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Joint optimization of LORA and spares stocks considering corrective maintenance time

Journal of Systems Engineering and Electronics 2015年第1期26卷 85-95页

作者： linhan Guo Jiujiu Fan Meilin Wen Rui Kang School of Reliability and Systems Engineering Beihang University

Level of repair analysis（LORA） is an important method of maintenance decision for establishing systems of operation and maintenance in the equipment development period. Currently, the research on equipment of repair level focuses on economic analysis models which are used to optimize costs and rarely considers the maintenance time required by the implementation of the maintenance program. In fact, as to the system requiring high mission complete success, the maintenance time is an important factor which has a great influence on the availability of equipment systems. Considering the relationship between the maintenance time and the spares stocks level, it is obvious that there are contradictions between the maintenance time and the cost. In order to balance these two factors, it is necessary to build an optimization LORA model. To this end, the maintenance time representing performance characteristic is introduced, and on the basis of spares stocks which is traditionally regarded as a decision variable, a decision variable of repair level is added, and a multi-echelon multiindenture（MEMI） optimization LORA model is built which takes the best cost-effectiveness ratio as the criterion, the expected number of backorder（EBO） as the objective function and the cost as the constraint. Besides, the paper designs a convex programming algorithm of multi-variable for the optimization model, provides solutions to the non-convex objective function and methods for improving the efficiency of the algorithm. The method provided in this paper is proved to be credible and effective according to the numerical example and the simulation result.

关键词： level of repair spares convex optimization multi-echelon multi-indenture(MEMI)

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Dynamically reconfigurable topological edge state in phase change photonic crystals

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Science Bulletin 2019年第12期64卷 814-822页

作者： Tun Cao linhan Fang Ying Cao Nan Li Zhiyou Fan Zhiguo Tao School of Optoelectronic Engineering and Instrumentation Science Dalian University of TechnologyDalian 116024China China North Vehicle Research Institute Beijing 100072China

The observation of topological edge states(TESs) revolutionized our understanding of scattering and propagation of electromagnetic(EM) waves. Supported by topological robustness, the TES at the interface between trivial and non-trivial insulators was not reflected from the structural disorders and imperfections. Recently topological photonic crystals(PhCs) were demonstrated to obtain remarkable one-way propagation of the TES, having the advantages of lossless propagation, dense integration, and high fabrication tolerance over conventional PhCs. Nevertheless, the lack of reversible switching of TES possesses significant limitations in helicity/spin filtering and tunable photonic devices. We proposed a topological PhC based on a prototypical phase-change material, Ge2 Sb2 Te5(GST225) to solve the problem. We find that at a particular frequency, the TES within the structure can be reversibly switched between "on"and "off" by transiting the GST225 structural state between amorphous and crystalline. Moreover, the topology of the PhC was maintained since the tuning of TES was achieved by varying the refractive index of GST225 instead of the structural geometry. This provides a continuous change of the spectral position of the photonic bandgap and TES by gradually crystallising the GST225. We show that the phase change of GST225 from amorphous to crystalline and vice versa can be engineered in nanoseconds. Our proof of concept may offer a platform for dynamically tuning the TESs that might otherwise be challenging to attain in photonic systems. We expect it to have potential applications for photonic devices in topological optical circuits and scatter-free one-way light propagation.

关键词： Phase change materials Photonic crystals Topological edge states Tunability Reconfigurability

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Advancements in heterojunction,cocatalyst,defect and morphology engineering of semiconductor oxide photocatalysts

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Journal of Materiomics 2024年第2期10卷 315-338页

作者： Guojing Wang Shasha Lv Yuanhua Shen Wei Li linhan Lin Zhengcao Li State Key Laboratory of New Ceramics and Fine Processing Key Laboratory of Advanced Materials(MOE)School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Beam Technology and Material Modification Ministry of EducationCollege of Nuclear Science and TechnologyBeijing Normal UniversityBeijing100875China School of Physical Science and Technology Lanzhou UniversityLanzhou730000China Department of Engineering Physics Tsinghua UniversityBeijing100084China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing100084China

Photocatalytic technology has emerged as a crucial avenue for harnessing solar energy,presenting itself as a viable solution to address the current energy crisis and environmental *** past 50 years have witnessed significant progress and breakthroughs in scientific research on photocatalytic *** paper provides a comprehensive review of the mechanism of photocatalytic technology and methods to improve the photocatalytic efficiency of semiconductor photocatalysts,such as TiO_(2) and *** this paper,common modification methods are divided into four categories:heterojunction con-struction,cocatalysts,defects,and morphological *** origin and development of photo-catalysts in each category are briefly summarized;moreover,the latest progress in each type of modification is discussed.S-scheme heterojunctions retain the high reduction and oxidation capacity of photogenerated electrons and holes by sacrificing half of the photogenerated carriers,showing excellent performance in photocatalysis and great application *** challenges associated with current modification schemes are *** is growing interest in quantitative and atomic-level modu-lation as attractive approaches to tackling these *** the electronic spin state and internal field is important for minimizing photogenerated carrier recombination in *** review will inspire researchers and promote the application of photocatalytic technology.

