检索结果-南通市图书馆

Solvability of Elliptic Boundary Value problems without Standard Landesman-Lazer Condition

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2000年第2期16卷 349-359页

作者： Zhiqing Han Department of Applied Mathematics.dalian University of Technology,dalian 116024,p.r.china Department of Applied Mathematics Dalian University of Technology Dalian 116024 P. R. China

In this paper we prove a very general result concerning solvability of the resonant problem: Δu+λku+g（x, u）=h（x）;u=0, xΩ, which immediately gives three generalized Landesman-Lazer conditions. The most interesting application of the general result is concerned with the problem when λk=λ1. in which case we prove solvability results for it under conditions which are not the standard Landesman-Lazer condition or only partly enjoy it. Furthermore, we propose a new sign condition and give a comprehensive extension of a main result of Figueiredo and Ni.

关键词： Elliptic boundary value problems Leray-Schauder degree continuation method Landesman-Lazer condition Semi-Landesman-Lazer conditions Sign condition

THE CALCULATION OF IN-LINE FOrCE ON A VErTICAL CIrCULAr CYLINDEr AND ANALYSIS OF HYDrODYNAMIC COEFFICIENTS C_D AND C_M IN WAVE-CUrrENT CO-EXISTING FIELD

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1991年第2期3卷 29-41页

作者： Kang Hai-gui Li Yu-cheng Wang Hong-rong, dalian University of Technology, dalian 116024, p.r.china dalian Univ of Technology Dalian China

The purpose of this paper is to find some better methods for calculating in-line forces on a vertical circular cylinder and for analysing the hydrodynamic coefficients C_D and C_M in wave-current co-existing field. In this pa- per, in order to calculate hydrodynamic forces, the authors try to find a way of applying a great number of the re- sults about C_D and C_M for wave-only field in the case of wave-current co-existing field, and the results about C_D and C_M obtained in regular waves in the ease of irregular waves. Such a way may be of significance in engineering and further research.

关键词： THE CALCULATION OF IN-LINE FOrCE ON A VErTICAL CIrCULAr CYLINDEr AND ANALYSIS OF HYDrODYNAMIC COEFFICIENTS C_D AND C_M IN WAVE-CUrrENT CO-EXISTING FIELD LINE CO

The Micro/Nanostructure Characteristics and the Mechanical properties of Hemifusus tuba Conch Shell

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2010年第4期7卷 3+308-313页

作者： Yan Liang~1,Jie Zhao~2,Chengwei Wu~1 1.State Key Laboratory of Structural Analysis for Industrial Equipment,Department of Engineering Mechanics,dalian University of Technology,dalian 116024,p.r.china 2.School of Materials Science and Engineering,dalian University of Technology,dalian 116024,p.r.china State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian P. R. China School of Materials Science and Engineering Dalian University of Technology Dalian P. R. China

The mollusk shell mobilizes calcium from environment for skeletal *** occurs through synthesizing solidsin solution in the presence of organic molecules of specific interior regions of the conch *** ultrastructure and microhardnessof the Hemifusus tuba conch shell living in the Huang/Bo sea area are investigated in the *** is shown that thecomposition and microstructure of the mollusk shell vary in different *** prodissoconch shell consists only of aragonitewith the crossed-lamellar *** the spiral shell and the body shell of the Hemifusus tuba conch shell arecomposed of one calcite layer and several aragonite *** calcite layer consists of cylindrical grains,but the aragonitelayers are crossed-lamellar ultrastructure at three size *** minimum structure size (the third-order lamella) is at about20 nm - 80 *** margin of shell aperture is only composed of calcite with cylindrical *** natural optimization of theshell microstructure is intimately due to the growth of the Organic *** different positions the microhardness of molluscshell is different due to different crystal structures and crystal *** growth process of shells allows a constantrenewal of the material,thus enabling their functional adaptation to external environments.

关键词： conch shell microstructure aragonite calcite crossed-lamellar

FUZZY OpTIMAL DECISIONS FOr MULTIOBJECTIVE FLOOD CONTrOL SYSTEM OF CASCADE rESErVOIrS

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1999年第3期11卷 6-13页

作者： Cheng Chun tian Civil Engineering Department, dalian University of Technology,dalian 116023, p.r.china (received June 13,1998)

Based on the practice of reservoir operation, a decision making model of multi objective flood control of cascade reservoir system is presented, which is realistic and effective, combining traditional optimal techniques with fuzzy set theory. In the present paper, the operation alternative is chosen as the decision variable, the outflow process as the state variable, and optimal operation decisions are determined by the fuzzy optimal technique. Finally, the model is delineated by taking a case study of comprehensive flood operation for a cascade reservoir system.

