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Effects of temperature and organic and inorganic nutrients on the growth of Chattonella marina (Raphidophyceae)from the Daya Bay,South china Sea

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Acta Oceanologica Sinica 2011年第3期30卷 124-131页

作者： WANG Zhaohui YUAN Meiling LIANG Yu LU Sollghui College of Life Science and Technology Jinan University Guangzhou 510632 China engineering research center of Tropical and Subtropical Aquatic Ecological engineering Ministry of Education Guangzhou 510632 China

The effects of temperature and different forms of nutrients on Chattonella marina growth have been investigated in strains isolated from the Daya Bay, the South china Sea. The strain of C. marina preferred high temperatures, with an optimal temperature of 25℃, and 18℃ was the minimum for its survival. Higher cell number and growth rate were obtained in high nitrogen and phosphorus concentrations （500 μg/L, 74μg/L） than under nutrient limitation. Nitrogen influenced the growth most, as the specific growth rate and maximum cell density were lower in nitrogen- limited cultures than noted under phosphorus limitation or under limitation from both. C. marina was capable of using many kinds of organic nitrogen sources including L-serine （L-Ser）, glycine （Gly）, alanine （Ala）, L-threonine （L-Thr）, glutamic acid （Glu） and urea, but could not utilize uric acid. Various forms of organic phosphorus compound such as glucose-6-phosphate （G6P）, sodium glycerophosphate （GYP）, adenosine triphosphate （ATP）, adenosine monophosphate （AMP）, cyti- dine monophosphate （CMP）, guanosine monophosphate （GMP）, uridine monophosphate （UMP）, 4-nitrophenylphosphate （NPP） and triethyl phosphate （TEP） supported the growth as well. Algal cells had the ability to sustain growth under nitrogenand/or phosphorus-free conditions particularly under phosphorus depleted condition. These results led to the hypothesis that high loading of nitrogen has played an important role in frequent C. marina blooms in the past decade, and its capability for utilization of diverse forms of organic nutrients and growth in low nutrient conditions make this species a likely recurrent dominant in the Daya Bay phytoplankton assemblages, visible as more frequent blooms.

关键词： Chattonella marina growth inorganic and organic nutrients salinity temperature

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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 Software engineering Institute East China Normal University Shanghai China Department of Computer Science and engineering East China University of Science and Technology Shanghai China Department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 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

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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 Department of Computer Science and engineering Shanghai Jiao Tong University Shanghai China Software engineering Institute East China Normal University Shanghai 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

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High Energy Micro-arc Alloying of ZM5 Mg Alloy by Mg-Y Electrode under Liquid

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稀有金属材料与工程 2011年第S4期40卷 181-184页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing research center,College of Materials and Metallurgy,Wuhan University of Science& Technology,Wuhan 430081,china Wuhan Univ Sci &Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

High-energy micro-arc alloying (HEMAA) is a consumable electrode,micro-welding process which uses electrical pulses that are typically three orders of magnitude shorter than in other pulse welding *** durations of a few microseconds combined with pulse frequencies in the 0.1 to 2-kilohertz range thus allow substrate heat dissipation over ～99% of the duty cycle while heating only about 1%.The cooling rates may approach 105 to 106 ℃/s,depending on *** obtained coating can produce unique corrosion and tribological *** require no special surface preparation and nearly any metal,alloy or cermets can be applied to metal *** paper details experimental results when alloying Mg base alloy ZM5,using Mg-Y electrodes with a water-based dielectric *** morphology and the composition of the alloying was analyzed by scanning electron microscope(SEM) and energy dispersive X-ray analysis(EDX).At the discharge energies employed,a thin recast layer thickness and rougher layers were formed on the *** layers were in general *** analysis showed that the Y transferred from the solid electrodes to the workpiece surface.

关键词： high-energy micro-arc alloying (HEMAA) surface alloying/modification Mg alloy Mg-Y

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Fabrication and Properties of Multilayer Chitosan Membrane Loaded with Tinidazole

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Journal of Wuhan University of Technology(Materials Science) 2007年第1期22卷 102-107页

作者：洪华刘昌胜 engineering research center of Biomedical Materials under Ministry of Education East China University of Science and Technology

With the aim of providing effective periodontal disease therapeutic method, multilayer membranes which were loaded with drug for guided tissue regeneration were prepared using an immerseprecipitation phase inversion technique. Single layer, bi-layer and tri-layer membranes were fabricated with chitosan used as cartier and tinidazole as medicine model which was loaded on the membrane. The influence of layer on structure and properties of membrane were studied by SEM, UV spectrophotometer and mechanical test. Drug release properties of three types of layer membranes were also investigated. The results showed that release rate could be slown down in both bi-layer and tri-layer membranes （to 11 days and 14 days respectively） and tri-layer membrane lasted the longest. After a process of rapid release, the concentration of tinidazole which was released by the membrane was maintained at an efficient dosage level. Compared with single layer and bi- layer membranes, we found tri-layer membrane could play a role in controlling low-rate drug release especially at the early stage of release, and keep an efficient dosage at affected part for a long period of time. The loss of drug which loaded on membrane decreased from 84.6% for single layer to 13.04% for tri-layer. The mechanical strength of three types of membrane were detected and showed that it could meet the requiremens of clinical practice. The membranes especially with tri-layer could be more valuable in application.

