检索结果-内蒙古大学图书馆

Intelligent workload allocation in IoT-Fog-cloud architecture towards mobile edge computing

COMPUTER COMMUNICATIONS 2021年 169卷 71-80页

作者： Abbasi, M. Mohammadi-Pasand, E. Khosravi, M. R. Bu Ali Sina Univ Fac Engn Dept Comp Engn Hamadan Hamadan Iran Persian Gulf Univ Dept Comp Engn Bushehr Iran Shiraz Univ Technol Dept Elect & Elect Engn Telecommun Grp Shiraz Iran

Because of the tremendous growth in the number of smart vehicular devices and 5G mobile technologies, the Internet of Things (IoT) has experienced rapid expansion. This has led to a considerable increase in the volume of sensory data produced from, but not limited to, monitoring devices, traffic congestion in cities, safety, and pollution control. Cloud computing can deal with the corresponding workload by providing virtually unlimited computational resources. But, given the importance of the quality of service and security in delay-sensitive requests, other solutions like fog computing have also been introduced to speed up processing and management of sensory data in real scenarios like smart grid and IoT. Processing workloads at the network edge reduces the delay in mobile edge computing, but it highly increases the consuming power. Therefore, there is an urgent need for the improvement of the energy model of fog devices at the network edge. This paper is an attempt to modify this model using the green energy concept and reduce both delay and power consumption in multi-sensorial frameworks in secure IoT systems. In the proposed method, a genetic algorithm (GA) is used for handling a large number of requests and the corresponding quality and security limitations. Simulation results show that the proposed method can simultaneously reduce the delay and the power consumption of edge devices compared to a baseline strategy.

关键词： Internet of Things (IoT) Mobile edge computing (MEC) multi-objective genetic algorithm Workload allocation

来源：评论

学校读者我要写书评

暂无评论

An optimization-based design approach for a novel self-adjuster using shear thickening fluid

引用

STRUCTURAL AND multiDISCIPLINARY OPTIMIZATION 2021年第6期64卷 4161-4179页

作者： Nagy-Gyorgy, P. Bene, J. G. Hos, C. J. Budapest Univ Technol & Econ Dept Hydrodynam Syst Budapest Hungary

Recently, the increasingly strict safety and emission regulations in the automotive industry drove the interest towards automatic length compensating devices, e.g., hydraulic lash adjusters (lower emission) and slack adjuster in brake systems (faster brake response). These devices have two crucial requirements: (a) be stiff during high load, while (b) be flexible in the released state to compensate for environmental effects such as wear and temperature difference. This study aims to use the advantageous properties of shear thickening fluids to develop a less complicated, cost-efficient design. The proposed design is modeled by a system of ordinary differential equations in which the effect of the non-Newtonian fluid flow is taken into account with a novel, simplified, semi-analytical flow rate-pressure drop relationship suitable for handling arbitrary rheology. The adjuster's dimensions are determined with a multi-objective genetic algorithm based on the coupled solid-fluid mechanical model for six different shear thickening rheologies. The accuracy of the simplified flow model is verified by means of steady-state and transient CFD simulations for the optimal candidates. We have found that the dominating parameters of such devices are (a) the shear thickening region of the fluid rheology and (b) the gap sizes, while the piston diameters and the zero viscosity or the critical shear rate of the fluid have less effect. Based on the results, we give guidelines to design similar-length compensating devices.

关键词： multi-objective genetic algorithm Optimal design CFD shear thickening fluid Non-Newtonian fluid Self-adjuster

来源：评论

学校读者我要写书评

暂无评论

Cost-effective sensor placement optimization for large-scale urban sewage surveillance

引用

SUSTAINABLE CITIES AND SOCIETY 2024年 103卷

作者： Wang, Sunyu Xu, Ke Zhou, Yulun Univ Hong Kong Dept Urban Planning & Design Hong Kong Peoples R China Univ Calif Los Angeles Samueli Sch Engn Los Angeles CA 90095 USA Univ Hong Kong Musketeers Fdn Inst Data Sci Hong Kong Peoples R China

