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MINIMIZING A LINEAR FRACTIONAL FUNCTION SUBJECT TO A SYSTEM OF SUP-T EQUATIONS WITH A CONTINUOUS ARCHIMEDEAN TRIANGULAR NORM

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Journal of Systems Science & Complexity 2009年第1期22卷 49-62页

作者： Pingke LI Edward P.Fitts department of Industrial and Systems engineering,North Carolina State {2.,Raleigh,NC 2.695-7906,US Shu-Cherng FANG Edward P.Fitts department of Industrial and Systems engineering,North Carolina State {2.,Raleigh,NC 2.695-7906,USA department of Mathematical Sciences,Tsinghua {2.,Beijing 100084,China College of Management,dalian {2. of technology,dalian {12.,China. Edward P. Fitts department of Industrial and Systems engineering North Carolina State University Raleigh USA department of Mathematical Sciences Tsinghua University Beijing China College of Management Dalian University of Technology Dalian China

This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization problem in polynomial ***,parametrization techniques,e.g.,Dinkelbach's algorithm,can be applied by solving a classical set covering problem in each *** reduction can also be performed on the sup-T equation constrained optimization problems withan objective function being monotone in each variable *** method could be extended aswell to the case in which the triangular norm is non-Archimedean.

关键词： Fractional optimization fuzzy relational equations triangular norms.

Method for Risky Multiobjective Group Decision-Making and Its Application

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Journal of Systems engineering and Electronics 2003年第4期14卷 7-12页

作者： Yu Yibin & Wang Bende department of civil and Hydraulic {2.,{3., dalian 116024, P. R. China department of civil and Hydraulic {2.. Dahan{3. of technology Dalian 116024.P.R. China

The multiobjective group decision-making problem under risk is common in reality. This paper focuses on the study about risky multiobjective group decision-making problem where the index value is not certain. We give indexes classifying method and index normalizing formula of this type problem. By building objective function that minimizes general weighted distance from every alternative to the relatively best and worst alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, and by building another objective function that minimizes general weighted distance from the optimal membership degree of every decision-maker to every alternative to the group optimal alternative and the group inferior alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, which are both based on probability theory and fuzzy theory. Aftermost a model is established which collects group preferences. This method provides a new idea and approach for solving multiobjective decision-making problem among uncertain system, which is applicable for practical problem. Finally a case study shows a satisfactory result.

关键词： multiobjective decision-making risk probability relative optimal membership degree weights.

The Antifreeze Critical Strength of Low-temperature Concrete Effected by Index

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Journal of Wuhan university of technology(Materials Science) 2011年第2期26卷 355-360页

作者：刘军 School of Material Science and engineering Shenyang Jianzhu University

The antifreeze critical strength and the pre-curing time of low-temperature concrete were studied by means of guaranteed rate of compressive strength and antifreeze performance for the structural safety requirement of concrete engineering,suffering once freeze damage under air *** is shown that the antifreeze critical strength is 3.7-4.4MPa,pre-curing time is 18-3.1}h by guaranteed rate of compressive strength,and the antifreeze critical strength is 3.7-4.4MPa,pre-curing time is 18-3.1}h by guaranteed rate of antifreeze *** can be found that the method of guaranteed rate of compressive strength is sensitive to the defect which generated by freeze damage in the concrete *** method is fit to evaluate the antifreeze critical strength of low-temperature concrete.

关键词： guaranteed rate of compressive strength guaranteed rate of antifreeze performance antifreeze critical strength once freeze under air environment

Large eddy simulation of fuel injection and mixing process in a diesel engine

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Acta Mechanica Sinica 2011年第4期27卷 519-530页

作者： Lei Zhou.Mao-Zhao Xie.Ming Jia.Jun-Rui Shi School of Energy and Power engineering,dalian {2. of{3.,116024 dalian,China department of Power engineering,Shenyang Institute of engineering,11013. Shenyang,China School of Energy and Power engineering Dalian University of Technology Dalian China department of Power engineering Shenyang Institute of Engineering Shenyang China

The large eddy simulation （LES） approach implemented in the KIVA-3. code and based on one-equation sub-grid turbulent kinetic energy model are employed for numerical computation of diesel sprays in a constant volume vessel and in a Caterpillar 3.00 series diesel engine. Computational results are compared with those obtained by an RANS （RNG k-e） model as well as with experimental data. The sensitivity of the LES results to mesh resolution is also discussed. The results show that LES generally provides flow and spray characteristics in better agreement with experimental data than RANS; and that small-scale random vortical structures of the in-cylinder turbulent spray field can be captured by LES. Furthermore, the penetrations of fuel droplets and vapors calculated by LES are larger than the RANS result, and the sub-grid turbulent kinetic energy and sub-grid turbulent viscosity provided by the LES model are evidently less than those calculated by the RANS model. Finally, it is found that the initial swirl significantly affects the spray penetration and the distribution of fuel vapor within the combustion chamber.

