检索结果-内蒙古大学图书馆

17th International Radar Symposium (IRS)

作者： Tan, U. Rabaste, O. Adnet, C. Arlery, F. Ovarlez, J. -P. Thales Air Syst F-91470 Limours France SONDRA CentraleSupelec F-91192 Gif Sur Yvette France Off Natl Etud & Rech Aerosp French Aerosp Lab F-91123 Palaiseau France

ISBN: (纸本)9781509025183

In this paper, a discussion is made on the optimization methods that can solve the low autocorrelation sidelobes problem for polyphase sequences. This paper starts with a description and a comparison of two algorithms that are commonly used in the literature: a stochastic method and a deterministic one (a gradient descent). Then, an alternative method based on the Random Walk Metropolis-Hastings algorithm is proposed, that takes the gradient as a search direction. It provides better results than a steepest descent alone. Finally, this autocorrelation question is handled differently, considering a mismatched tiller. We will see that a mismatched filter performs impressively well on optimized sequences.

关键词： Aperiodie autocorrelation optimization algorithms Gradient descent Mismatched filter

来源：评论

学校读者我要写书评

暂无评论

World Competitive Contests (WCC) algorithm: A novel intelligent optimization algorithm for biological and non-biological problems

引用

Informatics in Medicine Unlocked 2016年 3卷 15-28页

作者： Masoudi-Sobhanzadeh, Yosef Motieghader, Habib Department of Computer Engineering Payam Noor University Tabriz Iran Laboratory of Systems Biology and Bioinformatics (LBB) Institute of Biochemistry and Biophysics University of Tehran Tehran Iran

Since different sciences face lots of problems which cannot be solved in reasonable time order, we need new methods and algorithms for getting acceptable answers in proper time order. In the present study, a novel intelligent optimization algorithm, known as WCC (World Competitive Contests), has been proposed and applied to find the transcriptional factor binding sites (TFBS) and eight benchmark functions discovery processes. We recognize the need to introduce an intelligent optimization algorithm because the TFBS discovery is a biological and an NP-Hard problem. Although there are some intelligent algorithms for the purpose of solving the above-mentioned problems, an optimization algorithm with good and acceptable performance, which is based on the real parameters, is essential. Like the other optimization algorithms, the proposed algorithm starts with the first population of teams. After teams are put into different groups, they will begin competing against their rival teams. The highly qualified teams will ascend to the elimination stage and will play each other in the next rounds. The other teams will wait for a new season to start. In this paper, we're going to implement our proposed algorithm and compare it with five famous optimization algorithms from the perspective of the following: the obtained results, stability, convergence, standard deviation and elapsed time, which are applied to the real and randomly created datasets with different motif sizes. According to our obtained results, in many cases, the WCC׳s performance is better than the other algorithms’. © 2016

关键词： optimization algorithms The motif discovery Transcriptional factor binding sites World Competitive Contests

来源：评论

学校读者我要写书评

暂无评论

optimization OF REINFORCING RIBS OF A HOLLOW FAN BLADE USING METAMODEL-BASED optimization ALGORITHM

OPTIMIZATION OF REINFORCING RIBS OF A HOLLOW FAN BLADE USING...

引用

ASME Turbo Expo: Turbine Technical Conference and Exposition

作者： Ma, Ying Xu, Shengli Liu, Haitao Wang, Xiaofang Dalian Univ Technol Sch Energy & Power Engn Dalian Liaoning Peoples R China

ISBN: (纸本)9780791849712

With the development of aero-engine technology, the demand for fan blade with light weight and better structural performances is urgent. This paper focuses on the weight optimization of a hollow fan blade through changing the thickness and distribution of the inner triangular reinforcing ribs under the constraints of equivalent stress, displacement, bending and torsional frequencies. A fmite element analysis process was established in the paper, considering the load of centrifugal force and gas pressure. In the CAD-based model parameterization, to avoid possible interference problems brought by design parameters, the relative locations of control points are applied to determine the locations of control points on the vane profile curves. A metamodel-based global optimization scheme is employed for improving the optimization efficiency. An optimal design with about 13.7% weight reduction is finally obtained by the above optimization procedure. The triangular reinforcing ribs of hollow fan blade were rearranged with the constraints of the stress, displacement and natural frequencies satisfied.

