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Optimization Control of Multi-Mode Coupling All-Wheel Drive System for Hybrid Vehicle

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 340-355页

作者： Lipeng Zhang Zijian Wang Liandong Wang Changan Ren school of Vehicle and Energy Yanshan UniversityQinhuangdao 066004China

The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing *** optimization of the power and economy of hybrid vehicles becomes an issue.A unique multi-mode coupling(MMC)AWD hybrid system is presented to realize the distributed and centralized driving of the front and rear axles to achieve vectored distribution and full utilization of the system power between the axles of *** on the parameters of the benchmarking model of a hybrid vehicle,the best model-predictive control-based energy management strategy is ***,the drive system model was built after the analysis of the MMC-AWD’s drive ***,three fundamental strategies were established to address power distribution adjustment and battery SOC maintenance when the SOC changed,which was followed by the design of a road driving force ***,the energy consumption rate in the average time domain was processed before designing the minimum fuel consumption controller based on the equivalent fuel consumption ***,the advantage of the MMC-AWD was confirmed by comparison with the dynamic performance and economy of the BYD Song PLUS *** findings indicate that,in comparison to the comparative hybrid system at road adhesion coefficients of 0.8 and 0.6,the MMC-AWD’s capacity to accelerate increases by 5.26%and 7.92%,*** the road adhesion coefficient is 0.8,0.6,and 0.4,the maximum climbing ability increases by 14.22%,12.88%,and 4.55%,*** a result,the dynamic performance is greatly enhanced,and the fuel savings rate per 100 km of mileage reaches 12.06%,which is also very *** proposed control strategies for the new hybrid AWD vehicle can optimize the power and economy simultaneously.

关键词： Hybrid vehicle All-wheel drive Multi-mode coupling Energy management Model predictive control

Customer Joining Behavior and Regulation Strategy in Visible Multi-Server Queues with Synchronous Vacations of Partial Servers

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Journal of Systems Science & Complexity 2024年第3期37卷 1209-1232页

作者： SUN Wei WANG Hao XIE Xumeng LI Shiyong school of Economics and Management Yanshan UniversityQinhuangdao 066004China

This paper studies customer joining behavior and system regulation strategy in nonexhaustive visible M/M/m queues with synchronous vacations of a part of the *** this part of the servers are idle,they take multiple vacations simultaneously(vacation period).Until there are customers waiting in the queue,they are reactivated and all servers are busy or idle(busy period).The authors call this part of the servers as“partial servers”.In view of the fully visible queue and the almost visible queue,the authors obtain customers’equilibrium joining threshold strategies and their socially optimal joining threshold strategies,respectively,and observe that customer joining behavior in equilibrium generally makes the system overcrowded,which makes the equilibrium social welfare lower than the optimal social *** regulation,interestingly,for optimizing social welfare,the system manager hopes not only customers arriving in vacation period pay attention to the number of partial servers,but also customers arriving in busy period should care about it rather than ***,arranging more servers for vacation does not necessarily lead to the decrease of social welfare on condition that the number of partial servers is close to *** for the information advantage of the fully visible case,it is not obvious for increasing social welfare and even unfavorable to servers’profit unless the number of partial servers is big ***,given the different composition of social welfare,there exists the optimal number of partial servers and the optimal arrival rate of customers for maximizing social welfare.

关键词： Customer behavior non-exhaustive service partial servers regulation strategy synchronous vacations visible queue

Non-Convex Optimization of Resource Allocation in Fog Computing Using Successive Approximation

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Journal of Systems Science & Complexity 2024年第2期37卷 805-840页

作者： LI Shiyong LIU Huan LI Wenzhe SUN Wei school of Economics and Management Yanshan UniversityQinhuangdao 066000China

Fog computing can deliver low delay and advanced IT services to end users with substantially reduced energy ***,with soaring demands for resource service and the limited capability of fog nodes,how to allocate and manage fog computing resources properly and stably has become the ***,the paper investigates the utility optimization-based resource allocation problem between fog nodes and end users in fog *** authors first introduce four types of utility functions due to the diverse tasks executed by end users and build the resource allocation model aiming at utility ***,for only the elastic tasks,the convex optimization method is applied to obtain the optimal results;for the elastic and inelastic tasks,with the assistance of Jensen’s inequality,the primal non-convex model is approximated to a sequence of equivalent convex optimization problems using successive approximation ***,a two-layer algorithm is proposed that globally converges to an optimal solution of the original ***,numerical simulation results demonstrate its superior performance and *** with other works,the authors emphasize the analysis for non-convex optimization problems and the diversity of tasks in fog computing resource allocation.