关键词： Photocatalytic activity Modification Heterostructure Thermal annealing Ion irradiation

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Ni元素质量分数对65Mn钢木工圆锯片性能的影响

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森林工程 2025年第1期41卷 67-74页

作者：赵俊博张雅繁何林韩张学瑾陈瑶高建民北京林业大学材料科学与技术学院北京100083

高质量、高效率的木材切削工艺对于提高木材资源的利用率以及提升木质产品的品质具有重要意义。目前,木工圆锯片常用钢材65Mn存在硬度和抗拉强度等力学性能欠佳的问题,为此通过添加镍(Ni)元素对65Mn钢进行改性。采用原料熔炼、浇筑试棒... 详细信息

高质量、高效率的木材切削工艺对于提高木材资源的利用率以及提升木质产品的品质具有重要意义。目前,木工圆锯片常用钢材65Mn存在硬度和抗拉强度等力学性能欠佳的问题,为此通过添加镍(Ni)元素对65Mn钢进行改性。采用原料熔炼、浇筑试棒、锻造加工以及热处理等步骤制备Ni改性65Mn钢,并对改性前后的65Mn钢进行显微硬度、冲击韧性和拉伸强度测试。同时运用金相显微镜(metallographic)及扫描电镜(SEM)剖析65Mn钢改性前后的组织构造差异。研究结果表明,1)添加Ni元素后,65Mn钢回火后的组织由回火屈氏体改变为淬火马氏体与回火马氏体的混合体,且当Ni元素质量分数达到0.9%时,出现残余奥氏体;2)在相同热处理工艺条件下,Ni元素对材料的硬度和抗拉强度的影响均呈现出先增大后降低的趋势,冲击韧性较未改性的65Mn钢有所降低。其中,添加质量分数为0.7%Ni元素的65Mn钢的硬度和抗拉强度最优,较未改性的65Mn钢分别增加了10.18%、35.40%(室温)。研究结果为后续木工圆锯片钢材的改良提供了新的思路和方法,有望推动木质加工工具行业的进一步发展。

关键词： 65Mn钢 Ni含量木工圆锯片力学性能

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Uncertain process-based data integration and residual lifetime evaluation of PCB in airborne equipment with ADT and field data

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Chinese Journal of Aeronautics 2024年第8期37卷 233-245页

作者： Yu WANG Rui KANG linhan GUO Xiaoyang LI Zhe LIU Xiaohui WANG Weifang ZHANG Schoool of Reliability and Systems Engineering Beihang UniversityBeijing 100191China

Accurately evaluating the lifespan of the Printed Circuit Board(PCB)in airborne equipment is an essential issue for aircraft design and operation in the marine atmospheric *** paper presents a novel evaluation method by fusing Accelerated Degradation Testing(ADT)data,degradation data,and life data of small samples based on the uncertainty degradation *** uncertain life model of PCB in airborne equipment is constructed by employing the uncertain distribution that considers the accelerated factor of multiple environmental conditions such as temperature,humidity,and *** addition,a degradation process model of PCB in airborne equipment is constructed by employing the uncertain process of fusing ADT data and field data,in which the performance characteristics of dynamic cumulative change are *** on minimizing the pth sample moments,an integrated method for parameter estimation of the PCB in airborne equipment is proposed by fusing the multi-source data of life,degradation,and *** engineering case illustrates the effectiveness and advantage of the proposed method.

关键词： Printed circuit board Degradation Data integration Field environment Accelerated degradation testing Parameter estimate

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Analysis and optimization of stamping and forming process of bearing outer ring

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 227-237页

作者： Shichao Zhu Yulu Ding Bing Long Hun Guo linhan Ouyang Wengang Chen Zhengyi Jiang College of Aeronautics and Mechanical Engineering Changzhou Institute of TechnologyChangzhou 213002China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China eering University of WollongongWollongong NSW 2522Australia

To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in ***-dimensionalmodels of the concave and convex dies were *** effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these ***,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of *** was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.

