20% reduction of N fertilizer,50% replacement of N fertilizer by organic manure increased the activity of sucrose,protease,urease,and phosphatase by 46-62,27-89,33-46,and 35-74%,respectively,and the number of microbes,i.e.,bacteria,actinomycetes,and fungi by 36-150,11-153,and 43-56%,***,organic fertilizer replacement had a Shannon＇s diversity index （H） of 2.18,which was higher than that of other modes of single N fertilizer *** results suggested that reducing N fertilizer by 20% and applying organic manure in the experimental areas could effectively lower the production costs and significantly improve soil fertility and biological properties.

关键词： rice-wheat rotation N fertilization mode organic manure replacement soil enzyme activity microbial diversity

Internet of Things Based Solutions for Transport Network Vulnerability Assessment in Intelligent Transportation Systems

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Computers, Materials & Continua 2020年第12期65卷 2511-2527页

作者： Weiwei Liu yang Tang Fei yang Chennan Zhang Dun Cao Gwang-jun Kim Business School University of Shanghai for Science and TechnologyShanghai200093China Zhejiang University Urban and Rural Planning&Design Institute Hangzhou310023China School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410004China Department of Computer Engineering Chonnam National UniversityGwangju61186Korea

Intelligent Transportation System(ITS)is essential for effective identification of vulnerable units in the transport network and its stable ***,it is necessary to establish an urban transport network vulnerability assessment model with solutions based on Internet of Things(IoT).Previous research on vulnerability has no congestion effect on the peak time of urban road *** cascading failure of links or nodes is presented by IoT monitoring system,which can collect data from a wireless sensor network in the transport *** IoT monitoring system collects wireless data via Vehicle-to-Infrastructure(V2I)channels to simulate key segments and their failure ***,the topological structure vulnerability index and the traffic function vulnerability index of road network are extracted from the vulnerability *** two indices are standardized by calculating the relative change rate,and the comprehensive index of the consequence after road network unit is in a failure ***,by calculating the failure probability of road network unit and comprehensive index of road network unit in failure state,the comprehensive vulnerability of road network can be evaluated by a risk calculation *** short,the IoT-based solutions to the new vulnerability assessment can help road network planning and traffic management departments to achieve the ITS goals.

关键词： Internet of Things Intelligent Transport Systems vulnerability assessment transport network

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 212-223页

作者： Xiao-hu MA Meng yang Zhao ZHANG School of Computer Science and Technology Soochow University State Key Laboratory for Novel Software Technology Nanjing University

The feature extraction algorithm plays an important role in face recognition. However, the extracted features also have overlapping discriminant information. A property of the statistical uncorrelated criterion is that it eliminates the redundancy among the extracted discriminant features, while many algorithms generally ignore this property. In this paper, we introduce a novel feature extraction method called local uncorrelated local discriminant embedding(LULDE). The proposed approach can be seen as an extension of a local discriminant embedding(LDE)framework in three ways. First, a new local statistical uncorrelated criterion is proposed, which effectively captures the local information of interclass and intraclass. Second, we reconstruct the affinity matrices of an intrinsic graph and a penalty graph, which are mentioned in LDE to enhance the discriminant property. Finally, it overcomes the small-sample-size problem without using principal component analysis to preprocess the original data, which avoids losing some discriminant information. Experimental results on Yale, ORL, Extended Yale B, and FERET databases demonstrate that LULDE outperforms LDE and other representative uncorrelated feature extraction methods.

关键词： Feature extraction Local discriminant embedding Local uncorrelated criterion Face recognition

Static aeroelastic analysis including geometric nonlinearities based on reduced order model

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Chinese Journal of Aeronautics 2017年第2期30卷 638-650页

作者： Xie Changchuan An Chao Liu Yi yang Chao School of Aeronautic Science and Engineering Beihang University Beijing 100083 China

This paper describes a method proposed for modeling large deflection of aircraft in nonlinear aeroelastic analysis by developing reduced order model（ROM）.The method is applied for solving the static aeroelastic and static aeroelastic trim problems of flexible aircraft containing geometric nonlinearities;meanwhile,the non-planar effects of aerodynamics and follower force effect have been *** are computational inexpensive mathematical representations compared to traditional nonlinear finite element method（FEM） especially in aeroelastic *** approach for structure modeling presented here is on the basis of combined modal/finite element（MFE） method that characterizes the stiffness nonlinearities and we apply that structure modeling method as ROM to aeroelastic ***,the non-planar aerodynamic force is computed by the non-planar vortex lattice method（VLM）.Structure and aerodynamics can be coupled with the surface spline *** results show that both of the static aeroelastic analysis and trim analysis of aircraft based on structure ROM can achieve a good agreement compared to analysis based on the FEM and experimental result.

