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Multi-objective integrated optimization based on evolutionary strategy with a dynamic weighting schedule 被引量:2
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作者 傅武军 朱昌明 叶庆泰 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期204-207,共4页
The evolutionary strategy with a dynamic weighting schedule is proposed to find all the compromised solutions of the multi-objective integrated structure and control optimization problem, where the optimal system perf... The evolutionary strategy with a dynamic weighting schedule is proposed to find all the compromised solutions of the multi-objective integrated structure and control optimization problem, where the optimal system performance and control cost are defined by H2 or H∞ norms. During this optimization process, the weights are varying with the increasing generation instead of fixed values. The proposed strategy together with the linear matrix inequality (LMI) or the Riccati controller design method can find a series of uniformly distributed nondominated solutions in a single run. Therefore, this method can greatly reduce the computation intensity of the integrated optimization problem compared with the weight-based single objective genetic algorithm. Active automotive suspension is adopted as an example to illustrate the effectiveness of the proposed method. 展开更多
关键词 integrated design multi-objective optimization evolutionary strategy dynamic weighting schedule suspension system
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Fast global motion estimation and moving object extraction algorithm in image sequences 被引量:2
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作者 张涛 费树岷 +1 位作者 李晓东 路红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期192-196,共5页
A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of ... A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of translational components. Then in this application, the edge gray horizontal and vertical projections are used as the block matching feature for the motion vectors estimation. The proposed algorithm reduces the motion estimation computations by calculating the onedimensional vectors rather than the two-dimensional ones. Once the global motion is robustly estimated, relatively stationary background can be almost completely eliminated through the inter-frame difference method. To achieve an accurate object extraction result, the higher-order statistics (HOS) algorithm is used to discriminate backgrounds and moving objects. Experimental results validate that the proposed method is an effective way for global motion estimation and object extraction. 展开更多
关键词 global motion estimation edge projection higherorder statistics moving object extraction
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COMPUTER VISUALIZATION OF ELECTROMAGNETIC WAVE INTERACTION WITH STRUCTURES
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作者 余雄庆 杨景佐 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期80-86,共7页
In this paper, a computer visualization approach is proposed for electromagnetic wave interaction with structures by mains of finite difference-time doain method (F-D) and computer graphics. By visualization of FDTD, ... In this paper, a computer visualization approach is proposed for electromagnetic wave interaction with structures by mains of finite difference-time doain method (F-D) and computer graphics. By visualization of FDTD, Phenomena such as wave propagation, penetration through structures, renection and absorption by structures are observed. Visualization of electromagnetic wave interactions with two wing-shaped structures is demonstrated. These examples indicate that the approach describe in the paper offers an effective way for investigating electromagnetic wave phenomena and is helpful to the engineers in controlling radar signature of the targets. 展开更多
关键词 electromagnetic wave scattering finite difference method radar targets computer visualization ANIMATION
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MULTI-OBJECTIVE SHAPE DESIGN IN AERODYNAMICS USING GAME STRATEGY 被引量:1
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作者 唐智礼 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第3期195-199,共5页
Multi-objective optimization for the optimum shape design is introduced in aerodynamics using the Game theory. Based on the control theory, the employed optimizer and the negative feedback are used to implement the co... Multi-objective optimization for the optimum shape design is introduced in aerodynamics using the Game theory. Based on the control theory, the employed optimizer and the negative feedback are used to implement the constraints. All the constraints are satisfied implicitly and automatically in the design. Furthermore,the above methodology is combined with a formulation derived from the Game theory to treat multi-point airfoil optimization. Airfoil shapes are optimized according to various aerodynamics criteria. In the symmetric Nash game, each “player” is responsible for one criterion, and the Nash equilibrium provides a solution to the multipoint optimization. Design results confirm the efficiency of the method. 展开更多
关键词 Game theory multi-objective optimization aerodynamic design constrained optimal control theory
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HYBRID MULTI-OBJECTIVE GRADIENT ALGORITHM FOR INVERSE PLANNING OF IMRT
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作者 李国丽 盛大宁 +3 位作者 王俊椋 景佳 王超 闫冰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第1期97-101,共5页
