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Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei Jiang Chuan Yue Shi-Jun Lei Yu-xin cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Design and grindability assessment with cup shaped electroplated CBN wheel grinding turbine disc slots of powder metallurgy superalloy FGH96

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 521-534页

作者： Li, Benkai Ding, Wenfeng Zhu, Yejun Li, Changhe Zhang, Yanbin Yang, Min Ma, Xiao Liu, Mingzheng cui, xin Qingdao Univ Technol Sch Mech Engn Qingdao 266520 Peoples R China Nanjing Univ Aeronaut & Astronaut Natl Key Lab Sci & Technol Helicopter Transmiss Nanjing 210016 Peoples R China Nanjing Agr Univ Coll Engn Nanjing 210031 Peoples R China

The machining surface integrity of aero-engine turbine disc slots has a significant impact on their fatigue life and service performance, and achieving efficiency and high-precision machining is still a great challenge. The high machining requirements of future aeroengine turbine disc slots will be difficult to satisfy using the broaching method. In addition, existing methods of slot machining face difficulties in ensuring surface integrity. This study explored a cup shaped electroplated Cubic Boron Nitride (CBN) abrasive wheel for profile grinding the turbine disc slots of FGH96 powder metallurgy superalloy. The matrix structure of the cup shaped abrasive wheel was designed and verified. A profile grinding experiment was conducted for fir-tree slots on a five-axis machining center. The accuracy and the surface integrity were analyzed. Results show that the key dimension detection results of the slots were within the allowable tolerance range. Meanwhile, an average surface roughness Ra of 0.55 lm was achieved, the residual stress was compressive, the plastic deformation layer thickness was less than 5 lm, and the hardening layer thickness was less than 20 lm. The research findings provide a new approach to machining the slots of aviation engine turbine discs and guidance for the high-quality processing of complex components. (c) 2023 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics.

关键词： Profile grinding Surface integrity Cup shaped CBN abrasive wheel Turbine disc slots FGH96 OF-THE-ART SURFACE INTEGRITY DYNAMIC RECRYSTALLIZATION FATIGUE SPEED MANUFACTURE PARAMETERS MECHANISM ALLOYS TOOLS

An introductory review on the common brown leafhopper(Orosius orientalis):A new soybean pest

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Oil Crop Science 2024年第3期9卷 198-203页

作者： Tianhao Pei xin cui Shusen Shi Yu Gao College of Plant Protection Jilin Agricultural UniversityChangchun130118PR China Key Laboratory of Soybean Disease and Pest Control Ministry of Agriculture and Rural AffairsChangchun130118PR China

Soybean pests are one of the major factors limiting yield *** the expansion of area and changes in cropping patterns,a number of new pests have been identified in the main soybean production areas of *** common brown leafhopper,Orosius orientalis,is a new pest associated with soybean stay-green virus that has been discovered on cultivated soybean crop in the Yellow-Huai-hai region of China in recent *** polyphagous insect has a wide feeding range and infests a variety of important grain and cash *** paper presents the basic information,geographical distribution,hosts,damage characteristics,plant virus transmission,occurrence patterns,and prevention and control measures *** review also provides insights into integrated prevention and control of the genus Orosius as an insect vector.

关键词： Soybean Leafhopper Plant virus Insect vector Orosius orientalis

Low-intensity pulsed ultrasound reduces alveolar bone resorption during orthodontic treatment via Lamin A/C-Yes-associated protein axis in stem cells

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World Journal of Stem Cells 2024年第3期16卷 267-286页

作者： Tong Wu Fu Zheng Hong-Yi Tang Hua-Zhi Li xin-Yu cui Shuai Ding Duo Liu cui-Ying Li Jiu-Hui Jiang Rui-Li Yang Department of Orthodontics Peking University School and Hospital of StomatologyNational Engineering Laboratory for Digital and Material Technology of StomatologyBeijing Key Laboratory of Digital StomatologyBeijing 100081China Department of Central Laboratory Peking University School and Hospital of StomatologyNational Clinical Research Center for Oral Diseases&National Engineering Laboratory for Digital and Material Technology of StomatologyBeijing Key Laboratory of Digital StomatologyBeijing 100081China