关键词： Aeroelasticity Finite element method Geometric nonlinearity Reduced order models Trims

A Reliability Allocation Method of CNC Lathes Based on Copula Failure Correlation Model

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 128-136页

作者： Hao Wang Yi-Min Zhang Zhou yang School of Mechanical Engineering and Automation Northeastern University Shenyang 110819 China Equipment Reliability Institute Shenyang University of Chemical Technology Shenyang 110142 China

The current research of reliability allocation of CNC lathes always treat CNC lathes as independent series systems. However, CNC lathes are complex systems in the actual situation. Failure correlation is rarely considered when reliabil?ity allocation is conducted. In this paper, drawbacks of reliability model based on failure independence assumption are illustrated, after which, reliability model of CNC lathes considering failure correlation of subsystems is established based on Copula theory, which is an improvement of traditional reliability model of series systems. As the failure time of CNC lathes often obeys Weibull or exponential distribution, Gumbel Copula is selected to build correlation model. After that, a reliability allocation method considering failure correlation is analyzed based on the model established before. Reliability goal is set first and then failure rates are allocated to subsystems according to the allocation vector through solving the correlation model. Reliability allocation is conducted for t = 1. A real case of a CNC lathe and a numerical case are presented together to illustrate the advantages of the reliability model established consider?ing failure correlation and the corresponding allocation method. It shows that the model accords to facts and real working condition more, and failure rates allocated to all the subsystems are increased to some extent. This research proposes a reliability allocation method which takes failure correlation among subsystems of CNC lathes into consid?eration, and costs for design and manufacture could be decreased.

关键词： CNC lathe Copula Failure correlation Reliability model Reliability allocation

Valuating service loss of snow cover in Irtysh River Basin

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Advances in Climate Change Research 2019年第2期10卷 109-114页

作者： yang yang WU Xue-Jiao LIU Shi-Wei XIAO Cun-De WANG Xiaoming State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Etivironment and Resources Chinese Academ y o f Sciences Lanzhou 730000 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Earth Surface Processes and Resources Ecology Beijing Normal University Beijing 100875 China

Snow cover provides essential resources and services for human well-being and socioeconomic development in arid areas. With the change in snow cover resulting from climate change that causes concerns about its consequences, there is a pressing need to analyze and understand its impact on the benefits that people has been enjoying from snow cover. These can be derived from the variation in economic value of snow services, that are demanded to meet socioeconomic activities. Based on the average decline mass of snow cover from 1979 to 2016 in Irtysh River Basin, we use the approach by applying economic evaluation to estimate the annual value loss of snow services. Considering the decreasing trend of snow cover mass at rates of 10.2 Mt per year (p < 0.05) or 0.3% per year, the annual service loss in Irtysh River Basin is currently worth up to CN 196 million. Within it, the service loss of climate regulation contributes the most, or about CN 84.7 million. The loss of freshwater service contributes only about 19%, implying that there would be a significant underestimation of service loss if only water supply would be considered. This may cause biased decision-making when we are facing the challenges of declining services as a result of climate change, impacting on the balancing of socioeconomic development and environment conservation for the sustainability over a long term.