The intelligent optimization of a multi-objective evolutionary algorithm is combined with a gradient algorithm. The hybrid multi-objective gradient algorithm is framed by the real number. Test functions are used to an... The intelligent optimization of a multi-objective evolutionary algorithm is combined with a gradient algorithm. The hybrid multi-objective gradient algorithm is framed by the real number. Test functions are used to analyze the efficiency of the algorithm. In the simulation case of the water phantom, the algorithm is applied to an inverse planning process of intensity modulated radiation treatment (IMRT). The objective functions of planning target volume (PTV) and normal tissue (NT) are based on the average dose distribution. The obtained intensity profile shows that the hybrid multi-objective gradient algorithm saves the computational time and has good accuracy, thus meeting the requirements of practical applications. 展开更多
关键词 gradient methods inverse planning multi-objective optimization hybrid gradient algorithm
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MOVING OBJECT TRACKING IN DYNAMIC IMAGE SEQUENCE BASED ON ESTIMATION OF MOTION VECTORS OF FEATURE POINTS 被引量:2
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作者 黎宁 周建江 张星星 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期295-300,共6页
An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algor... An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algorithm. The matching points of these feature points are then determined by adaptive rood pattern searching. Based on the random sample consensus (RANSAC) method, the background motion is finally compensated by the parameters of an affine transform of the background motion. With reasonable morphological filtering, the moving objects are completely extracted from the background, and then tracked accurately. Experimental results show that the improved method is successful on the motion background compensation and offers great promise in tracking moving objects of the dynamic image sequence. 展开更多
关键词 motion compensation motion estimation feature extraction moving object tracking dynamic image sequence
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PARETO FRONT CAPTURE USING DETERMINISTIC OPTIMIZATION METHODS IN MULTI-CRITERION AERODYNAMIC DESIGN
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作者 唐智礼 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期81-86,共6页
Deterministic optimization methods are combined with the Pareto front concept to solve multi-criterion design problems. The algorithm and the numerical implementation are applied to aerodynamic designs. Evolutionary a... Deterministic optimization methods are combined with the Pareto front concept to solve multi-criterion design problems. The algorithm and the numerical implementation are applied to aerodynamic designs. Evolutionary algorithms (EAs) and the Pareto front concept are used to solve practical design problems in industry for its robustness in capturing convex, concave, discrete or discontinuous Pareto fronts of multi-objective optimization problems. However, the process is time-consuming. Therefore, deterministic optimization methods are introduced to capture the Pareto front, and the types of the captured Pareto front are explained. Numerical experiments show that the deterministic optimization method is a good alternative to EAs for capturing any convex and some concave Pareto fronts in multi-criterion aerodynamic optimization problems due to its efficiency. 展开更多
关键词 multi-criterion design Pareto front deterministic optimization methods AERODYNAMICS
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Modeling of the Multi-Target Locating and Tracking in the Field Artillery System 被引量:1
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作者 杨国胜 窦丽华 +1 位作者 陈杰 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期14-18,共5页
A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ba... A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ball, an algorithm is put forward for multi sensor multi target data fusion and an optimal solution for state estimation is presented. The simulation results prove the algorithm works well for the multi stationary target locating and the multi moving target tracking under the condition of the sparse target environment. Therefore, this method can be directly applied to the field artillery C 3I system. 展开更多
关键词 field artillery system data fusion closed ball cluster single sensor multi target multi sensor multi target
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Detection technique of moving target based on passive millimeter wave
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作者 李世中 牟春阳 张勇 《Journal of Measurement Science and Instrumentation》 CAS 2014年第4期29-33,共5页
To solve the problem of insufficient ability when detecting the high-speed moving target with passive millimeter wave technology, a direct-detection passive millimeter wave detecting system using the monolithic microw... To solve the problem of insufficient ability when detecting the high-speed moving target with passive millimeter wave technology, a direct-detection passive millimeter wave detecting system using the monolithic microwave integrated cir- cuit (MMIC) millimeter wave radiometer is built, and the measured data are obtained by experiment under different condi- tions. Based on feature analysis of testing signals, it points out that the peak of the first pulse and interval of two peak pulses are valid features which can reflect the motion characteristic of target. A method to calculate the moving speed of target is put forward. The calculating results indicate that the proposed method has enough accuracy and is feasible to determine the parameters of the moving target using for passive millimeter wave system. 展开更多
关键词 passive millimeter wave technology millimeter wave radiometer detection of moving target feature analysis moving speed of target
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Non-contact and Automatic Measurement of 2D Size with CCD Matrix and Computer System 被引量:4
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作者 ZHANG Ye, WANG Wen-sheng, GUO Yang-xue, SONG Hui-ying (College of Photoelectr.Eng.,Changchun University of Science and Technology,Changchun 130022,CHN) 《Semiconductor Photonics and Technology》 CAS 2003年第3期189-192,共4页