关键词： Aircraft engines Stress Finite element analysis Weight (Mass) Centrifugal force Pressure optimization Design Displacement optimization algorithms Blades Computer-aided design

来源：评论

学校读者我要写书评

暂无评论

optimization ALGORITHM COMPARISON FOR IN-PLANE FLEXIBLE RING TIRE MODEL PARAMETER IDENTIFICATION

OPTIMIZATION ALGORITHM COMPARISON FOR IN-PLANE FLEXIBLE RING...

引用

ASME International Design Engineering Technical Conference / Computer and Information in Engineering Conference (IDETC/CIE)

作者： Li, Bin Yang, Xiaobo Yang, James Zhang, Yunqing Ma, Zeyu Texas Tech Univ Dept Mech Engn Lubbock TX 79409 USA Oshkosh Corp Oshkosh WI USA Huazhong Univ Sci & Technol Wuhan Hubei Peoples R China

ISBN: (纸本)9780791850138

The parameter values used in a tire model directly determine the prediction accuracy of the model. Poorly identified parameters lead to incorrect prediction of tire performances. The optimization algorithm used for parameter identification has a huge impact on the quality of the identified parameters for a tire model. In this paper, four different optimization algorithms in MATLAB, including local optimization algorithms (fiminsearchcon and patternsearch) and global optimization algorithms (particleswarm and GA-genetic algorithm), are applied to identify the parameters of a newly proposed in-plane flexible ring tire model based on one cleat experiment results, respectively. Their performances are compared in terms of the prediction accuracy, efficiency and some other aspects. After the comparison, the most suitable optimization algorithm for tire model parameter identification is obtained. Finally, the parameters that are identified based on the set of parameters from the most suitable algorithm are used to predict the other cleat test conditions to further validate the tire model.

关键词： Flexible ring tire model parameter identification optimization algorithms vehicle performance and cleat test

来源：评论

学校读者我要写书评

暂无评论

ROBUST DESIGN optimization BY ADAPTIVE-SPARSE POLYNOMIAL DIMENSIONAL DECOMPOSITION

ROBUST DESIGN OPTIMIZATION BY ADAPTIVE-SPARSE POLYNOMIAL DIM...

引用

ASME International Design Engineering Technical Conference / Computer and Information in Engineering Conference (IDETC/CIE)

作者： Ren, Xuchun Rahman, Sharif Georgia Southern Univ Dept Mech Engn Statesboro GA 30458 USA Univ Iowa Dept Mech Engn Iowa City IA 52242 USA

ISBN: (纸本)9780791850084

This work proposes a new methodology for robust design optimization (RDO) of complex engineering systems. The method, capable of solving large-scale RDO problems, involves (1) an adaptive-sparse polynomial dimensional decomposition (AS-PDD) for stochastic moment analysis of a high-dimensional stochastic response, (2) a novel integration of score functions and AS-PDD for design sensitivity analysis, and (3) a multi-point design process, facilitating standard gradient-based optimization algorithms. Closed-form formulae are developed for first two moments and their design sensitivities. The method allow that both the stochastic moments and their design sensitivities can be concurrently determined from a single stochastic simulation or analysis. Precisely for this reason, the multi-point framework of the proposed method affords the ability of solving industrial scale problems with large design spaces. The robust shape optimization of a three-hole bracket was accomplished, demonstrating the efficiency of the new method to solve industry-scale RDO problems.