BACKGROUND The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years,which also may lead to some complications such as alveolar bone resorption or tooth root ***-intensity pulsed ultrasound(LIPUS),a noninvasive physical therapy,has been shown to promote bone fracture *** is also reported that LIPUS could reduce the duration of orthodontic treatment;however,how LIPUS regulates the bone metabolism during the orthodontic treatment process is still *** To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement(OTM)model and explore the underlying *** A rat model of OTM was established,and alveolar bone remodeling and tooth movement rate were evaluated via micro-computed tomography and staining of tissue *** vitro,human bone marrow mesenchymal stem cells(hBMSCs)were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction,Western blot,alkaline phosphatase(ALP)staining,and Alizarin red *** expression of Yes-associated protein(YAP1),the actin cytoskeleton,and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA(siRNA)application via *** The force treatment inhibited the osteogenic differentiation potential of hBMSCs;moreover,the expression of osteogenesis markers,such as type 1 collagen(COL1),runt-related transcription factor 2,ALP,and osteocalcin(OCN),*** could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by ***,the expression of LaminA/C,F-actin,and YAP1 was downregulated after force treatment,which could be rescued by ***,the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA ***,LIPUS increased alveolar

关键词： Low-intensity pulsed ultrasound Bone resorption Osteogenesis Cytoskeleton-Lamin A/C-Yes-associated protein axis Bone marrow mesenchymal stem cells Orthodontic tooth movement

Force model in electrostatic atomization minimum quantity lubrication milling GH4169 and performance evaluation

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Frontiers of Mechanical Engineering 2024年第4期19卷 55-72页

作者： Min YANG Hao MA Zhonghao LI Jiachao HAO Mingzheng LIU xin cui Yanbin ZHANG Zongming ZHOU Yunze LONG Changhe LI School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China College of Physics QingdaoUniversityQingdao 266071China Hanergy Lubrication Technology Co. Ltd.Qingdao 266200China

The nickel-based high-temperature alloy GH4169 is the material of choice for manufacturing critical components in aeroengines,and electrostatic atomization minimum quantity lubrication(EMQL)milling represents a fundamental machining process for ***,the effects of electric field parameters,jet parameters,nozzle position,and milling parameters on milling performance remain unclear,which constrains the broad application of EMQL in aerospace *** study evaluated the milling performance of EMQL on nickel-based alloys using soybean oil as the lubrication *** revealed that compared with conventional pneumatic atomization MQL milling,EMQL reduced the milling force by 15.2%-15.9%,lowered the surface roughness by 30.9%-54.2%,decreased the average roughness spacing by 47.4%-58.3%,and decreased the coefficient of friction and the specific energy of cutting by 55%and 19.6%,*** optimization experiments using orthogonal arrays demonstrated that air pressure most significantly affected the milling force and specific energy of cutting,with a contribution rate of 22%,whereas voltage had the greatest effect on workpiece surface roughness,contributing 36.71%.Considering the workpiece surface morphology and the potential impact of droplet drift on environmental and health safety,the optimal parameter combination identified were a flow rate of 80 mL/h,an air pressure of 0.1 MPa,a voltage of 30 kV,a nozzle incidence angle of 35°,an elevation angle of 30°,and a target distance of 40 *** research aimed to provide technical insights for improving the surface integrity of aerospace materials that are difficult to machine during cutting operations.

