作者机构：
[Yan, Hongyu; Xie, Suchao; Jing, Kunkun; Wang, Hao] Cent South Univ, Key Lab Traff Safety Track, Minist Educ, Changsha, Peoples R China.;[Yan, Hongyu; Xie, Suchao; Jing, Kunkun; Wang, Hao] Cent South Univ, Sch Traff & Transportat Engn, Changsha, Peoples R China.;[Zhou, Hui] Cent South Univ Forestry & Technol, Sch Logist & Transportat, Changsha, Peoples R China.;[Xie, SC; Xie, Suchao] Cent South Univ, Key Lab Traff Safety Track, Minist Educ, Changsha 410075, Peoples R China.
通讯机构：
[Xie, SC ] C;Cent South Univ, Key Lab Traff Safety Track, Minist Educ, Changsha 410075, Peoples R China.
关键词：
dual-scale RVE model;homogenization analysis;visualization and adjustment of elastic modulus
摘要：
Utilizing computer tomography (CT) to obtain detailed parameter models, we established a dual‐scale model comprising experimentally validated microscopic (RVE) and macroscopic RVE. We assessed the impact of yarn fiber volume fraction and weaving distance on the elastic properties of the yarn and provided a formula that combines these two factors to adjust the in‐plane orthogonal Young's modulus. Abstract Three‐dimensional (3D) orthogonal woven composites can overcome the drawback of weak interlaminar strengths in traditional laminated composites and exhibit excellent resistance to out‐of‐plane impact, however, the significant difference in properties in the in‐plane orthogonal direction will limit the potential range of application thereof. Predicting elastic properties and exploring methods of adjustment are therefore of paramount importance. Using computed tomography (CT) scanning to obtain detailed parameter models, a corresponding dual‐scale model of microscopic representative volume element (RVE) and mesoscopic RVE was established, and the accuracy of the model was experimentally validated, which can predict the elastic properties of materials. In addition, the influences of the yarn fiber volume fraction and weaving distance on elastic properties were evaluated using the elastic modulus visualization method, and a formula integrating these two factors is provided for adjustment of the in‐plane orthogonal Young's modulus. Highlights Experimentally validated microscale and mesoscale RVE models were established. The influences of factors on elastic properties were visualized. The relationship between Young's modulus and influencing factors was derived. A reliable strategy for adjusting the in‐plane Young's modulus was proposed.
摘要：
The constrained-domination principle (CDP) is one of the most popular constraint-handling techniques (CHTs), since it is simple, nonparametric, and easily embedded in unconstrained multiobjective evolutionary algorithms (MOEAs). However, the CDP overly emphasizes the importance of feasibility, which may lead to the search getting stuck in some locally feasible regions or locally optimal, especially when encountering problems with discontinuous and/or narrow feasible regions. This article seeks to capitalize on the strengths of the CDP while overcoming its weaknesses. Accordingly, we propose a novel constrained MOEA (called MOEA/D-LCDP), in which the CDP is applied in a local manner. Unlike most CHTs that emphasize feasibility, which use the feasibility rule in the whole search space, the proposed localized CDP only adopts the CDP within the niche. That is, to maintain the diversity of the population, only solutions within the niche are compared based on the localized CDP. The niche radius is determined a priori by the acute angle between the current subproblem and its nearest subproblem. Additionally, a population-based status detection strategy is developed to allocate computing resources more rationally, and a diversity-enhanced CDP is designed to enhance the exploitation of the search. Comprehensive experiments conducted on four benchmark test suites with a total of 34 problems and three real-world applications demonstrate that MOEA/D-LCDP is very competitive with representative algorithms.
作者机构：
[Huang, Yin] Cent South Univ Forestry & Technol, Sch Logist & Transportat, Changsha 410004, Peoples R China.
通讯机构：
[Yin Huang] A;Author to whom correspondence should be addressed.