关键词： optimization Engineering systems and industry applications Space Shape optimization Simulation Design sensitivity analysis Design Polynomials optimization algorithms

来源：评论

学校读者我要写书评

暂无评论

optimization OF AN ELECTROMAGNETIC ENERGY HARVESTING BACKPACK UNDER ACTUAL WALKING AND RUNNING SCENARIOS

引用

ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems

作者： Mullen, Christopher Lee, Soobum Univ Maryland Baltimore Cty Dept Mech Engn Baltimore MD 21250 USA

ISBN: (纸本)9780791850497

Energy harvesting technology can provide a renewable, portable power source for soldiers who rely solely on battery power in the field. Electromagnetic energy harvesters scavenge energy from wasted kinematic and vibration energy in human motion. The motion of interest in this paper is vertical hip displacement during human gait that acts as a base excitation. The placement of a permanent magnet based linear generator mounted in a backpack can make use of this excitation that results in relative motion of the magnet to the coil of copper wire, which induces an electric current. This current can be used to charge a battery or capacitor bank installed on the backpack to power portable electronic devices, thereby reducing the need for extra batteries and overall battery weight. The purpose of this research is to use a multi-variable optimization algorithm to identify an optimal coil and magnet layout for power maximization. Results from this study will pave the way for a more efficient energy harvesting backpack while providing better insight into the efficiency of magnet and coil layout for various applications for electromagnetic power generation from vibration.

关键词： Electromagnetic radiation Batteries Generators Energy harvesting Displacement Excitation Kinematics optimization Vibration Copper Permanent magnets Weight (Mass) Energy generation Wire Capacitors optimization algorithms Soldiers Magnets Electric current

来源：评论

学校读者我要写书评

暂无评论

Teaching-Learning-Based optimization with Two-Stage Initialization

Teaching-Learning-Based Optimization with Two-Stage Initiali...

引用

IEEE Students Conference on Electrical, Electronics and Computer Science (SCEECS)

作者： Puralachetty, Manasa Madhavi Gondela, Lakshmi Manasa Pamula, Vinay Kumar Akula, Venkata Naresh Babu JNTUK UCEK Dept ECE Kakinada 533003 India MIC Coll Technol Dept EEE Kanchikacherla 521180 India

ISBN: (纸本)9781467379182

The teaching-learning-based optimization (TLBO) algorithm is an evolutionary algorithm based on simulated teaching-learning procedure in a class. This algorithm requires no controlling parameters and is moulded based on the effect of influence of teacher on the output of learners and hence can be implemented easily and also requires less computational memory compared to other evolutionary algorithms. This paper presents the (TLBO) algorithm with two-stage initialization (TSI). The TLBO with TSI (TLBO-TSI) is tested with the Rastrigin benchmark function and then used to minimize least-squares (LS), Huber (HU) and Hampel (HA) cost functions. Simulation results are presented to show the evolutionary behavior of the TLBO with TSI. Simulation results show that the TLBO-TSI performs better compared to existing TLBO.

关键词： least-squares optimization algorithms teaching-learning-based optimization

来源：评论

学校读者我要写书评

暂无评论

optimization of low-head hydropower recovery in water supply networks

Optimization of low-head hydropower recovery in water supply...

引用

作者： Irene ALMEIDA SAMORA ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE

学位级别：博士

Small scale hydropower is emerging as a decentralized source to satisfy local demand for electricity. The interest in micro hydropower, which refers to installed power below 100 kW, is increasing since this is a solution with low environmental impact. Water supply systems are one of the main manmade water systems presenting potential for micro hydropower. Although some applications already exist in adduction lines, the urban distribution networks remain unexplored. Because these are complex systems in which flows and pressure vary constantly, specific technology and installation schemes for energy recovery are lacking. This work assesses the potential for hydropower within water supply networks (WSN) and presents an arrangement of micro turbines specially conceived for this type of installation. The arrangement is based on a novel inline turbine suitable for pressurized systems and its best location within the networks is studied. The five blade tubular propeller (5BTP), preliminarily designed in the framework of the European Project HYLOW, was further developed and tested in this work. An experimental campaign was conducted with a large range of heads and torque measurements to assess its characteristic curves and to obtain hill charts. The relative positioning of the turbine generator shaft regarding the pipe bend was modified from a downstream position to an upstream position. Efficiencies of around 60% were found. The adequate locations in WSN for micro hydropower plants are identified using an optimization algorithm which considers both the assessment of the energy production and sizing of the main equipment and works. A concept for the implementation of the 5BTP in the field was developed, consisting of an arrangement with up to four turbines inline within a buried chamber created around an existing pipe. Two objective functions, energy production and economic value respectively, are used. A simulated annealing process is developed to optimize the location of

