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Saline water Irrigation Scheduling Through a Crop-water-Salinity Production Function and a Soil-water-Salinity Dynamic Model

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Pedosphere 2007年第3期17卷 303-317页

作者： WANG Yang-Ren KANG Shao-Zhong LI Fu-Sheng ZHANG Lu ZHANG Jian-Hua center for Agricultural water research in china China Agricultural University Beijing 100083 （China） Department of water Conservancy engineering Tianjin Agricultural University Tianjin 300384 （China） Agricultural College Guangxi University Nanning 530005 （China） CSIRO Land and-water GPO Box 1666 Canberra ACT 2601 （Australia） Department of Biology Hong Kong Baptist University Kowloon Tang Hong Kong （China）

Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water.

关键词： crop-water-salinity production function irrigation scheduling saline water irrigation water-salinity dy- namic model

A highly efficient electric additive for enhancing photovoltaic performance of dye-sensitized solar cells

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Science china Chemistry 2010年第6期53卷 1352-1357页

作者： LAN Zhang,WU JiHuai,LIN JianMing & HUANG MiaoLiang engineering research center of Environment-Friendly Functional Materials,Ministry of Education Key Laboratory of Functional Materials for Fujian Higher Education Institute of Materials Physical Chemistry,Huaqiao university,Quanzhou 362021,china 1. engineering research center of Environment-Friendly Functional Materials Ministry of Education Key Laboratory of Functional Materials for Fujian Higher Education Institute of Materials Physical Chemistry Huaqiao University Quanzhou 362021 China

N-cetylpyridinium iodide (N-CPI) as a new electric additive for enhancing photovoltaic performance of the dye-sensitized solar cell (DSSC) was *** showed high efficiency for enhancing both the open-circuit voltage and the short-circuit current density of DSSC when the suitable amount of N-CPI as 0.02 M was added in liquid *** energy conversion effi- ciency of DSSC increased from 4.429% to 6.535%,with 47.55% ***,it is a highly efficient electric addi- tive for *** intrinsic reason is owing to the special molecular structure of N-CPI,which contains two different polarity *** a surfactant,N-CPI could form ordered arrangement in liquid electrolyte,which affects the diffusing ability and the redox reaction of I-/I3-,and further affects the photovoltaic performance of DSSC.

关键词： dye-sensitized solar cell electric additive photovoltaic performance N-cetylpyridinium iodide Dapp

An improved approach to the efficient construction of and search operations in motion graphs

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Science china(Information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2,CHEN MinGang 3 & SHEN Yang 3 1 Software engineering Institute,East china Normal university,Shanghai 200062,china 2 Department of Computer Science and engineering,East china university of Science and Technology,Shanghai 200237,china 3 Department of Computer Science and engineering,Shanghai Jiao Tong university,Shanghai 200240,china 1. Software engineering Institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(Information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2,SUN LiXin 1,LI Yong 2 & JIA ShiLou 3 1 School of Computer Science and Telecommunication engineering,Jiangsu university,Zhenjiang 212013,china 2 research center for Wireless Communication,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,china 3 Communication research center,Harbin Institute of Technology,Harbin 150001,china 1. School of Computer Science and Telecommunication engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

Spray and forward:efficient routing based on the Markov location prediction model for DTNs

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Science china(Information Sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2 & LONG KePing2 1 research center for Optical Internet and Mobile Information Networks(COIMIN),university of Electronic Science and Technology of china,Chengdu 611731,china 2 School of Computer and Communications engineering,university of Science and Technology Beijing,Beijing 100083,china 1. research center for Optical Internet and Mobile Information Networks (COIMIN) University of Electronic Science and Technology of China Chengdu 611731 China2. School of Computer and Communications Engineering University of Science and Technology Beijing Beijing 100083 China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

A Multi-objective Optimal Approach to Automated Construction of Sacrificial Multi-piece Molds

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Journal of Shanghai Jiaotong university(Science) 2008年第5期13卷 542-546页

作者：王会凤周雄辉陈巍 national Die and Mold CAD engineering research center Shanghai Jiaotong University

Sacrificial multi-piece molds can be used for producing complex parts. To obtain the optimal design of molds automatically, a multi-objective optimal approach is proposed. Mold pieces number, material utilization and partitioning area are taken as the objective functions, and the machinability of each mold piece is taken as constraint condition. Genetic algorithm (GA) is adopted to realize global optimization of partitioning process. Each mold piece in optimal scheme can be manufactured by milling and drilling operations, which reduce the tooling cost and shorten product cycle obviously. Using the proposed approach, mold design can be significantly automated for making complex parts.