关键词：
distribution industry;poverty-stricken county;county economy;rural development;spatial characteristics;factors influencing
摘要：
Under the background of rural revitalization and domestic and international double circulation, vigorously developing the rural distribution industry is an important measure needed to accelerate the process of urban–rural integration, and to enhance the effect of poverty alleviation. In this study, 36 poverty-stricken counties in the southeast of Henan Province, China were selected as research objects; the evolution characteristics and factors influencing the counties’ distribution industries and their development were studied, using the modified gravity model, exploratory spatial data analysis, and a spatial econometric model. The overall scale of the county-level distribution industry in the poverty-stricken areas of southeast Henan expanded, but regional development was uneven, and a spatial pattern of “high in the northeast–low in the southwest” was demonstrated. Meanwhile, the development of the distribution industry in the counties of the district had a circular spatial trend of “agglomeration–diffusion–agglomeration”, with a significant local spatial polarization effect. In addition, the technology level, market demand, population size, and industrial structure adjustment had positive spatial spillover effects on the development of counties’ distribution industries, while labor and capital exerted negative spatial spillover effects. On this basis, to promote the interactive development of the distribution industry and rural economic growth and further accelerate the process of urban–rural integration, we should continually optimize the spatial layout of the distribution industry, improve the construction of county-level circulation infrastructure, and boost new circulation formats and models.
摘要：
In this study, we formulate a freight vehicle path-planning model in the context of dynamic time-varying networks that aims to capture the spatial and temporal distribution characteristics inherent in the carbon dioxide emission trajectories of freight vehicles. Central to this model is the minimization of total carbon dioxide emissions from vehicle distribution, based on the comprehensive modal emission model (CMEM). Our model also employs the freight vehicle travel time discretization technique and the dynamic time-varying multi-path selection strategy. We then design an improved genetic algorithm to solve this complicated problem. Empirical results vividly illustrate the superior performance of our model over alternative objective function models. In addition, our observations highlight the central role of accurate period partitioning in time segmentation considerations. Finally, the experimental results underline that our multi-path model is able to detect the imprint of holiday-related effects on the spatial and temporal distribution of carbon dioxide emission trajectories, especially when compared to traditional single-path models.
作者机构：
[Jiang, Shuxia] Cent South Univ Forestry & Technol, Sch Traff & Logist, Changsha 410004, Peoples R China.;[Liu, Nian] Michigan State Univ, Dept Stat & Probabil, E Lansing, MI 48824 USA.;[Liu, Yuanyuan] Cent South Univ, Sch Math & Stat, HNP LAMA, New Campus, Changsha 410083, Peoples R China.
通讯机构：
[Yuanyuan Liu] S;School of Mathematics and Statistics, HNP-LAMA, New Campus, Central South University, Changsha 410083, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
We consider the computing issues of the steady probabilities for block-structured discrete-time Markov chains that are of upper-Hessenberg or lower-Hessenberg transition kernels with a continuous phase set. An effective computational framework is proposed based on the wavelet transform, which extends and modifies the arguments in the literature for quasi-birth-death (QBD) processes. A numerical procedure is developed for computing the steady probabilities based on the fast discrete wavelet transform, and several examples are presented to illustrate its effectiveness.
摘要：
Triply periodic minimal surface (TPMS) has many excellent properties, such as stable energy absorption, a high specific strength, a large surface area, etc. The functional multi-stage design and research of TPMS lattices were carried out to improve the mechanical performance. The deformation modes and curves of three uniform TPMS lattices (Primitive, Gyroid, and Diamond) and their hybrid lattices were analyzed by quasi-static compression experiments and numerical simulations. Based on the uniform TPMS lattice, hybrid sheet TPMS lattices were designed to realize the multi-stage energy absorption (multi-stage platform) and multi-stage protection integrated porous structure. The two-stage energy absorption characteristics of hybrid sheet TPMS lattices were systematically studied, and the effects of hybrid TPMS composition, width of the transition layer, relative weight, and hybridization method on the multi-stage energy absorption were obtained. The results indicated that the Gyroid-Diamond hybrid lattice performed the best, with the specific energy absorption (SEA) increasing by 30.48% and 0.51%, and the yield stress decreasing by 14.01% and 30.07%, respectively, as compared to the single TPMS lattice. Width of the transition layer has little effect on the two-stage energy absorption. The relative weight will shorten or widen the length of the two-stage platform stress. The hybridization method shows that the sequence hybridization along the loading direction based on the TPMS lattice yield strength is the best arrangement to achieve the effect of multi-stage energy absorption. Finally, the three-stage energy absorption characteristics of hybrid Primitive-Gyroid-Diamond lattices are further studied. The results show that with the increase of layers of TPMS lattices, the fluctuation of the multi-stage curve and the yield stress will increase.
作者机构：
[Song, Rui; Shi, Wen; Song, R; Qin, Wanyi] Cent South Univ Forestry & Technol, Sch Logist & Transportat, Changsha, Peoples R China.;[Xue, Xingjian] Cent South Univ Forestry & Technol, Sch Landscape Architecture, Changsha, Peoples R China.