Early pandemic outbreak detection in cities is a crucial but challenging task. Complementary to the costly massive individual testing, urban sewage surveillance offers a rare, cost-effective solution for large-scale monitoring of pandemic spread in cities with minimal interference to people's lives. One emerging question is how to derive a cost-effective sensor placement plan in city -scale sewage networks having complicated topologies. Inspired by remote sensing, we first provide a general multi -objective formulation of the optimal sensor placement problem on directed networks. Then, we introduce a connectivity -based objective evaluation approach and embed it into an NSGA-II algorithm to enable efficient optimization on large-scale directed graphs. The effectiveness of the proposed method is verified on a real -world sewage network in Hong Kong serving more than 500,000 urban residents. Results show that the proposed method efficiently generated optimal sensor placement plans on city -scale networks. Optimized sensor placement plans outperformed human placement heuristics by a significant margin of 102%, highlighting the necessity for data -driven decision support for large-scale urban sensing. Methodologically, this study provides a benchmark problem and datasets for network -based spatial optimization studies. Codes and datasets developed in this study are open -sourced to support future research in a real -world scenario.

关键词： Optimal sensor placement Network-based spatial optimization multi-objective genetic algorithm Sewage surveillance Pandemic control

来源：评论

学校读者我要写书评

暂无评论

Optimization Research on the Impact of Charging Load and Energy Efficiency of Pure Electric Vehicles

引用

PROCESSES 2024年第11期12卷 2599页

作者： Xin, Huajian Li, Zhejun Jiang, Feng Mo, Qinglie Hu, Jie Zhou, Junming Guangxi Vocat & Tech Inst Ind Sch Intelligent Mfg Coll Nanning 530001 Peoples R China Guangxi Univ Sci & Technol Sch Mech & Automot Engn Liuzhou 545616 Peoples R China

In this paper, the negative impact of the charging load generated by the disorderly charging scheme of large-scale pure electric vehicles on the operation performance of the power grid system and the problem of reducing its charging energy efficiency are studied and analyzed. First, based on Matlab 2022a simulation software and the Monte Carlo random sampling method, the probability density model of the factors affecting the charging load is constructed, and the total charging load of different quantities is simulated. Second, the IEEE33-node distribution network model is introduced to simulate the influence of charging load on the grid under different permeability schemes. Finally, the multi-objective genetic algorithm is used to optimize the charging cost and battery life. Taking the 20% permeability scheme as an example, the research results show that, compared with the disorderly charging scheme, the multi-objective optimization scheme reduces the peaking valley difference rate by 24.34%, the charging load power generation cost by 29.5%, and the charging cost by 23.9%. The power grid profit increased by 45.8%, and the research conclusion has practical significance for the energy efficiency optimization of pure electric vehicles.

关键词： pure electric vehicles Monte Carlo method IEEE model multi-objective genetic algorithm

来源：评论

学校读者我要写书评

暂无评论

multi-condition stability analysis and lightweight research of mining wide-body dump truck compartment

引用

MEASUREMENT SCIENCE AND TECHNOLOGY 2024年第4期35卷 045603-045603页

作者： Liu, Zhihai Liu, Dongyang Tian, Shaolu Han, Wenyu Zhao, Xieguang Shandong Univ Sci & Technol Coll Transportat Qingdao 266590 Peoples R China Shandong Univ Sci & Technol Coll Mech & Elect Engn Qingdao 266590 Peoples R China Shandong Univ Sci & Technol Coll Intelligent Equipment Tai An 271001 Peoples R China

This paper proposes a multi-condition optimization method based on single condition optimization and weight. This method analyzes and discusses various working states of the wide-body dump truck and optimize its structure. Firstly, the modal shape and natural frequency of the carriage under modal conditions are analyzed using the finite element method. Combined with the mechanic's theory, the carriage's force, deformation, and stress are studied under the turning and partial load conditions. This part provides a basis for subsequent stability analysis and lightweight research. According to the filtering white noise method and differential equation method, the f-class road model and the vehicle system dynamics model are established in MATLAB to study the influence of road vibration on the stability of the dump truck during operation. The carriage vibration data prove that the road vibration causes the low order resonance of the carriage and affects the stability of the dump truck. This part provides a basis for the subsequent stability optimization. Based on the above analysis, a multi-objective genetic algorithm based on the response surface is used to optimize the structural parameters of the carriage under partial load conditions, turning conditions and modal conditions, to realize the optimization of stability, mass, stress and deformation of the carriage. Finally, the entropy weight method is used to fuse the optimization results of the three working conditions. The correctness of the comprehensive optimization results is verified, and the wide-body dump truck carriage optimization is realized, proving the feasibility of the proposed method.