关键词： chitosan membrane multilayer drug loss release rate

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IFNN时变模型在建立大坝位移监控中的应用

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水电能源科学 2008年第5期26卷 101-103页

作者：武金坤李波河海大学水利水电工程学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对时变监控模型比常规监控模型更有效且能准确进行变量分离,通过改进的模糊神经网络(IFNN)结合时变模型对陈村水库大坝的水平位移进行拟合与预测,并与BP模型做了比较。结果表明,该模型拟合及预测精度均较BP模型高,与工程实例相近,可... 详细信息

针对时变监控模型比常规监控模型更有效且能准确进行变量分离,通过改进的模糊神经网络(IFNN)结合时变模型对陈村水库大坝的水平位移进行拟合与预测,并与BP模型做了比较。结果表明,该模型拟合及预测精度均较BP模型高,与工程实例相近,可推广应用。

关键词：时变模型 BP模型改进的模糊神经网络水平位移

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Energy-efficient power allocation for selfish cooperative communication networks using bargaining game

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Science china(Information Sciences) 2012年第4期55卷 795-804页

作者： DING EnJie 1,ZHANG GuoPeng 1,LIU Peng 1 & YANG Kun 2 1 CUMT-IoT Perception Mine research center,china University of Mining and Technology,Xuzhou 221116,china 2 School of Computer Science and Electronic engineering,University of Essex Wivenhoe Park,Colchester Essex,CO4 3SQ,UK CUMT-IoT Perception Mine research center China University of Mining and Technology Xuzhou China School of Computer Science and Electronic engineering University of Essex Wivenhoe Park Colchester Essex UK

In commercial networks,user nodes operating on batteries are assumed to be selfish to consume their energy solely to maximize their own benefits,e.g.,data *** this paper,we propose a bargaining game to perform the power allocation for the selfish cooperative communication *** our system,two partner nodes can act as a source as well as a relay for each other,and each node is with an energy constraint to transmit one *** a selfish node is willing to seek cooperative transmission only if the data rate achieved through cooperation will not lower than that achieved through noncooperation by using the same amount of *** energy-efficient power allocation problem can be modeled as a cooperative *** proved that there exists a unique Nash bargaining solution (NBS) for the game by verifying that the game is indeed a bargaining ***,the two objectives,i.e.,system efficiency and user fairness specified in the selfish networks can be *** results show that the NBS scheme is efficient in that the performance loss of the NBS scheme to that of the maximal overall rate scheme is small while the maximal-rate scheme is *** simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance.

关键词： cooperative communication energy efficiency resource allocation cooperative game theory Nash bargaining solution

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Surface Top Graphology,Corrosion and Microhardness of Oxygen Diffusion Hardened Pure Titanium Alloy TA4 after Laser Surface Melting

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稀有金属材料与工程 2011年第S4期40卷 185-189页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing research center,College of Materials and Metallurgy,Wuhan University of Science& Technology,Wuhan 430081,china Wuhan Univ Sci & Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

In the oxygen diffusion hardened condition,untreated and laser surface melted pure titanium alloy (TA4) by Nd:YAG pulsed laser,are hardened at temperatures of 650 to 700℃ with the end result being a passive,mechanically stable,abrasion resistant oxide ceramic rutile surface *** thickness of this surface layer depends on the time,temperature,and the microstructure of the Ti *** paper describes the results of x-ray diffraction analysis,scanning electron microscope (SEM),microhardness measurements,and corrosion resistance measurements of hardened pure and laser treated Ti *** oxygen diffusion hardened titanium alloy after laser surface melted samples (L-TA4) had a more pronounced grain structure and significantly higher roughness values than the untreated pure TA4 (U-TA4)*** L-TA4 samples also exhibited at least equivalent corrosion behavior and a definite increase in surface hardness compared to the U-TA4 *** results of this work suggest that laser surface melting plays a key role for effective oxygen diffusion hardening at 650-700℃ for pure and laser treated pure Ti alloys.

关键词： oxygen diffusion harden (ODH) titanium alloy laser surface melting corrosion

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Identifying heavy hitters in high-speed network monitoring

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Science china(Information Sciences) 2010年第3期53卷 659-676页

作者： ZHANG Yu1, FANG BinXing1,2 & ZHANG YongZheng2 1research center of Computer Network and Information Security Technology, Harbin Institute of Technology, Harbin 150001, china 2research center of Information Security, Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100190, china research center of Computer Network and Information Security Technology Harbin Institute of Technology Harbin China research center of Information Security Institute of Computing Technology Chinese Academy of Sciences Beijing China

Identifying heavy hitters in a network traffic stream is important for a variety of network applications ranging from traffic engineering to anomaly detection such as detection of denial-of-service attacks. Existing methods generally examine newly arriving items in the stream, perform a small number of operations using a small amount of memory, and still provide guarantees on the identifying accuracy. In high-speed network monitoring, the update speed per item is extremely critical. However, so far as we know, there are no identifying algorithms which can provide constant update time (O(1)) in a weighted data stream. In this paper, we present an algorithm named Weighted Lossy Counting (WLC) which is able to identify heavy hitters in a high-speed weighted data stream with constant update time. WLC employs a novel efficient partially ordered data structure which is able to provide a fast per-item update speed while keeping the memory cost relatively low. We compare WLC with state-of-the-art algorithms for finding heavy hitters in real traffic traces. The experimental results show that WLC performs well in accuracy (recall, precision and average relative error) as other algorithms; moreover it has a much higher update speed at the cost of relatively larger memory space used. A theoretical worst-case memory bound of WLC is also derived in this paper; however, experiments with long real traffic traces show that WLC requires much less space than the theoretical bound in practice.

关键词： network traffic monitoring heavy hitter weighted data streams

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Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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Science china Chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao Beijing national Laboratory for Molecular Sciences,State Key Laboratory for Structural Chemistry of Stable and Unstable Species Green Chemistry center,College of Chemistry and Molecular engineering,Peking University,Beijing 100871,china Beijing national Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing China Green Chemistry center College of Chemistry and Molecular Engineering Peking University Beijing China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1,2-propanediol,and especially 1,2,5-pentanetriol were obtained with selectivities of 15%,14% and 22%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

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