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Multi-objective optimisation of a permanent magnet flux-switching motor by combined parameter sensitivities analysis with non-linear varying-network magnetic circuit method

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IET ELECTRIC POWER APPLICATIONS 2019年第1期13卷 24-30页

作者： Zhu, Xiaoyong Jian, Yanhong Xiang, Zixuan Fan, Deyang Yang, Minjian Jiangsu Univ Sch Elect & Informat Engn Zhenjiang Peoples R China Jiangsu Univ Jiangsu Key Lab Drive & Intelligent Control Elect Zhenjiang Peoples R China

In this study, a new sensitivity analysis based on non-linear varying-network magnetic circuit (VNMC) method is proposed for an outer-rotor I-shaped permanent magnet flux-switching motor. By integrating concept of sensitivity analysis into the non-linear VNMC method, the whole design efficiency can be improved effectively by using the comprehensive sensitivity method and sequential non-linear programming algorithm. In the optimisation process, two design objectives are selected, including machine output torque and torque ripple. Based on the sensitivity analysis, the parameters possessing the significant influence on the design objectives can be selected purposely, thus the overall amount of calculation is obviously reduced. After the determination of the sensitive parameters, the rest of optimisation can be realised efficiently by the non-linear VNMC method. Finally, a prototype motor is manufactured and tested. Both theoretical analysis and experimental results confirm the effectiveness of the proposed method.

关键词： magnetic circuits Optimisation techniques nonlinear VNMC method theoretical analysis nonlinear programming algorithm machine output torque magnetic flux nonlinear varying-network magnetic circuit method design efficiency sensitivity analysis sensitive parameter determination torque permanent magnet motors comprehensive sensitivity method optimisation process Other electromagnetic device applications design objectives multiobjective optimisation outer-rotor I-shaped permanent magnet flux-switching motor nonlinear programming combined parameter sensitivity analysis torque ripple a.c. machines rotors

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Stabilizer control design for nonlinear systems based on the hyperbolic modelling

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APPLIED MATHEMATICAL MODELLING 2019年 67卷 413-429页

作者： Skandari, M. H. Noori Ghaznavi, M. Abedian, M. Shahrood Univ Technol Fac Math Sci Shahrood Iran

In this paper, a new approach to design a stabilizer control for nonlinear systems is presented. First, the general form of the nonlinear control systems is approximated with a hyperbolic model. Then, by a feedback technique, a stabilizer control for the hyperbolic system is obtained. It is shown that this control can stabilize the original nonlinear control system. Finally, by some illustrative examples, the efficiency of the presented approach is demonstrated. (C) 2018 Elsevier Inc. All rights reserved.

关键词： nonlinear control system Hyperbolic system Stabilizer control nonlinear programming

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Carbon emissions reduction in China's container terminals: Optimal strategy formulation and the influence of carbon emissions trading

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JOURNAL OF CLEANER PRODUCTION 2019年 219卷 518-530页

作者： Zhong, Huiling Hu, Ziwei Yip, Tsz Leung South China Univ Technol Sch Econ & Commerce Dept Logist Engn Guangzhou Guangdong Peoples R China Hong Kong Polytech Univ Dept Logist & Maritime Studies Hung Hom Kowloon Hong Kong Peoples R China