关键词： lightweight excitation frequency response surface optimization multi-objective genetic algorithm weighting

来源：评论

学校读者我要写书评

暂无评论

Performance enhancement of segmented annular thermoelectric generator based on multi-parameter and multi-objective optimization

引用

THERMAL SCIENCE AND ENGINEERING PROGRESS 2024年 47卷

作者： Sun, Yajing Zhai, Pengcheng Wang, Shuhao Duan, Bo Li, Guodong Chen, Gang Wuhan Univ Technol Hubei Key Lab Theory & Applicat Adv Mat Mech Wuhan 430070 Peoples R China Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430070 Peoples R China Natl Univ Singapore Dept Mech Engn Singapore 119077 Singapore

The excellent performance of annular thermoelectric generator (ATEG) is crucial for its commercial application, and it has been validated that the segment configuration can effectively enhance the ATEG performance. Nevertheless, owing to the limitations in conventional optimization methods which fail to simultaneously consider the co-influence of multiple parameters, further exploration is required for achieving optimal design of segmented annular thermoelectric generator (SATEG). In this study, we present a novel approach combining multi-objective genetic algorithm (MOGA) with finite element method to implement the multi-parameter and multi-objective optimization of SATEG. This approach not only reduces the computational cost but also ensures precise control on SATEG temperature below its maximum acceptable operation temperature. Furthermore, the optimization results highlight the importance of emphasizing diversity between p- and n- type TE legs as well as recognizing the different optimal geometrical structures for two types of TE legs, which have been always overlooked in previous researches. By adopting the optimal geometrical structure at a hot end temperature of 600 K, significant improvements in output power of 32.839 % and efficiency of 61.915 % are achieved for SATEG.

关键词： Segmented annular thermoelectric generator multi-parameter and multi-objective optimiza-tion multi-objective genetic algorithm Segment ratio Performance enhancement

来源：评论

学校读者我要写书评

暂无评论

Optimization of energy ratio, benefit to cost and greenhouses gasses using metaheuristic techniques (genetic and particular swarm algorithms) and data envelopment analysis: Recommendations for mitigation of inputs consumption (a case crop: edible onion)

引用

ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY 2022年第6期41卷

作者： Elhami, Behzad Raeini, Mahmoud Ghasemi Nejad Taki, Morteza Marzban, Afshin Heidarisoltanabadi, Mohsen Agr Sci & Nat Resources Univ Khuzestan Dept Agr Machinery & Mechanizat Engn Mollasani Iran AREEO Agr Engn Res Dept Isfahan Agr & Nat Resources Res & Educ Ctr Esfahan Iran

The present study aimed to optimize the energy, economic, and greenhouse effects indices for edible onion production in Fereydan (85 growers), and Buin (15 growers) regions in Isfahan. Required data were collected through direct measurement, interview, and questionnaire. Total energy input was obtained before and after optimization using data envelopment analysis (DEA), multi-objective genetic algorithm (MOGA), and multi-objective particle swarm algorithm (MOPSA), and was determined as 236,335, 213,068 (8.75% saving), 125,663 (48.63% saving), and 320,657 MJ ha(-1) (35.67%), respectively. In addition, energy ratio (ER) was improved from 0.79 to 0.84, 1.81, and 0.8 using DEA, MOGA, and MOPSA, respectively. By reducing the production costs by 10.2%, 63.12%, and 29.4% using DEA, MOGA, and MOPSA, respectively, benefit-to-cost ratio (BCR) index was improved from 1.44 to 1.88, 5.21, and 1.94, respectively. Also results showed that GHG emissions were mitigated by 18.39%, 47.56%, and 27.94%, respectively. Based on the findings, MOGA showed better performance compared to DEA, and MOPSA in terms of ER, BCR, and GHG factors. Despite applying metaheuristic, and artificial intelligence methods by MOPSA, this algorithm was not able to optimize the target factors, and applied the energy, and production costs in negative status (in reverse).