A measurement system with the CCD matrix and computer system is designed to test the 2D size of any shape workpieces automatically. In addition, the system adopts the method of the relative measurement which increases... A measurement system with the CCD matrix and computer system is designed to test the 2D size of any shape workpieces automatically. In addition, the system adopts the method of the relative measurement which increases the precision and the velocity.More importantly,the precision cant be changed with the conditions of the temperature and air pressure.The experiments show that the relative precision of 0.002 9 and the absolute precision of 2.97 μm are obtained. The instrument may be used in the product line and make the testing on line possible. 展开更多
关键词 CCD matrix photographic objective COMPUTER
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A meta-analytic review of the approach-avoidance achievement goals and performance relationships in the sport psychology literature 被引量:2
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作者 Marc Lochbaum Jarrett Gottardy 《Journal of Sport and Health Science》 SCIE 2015年第2期164-173,共10页
Purpose: To summarize the approach-avoidance achievement goal and performance in the sport psychology literature.Methods: A total of 17 published studies, two of which provided two samples, were located. Accepted me... Purpose: To summarize the approach-avoidance achievement goal and performance in the sport psychology literature.Methods: A total of 17 published studies, two of which provided two samples, were located. Accepted meta-analytic procedures were used with Hedges g as the effect size metric. From the 17 studies, 73 effect sizes were calculated.Results: Results based on a random effects model indicated that the performance goal contrast had the largest facilitative impact on performance followed by the mastery and performance approach goals. Both of the avoidance goals performance and mastery had small non-significant and detrimental effects on performance. The homogeneity statistics revealed significant heterogeneity for the approach and avoidance performance goals. Categorical moderator variables were examined for study sex composition(male, female, or mixed), mean age of sample(〈18 years or 18 years), study setting(lab or naturalistic), and nature of performance variable(objective or subjective).Conclusion: The performance goal contrast holds value for sport performance research. Contrary to approach-avoidance predictions, the mastery-approach goal and performance effect size was significant and of equal magnitude as the performance approach goal and performance effect size. Thus, future research should closely test the efficacy of both the mastery- and performance contrasts in impacting performance of sport tasks. Last, the significant effect sizes reported in this review are in stark contrast to contemporary meta-analytic findings in education.Differences in the approach-avoidance goals in sport and education relative to performance should be researched further. 展开更多
关键词 Mastery approach goals Performance approach goals Performance enhancement Performance goal contrast
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Decision making tools for optimal material selection:A review 被引量:3
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作者 Divya ZINDANI Saikat Ranjan MAITY Sumit BHOWMIK 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期629-673,共45页
The present work reviews different decision making tools(material comparing and choosing tools)used for selecting the best material considering different parameters.In this review work,the authors have tried to addres... The present work reviews different decision making tools(material comparing and choosing tools)used for selecting the best material considering different parameters.In this review work,the authors have tried to address the following important enquiries:1)the engineering applications addressed by the different material choosing and ranking methods;2)the predominantly used decision making tools addressing the optimal material selection for the engineering applications;3)merits and demerits of decision making tools used;4)the dominantly used criteria or objectives considered while selecting a suitable alternative material;5)overview of DEA on material selection field.The authors have surveyed literatures from different regions of the globe and considered literatures since 1988.The present review not only stresses the importance of material selection in the early design stage of the product development but also aids the design and material engineers to apply different decision making tools systematically. 展开更多
关键词 multi-criteria decision making multi-attribute decision making multi-objective decision making soft computing techniques material selection
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Microphone Array Speech Enhancement Based on Tensor Filtering Methods 被引量:3
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作者 jing wang xiang xie jingming kuang 《China Communications》 SCIE CSCD 2018年第4期141-152,共12页
This paper proposes a novel microphone array speech denoising scheme based on tensor filtering methods including truncated HOSVD(High-Order Singular Value Decomposition), low rank tensor approximation and multi-mode W... This paper proposes a novel microphone array speech denoising scheme based on tensor filtering methods including truncated HOSVD(High-Order Singular Value Decomposition), low rank tensor approximation and multi-mode Wiener filtering. Microphone array speech signal is represented in three-order tensor space with channel, time, and spectrum modes and then tensor filtering model can be designed to process the multiway array data. As to the first method, noise can be reduced through the truncated HOSVD which is a simple scheme in tensor processing. It is more accurate to find the lower-rank approximation of the three-order tensor with Tucker model. Then MDL(Minimum Description Length) criterion is used to estimate the optimal tensor rank in the second method. Further, multimode Wiener filtering approach upon tensor analysis can be considered as the spanning of one-mode wiener filtering. How to take advantages of tensor model to obtain a set of filters is the heart of the novel scheme. The performances of the proposed three approaches are evaluated with objective indexes and listening quality test. The experimental results indicate that the proposed tenor filtering methods have potential ability of retrieving the target signal from noisy microphone array signal and the multi-mode Wiener filtering method provides the best denoising results among the three ones. 展开更多
