检索结果-内蒙古大学图书馆

Factorization of saddle-point matrices in dynamical systems optimization-reusing pivots

LINEAR ALGEBRA AND ITS APPLICATIONS 2019年 566卷 61-85页

作者： Kuratko, Jan Charles Univ Prague Fac Math & Phys Prague Czech Republic Czech Acad Sci Inst Comp Sci Pod Vodarenskou Vezi 271-2 Prague Czech Republic

In this paper we consider the application of direct methods for solving a sequence of saddle-point systems. Our goal is to design a method that reuses information from one factorization and applies it to the next one. In more detail, when we compute the pivoted LDLT factorization we speed up computation by reusing already computed pivots and permutations. We develop our method in the frame of dynamical systems optimization. Experiments show that the method improves efficiency over Bunch-Parlett and Bunch-Kaufman while delivering the same results. (C) 2019 Elsevier Inc. All rights reserved.

关键词： Saddle-point matrix Symmetric indefinite factorization Dynamical systems sequential quadratic programming

来源：评论

学校读者我要写书评

暂无评论

Variational Analysis and sequential quadratic programming Approach for Robotics

引用

Procedia Technology 2012年 4卷 636-640页

作者： Ankit R Patel Mahesh A Patel Dhaval R Vyas Assistant Professor Department of Electrical Engineering L C Institute of TechnologyBhandu Mahesana Gujarat India

sequential quadratic programming (SQP) methods are widely used for solving practical optimization problems, especially in contact mechanics. The general structure of SQP methods is briefly introduced and it is shown how these methods can be adapted to field of Robotics, especially bipedal robot. Numerical results are presented for compass bipedal robot. This paper describes relationship between variational analysis and sequential quadratic programming using discrete mechanics and optimal control for bipedal robot.

关键词： Optimal Control Optimization Lagrangian and Hamiltonian Mechanics Robotics sequential quadratic programming

来源：评论

学校读者我要写书评

暂无评论

Configuration and Parameter Design of Electrified Propulsion Systems for Three-Dimensional Transportation: A Comprehensive Review

引用

Green Energy and Intelligent Transportation 2025年

作者： Yunge Zou Yalian Yang Yuxin Zhang The College of Mechanical and Vehicle Engineering Chongqing University Chongqing 400044 The State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing University Chongqing 400044 China

The design of electrified propulsion systems, including their configuration and parameter layers, is crucial to overall vehicle performance. However, with the electrification of three-dimensional transportation (TDT) (air, ground, and sea) and net-zero emission requirements, new challenges and opportunities arise. The design of propulsion systems for aircraft, marines, and trains is inherently more challenging than that of ground vehicles, due to the significantly larger and more complex propulsions. Therefore, this paper provides a comprehensive review and discussion of the configuration design and parameter optimization methods for electrified propulsion systems. Firstly, four development periods of propulsion design are summarized, and the potential topological design space is analyzed from five aspects: energy storage devices, coupling devices, output types, actuators, and power elements. Then, for the first time, six design stages—configuration representation, comparison and modification, generation, physical layer screening, control layer screening, and configuration-parameter co-optimization—are systematically reviewed and evaluated. Then, the strengths and limitations of each stage are analyzed in detail, and the challenges for the propulsion design for TDT in each stage are discussed. Finally, research challenges and trends are discussed, providing useful inspiration and guidance for advancing the configuration design and sizing optimization of electrified propulsion systems for TDT.