关键词： electrostatic atomization MQL nickel-based alloys milling force surface roughness force model

Multipath Selection Algorithm Based on Dynamic Flow Prediction

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Journal of Computer and Communications 2024年第7期12卷 94-104页

作者： Jingwen Wang Guolong Yu xin cui School of Computer Science and Technology Shandong University of Technology Zibo China

Traditional traffic management techniques appear to be incompetent in complex data center networks, so proposes a load balancing strategy based on Long Short-Term Memory (LSTM) and quantum annealing by Software Defined Network (SDN) to dynamically predict the traffic and comprehensively consider the current and predicted load of the network in order to select the optimal forwarding path and balance the network load. Experiments have demonstrated that the algorithm achieves significant improvement in both system throughput and average packet loss rate for the purpose of improving network quality of service.

关键词： Data Center Network Software Defined Network Load Balance Long Short-Term Memory Quantum Annealing Algorithms

Mobility edges and localization characteristics in one-dimensional quasiperiodic quantum walk

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Chinese Physics B 2024年第6期33卷 156-160页

作者：崔鑫辉王慧敏李志坚 Institute of Theoretical Physics State Key Laboratory of Quantum Optics and Quantum DevicesShanxi UniversityTaiyuan 030006China

We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization *** inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the mobility edge, a critical energy to distinguish the energy regions of extended and localized states. The analytical solution of mobility edge is obtained by the Lyapunov exponents in global theory, and the consistency of the two indexes is confirmed. We further study the dynamic characteristics of the quantum walk and show that the probabilities are localized to some specific lattice sites with time evolution. This phenomenon is explained by the effective potential of the Hamiltonian which corresponds to the phase in the coin operator of the quantum walk.

关键词： quantum walk mobility edges quasiperiodicity

Review of Load Balancing Mechanisms in SDN-Based Data Centers

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Journal of Computer and Communications 2024年第1期12卷 49-66页

作者： Qin Du xin cui Haoyao Tang Xiangxiao Chen School of Computer Science and Technology Shandong University of Technology Zibo China

With the continuous expansion of the data center network scale, changing network requirements, and increasing pressure on network bandwidth, the traditional network architecture can no longer meet people’s needs. The development of software defined networks has brought new opportunities and challenges to future networks. The data and control separation characteristics of SDN improve the performance of the entire network. Researchers have integrated SDN architecture into data centers to improve network resource utilization and performance. This paper first introduces the basic concepts of SDN and data center networks. Then it discusses SDN-based load balancing mechanisms for data centers from different perspectives. Finally, it summarizes and looks forward to the study on SDN-based load balancing mechanisms and its development trend.

关键词： Software Defined Network Data Center Load Balancing Traffic Conflicts Traffic Scheduling

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道路网络多阶段抗灾能力优化模型构建与应用

浙江大学学报（工学版） 2024年第1期58卷 96-108页

作者：刘鹏路庆昌秦汉崔欣长安大学电子与控制工程学院陕西西安710064 大连海事大学航运经济与管理学院辽宁大连116026

为了降低路网抗灾成本并保障路网快速连通,研究道路交通网络多阶段灾害应对能力优化的问题.建立综合灾前应急工作站点选址和灾后路网恢复决策的3层规划模型,其中特别考虑了应急救援设施和后勤保障资源在耗尽性、运输方式和恢复作用上的... 详细信息

为了降低路网抗灾成本并保障路网快速连通,研究道路交通网络多阶段灾害应对能力优化的问题.建立综合灾前应急工作站点选址和灾后路网恢复决策的3层规划模型,其中特别考虑了应急救援设施和后勤保障资源在耗尽性、运输方式和恢复作用上的差异,定量建模了两者间的相互协作关系.通过综合双层遗传算法和FrankWolfe算法,获得模型的近似最优解.研究结果表明,与未考虑灾后恢复过程的灾前布设决策和未考虑后勤保障资源的灾前布设决策相比,最优决策可以分别降低10.96%的后勤保障资源运输成本和11.51%的加权恢复成本.后勤保障资源和应急救援设施布设数量共同影响路网的恢复效果,忽略两者间的协作关系,将会高估应急救援设施布设数量增加对恢复效果的影响.

关键词：交通工程道路交通网络抗灾能力优化 3层优化模型遗传算法