To reduce CO2 emissions, the Chinese government has established a carbon emissions trading scheme, with industrial enterprises being allocated free emissions quotas and buying permits on the carbon market for over-quota emissions. Enterprises, including container terminals, must also progressively reduce their carbon emissions intensities and will be affected by the costs associated with reducing emissions as well as by carbon trading expenses. Therefore, in this study, the costs of carbon reduction (e.g., equipment changes, management interventions, and carbon trading) are calculated, and a nonlinear programming model is developed to formulate an optimal strategy of measures for a terminal enterprise to meet its statutory emissions-reduction target while minimizing the associated expenditure. In addition, the specific effect of carbon trading (using the free emissions quota percentage or FEQP and the carbon trading price or CTP) on a terminal's optimal emissions-reduction strategy is examined. Using the case of Nansha terminal over a five-year period, the model results show that under the current FEQP and CTP, the carbon trading expenses constitute only 0.1% of the total expenditure on carbon-reduction measures. Therefore, the current values of the FEQP and CTP provide very little incentive for terminals to reduce emissions. Sensitivity analysis shows that under a decreasing FEQP, the terminal's expenses increase linearly but the emissions amount decreases stepwise. An increase in the CTP from 40 to 190 Yuan/t increases the terminal's expenses linearly and decreases its emissions stepwise, but emissions show no further decrease for a CTP of 190-370 Yuan/t. The findings have implications for policy-making as well as for terminals' carbon-reduction strategies and costs. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： nonlinear programming Equipment energy transformation Equipment replacement Container terminal Carbon emissions reduction Carbon trading market

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Data gathering maximisation for wireless sensor networks with a mobile sink

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INTERNATIONAL JOURNAL OF AD HOC AND UBIQUITOUS COMPUTING 2019年第4期32卷 224-235页

作者： Han, Zongyuan Shi, Tianyun Lv, Xiaojun Jia, Xinchun Wang, Zhongying Zhou, Dong China Acad Railway Sci Inst Comp Technol Beijing 100081 Peoples R China Shanxi Univ Sch Math Sci Taiyuan 030006 Peoples R China

Recent studies have demonstrated that the significant benefit can be achieved by using mobile sinks for data gathering in wireless sensor networks (WSNs). However, most of them employed a typical scheme that the mobile collector pauses at the anchor points on its moving tour for a period time to collect the data from nearby sensors. In this paper, the data gathering process is divided into two stages named parking communication (PC) and moving communication (MC). We focus on maximising the total amount of data gathering by the mobile sink, and formulate the problem as two different optimisation models under several constraints for these two different communication stages. Accordingly, dual decomposition and simplex methods are dexterously exploited to derive the optimal communication time and flow rates allocation schemes. Computational results demonstrate the efficiency of the proposed algorithms.

关键词： wireless sensor network WSN mobile data gathering dual decomposition nonlinear programming

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Insights into conditioning of landfill sludge by FeCl3 and lime

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WATER RESEARCH 2019年 160卷 167-177页

作者： Wu, Wei Zhou, Zhen Yang, Jiazhe Chen, Guang Yao, Jie Tu, Chengqin Zhao, Xiaodan Qiu, Zhan Wu, Zhichao Shanghai Univ Elect Power Coll Environm & Chem Engn Shanghai 200090 Peoples R China Shanghai Chengtou Wastewater Treatment Co Ltd Shanghai 201203 Peoples R China Shanghai Inst Pollut Control & Ecol Secur Shanghai 200092 Peoples R China Tongji Univ Coll Environm Sci & Engn State Key Lab Pollut Control & Resource Reuse Shanghai 200092 Peoples R China

In this study, landfill sludge (LS) was excavated from a 10 year old full-scale sludge landfill and used to investigate effects of dosage on sludge dewaterability, rheological properties and extracellular polymeric substances (EPS) variations by FeCl3-lime conditioning. LS had lower content of organic matters (0.28) and smaller particle size than excess sludge (ES), and greatly lower viscosity and high flowability. The suitable concentration of LS for conditioning (107.2-118.6 g/L) was much higher than that of ES (34 g/L) by rheological analysis. Both FeCl3 and lime improved dewaterability of LS and caused decline of slime and loosely bound EPS (LB-EPS). FeCl3 destroyed proteins in slime and LB-EPS owing to coagulation and acidification effects, weakened internal structure strength, and thus improved dewaterability. Lime addition caused alkaline hydrolysis of polysaccharides in slime and LB-EPS, reduced viscosity and flowability, and improved flowability and dewaterability for LS. The optimal dosage for dewatering using 57.6 mg lime/g dried solids (DS) and 53.6 mg FeCl3/g DS was obtained by using an integrative response surface methodology (RSM) coupled nonlinear programming approach under water content constraint of 55%. The integrative optimization achieved 26.0% cost saving in comparison to RSM optimized condition. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Landfill Sludge conditioning Rheology Response surface methodology nonlinear programming Lime FeCl3