关键词 speech denoising microphone ar-my tensor filtering truncated HOSVD low rankapproximation multi-mode Wiener filtering
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Design and Implementation of a 3D Ocean Virtual Reality and Visualization Engine 被引量:10
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作者 CHEN Ge LI Bo +2 位作者 TIAN Fenglin JI Pengbo LI Wenqing 《Journal of Ocean University of China》 SCIE CAS 2012年第4期481-487,共7页
In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine applications.The design goals of VV-Ocean aim at high fidelity simulation of ocean environment,... In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine applications.The design goals of VV-Ocean aim at high fidelity simulation of ocean environment,visualization of massive and multidimensional marine data,and imitation of marine lives.VV-Ocean is composed of five modules,i.e.memory management module,resources management module,scene management module,rendering process management module and interaction management module.There are three core functions in VV-Ocean:reconstructing vivid virtual ocean scenes,visualizing real data dynamically in real time,imitating and simulating marine lives intuitively.Based on VV-Ocean,we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface.Environment factors such as ocean current and wind field have been considered in this simulation.On this platform oil spilling process can be abstracted as movements of abundant oil particles.The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering.VV-Ocean can be widely used in ocean applications such as demonstrating marine operations,facilitating maritime communications,developing ocean games,reducing marine hazards,forecasting the weather over oceans,serving marine tourism,and so on.Finally,further technological improvements of VV-Ocean are discussed. 展开更多
关键词 ocean rendering engine virtual reality visualization imitation of marine lives oil spilling simulation
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FAST DETECTING TARGET GROUPS IN SAR IMAGES 被引量:1
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作者 Gao Gui Kuang Gangyao Jiang Yongmei Wang Baosun Gao Sheng 《Journal of Electronics(China)》 2006年第5期781-782,共2页
A successful algorithm for detecting target groups is presented. Firstly, A global Constant False Alarm Rate (CFAR) detector is utilized to locate the potential target regions, and then the features are com- puted for... A successful algorithm for detecting target groups is presented. Firstly, A global Constant False Alarm Rate (CFAR) detector is utilized to locate the potential target regions, and then the features are com- puted for target discrimination based on voting mechanism. Finally, Target groups are extracted. The results of experiments show the validity of this algorithm. 展开更多
关键词 DETECTION DISCRIMINATION LOCATION Target groups
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PERFORMANCE COMPARISON OF A LINEARLY COMBINED ORDERED-STATISTIC DETECTORS UNDER POSTDETECTION INTEGRATION AND NONHOMOGENEOUS SITUATIONS 被引量:2
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作者 Mohamed Bakry El_Mashade 《Journal of Electronics(China)》 2006年第5期698-707,共10页
Several Constant False Alarm Rate (CFAR) architectures, where radar systems often employ them to automatically adapt the detection threshold to the local background noise or clutter power in an attempt to maintain a... Several Constant False Alarm Rate (CFAR) architectures, where radar systems often employ them to automatically adapt the detection threshold to the local background noise or clutter power in an attempt to maintain an approximately constant rate of false alarm, have been recently proposed to estimate the unknown noise power level. Since the Ordered-Statistics (OS) based algorithm has some advantages over the Cell-Averaging (CA) technique, we are concerned here with this type of CFAR detectors. The Linearly Combined Ordered-Statistic (LCOS) processor, which sets threshold by processing a weighted ordered range samples within finite moving window, may actually perform somewhat better than the conventional OS detector. Our objective in this paper is to analyze the LCOS processor along with the conventional OS scheme for the case where the radar receiver incorporates a postdetection integrator amongst its contents and where the operating environments contain a number of secondary interfering targets along with the primary target of concern and the two target types fluctuate in accordance with the Swerling Ⅱ fluctuation model and to compare their performances under various operating conditions. 展开更多
关键词 Constant False Alarm Rate (CFAR) detectors Clutter edges Extraneous targets Postdetection integration Ordered-statistic algorithm
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Linear Track Estimation Using Double Pulse Sources for Near-Field Underwater Moving Target 被引量:2
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作者 Zhifei ChenI Hong Hou +2 位作者 Jianhua Yang Jincai Sun Qian Wang 《Journal of Marine Science and Application》 2013年第2期240-244,共5页