关键词： Electrified vehicles Propulsion design Three-dimensional transportation Dynamic modeling Parameter LP Linear programming AWD All-Wheel-Drive MPC Model Predictive Control BD Bond-graph NNL Neural Network Learning CAV Connected and Automated Vehicle NOx Nitrogen Oxide CV conventional fuel vehicles NVH Noise Vibration and Harshness CVT Continuously Variable Transmission OEM Original Equipment Manufacturer CP Convex programming PG Planetary Gear DC/AC Direct current/alternating current PGT Planetary gear trains DP Dynamic programming (P)HEV (Plug-in) Hybrid Electric Vehicle DRM Dual-rotor motor PMP Pontryagin’s Minimization Principle ECMS Equivalent Consumption Minimization Strategy PAST Powertrain System Analysis Toolkit EERCS efficiency evaluation real-time control strategy PEARS power-weighted efficiency analysis for rapid sizing EMR Energetic Macroscopic Representation POG Power-Oriented Graph EMS Energy Management Strategy PSO Particle Swarm Optimization EREV Extended-Range Electric Vehicle PS Power Split ESS Energy Storage System QP quadratic programming EV Electric Vehicle RB Rule-based EVT Electric Variable Transmission RL Reinforcement Learning FC Fuel Cell R/H/S/P Ring gear/Carrier/Sun gear/Pinion gear FC-FEV Fuel Cell Full-Electric Vehicle SC Super capacitor FG Fixed Gear SERCA slope-weighted energy-based rapid control analysis FL Fuzzy Logic SOC State of Charge GA Genetic Algorithm SP-HEV Series-Parallel Hybrid Electric Vehicle GIS Geographical Information System SQP sequential quadratic programming GPS Global Positioning System TDT Three-dimensional transportation GT Game Theory TTD Track-type dozers (H)ESS (Hybrid) Energy Storage System V2B Vehicle-to-Building HEPS Hybrid electric propulsion system V2G Vehicle-to-Grid ITS Intelligent Transportation System V2H Vehicle-to-Home ICE Internal Combustion Engine V2I Vehicle-to-Infrastructure

来源：评论

学校读者我要写书评

暂无评论

Construction site accident analysis using text mining and natural language processing techniques

引用

AUTOMATION IN CONSTRUCTION 2019年 99卷 238-248页

作者： Zhang, Fan Fleyeh, Hasan Wang, Xinru Lu, Minghui Dalarna Univ Dept Comp Engn S-79188 Falun Sweden Univ Nottingham Ningbo Res Ctr Fluids & Thermal Engn Ningbo 315100 Zhejiang Peoples R China Shanghai Jiao Tong Univ Dept Comp Sci & Engn Shanghai 200030 Peoples R China

Workplace safety is a major concern in many countries. Among various industries, construction sector is identified as the most hazardous work place. Construction accidents not only cause human sufferings but also result in huge financial loss. To prevent reoccurrence of similar accidents in the future and make scientific risk control plans, analysis of accidents is essential. In construction industry, fatality and catastrophe investigation summary reports are available for the past accidents. In this study, text mining and natural language process (NLP) techniques are applied to analyze the construction accident reports. To be more specific, five baseline models, support vector machine (SVM), linear regression (LR), K-nearest neighbor (KNN), decision tree (DT), Naive Bayes (NB) and an ensemble model are proposed to classify the causes of the accidents. Besides, sequential quadratic programming (SQP) algorithm is utilized to optimize weight of each classifier involved in the ensemble model. Experiment results show that the optimized ensemble model outperforms rest models considered in this study in terms of average weighted F1 score. The result also shows that the proposed approach is more robust to cases of low support. Moreover, an unsupervised chunking approach is proposed to extract common objects which cause the accidents based on grammar rules identified in the reports. As harmful objects are one of the major factors leading to construction accidents, identifying such objects is extremely helpful to mitigate potential risks. Certain limitations of the proposed methods are discussed and suggestions and future improvements are provided.

关键词： Construction site accident analysis Machine learning Text mining Natural language processing sequential quadratic programming Optimization

来源：评论

学校读者我要写书评

暂无评论

Experimental research on noninvasive reconstruction of optical parameter fields based on transient radiative transfer equation for diagnosis applications

引用

JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER 2019年 222卷 1-11页

作者： Qi, Hong Zhao, Fang-Zhou Ren, Ya-Tao Qiao, Yao-Bin Wei, Lin-Yang Islam, Md Arafat Ruan, Li-Ming Harbin Inst Technol Sch Energy Sci & Engn Harbin 150001 Heilongjiang Peoples R China

The noninvasive reconstruction of optical parameter fields in participating phantom is investigated experimentally based on the measured time-resolved radiative signals, which are detected by the time-correlated single-photon counting system. The discrete ordinate method is employed to solve the forward transient radiative transfer equation to simulate the time-resolved radiative transfer in the physical phantom exposed to ultra-short pulse laser irradiation. On top of that, the sequential quadratic programming algorithm based on the generalized Gaussian Markov random field is applied to solve the inverse problem. To improve the computational efficiency, an adjoint equation technique is adopted to determine the gradient of objective function. Good agreement was obtained between the predicted optical parameter fields and realistic ones. All the reconstruction results demonstrate that the proposed reconstruction methods are proved to be accurate and efficient experimentally. (C) 2018 Elsevier Ltd. All rights reserved.