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Optimal allocation of distributed generation for planning master-slave controlled microgrids

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IET GENERATION TRANSMISSION & DISTRIBUTION 2019年第16期13卷 3704-3712页

作者： Pasha, Aisha M. Zeineldin, Hatem H. El-Saadany, Ehab F. Alkaabi, Sultan S. Khalifa Univ Dept Elect & Comp Engn Abu Dhabi U Arab Emirates Cairo Univ Fac Engn Dept Elect Power & Machines Giza 12316 Egypt Univ Waterloo ECE Dept Waterloo ON Canada Al Ain Distribut Co Abu Dhabi Water & Elect Author Al Ain U Arab Emirates

This study proposes a novel problem formulation for a planning distributed generation (DG) allocation for microgrids, using the master-slave approach. In the previous planning studies, all DGs have the same operating mode (e.g. operate at unity power factor). For master-slave controlled microgrid, DGs have two possible operating modes: master (non-unity power factor operation) and slave (unity power factor operation). For planning a master-slave controlled microgrid, in addition to DG siting, the optimal DG operating mode is determined by including a new set of constraints in the planning problem. Thus, the proposed formulation is capable of determining the optimal location of the master and slave DGs with the main objective of minimizing the microgrid's energy losses. The proposed model is formulated as a mixed-integer non-linear programming problem;incorporated into an optimal power flow framework and tested on the IEEE 38-bus systems considering a variable load profile. In addition to this, sensitivity analysis is carried for case studies with different load types and reactive power injection by the slave DGs in the system (e.g. operate at fixed non-unity power factor). The proposed approach can serve as an efficient tool for utility operators for planning microgrids.

关键词： power generation control power factor power generation reliability nonlinear programming integer programming power distribution control optimisation power distribution reliability distributed power generation sensitivity analysis linear programming load flow planning problem slave DGs mixed-integer nonlinear programming problem optimal power flow framework fixed nonunity power factor utility operators planning microgrids optimal allocation planning master-slave controlled microgrids novel problem formulation planning distributed generation master-slave approach optimisation problem previous planning studies master-slave controlled microgrid possible operating modes nonunity power factor operation unity power factor operation optimal DG operating mode

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Fast Homotopy Method for Asteroid Landing Trajectory Optimization Using Approximate Initial Costates

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2019年第3期42卷 585-597页

作者： Yang, Hongwei Li, Shuang Bai, Xiaoli Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 210016 Jiangsu Peoples R China Rutgers State Univ Dept Mech & Aerosp Engn Piscataway NJ 08854 USA

This Paper presents a fast homotopy method for solving fuel-optimal asteroid landing trajectories. Similar to the traditional homotopy method, the fuel-optimal control problem is connected with the energy-optimal control problem via a homotopy function of the performance index. Originally, the initial costates are solved more systematically here. A homotopy function of the dynamical equation is proposed to connect the energy-optimal control problem with a gravity-free energy-optimal control problem for which the generalized gravity is zero. The gravity-free energy-optimal control problem is further linked to an approximate optimal-control problem that has an analytical solution, through selecting appropriate coefficients of the performance index and neglecting the thrust magnitude constraint. Based on the initial costates analytically obtained, an algorithm is proposed to solve the original fuel-optimal control problem. The effectiveness and efficiency of the proposed method are validated through simulations of spacecraft landing on 433 Eros with medium thrust and landing on 101955 Bennu with low thrust.