关键词： sacrificial multi-piece molds multi-objective optimization machinability genetic algorithm (GA)

Estimates of genetic and phenotypic parameters for weight and length in Paralichthys olivaceus(Temminck et Schlegel)

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Acta Oceanologica Sinica 2011年第6期30卷 58-64页

作者： TIAN Yongsheng XU Tianjun LIANG You CHEN Songlin Key Laboratory for Sustainable utilization of Marine Fisheries resources Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China Laboratory for Marine Living resources and Molecular engineering College of Marine ScienceZhejiang Ocean University Zhoushan 316000 China

The complete diallel cross design was employed to estimate the genetic parameters of the growth of Japanese flounder （Paralichthys olivaceus）. A total of 60 full-sib families were cultivated and two growth-related traits, body weight （BW） and body length （BL）, were examined at average 2, 3 and 8 months of age respectively, with 1 800 individuals measured in each age group （30 per family）. Based on the additive-dominance-maternal-effect genetic analysis model, the restricted maximum likelihood approach was used to estimate various （co）variance components. The results showed that narrow-sense heritability estimates of BW and BL were respectively： 0.29 ± 0.01 and 0.22 ± 0.02 at 2 months of age, 0.32 ± 0.02 and 0.30 ± 0.04 at 3 months of age, 0.48 ± 0.04 and 0.40 ± 0.05 at 8 months of age; broad-sense heritability estimates were respectively： 0.44 ± 0.02 and 0.54 ± 0.04 at 2 months of age, 0.35 ± 0.01 and 0.36 ± 0.03 at 3 months of age, 0.49 ± 0.03 and 0.45 ± 0.04. All heritabilities were statistically significant （P 0.05）. Additive genetic correlations between BW and BL at 2, 3 and 8 months of age were consistently positive and highly significant （P 0.01）： 0.93 ± 0.02, 0.95 ± 0.03 and 0.92 ± 0.03 respectively. Maternal effect was significant （P 0.05） only at 2 months of age, and was not detected at 3 and 8 months of age. According to the heritability estimates, the mass selection strategy should be efficient for the breeding of Japanese flounder.

关键词： Paralichthys olivaceus heritability genetic correlation genetic mating design diallel cross maternal effect

efficient video cutout based on adaptive multilevel banded method

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Science china(Information Sciences) 2012年第5期55卷 1082-1092页

作者： CHEN MinGang 1,SUI BoCong 1,GAO Yan 2 & MA LiZhuang 1 1 Department of Computer Science and engineering,Shanghai Jiao Tong university,Shanghai 200240,china 2 Software engineering Institute,East china Normal university,Shanghai 200062,china 1. Department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 200240 China2. Software Engineering Institute East China Normal University Shanghai 200062 China

Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout *** this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video *** our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph *** construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during *** results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

关键词： video object cutout multilevel band graph cuts video segmentation

Degradation of lignite model compounds by the action of white rot fungi

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Mining Science and Technology 2010年第1期20卷 76-81页

作者： DU Ying, TAO Xiuxiang, SHI Kaiyi, LI Yang School of Chemical engineering and Technology, china university of Mining & Technology, Xuzhou 221000, china [a] School of Chemical engineering Technology China University of Mining & Technology Xuzhou 221000 China

Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the strains were determined to study mycelium dry weight and protein content changes. Gas chromatography and infrared spectroscopy were used to detect changes of functional groups before and after the action of the fungi on the model compounds. Possible decomposition products and degrada-tion mechanisms were proposed. The research findings show that C. Versicolor and Golden Mushroom can grow in presence of the model compounds. The optimum culture conditions were a pH of 6.0, a carbon-nitrogen ratio of five and a Tween-80 concentration of 0.1%. Newly produced substances were found by gas chromatography. Infrared analysis showed that the model compounds degraded under the action of the microorganisms.

关键词： coal biotransformation white rot fungi mechanism model compound