关键词： Micro hydropower Micro propeller turbine Water supply networks optimization algorithms Energy potential

来源：评论

学校读者我要写书评

暂无评论

Application of In-Test Model Updating to Earthquake Structural Assessment

引用

JOURNAL OF EARTHQUAKE ENGINEERING 2016年第1期20卷 62-79页

作者： Elanwar, Hazem H. Elnashai, Amr S. Univ Illinois Urbana IL USA Cairo Univ Fac Engn Cairo Egypt Penn State Univ Dept Civil & Environm Engn University Pk PA 16802 USA

Analytical methods are frequently utilized for structural assessment due to their simplicity and cost-effectiveness. However, modeling of material inelasticity and geometric nonlinearity under reversed inelastic deformations is still very challenging and its accuracy is difficult to quantify. On the other hand, realistic experimental assessment is costly, time-consuming, and impractical for large or spatially extended structures. Hybrid simulation has been developed as an approach that combines the realism of experimental techniques with the economy of analytical tools. In hybrid simulation, the structural is divided into several modules such that the critical components are tested in the laboratory, while the rest of the structure is simulated numerically. The equations of motion solved in the computer enable the integration of the analytical and experimental components at each time increment. The objective of this article is to apply a newly developed identification and model updating scheme to acquire the material constitutive relationship from the physically tested specimen during the analysis to two complex hybrid simulation case studies. The identification scheme is developed and verified in a companion article, while the two experiments presented in this article are selected such that they address different structural engineering applications. First, a beam-column steel connection with heat treated beam section is analyzed. Afterwards, the response of a multi-bay concrete bridge is investigated. The results of these two examples demonstrate the effectiveness of model updating to improve the numerical model response as compared to the conventional hybrid simulation approaches.

关键词： Model Updating Pseudo-Dynamic Tests Hybrid Simulations Constitutive Relationships optimization algorithms

来源：评论

学校读者我要写书评

暂无评论

A Vibration Reliability Analysis Method for the Uncertain Space Beam Structure

引用

SHOCK AND VIBRATION 2016年第Pt.3期2016卷 1-15页

作者： Mo, Yanyu Guo, Shuxiang Tang, Cheng Air Force Engn Univ Aeronaut & Astronaut Engn Coll Xian 710038 Peoples R China Air Force Engn Univ Coll Sci Xian 710051 Peoples R China

Considering that uncertainty is inherent and unavoidable in engineering practice and the available information about the uncertain parameters is always not sufficient, the paper tries to carry out the nonprobabilistic vibration reliability analysis so as to avoid resonance on uncertain structure with bounded parameters. The input uncertain-but-bounded parameters are treated as interval variables, and an interval model is adopted to describe bounded uncertainties. Then a theory of nonprobabilistic reliability is introduced, in which the dimensionless nonprobabilistic reliability index and system reliability index are defined. In order to investigate the resonance failure with reliability method, the resonance failure domains are stated according to the relationships between the natural frequencies and the excitation frequencies. Then the uncertain structure is modeled as a series system and a system reliability index is proposed to evaluate the safety of the structure. The paper also takes a frequency analysis on the uncertain space beam structure to get the resonance failure modes. A frequency analysis method based on the monotonicity discriminant of the frequency sensitivity is presented. Then an optimization algorithm is introduced to verify the validity of the former frequency analysis method. Two examples are provided to illustrate the effectiveness and feasibility of the presented method.

关键词： Uncertainty Beam structures frequency sensitivity Vibration RESONANCE Plant uncertain series system Frequency analysis Reliability analysis Engineering Practice optimization algorithms reliability index Interval models

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：