关键词： data envelopment analysis multi-objective genetic algorithm multi-objective particle swarm algorithm transplanting onion

来源：评论

学校读者我要写书评

暂无评论

Experimental investigation on the optimal control of vortex shedding of a circular cylinder with rotating rods at moderate Reynolds numbers

引用

JOURNAL OF FLUIDS AND STRUCTURES 2024年 124卷

作者： Silva, Paulo H. N. Assi, Gustavo R. S. Univ Sao Paulo Dept Naval Architecture & Ocean Engn Escola Politecn Sao Paulo Brazil

This paper presents an experimental study of fluid-structure interaction conducted at Reynolds numbers around 104 with scale models in a water channel. A circular cylinder was equipped with eight control rods positioned around its perimeter to interact with the external flow. Each rod could be driven independently to rotate about its axis. The controlled rotation of the rods interfered with the vortex generation mechanism mitigating the formation of a coherent wake. The results showed that it is possible to simultaneously reduce the mean drag and fluctuating lift forces when the rods rotate at a uniform speed or with each rod set at a different rate. A multi-objective genetic algorithm was employed to find the optimum rotation speeds. The optimum rotation produced a more significant reduction in both objectives and also consumed less energy. The contribution of each rod depends significantly on its angular position around the body and the flow conditions resulting from the upstream control rods. The present work clarifies the physical principles of the phenomenon and paves the way for the development of technological applications.

关键词： Bluff body Flow control Vortex shedding Control rods multi-objective genetic algorithm

来源：评论

学校读者我要写书评

暂无评论

multi-objective Optimization of Underwater Towed System during CourseKeeping Motion

Multi-Objective Optimization of Underwater Towed System duri...

引用

International Conference on Mechanical Design and Simulation (MDS)

作者： Cheng, Yanyan Li, Yunzhou Yang, Chong Kunming Ship Borne Equipment Res & Test Ctr Res Off 1 Kunming Peoples R China

ISBN: (纸本)9781510655263;9781510655256

In this paper, the underwater towed system during the course-keeping motion was taken as the research object, in addition, the governing equation of motion was given as well. By the means of the experimental data obtained by the design of experiment, the second-order polynomial response surface models reflecting the steady-state motion characteristics of the towrope were established. Apart from mentioned above, the tail drag depth and the head tension were taken as objective functions, and the optimal solution set of Pareto was obtained by using the multi-objective optimization algorithm. The results shown that the approximate models were used to optimize the towrope when the parameters of the towrope were within a certain range, which can quickly and accurately analyzed the influences of each parameter on the steady-state motion characteristics of the towrope.

关键词： underwater towed system course-keeping motion optimal Latin hypercube design response surface method multi-objective genetic algorithm

来源：评论

学校读者我要写书评

暂无评论

Optimal design of micro-dimples on crankpin bearing surface for improving engine's lubrication and friction

引用

INDUSTRIAL LUBRICATION AND TRIBOLOGY 2021年第1期73卷 52-59页

作者： Jiao, Renqiang Nguyen, Vanliem Le, Vanquynh Bui, Vancuong Hubei Polytech Univ Sch Mech & Elect Engn Huangshi Hubei Peoples R China Thai Nguyen Univ Technol Fac Automot & Power Machinery Engn Thai Nguyen Vietnam

Purpose The purpose of this paper is to investigate the optimal design of micro-dimples on the bearing surface of the crankpin bearing (CB) to ameliorate the engine's lubrication and friction (ELF). Design/methodology/approach A hydrodynamic model of the CB considering the influence of the asperity contact is built under the impact of the dynamic loading of the slider-crank-mechanism. The micro-dimples on non-slip surface of the bearing are designed and optimized based on the lubrication model and multi-objective genetic algorithm. The performance of optimal micro-dimples on ameliorating the ELF is analyzed and compared with that of optimal CB dimensions via the reduction of the solid contact force, friction force and friction coefficient between the crankpin and bearing surfaces;and the increase of the oil film pressure. Findings The optimal design of micro-dimples on the bearing surface may not only greatly ameliorate the ELF but also make the rotation of the crankpin inside the bearing more stable in comparison with the optimization of CB dimensions. Originality/value This study results not only clearly ameliorates the ELF but also can be applied to the slip/non-slip surface pairs of other journal bearings to enhance their lubrication performance.

关键词： Crankpin bearing Micro-dimples Slip non-slip surfaces Lubrication and friction multi-objective genetic algorithm

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：