关键词： Optical parameter fields reconstruction sequential quadratic programming Time-resolved radiative signals The time-correlated single-photon counting system

来源：评论

学校读者我要写书评

暂无评论

Device-to-Device Communications Underlaying Cellular Networks: To Use Unlicensed Spectrum or Not?

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2019年第9期67卷 6598-6611页

作者： Wu, Fanyi Zhang, Hongliang Di, Boya Wu, Jianjun Song, Lingyang Peking Univ Dept Elect Engn Beijing 100871 Peoples R China

In this paper, we consider device-to-device (D2D) communications as an underlay to cellular networks over both licensed and unlicensed spectrums, where long-term evolution (LTE) users utilize the spectrum orthogonally while D2D users share the spectrum with LTE users. In the system, each LTE and D2D user can access the licensed or unlicensed band for communications. To maximize the total throughput of the system, we leverage stochastic geometry to derive the throughput for each kind of user by modeling the deployment of users as Poisson point processes (PPPs), and investigate the spectrum access problem for these users. Since the problem is NP-hard, we propose a sequential quadratic programming (SQP)-based algorithm to obtain the corresponding suboptimal solutions. Theoretically, we evaluate the system performance by analyzing the throughput regions. Simulation results validate the accuracy of the geometric analysis and verify the effectiveness of the proposed algorithm.

关键词： Device-to-device unlicensed communications spectrum access stochastic geometry sequential quadratic programming

来源：评论

学校读者我要写书评

暂无评论

Filter-Based sequential Radial Basis Function Method for Spacecraft Multidisciplinary Design Optimization

引用

AIAA JOURNAL 2019年第3期57卷 1019-1031页

作者： Shi, Renhe Liu, Li Long, Teng Wu, Yufei Tang, Yifan Beijing Inst Technol Sch Aerosp Engn Beijing 100081 Peoples R China Beijing Inst Technol Key Lab Dynam & Control Flight Vehicle Minist Educ Beijing 100081 Peoples R China

Spacecraft system design is practically a complex multidisciplinary design optimization (MDO) problem. Because of the application of high-fidelity simulation models, the massive computational cost of spacecraft MDO problems becomes a bottleneck and challenging problem in engineering practices. To address the issue, this paper proposes a novel filter-based sequential radial basis function (FSRBF) method for effectively and efficiently solving spacecraft MDO problems. In FSRBF, to handle expensive constraints, a filter is constructed, augmented, and refined based on the concept of Pareto nondomination, which is then combined with a support vector machine (SVM) to construct the filter-based region of interest (FROI) for sequentially bias sampling. During the optimization process, the expensive multidisciplinary analysis process is approximated by RBF metamodels to reduce the computational cost. The RBF metamodels are gradually updated via consecutively sampling within the FROI, which leads the search to rapidly reach the feasible optimum. A number of numerical benchmark problems are used to demonstrate the desirable performance of the proposed FSRBF compared with several alternative methods. In the end, FSRBF is applied to the design of an all-electric GEO satellite and a small Earth observation satellite to illustrate its capability for real-world spacecraft MDO problems. The results show that FSRBF can successfully obtain feasible solutions to improve the design quality of satellite systems. Moreover, the required computational cost of FSRBF is much lower than that of competitive methods, which illustrates the effectiveness and practicality of the proposed FSRBF for solving spacecraft MDO problems.