关键词： Large eddy simulation Diesel engine Fuelspray

DEVELOPMENT AND APPLICATION OF A EUTROPHICATION WATER QUALITY MODEL FOR RIVER NETWORKS

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Journal of Hydrodynamics 2008年第6期20卷 719-726页

作者： ZHANG Ming-liang SHEN Yong-ming GUO Yakun State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116023 China department of civil and Structural {2. The Hong Kong Polytechnic University Hong Kong China department of engineering University of Aberdeen Aberdeen AB24 3UE UK

The Preissmann implicit scheme was used to discretize the one-dimensional Saint-Venant equations, the river-junction-fiver method was applied to resolve the hydrodynamic and water quality model for river networks, and the key issues on the model were expatiated particularly in this article. This water quality module was designed to compute time dependent concentrations of a series of constituents, which are primarily governed by the processes of advection, dispersion and chemical reactions. Based on the theory of Water Quality Analysis Simulation Program （WASP） water quality model, emphasis was given to the simulation of the biogeochemical transformations that determine the fate of nutrients, in particular, the simulation of the aquatic cycles of nitrogen and phosphorus compounds. This model also includes procedures for the determination of growth and death of phytoplankton. This hydrodynamic and water quality model was applied to calculate two river networks. As illustrated by the numerical examples, the calculated water level and discharge agree with the measured data and the simulated trends and magnitudes of water quality constituents are generally in good agreement with field observations. It is concluded that the presented model is useful in the pollutant control and in the determination of pollutant-related problems for river networks.

关键词： Preissmann implicit scheme river networks hydrodynamic model water quality model biogeochemical transformations three-step method

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. department of Marine Environmental {3., {2. Maritime {3., {2. 11602., China E mail: deqi@*** 2. department of Environmental {3., SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

Nonlinear Wave Force on Pier Group in Shallow Water

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China Ocean engineering 1992年第1期7卷 1-18页

作者： Qiu Dahong , Zhou Yuanheng and Jia Ying Professor, Dept. of civil engineering,{2.,{3. Lecturer, Dept. of civil engineering,{2.,{3.

Based on the 1st order cnoidal wave theory, the wave diffraction around the pier group inshallow water is studied in this paper. The formulas for calculating the nonlinear wave forces are also presented here. In order to verify the theoretical results, model tests are conducted in the wave flume in The State Key Laboratory of Coastal and Offshore engineering located in dalian university of technology. The range of the wave parameters in the experiments is characteristic wave period T g/d^(1/2. = 8.08- 2..86, characteristic wave height H/ d= 0.1 ~ 0.45. The results obtained from the experiments agree with the theoretical results quite well. It is shown that, in shallow water the nonlinear wave forces acting on a pier group are greater than those calculated by linear wave theory, the value of increment in wave force increases with the increases of the nonlinearity of the wave. In the wave range studied in this paper, the nonlinear wave force can reach over 4 times the force calculatecd by linear wave theory. Thus, it is suggested that, when Tg / d^(1/2.> 8, the wave force on the piers in the pier group in shallow water should be calculated by using the cnoidal wave theory.

关键词： cylinder pier group wave force shallow water model test

Dynamic and Seismic Property Experiments of High Damping Concrete and Its Frame Models

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Journal of Wuhan university of technology(Materials Science) 2008年第1期23卷 1-6页

作者：欧进萍刘铁军 LI Jilong Shenzhen Graduate School of Harbin Institute of technology Shenzhen 518055 China School of civil ＆ Hydraulic engineering Dalian University of Technology Dalian 116024 China School of civil engineering Harbin Institute of Technology Harbin 150006 China

The loss tangent and storage modulus of cement mortar containing treated silica fume and styrene-acrylic are measured. Shaking table tests on three groups of 1/4 models of high damping concrete frames are conducted to compare the effects of reducing vibration. A relationship between the viscosity coefficient of high damping concrete and the damping coefficient of structure is established by analyzing dynamic parameters like damping ratio and frequency, and comparing responses of relative displacement and absolute acceleration. Surface treatment of silica fume and styrene-acrylic emulsion prior to incorporation in a cement mortar increases the loss tangent of the resulting composite by 40-400% as compared to the cement mortar without any admixtures, and the damping ratio of the reinforced concrete is raised by 7%-9%. In addition, a theoretical method of determining the viscosity coefficient of the material on the basis of shaking table test results is put forward.

关键词： high damping concrete damping relationship seismic experiment surface modification viscosity coefficient

TRANSVERSE FORCES AND RESULTANT FORCES ON ARRAY OF BI-PILE IN IRREGULAR WAVES

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China Ocean engineering 1990年第1期5卷 29-41页

作者： Yu Yuxiu and Zhang Ningchuan Professer, civil Engi. Dept., dalian university of technology, {2. Lecture, civil Engi. Dept., {2. Vniversity of technology, {2. civil Eng Dept Dalian Univ of Tech Dalian China China

The total transverse forces on each of the two piles in the side-by-side arrangement and tandem arrangement are experimentally investigated in irregular waves and the total in-line wave forces are measured simultaneously. The statistical and spectral characteristics of the transverse forces are analyzed. The ratio of the transverse force on each pile in group to that on a single pile is defined as the transverse groupling-pile factor, KGL. Both the transverse coefficients CLG and KGL for each pile in array are varied with the relative pile distance and KC number and their relationships are presented in this paper. Also the ratio of the resultant wave froce of in-line force and transverse force to the in-line force and the vriation of the resultant coefficient are investigated.

关键词： TRANSVERSE FORCES AND RESULTANT FORCES ON ARRAY OF BI-PILE IN IRREGULAR WAVES BI