关键词： Plate stamping Bearing outer ring Mold design Optimization

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Experiment and simulation on the pyrite removal from the recirculating load of pulverizer with a dilute phase gas-solid fluidized bed

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International Journal of Mining Science and Technology 2013年第2期23卷 302-306页

作者： Wang Shuai He Yaqun He Jingfeng Ge linhan Liu Qing School of Chemical Engineering and Technology China University of Mining & Technology

In order to reduce the energy consumption and subsequent air pollution of coal-fired power station, based on the analysis to size and density distribution of particles from the recirculating load of the classifier of pulverizer, the separation experiment on sampling material from power plant with a dilute phase fluidized bed to remove pyrite and other minerals and numerical simulation on the separation process were done. The results show that the minimum fluidization velocity is 1.62 cm/s. Pyrite and other minerals in the material are separated. Ash of the upper and bottom layer material account for 33.34% and 73.42% respectively and sulfur content occupy 1.12% and 8.96% respectively. Scanning electron microscopy and spectroscopy tests show that sulfur in the bottom material exist in the form of pyrite. Numerical simulation on the flow field form of the dilute phase separation bed with gas-solid two phase and particle motion verifies the experimental results.

关键词： Pulverizer Recirculating load of classifier Dilute phase fluidized bed Pyrite Numerical simulation

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Photoswitchable quantum electrodynamics in a hybrid plasmonic quantum emitter

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Chip 2023年第3期2卷 67-74页

作者： Yuan Liu Hongwei Zhou Peng Xue linhan Lin Hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Beijing Computational Science Research Center Beijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

The design and preparation of quantum states free from environmen-tal decohering effects is critically important for the development of on-chip quantum systems with *** promising strategy is to harness quantum state superposition to construct decoherence-free subspace(DFS),which is termed dark ***,the exci-tation of dark states relies on anti-phase-matching on two qubits and the inter-qubit distance is of wavelength scale,which limits the de-velopment of compact quantum *** the current work,a hybrid plasmonic quantum emitter was proposed,which was composed of strongly correlated quantum emitters intermediated by a plasmonic *** turning the plasmonic loss from drawback into advantage,the anti-phase-matching rule was broken by rapidly de-caying the superposed bright state and preparing a sub-100 nm dark state with decay rate reduced by 3 orders of *** inter-estingly,the dark state could be optically switched to a single-photon emitter with enhanced brightness through photon-blockade,with the quantum second order correlation function at zero delay showing a wide range of tunability down to 0.02.

关键词： Decoherence-free subspace Plasmonics Quantum emitter On-chip quantum systems

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Opto-thermoelectric pulling of light-absorbing particles

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Light(Science & Applications) 2020年第1期9卷 1686-1696页

作者： linhan Lin Pavana Siddhartha Kollipara Abhay Kotnala Taizhi Jiang Yaoran Liu Xiaolei Peng Brian A.Korgel Yuebing Zheng Walker Department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA Materials Science&Engineering Program and Texas Materials Institute The University of Texas at AustinAustinTX 78712USA State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084People’s Republic of China McKetta Department of Chemical Engineering The University of Texas at AustinAustinTX 78712USA Department of Electrical and Computer Engineering The University of Texas at AustinAustinTX 78712USA

Optomechanics arises from the photon momentum and its exchange with low-dimensional *** is well known that optical radiation exerts pressure on objects,pushing them along the light ***,optical pulling of an object against the light path is still a counter-intuitive ***,we present a general concept of optical pulling-opto-thermoelectric pulling(OTEP)—where the optical heating of a light-absorbing particle using a simple plane wave can pull the particle itself against the light *** irradiation orientation-directed pulling force imparts self-restoring behaviour to the particles,and three-dimensional(3D)trapping of single particles is achieved at an extremely low optical intensity of 10^(−2)mWμm^(−2).Moreover,the OTEP force can overcome the short trapping range of conventional optical tweezers and optically drive the particle flow up to a macroscopic *** concept of selfinduced opto-thermomechanical coupling is paving the way towards freeform optofluidic technology and lab-on-achip devices.

关键词： absorbing light trapping

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An information fusion FMEA method to assess the risk of healthcare waste

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Journal of Management Science and Engineering 2021年第1期6卷 111-124页

作者： linhan Ouyang Yige Zhu Wei Zheng Lin Yan Department of Management Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina

Healthcare waste(HCW)management plays a vital role in the development of modern *** HCW management,failure mode and effects analysis(FMEA)is a popular method to implement risk management for improving the quality of ***,the shortcomings of the traditional FMEA method have been widely discussed in *** paper proposes an information fusion FMEA method based on 2-tuple linguistic information and interval *** 2-tuple linguistic set theory is adopted to change the heterogeneous information into interval ***,the interval probability comparison method is applied to analyze failure ***,a case study is presented to verify the reliability and effectiveness of the proposed method by comparing different FMEA methods.

关键词： Healthcare waste management Failure mode and effect analysis Heterogeneous information fusion Interval probability

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