关键词： Fog computing non-convex optimization optimal resource allocation successive approximation method utility function

Differential distribution of fibrovascular proliferative membranes in 25-gauge vitrectomy for proliferative diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1462-1468页

作者： Nan Lu Shi-Lin Yang Shuo Guo Dong-Ni Yang Li Liu Chun-Hui Fan Ying Guo Jian Liu Wei Zhao Department of Ophthalmology the First Hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina school of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004Hebei ProvinceChina

AIM:To analyze the distribution of fibrovascular proliferative membranes(FVPMs)in proliferative diabetic retinopathy(PDR)patients that treated with pars plana vitrectomy(PPV),and to evaluate the outcomes ***:This was a retrospective and cross-sectional *** 25-gauge(25-G)PPV cases operated for PDR from May 2018 to April *** to the FVPMs images outlined after operations,subjects were assigned into three groups:arcade type group,juxtapapillary type group,and central type *** patients were followed up for over one *** characteristics,operation-related variables,postoperative parameters and complications were ***:Among 103 eyes recruited,the FVPMs distribution of nasotemporal and inferiosuperioral was significantly different(both P<0.01),with 95(92.23%)FVPMs located in the nasal quadrants,and 74(71.84%)in the *** eyes with a central FVPM required the longest operation time,with silicon oil used in most patients,generally combined with tractional retinal detachment(RD)and rhegmatogenous RD,the worst postoperative bestcorrected visual acuity(BCVA)and the highest rates of recurrent RD(all P<0.05).FVPM type,age of onset diabetes mellitus,preoperative BCVA,and combined with tractional RD and rhegmatogenous RD were significantly associated with BCVA improvement(all P<0.05).Compared with the central type group,the arcade type group had higher rates of BCVA ***:FVPMs are more commonly found in the nasal and inferior mid-peripheral retina in addition to the area of arcade *** 25-G PPV for treating PDR eyes with central FVPM have relatively worse prognosis.

关键词： proliferative diabetic retinopathy fibrovascular proliferative membrane 25-gauge pars plana vitrectomy

Boosting overall saline water splitting by constructing a strain-engineered high-entropy electrocatalyst

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Carbon Energy 2024年第2期6卷 154-166页

作者： Ateer Bao Yaohang Gu Yuxuan Zhang Bowen Zhang Juncheng Wu Bo Ni Xiaoyan Zhang Haijun Pan Xiwei Qi school of Materials Science and Engineering Northeastern UniversityShenyangChina school of Resources and Materials Northeastern University at QinhuangdaoQinhuangdaoChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province Northeastern University at QinhuangdaoQinhuangdaoChina College of Metallurgy and Energy North China University of Science and TechnologyTangshanChina

High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inherent ***,a strain engineering methodology is proposed to design transition-metal-based HEM by Li manipulation(LiTM)with tunable lattice strain,thus tailoring the electronic structure and boosting electrocatalytic *** confirmed by the experiments and calculation results,tensile strain in the LiTM after Li manipulation can optimize the d-band center and increase the electrical ***,the asprepared LiTM-25 demonstrates optimized oxygen evolution reaction and hydrogen evolution reaction activity in alkaline saline water,requiring ultralow overpotentials of 265 and 42 mV at 10 mA cm−2,*** strikingly,LiTM-25 retains 94.6%activity after 80 h of a durability test when assembled as an anion-exchange membrane water ***,in order to show the general efficacy of strain engineering,we incorporate Li into electrocatalysts with higher entropies as well.