The double pulse sources (DPS) method is presented for linear track estimation in this work. In the field of noise identification of underwater moving target, the Doppler will distort the frequency and amplitude of ... The double pulse sources (DPS) method is presented for linear track estimation in this work. In the field of noise identification of underwater moving target, the Doppler will distort the frequency and amplitude of the radiated noise. To eliminate this, the track estimation is necessary. In the DPS method, we first estimate bearings of two sinusoidal pulse sources installed in the moving target through baseline positioning method. Meanwhile, the emitted and recorded time of each pulse are also acquired. Then the linear track parameters will be achieved based on the geometry pattern with the help of double sources spacing. The simulated results confirm that the DPS improves the performance of the previous double source spacing method. The simulated experiments were carried out using a moving battery car to further evaluate its performance. When the target is 40-60m away, the experiment results show that biases of track azimuth and abeam distance of DPS are under 0.6° and 3.4m, respectively. And the average deviation of estimated velocity is around 0.25m/s. 展开更多
关键词 linear track estimation double pulse sources (DPS) baseline positioning method time-of-arrival difference
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Numerical Analysis of the High Skew Propeller of an Underwater Vehicle 被引量:3
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作者 Hassan Ghasseni Parviz Ghadimi 《Journal of Marine Science and Application》 2011年第3期289-299,共11页
A numerical analysis based on the boundary element method (BEM) was presented for the hydrodynamic performance of a high skew propeller (HSP) which is employed by an underwater vehicle (UV). Since UVs operate at... A numerical analysis based on the boundary element method (BEM) was presented for the hydrodynamic performance of a high skew propeller (HSP) which is employed by an underwater vehicle (UV). Since UVs operate at two different working conditions (surface and submerged conditions), the design of such a propeller is a cumbersome task. This is primarily due to the fact that the resistance forces as well as the vessel efficiency under these conditions are significantly different. Therefbre, some factors are necessary for the design of the optimum propeller to utilize the power at the mentioned conditions. The design objectives of the optimum propeller are to obtain the highest possible thrust, minimum torque, and efficiency. In the current study, a 5-bladed HSP was chosen for running the UV. This propeller operated at the stern of the UV hull where the inflow velocity to the propeller was non-uniform. Some parameters of the propeller were predicted based on the UV geometrical hull and operating conditions. The computed results include the pressure distribution and the hydrodynamic characteristics of the HSP in open water conditions, and comparison of these results with those of the experimental data indicates good agreement. The propeller efficiency for both submerged and surface conditions was found to be 67% and 64%, respectively, which compared to conventional propellers is a significantly higher efficiency. 展开更多
关键词 boundary element method (BEM) hydrodynamic analysis high skew propeller surface andsubmerged conditions
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The General Design and Technology Innovations of CAP1400 被引量:32
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作者 Mingguang Zheng Jinquan Yan +3 位作者 Jun Shenttu Lin Tian Xujia Wang Zhongming Qiu 《Engineering》 SCIE EI 2016年第1期97-102,共6页
The pressurized water reactor CAP1400 is one of the sixteen National Science and Technology Major Projects. Developed from China's nuclear R&D system and manufacturing capability, as well as APIO00 technology introd... The pressurized water reactor CAP1400 is one of the sixteen National Science and Technology Major Projects. Developed from China's nuclear R&D system and manufacturing capability, as well as APIO00 technology introduction and assimilation, CAP1400 is an advanced large passive nuclear power plant with independent intellectual property rights. By discussing the top design principle, main performance objectives, general parameters, safety design, and important improvements in safety, economy, and oth- er advanced features, this paper reveals the technology innovation and competitiveness of CAP1400 as an internationally promising Gen-IIl PWR model. Moreover, the R&D of CAP1400 has greatly promoted China's domestic nuclear power industry from the Gen-II to the Gen-III level. 展开更多
关键词 CAPI400 Advanced passive technology General designLocalizationTechnology INNOVATION
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A Strategy for Multi-objective Optimization under Uncertainty in Chemical Process Design 被引量:4
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作者 孙力 Helen H.Lou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期39-42,共4页
In many circumstances, chemical process design can be formulated as a multi-objective optimization (MOO) problem. Examples include bi-objective optimization problems, where the economic objective is maximized and en... In many circumstances, chemical process design can be formulated as a multi-objective optimization (MOO) problem. Examples include bi-objective optimization problems, where the economic objective is maximized and environmental impact is minimized simultaneously. Moreover, the random behavior in the process,property, market fluctuation, errors in model prediction and so on would affect the performance of a process. Therefore, it is essential to develop a MOO methodology under uncertainty. In this article, the authors propose a generic and systematic optimization methodology for chemical process design under uncertainty. It aims at identifying the optimal design from a number of candidates. The utility of this methodology is demonstrated by a case study based on the design of a condensate treatment unit in an ammonia plant. 展开更多
关键词 multi-objective optimization UNCERTAINTY chemical process design
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