通讯机构：
[Song, R ] C;Cent South Univ Forestry & Technol, Sch Logist & Transportat, Changsha, Peoples R China.
摘要：
To achieve low-carbon and green mobility, the government needs to encourage people to buy and use new energy vehicles. This study proposes a tripartite evolutionary game model among new energy vehicle manufacturers, consumers, and government agencies. The game strategy combinations of each party and the stability conditions of the equilibrium point in the evolutionary game system are analyzed, and the validity of the conclusions is verified by simulation results. Compared with traditional studies that suggest the government should adopt the direct subsidy policy, this study shows that in the early stage of new energy vehicle development, government subsidies are still important for the rapid growth of new energy vehicle production and sales, but indirect policies can play a key role as the new energy vehicle industry matures. In addition to the price, the attractiveness of vehicle brands, the perceived utility of the products among consumers, and the coverage of charging infrastructure in cities also determine whether consumers decide to purchase and use new energy vehicles. The findings could provide useful recommendations for governments and manufacturers of new energy vehicles to meet their "dual carbon" targets.
摘要：
Urban traffic congestion is often concentrated at urban intersections. An urban road traffic signal control system is needed to prevent problems such as driving delays caused by frequent traffic congestions on trunk lines, exhaust emissions owing to frequent start and stop of vehicles, and fuel wastage due to long idling times. Maximizing the traffic capacity of an intersection and reducing the delay rate of vehicles has always been a problem for traffic control research. The coordinated control of urban traffic signals is regarded as a multi-objective optimization problem. A mathematical model for urban trunk traffic is studied herein. An average delay model, average queue length model, total delay calculation model for vehicles at intersections, and vehicle exhaust emission model are established to obtain an optimization model for a new traffic trunk coordinated control system. In addition, our study combines the fuzzy control theory with the adaptive sequencing mutation multi-objective differential evolution algorithm (FASM-MDEA). This new optimization method for traffic signal control at urban intersections is proposed as a solution for the traffic flow optimization model to solve the problem of traffic signal coordination and control of urban trunk lines. The simulation results demonstrate the effectiveness of the model optimization algorithm proposed in this study.
摘要：
To improve the energy absorption characteristics of the traditional convex polygonal tube and the existing concave polygonal tube, a new evolutionary scheme for the concave polygonal tube was proposed. The energy absorption characteristics of different concave tubes evolved from the common scheme (Scheme-I) and the new evolution scheme (Scheme-II) were studied through quasi-static compression experiments and numerical simulations. The results show that under the same mass, the concave polygonal tube evolved by Scheme-II has better energy absorption characteristics. The folded half-wavelength is smaller at the same compression distance, and compared with the traditional pentagon tube, the energy absorption (EA) of the pentagon concave of Scheme-II (N5E-CT) is improved by 218%, and the crushing force efficiency (CFE) is improved by 69%. Secondly, the mean crushing force of convex and concave tubes is derived and verified by the folded element theory. The mode of deformation of concave tubes under different structural sizes was investigated, and the size range within which the concave tube can remain stable was obtained. In addition, the evolution of the specific energy absorption (SEA) of the concave tubes was explored, and the SEA and the number of structural sides ( N) show a trend of first increasing and then decreasing. Finally, the multi-objective optimization of the pentagon concave tube with excellent energy absorption characteristics was conducted, and the initial peak crushing force of the optimized structure was reduced by 19.92%.
作者机构：
[Hu, Hanli; Yi, Dan] Changsha Univ Sci & Technol, Sch Econ & Management, Changsha 410114, Peoples R China.;[Cao, Y; Cao, Yu] Cent South Univ, Sch Business, Changsha 410083, Peoples R China.;[Li, Qingsong] Cent South Univ Forestry & Technol, Sch Transportat & Logist, Changsha 410004, Peoples R China.
通讯机构：
[Cao, Y ] C;Cent South Univ, Sch Business, Changsha 410083, Peoples R China.