关键词： Transversality Condition Asteroids Spacecraft Landing Coefficient of Performance nonlinear programming Interplanetary Mission Numerical Integration Terminal Sliding Mode Soft Landing Gauss Pseudospectral Method

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A predicting model for properties of steel using the industrial big data based on machine learning

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COMPUTATIONAL MATERIALS SCIENCE 2019年 160卷 95-104页

作者： Guo, Shun Yu, Jinxin Liu, Xingjun Wang, Cuiping Jiang, Qingshan Chinese Acad Sci Shenzhen Inst Adv Technol Shenzhen 518000 Guangdong Peoples R China Xiamen Univ Coll Mat Xiamen 361000 Fujian Peoples R China Xiamen Univ Fujian Prov Key Lab Mat Genome Xiamen 361000 Fujian Peoples R China Harbin Inst Technol State Key Lab Adv Welding & Joining Harbin 150001 Heilongjiang Peoples R China Harbin Inst Technol Shenzhen Inst Mat Genome & Big Data Shenzhen 518000 Guangdong Peoples R China

Extracting the valuable information about the connections between the overall properties and the related factors from the industrial big data of materials is of significant interest to the materials engineering. At present, most data-driven approaches focus on building a relation model for a single property of the materials, where it may ignore the restrictive boundaries of other properties. In this paper, we propose a machine-learning-based method using nonlinear programming for multiple properties of the materials, and solve the problem by using the Interior Point Algorithm. The key idea is to take the mapping functions corresponding to the properties of the materials as the constraints of the nonlinear programming problem, thus it is capable of processing the restrictions of these properties. Moreover, with our method, the possible boundaries of these properties under certain conditions can be calculated. Experiments results on steel production data demonstrate the rationality and reliability of the proposed method.

关键词： Big data Machine learning Regression Steel properties nonlinear programming

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Partition-based optimization model for generative anatomy modeling language (POM-GAML)

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BMC BIOINFORMATICS 2019年第SUPPL 2期20卷 99-114页

作者： Demirel, Doga Cetinsaya, Berk Halic, Tansel Kockara, Sinan Ahmadi, Shahryar Univ Arkansas Dept Comp Sci Little Rock AR 72204 USA Univ Cent Arkansas Dept Comp Sci Conway AR 72035 USA Univ Arkansas Med Sci Dept Orthoped Surg Little Rock AR 72205 USA

BackgroundThis paper presents a novel approach for Generative Anatomy Modeling Language (GAML). This approach automatically detects the geometric partitions in 3D anatomy that in turn speeds up integrated non-linear optimization model in GAML for 3D anatomy modeling with constraints (e.g. joints). This integrated non-linear optimization model requires the exponential execution time. However, our approach effectively computes the solution for non-linear optimization model and reduces computation time from exponential to linear time. This is achieved by grouping the 3D geometric constraints into *** community detection algorithms (k-means clustering, Clauset Newman Moore, and Density-Based Spatial Clustering of Applications with Noise) were used to find communities and partition the non-linear optimization problem into sub-problems. GAML was used to create a case study for 3D shoulder model to benchmark our approach with up to 5000 *** results show that the computation time was reduced from exponential time to linear time and the error rate between the partitioned and non-partitioned approach decreases with the increasing number of constraints. For the largest constraint set (5000 constraints), speed up was over 2689-fold whereas error was computed as low as 2.2%.ConclusionThis study presents a novel approach to group anatomical constraints in 3D human shoulder model using community detection algorithms. A case study for 3D modeling for shoulder models developed for arthroscopic rotator cuff simulation was presented. Our results significantly reduced the computation time in conjunction with a decrease in error using constrained optimization by linear approximation, non-linear optimization solver.

关键词： Modeling language for human anatomy Arthroscopic rotator cuff Virtual human anatomy nonlinear programming Partition-based optimization

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Using a spectral scaling structured BFGS method for constrained nonlinear least squares

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OPTIMIZATION METHODS & SOFTWARE 2019年第4期34卷 693-706页

作者： Bidabadi, N. Yazd Univ Fac Math Sci Yazd Iran

In this paper, we use a spectral scaled structured BFGS formula for approximating projected Hessian matrices in an exact penalty approach for solving constrained nonlinear least-squares problems. We show this spectral scaling formula has a good self-correcting property. The reported numerical results show that the use of the spectral scaling structured BFGS method outperforms the standard structured BFGS method.

关键词： nonlinear programming constrained nonlinear least squares exact penalty methods spectral scaling structured BFGS method

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