关键词： Cryosphere science Climate change Snow cover Cryosphere service Service value Irtysh river basin

Site-Selective Magnetic Moment Collapse in Compressed Fe_(5)O_(6)

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Chinese Physics Letters 2021年第8期38卷 151-155页

作者： Qiao-Ying Qin Ai-Qin yang Xiang-Ru Tao Liu-Xiang yang Hui-yang Gou Peng Zhang MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

Iron oxide is one of the most important components in the Earth’s *** recent discovery of the stable presence of Fe_(5)O_(6) in the Earth’s mantle environment has stimulated significant interests in understanding of this new category of iron *** report the electronic structure and magnetic properties of Fe_(5)O_(6) calculated by the density functional theory plus dynamic mean field theory(DFT+DMFT)*** calculations indicate that Fe_(5)O_(6) is a conductor at ambient pressure with dominant Fe-3 d density of states at the Fermi *** magnetic moments of iron atoms at three non-equivalent crystallographic sites in Fe_(5)O_(6) collapse at significantly different rates under *** site-selective collapse of magnetic moments originates from the shifting of energy levels and the consequent charge transfer among the Fe-3 d orbis when Fe_(5)O_(6) is being *** simulations suggest that there could be high conductivity and volume contraction in Fe_(5)O_(6) at high pressure,which may induce anomalous features in seismic velocity,energy exchange,and mass distribution in the deep interior of the Earth.

关键词： theory magnetic

Simulated Impacts of Sulfate and Nitrate Aerosol Formation on Surface-Layer Ozone Concentrations in China

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Atmospheric and Oceanic Science Letters 2014年第5期7卷 441-446页

作者： yang yang LIAO Hong LOU Si-Jia State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The authors quantify the impacts of sulfate and nitrate aerosol formation on surface-layer 03 concentrations over China using the one-way nested-grid capa- bility of the global three-dimensional Goddard Earth Ob- serving System chemical transport model （GEOS-Chem）. Chemical reactions associated with sulfate formation are simulated to generally increase 03 concentrations in China. Over the North China Plain （NCP） and the Si- chuan Basin （SCB）, where simulated sulfate concentra- tions are the largest, ozone concentrations show maximum increases in spring by 1.8 ppbv （3.2%） in the NCP and by 2.6 ppbv （3.7%） in the SCB. On the contrary, nitrate formation is simulated to reduce 03 concentrations by up to 1.0 ppbv in eastern China, with the largest reduc- tions of 1.0 ppbv （1.4%） in summer over the NCE Ac- counting for the formation of both sulfate and nitrate, the surface-layer O3 concentrations over a large fraction of eastern China are simulated to increase in winter, spring, and autumn, dominated by the impact of sulfate forma- tion, but to decrease in summer because of the dominant contribution from nitrate formation.

关键词： ozone sulfate nitrate air quality

Long-term outcome of indwelling colon observed seven years after radical resection for rectosigmoid cancer: A case report

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World Journal of Clinical Cases 2021年第19期9卷 5252-5258页

作者： Zi-Xuan Zhuang Ming-Tian Wei Xu-yang yang yang Zhang Wen Zhuang Zi-Qiang Wang Department of Gastrointestinal Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Indwelling colon is characterized by an excluded segment of the colon after surgical diversion of the fecal stream with colostomy so that contents are unable to pass through this part of the *** report a rare case of purulent colonic necrosis that occurred 7 years after surgical colonic *** SUMMARY A 73-year-old male had undergone extended radical resection for rectosigmoid *** invaded ileocecal area and sigmoid colon were removed during the procedure,and the ileum was anastomosed side-to-side with the *** excluded ascending,transverse,and descending colon were sealed at both ends and left in the *** 7 years,the patient developed persistent abdominal pain and ***-up indicated intestinal *** patient underwent ultrasound-guided catheter drainage of the descending colon and a large amount of viscous liquid was drained,but the symptoms persisted;therefore,surgery was ***,extensive adhesions were found in the abdominal cavity,and the small intestine and the indwelling colon were widely *** dilated colon was 56 cm long,5 cm wide(diameter),and contained about 1500 mL of viscous *** indwelling colon was surgically removed and its histopathological examination revealed colonic congestion and necrosis with hyperplasia of granulation *** bacterial culture of the secretions was *** patient recovered after the *** Although colonic exclusion is routinely performed,this report aimed to increase awareness regarding the possible long-term complications of indwelling colon.

关键词： Colon Colectomy Intestinal obstruction Diversion colitis Sigmoid cancer Colitis Case report