关键词： Spacecrafts MDO Satellites Earth Observation Satellite Support Vector Machine Spacecraft System sequential quadratic programming Black Box Finite Element Analysis Genetic Algorithm

来源：评论

学校读者我要写书评

暂无评论

Numerical solution of doubly singular nonlinear systems using neural networks-based integrated intelligent computing

引用

NEURAL COMPUTING & APPLICATIONS 2019年第3期31卷 793-812页

作者： Raja, Muhammad Asif Zahoor Mehmood, Jabran Sabir, Zulqurnain Nasab, A. Kazemi Manzar, Muhammad Anwaar COMSATS Inst Informat Technol Dept Elect Engn Attock Campus Attock Pakistan Preston Univ Kohat Dept Math Islamabad Campus Kohat Pakistan Capital Univ Sci & Technol Dept Math Islamabad Pakistan Univ Sains Malaysia Sch Math Sci Gelugor 11800 Penang Malaysia Hamdard Univ Hamdard Inst Engn & Technol Islamabad Pakistan

In this paper, a bio-inspired computational intelligence technique is presented for solving nonlinear doubly singular system using artificial neural networks (ANNs), genetic algorithms (GAs), sequential quadratic programming (SQP) and their hybrid GA-SQP. The power of ANN models is utilized to develop a fitness function for a doubly singular nonlinear system based on approximation theory in the mean square sense. Global search for the parameters of networks is performed with the competency of GAs and later on fine-tuning is conducted through efficient local search by SQP algorithm. The design methodology is evaluated on number of variants for two point doubly singular systems. Comparative studies with standard results validate the correctness of proposed schemes. The consistent correctness of the proposed technique is proven through statistics using different performance indices.

关键词： Singular systems Artificial neural networks Genetic algorithm sequential quadratic programming Integrating computing

来源：评论

学校读者我要写书评

暂无评论

A novel control approach for path tracking of a force-controlled two-wheel-steer four-wheel-drive vehicle

引用

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2019年第6期233卷 1480-1494页

作者： Tan, Qifan Shi, Lingling Katupitiya, Jay Beijing Jiaotong Univ Sch Mech Elect & Control Engn Beijing 100044 Peoples R China Beijing Inst Technol Sch Mech Engn Beijing Peoples R China Univ New South Wales Sch Mech & Mfg Engn Sydney NSW Australia

This paper presents a novel approach for a force-controlled over-actuated two-wheel-steer four-wheel-drive vehicle to achieve accurate path tracking through control allocation. The control algorithm is developed by combining embedded integrator model predictive control and sequential quadratic programming-based control allocation. Based on the offset model presented in this paper, the model predictive control can generate the virtual accelerations. Using these virtual accelerations in control allocation, the actual control inputs are obtained. The proposed method is then used in a simulation to demonstrate its successful implementation in path tracking.

关键词： Autonomous ground vehicle vehicle force control precision path tracking model predictive control sequential quadratic programming

来源：评论

学校读者我要写书评

暂无评论

A novel minimum weight formulation of topology optimization implemented with reanalysis approach

引用

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING 2019年第5期120卷 567-579页

作者： Long, Kai Gu, Chunlu Wang, Xuan Liu, Jie Du, Yixian Chen, Zhuo Saeed, Nouman North China Elect Power Univ State Key Lab Alternate Elect Power Syst Renewabl Beijing 102206 Peoples R China Hefei Univ Technol Coll Civil Engn Hefei Anhui Peoples R China Guangzhou Univ Sch Mech & Elect Engn Ctr Res Leading Technol Special Equipment Guangzhou Guangdong Peoples R China China Three Gorges Univ Coll Mech & Power Engn Yichang Peoples R China

In this paper, we develop an efficient diagonal quadratic optimization formulation for minimum weight design problem subject to multiple constraints. A high-efficiency computational approach of topology optimization is implemented within the framework of approximate reanalysis. The key point of the formulation is the introduction of the reciprocal-type variables. The topology optimization seeking for minimum weight can be transformed as a sequence of quadratic program with separable and strictly positive definite Hessian matrix, thus can be solved by a sequential quadratic programming approach. A modified sensitivity filtering scheme is suggested to remove undesirable checkerboard patterns and mesh dependence. Several typical examples are provided to validate the presented approach. It is observed that the optimized structure can achieve lighter weight than those from the established method by the demonstrative numerical test. Considerable computational savings can be achieved without loss of accuracy of the final design for 3D structure. Moreover, the effects of multiple constraints and upper bound of the allowable compliance upon the optimized designs are investigated by numerical examples.

关键词： approximate reanalysis multigrid preconditioned conjugate gradients preconditioned conjugate gradient sequential quadratic programming topology optimization

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：