关键词：
green products;brown products;agent selling;direct selling;pricing strategies
摘要：
In order to respond to and take advantage of consumers’ growing interest in green products, an increasing number of firms are expanding their market share by introducing green versions of their brown products. However, firms are faced with the challenge of how to distribute green products to avoid mutual encroachment with brown products. To solve this problem, this paper constructs a Stackelberg game model consisting of a manufacturer (leader) and a retailer (follower), in which the manufacturer provides brown and green products, and then develops two channel structures for green products to be sold through the manufacturer (direct selling) and the retailer (agent selling). The results show that the manufacturer’s choice of green product distribution channels is affected by the direct selling costs and the market share of green consumers and their product preferences. When the direct selling cost is zero or consumers are green, the manufacturer always chooses direct selling. However, with an increase in the direct selling costs, if green consumers have a large difference in their preference for green and brown products, the manufacturer chooses agent selling, and vice versa. In particular, the impact of the market share of green consumers on the profits of the manufacturer is different in the two channel structures. The higher the market share of green consumers under agent selling, the more beneficial it is for the manufacturer. However, under direct selling, the profits of the manufacturer show an “inverted U” trend with the increase in the market share of green consumers. In addition, under certain conditions, the direct selling channels opened by the manufacturer are not necessarily to sell green products, but to maximize the market share of brown products. The strategy is to set high prices for green products in direct selling channels to stimulate consumers to buy brown products. These findings can provide insights for manufacturers to design appropriate green product distribution strategies.
摘要：
The loading outline of railway out-of-gauge freight (ROF) is beyond the railway gauge due to its larger size. The choice of a safe and economical transportation route according to the characteristics of the freights in the railway network becomes an important issue for the railway out-of-gauge freight transportation. A proposed methodology is presented in this paper with the aim to solve the problems in the railway out-of-gauge freight transportation route decision -making (ROF-TRD) process in which safety distances between the railway gauges and freight loading outlines, the curve radius and the arrival-departure traffic flow balance are taken into consideration while the railway capacity losses and transportation costs being as objective functions to construct the route decision-making model considering gauge modification. The proposed route search algorithm can be used in the model to further refine the design of an effective safety distance bilateral detection. The case study verification shows that the safest and most economical railway out-of-gauge freight transportation route can be obtained by applying the proposed model, and the results demonstrate that taking railway capacity loss and modified costs of possible ROF routes into consideration, the optimal route can save around 10-22 % of total costs.(c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/ 4.0/).
期刊：
International Journal of Mechanical Sciences,2023年256:108509 ISSN：0020-7403
通讯作者：
Xie, SC
作者机构：
[Zhang, Jing; Xie, SC; Xie, Suchao; Tan, Hongchuang; Ma, Wen; Yang, Chengxing] Cent South Univ, Key Lab Traff Safety Track, Changsha, Hunan, Peoples R China.;[Xie, SC; Xie, Suchao; Tan, Hongchuang] Cent South Univ, Sch Traff & Transportat Engn, Changsha, Peoples R China.;[Xie, SC; Xie, Suchao; Tan, Hongchuang] Joint Int Res Lab Key Technol Rail Traff Safety, Changsha, Peoples R China.;[Zhou, Hui] Cent South Univ Forestry & Technol, Sch Logist & Transportat, Changsha, Peoples R China.
通讯机构：
[Xie, SC ] C;Cent South Univ, Key Lab Traff Safety Track, Changsha, Hunan, Peoples R China.;Cent South Univ, Sch Traff & Transportat Engn, Changsha, Peoples R China.;Joint Int Res Lab Key Technol Rail Traff Safety, Changsha, Peoples R China.
关键词：
Sensible multiscale symbol dynamic entropy;Feature extraction;Time series;Rolling bearing;Fault diagnosis
摘要：
Due to the complex service conditions of rolling bearings, vibration signals arising therefrom exhibit non-linear characteristics, which means that single-scale feature extraction techniques cannot extract fault features. Multiscale symbolic dynamic entropy (MSDE) is a new technique that has recently emerged and been applied to fault diagnosis in machinery. However, MSDE has limitations such as its poor stability, large errors, and even loss of information. To this end, a novel sensible multiscale symbol dynamic entropy (SMSDE) method was proposed. For SMSDE, the signal was first decomposed using empirical mode decomposition, and then the useful intrinsic mode functions were selected for reconstruction to decrease noise. Secondly, the slippage-averaging multiscale approach was designed to coarse-grain the signal, which considers the connection of data before and after the breakpoint, thus reducing the error. The method can not only decrease noise, but also avoid the loss of key information, thereby extracting sensitive feature information. The results with multiple synthesized signals show that the proposed method is more robust than the other eight entropy methods. Furthermore, the real bearing signals of the three cases indicate that compared with other advanced entropy methods, SMSDE can better distinguish the various states of the bearing.