关键词： multiobjective flood control multireservoir flood control fuzzy optimal decision recursion matrix

Incoherent control of two classes of finite-level quantum systems

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2011年第4期22卷 679-683页

作者： Chunlin Chen 1,2 and Zhenquan Qin 3,1.Department of Control and System Engineering,Nanjing University,Nanjing 210093,p.r.china 2.State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing 210093,p.r.china 3.School of Software,dalian University of Technology,dalian 116620,p.r.china Department of Control and System Engineering Nanjing University Nanjing 210093 P. R. China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 P. R. China School of Software Dalian University of Technology Dalian 116620 P. R. China

The incoherent control of finite-level quantum systems is investigated. Following a brief introduction to coherent control paradigms in quantum control, a control problem that can not be accomplished using only coherent control is presented. For such a control problem, it is proved that it can be accomplished using incoherent control based on projective measurement and coherent control for two classes of finite-level quantum systems, i.e., eigenstate controllable quantum systems and wavefunction controllable quantum systems.

关键词： quantum control eigenstate controllability wavefunction controllability coherent control incoherent control.

THE rOTATIONALLY pErIODIC SYMMETrY IN BEM

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 1994年第3期7卷 235-244页

作者： Yang Haitian (Department of Engineering Mechanics,dalian University of Technology,p.r.china)Wu Gaofeng Wu Jingning (research Institute of Engineering Mechanics,dalian University of Technology,p.r.china) Department of Engineering Mechanics Dalian University of Technology China research Institute of Engineering Mechanics Dalian University of Technology China

rotationally periodic symmetry is exploited in 2-D elastostatic calculation using the *** is proved that the coefficient matrices of the global boundary element equations for the rotationally periodic system are block-circulant so long as a kind of symmetry-adapted reference coordinate system is adopted. Furthermore,an efficient algorithm,which partitions the original problem of solving the boundary element equations into a series of subproblems,is *** method permits arbitrary load distribution for stress analysis problems.

关键词： rotationally periodic symmetry boundary element

Discriminative Latent Model Based Chinese Multiword Expression Extraction

在线全文

学校读者我要写书评

暂无评论

china Communications 2012年第3期9卷 124-133页

作者： Xiao, Sun Hefei Univ Technol AnHui Prov Key Lab Affect Comp & Adv Intelligent Hefei 230009 Peoples R China dalian Univ Technol Sch Comp Sci & Technol Dalian 116024 Peoples R China

Discriminative Latent Model(DLM) is proposed for Multiword Expressions(MWEs) extraction in Chinese text to improve the performance of Machine Translation(MT) system such as Template Based MT(TBMT).For MT systems to become of further practical use,they need to be enhanced with MWEs processing *** our study towards this goal,we propose DLM,which is developed for sequence labeling task including hidden structures,to extract MWEs for MT *** combines the advantages of existing discriminative models,which can learn hidden structures in sequence labeling *** our evaluations,DLM achieves precisions ranging up to 90.73% for some type of MWEs,which is higher than state-of-the-art discriminative *** results demonstrate that it is feasible to automatically identify many Chinese MWEs using our DLM *** MWEs processing model,BLEU score of MT system has also been increased by up to 0.3 in close test.

关键词： informationguage processing MT sions processing natural lan-DLM multiword expres-

THE AppLICATION OF COKELET'S WAVE THEOrY IN THE CALCULATION OF WAVE-CUrrENT FIELD

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1993年第2期5卷 45-51页

作者： Li Yu-cheng Teng Bin (dalian University of Technology,dalian 116023,p.r.china)

By using Cokelet's wave theory,the limiting wave height and the relative wave angular frequency in wave-current field were calculated in this *** is indicated by numeri- cal calculation that if the water depth is not too small,the result given by authors'calculation are very close to the results of limiting wave height by Dalrymple(1975)and to the data of rel- ative wave angular frequency by linear wave theory;but if water depth is rather small,there are some discrepancy,

关键词： wave theory wave-current field numerical calculation

THE NUMErICAL prEDICTION OF DEVELOpING TUrBULENT FLOW IN 3-D rECTANGULAr DUCTS

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1990年第1期2卷 48-55页

作者： He Zi-san Ni Han-gen dalian University of Technology,dalian 116024,p.r.china

Comparisons are made between experimental data and numerical predictions based on the k-e turbulent model of low reynolds number applicable to developing turbulent flow in rectangular ducts of arbitrary aspect *** numerical procedure utilizes the separated-layers finite-analytical *** merits of the k-e turbulent model of low reynolds number and the computation procedure are assessed by means of comparison with results,referred to that of the length-scale model and the full-reynolds-stress model used in recent years.

关键词： THE NUMErICAL prEDICTION OF DEVELOpING TUrBULENT FLOW IN 3-D rECTANGULAr DUCTS Flow