关键词： d-band center electrical conductivity high-entropy electrocatalyst lattice-strain engineering saline/alkaline water splitting

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun Gao Yan Peng school of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Biomimetic Lightweight Design of Legged Robot Hydraulic Drive Unit Shell Inspired by Geometric Shape of Fish Bone Rib Structure

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Journal of Bionic Engineering 2024年第3期21卷 1238-1252页

作者： Zhipeng Huang Xinjie Li Xikang Guan Xueqing Sun Chenxu Wang Yuepeng Xu Bin Yu Xiangdong Kong school of Mechanical Engineering Yanshan UniversityQinhuangdao066004China school of Arts and Design Yanshan UniversityQinhuangdao066004China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao066004China

The lightweight design of hydraulic quadruped robots,especially the lightweight design of the leg joint Hydraulic Drive Unit(HDU),can improve the robot's response speed,motion speed,endurance,and load ***,the lightweight design of HDU is a huge challenge due to the need for structural *** paper is inspired by the geometric shape of fish bones and biomimetic reinforcing ribs on the surface of the HDU shell are designed to increase its strength and reduce its ***,a HDU shell with biomimetic fish bone reinforcing ribs structure is ***,the MATLAB toolbox and ANSYS finite element analysis module are used to optimize the parameters of the biomimetic reinforcing ribs structure and the overall layout of the ***,the HDU shell is manufactured using additive manufacturing technology,and a performance testing platform is built to conduct dynamic and static performance tests on the designed *** experimental results show that the HDU with biomimetic fish bone reinforcing ribs has excellent dynamic performance and better static performance than the prototype model,and the weight of the shell is reduced by 20%compared to the prototype *** work has broad application prospects in the lightweight and high-strength design of closed-pressure vessel components.

关键词： Hydraulic drive unit Lightweight design of shell Biomimetic fish bone structure design Dynamic and static performance testing

Product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

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Journal of Systems Science & Complexity 2024年第2期37卷 729-758页

作者： YUE Dequan ZHANG Yuying XU Xiuli YUE Wuyi school of Science Yanshan UniversityQinhuangdao 066004China school of Economics and Management Yanshan UniversityQinhuangdao 066004China The Kyoto College of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Identification of Motor Nuclei in the Medulla Oblongata of Carp for Biological Control

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Journal of Bionic Engineering 2024年第2期21卷 842-851页

作者： Yang Zhao Yong Peng Yudong Wen Lingjun Han Yanhong Yan Xueying Dong Hui Zhang Zheng Zhao Xiaoyue Liu school of Electrical Engineering Yanshan UniversityQinhuangdao066004China school of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Key Laboratory of National Defense of Mechanical Structure and Material Science Under Extreme Conditions Yanshan UniversityQinhuangdao066004China Institute of Marine Science and Engineering Yanshan UniversityQinhuangdao066004China Shijiazhuang University Shijiazhuang050035China

Brain-controlled technology is the key technology in biological control,and the corresponding relationship between animal brain nuclei and motor behavior is the *** purpose of this study was to explore the motor nuclei of the medulla oblongata in *** carps were subjected to electrical stimulation and chemical stimulation experiments,respectively,in the water-free state,and the effective chemical stimulation sites were injected with the pontamine sky blue *** brain tissue sections were obtained by paraffin tissue section technology and the neutral red staining *** comparing the positions of the brain nuclei shown in earlier studies,the motor nerve nuclei in the medulla oblongata were *** brain electrode was implanted into the motor nucleus of the medulla oblongata,and the underwater control experiment and behavioral tests were carried out with different electrical stimulation *** results showed that the abducens nucleus(NVI)was the motor nucleus that controls the ipsilateral steering,and the facial nucleus(NVII)was the motor nucleus that controls the forward *** adjusting the stimulation voltage and the stimulation pulse number,the carp can be stably controlled to achieve a left–right steering motion of 30°–180°and a forward motion of more than 80 cm/*** study indicated that the quantitative control of the steering and forward behavior of the carp can be achieved by electrical stimulation of the NVI and NVII,which provided a certain experimental basis for the accurate control of the carp robot.

关键词： Biological control Carp Medulla oblongata motor nucleus Electrical stimulation technique Chemical stimulation technique