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Approximate Approach to Deal with the Uncertainty in Integra ted Production Scheduling and Maintenance Planning

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 106-117页

作者： cui weiwei School of Management Shanghai UniversityShanghai 200444China

This paper deals with the integration problem between production scheduling and maintenance planning in a single machine,where the impact of failure uncertainty is *** objective is to minimize the weighted sum of quality robustness and solution robustness,which is determined by the jobs1 sequence,preventive maintenances,position and buffer time in the ***,a three-stage algorithm is devised to solve the problem,where the gradient descent algorithm based on an effective surrogate measure is developed in the second st *** numerical experiments show that the deviation of the approximate approach is very small,as compared with the exact solution obtained by *** balance between quality robustness and solution robustness and the distribution of buffer time in different scenarios are shown in a case *** validates the necessity and effectiveness of the consideration of robustness in the industrial practice.

关键词： production scheduling maintenance policy proactive uncertainty

A Novel Nano/Micro-Fibrous Scaffold by Melt-Spinning Method for Bone Tissue Engineering

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Journal of Bionic Engineering 2015年第1期12卷 117-128页

作者： Liguo cui Ning Zhang weiwei cui Peibiao Zhang Xuesi Chen Key Laboratory of Polymer Ecobiomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100039 China Department of Bone and Joint Surgery First Hospital of Jilin University Changchun 130021 China School of Public Health Jilin University Changchun 130021 China

In order to architecturally and functionally mimic native Extracellular Matrix （ECM）, a novel micro/nano-fibrous scaffold of hydroxyapetite/poly（lactide-co-glycolide）（HA/PLGA） composite was successfully prepared by melt-spinning method. A porous three-dimensional scaffold fabricated by melt-molding particulate-leaching method was used as control. This kind of scaffold comprising both nanofiber and microfiber had an original structure including a nano-network favorable for cell adhe- sion, and a micro-fiber providing a strong skeleton for support. The microfibers and nanofibers were blended homogeneously in scaffold and the compression strength reached to 6.27 MPa, which was close to human trabecular bone. The typical mi- cro/nano-fibrous structure was more benefcial for the proliferation and differentiation of Bone Mesenehymal Stem Cells （BMSCs）. The calcium deposition and Alkaline Phosphatase （ALP） activity were evaluated by the differentiation of BMSCs, and the results indicated that the temporary ECM was very beneficial for the differentiation of BMSCs into maturing osteoblasts. For repairing rabbit radius defects in vivo, micro/nano-fibrous scaffold was used for the purpose of rapid bone remodeling in the defect area. The results showed that a distinct bony callus of bridging was observed at 12 weeks post-surgery and the expression of osteogenesis-related genes （bone-morphogenetic protein-2, Osteonectin, collagen-I） increased because of the ECM-like structure. Based on the results, the novel micro/nano-fibrous scaffold might be a promising candidate for bone tissue engi- neering.

关键词： PLGA-based scaffold melt-spinning nano/micro-fibers bone tissue engineering

A New Approach to Suppress Tip Leakage Flow Utilizing Induced Shock Wave in Tip Region of a TransonicCompressor Rotor

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Journal of Thermal Science 2024年第6期33卷 2059-2074页

作者： cui weiwei YAO Fei LI Zongming WANG Xiaonan CHANG Guozhang WANG cuiping College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Clean energy laboratory Shandong University of Science and TechnologyQingdao 266590China

Tip leakage flow affects the flow stability of high-loading compressors ***,a novel approach via induced shock wave near suction-side edge of blade tip was proposed to suppress the strength and influence range of leakage flow in a transonic *** new schemes with different circumferentially diverging degrees of clearance were designed to reveal the mechanism of the new *** the action of the circumferentially diverging clearance(from the pressure side to the suction side over blade tip),a much more dramatic acceleration of the supersonic leakage jet flow appeared over blade tip of the new *** induced shock wave was produced near the suction side edge of blade tip due to the pressure difference between the discharging leakage flow and the surrounding high-pressure mainflow in tip *** a result,both the mass flow rate and the outlet velocity of leakage flow were reduced significantly via the induced shock ***,the suppressing effect of the new approach on the tip leakage jet flow was closely related to the strength and circumferential location of the induced shock *** the aids of the induced shock wave,the largest improvement of tip flow characteristics with an over 5%increase in stall margin was realized in new transonic rotor when the circumferential divergence angle equals 8°,accompanied with no more than a 0.4%decrease in isentropic efficiency.

关键词： circumferentially diverging clearance induced shock wave leakage flow low-velocity region st marginenhancement

Theoretical and experimental characterizations of gigahertz acoustic streaming in microscale fluids

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Nanotechnology and Precision Engineering 2019年第1期2卷 15-22页

作者： weiwei cui Wei Pang Yang Yang Tiechuan Li Xuexin Duan State Key Laboratory of Precision Measuring Technology & Instruments College of Precision Precision Instrument and Optoelectronics Engineering Tianjin University

Even as gigahertz(GHz) acoustic streaming has developed into a multi-functional platform technology for biochemical applications, including ultrafast microfluidic mixing, microparticle operations, and cellar or vesicle surgery, its theoretical principles have yet to be established. This is because few studies have been conducted on the use of such high frequency acoustics in microscale fluids. Another difficulty is the lack of velocimetry methods for microscale and nanoscale fluidic streaming. In this work, we focus on the basic aspects of GHz acoustic streaming,including its micro-vortex generation principles, theoretical model, and experimental characterization technologies. We present details of a weak-coupled finite simulation that represents our current understanding of the GHz-acoustic-streaming phenomenon. Both our simulation and experimental results show that the GHzacoustic-induced interfacial body force plays a determinative role in vortex generation. We carefully studied changes in the formation of GHz acoustic streaming at different acoustic powers and flow rates. In particular,we developed a microfluidic-particle-image velocimetry method that enables the quantification of streaming at the microscale and even nanoscale. This work provides a full map of GHz acoustofluidics and highlights the way to further theoretical study of this topic.

关键词： Acoustic streaming Gigahertz Body force Microfluidic PIV

Low power consumption driving technique for FCD based on LC resonance

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Radiation Detection Technology and Methods 2024年第2期8卷 1272-1279页

作者： Ziliang Zhang weiwei cui Yuxuan Zhu Yong Chen Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadShijingshan DistrictBeijing100049China University of Chinese Academy of Sciences Beijing100049China

Purpose The purpose is to reduce the power consumption of FCD array without changing the performances of the detector *** The traditional FCD driver circuit adopts push-pull configuration output structure *** the drive circuit outputs high level voltage,it will charge the pixel capacitance of the ***,at the low output level,the charge on the capacitor will be shorted to *** paper utilizes an LC resonance driving *** the FCD is drived by low-level voltage,the charge on the pixel capacitor will not be shorted to the ground,instead the charge are transfer and stored on the inductor and will be reused when the FCD is drived by the high-level *** Based on this principle,we design a new FCD driver *** can effectively reduce the power consumption up to 70%.We also compare the X-ray energy resolution of this new driver circuit to that of normal driver *** normal driver circuit,the energy resolution is 228 eV@8.04 keV and the charge transfer efficiencies is 0.99994,in this new driver circuit,the energy resolution is 256 eV@8.04 keV and the charge transfer efficiencies becomes *** There is no substantial change in energy resolution and it meets our requirements in space application *** addition,the new driver circuit is stable and easy to implement.

关键词： FCD Power-saving LC resonance

Effects of Width Variation of Pressure-Side Winglet on Tip Flow Structure in a Transonic Rotor

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Journal of Thermal Science 2022年第1期31卷 141-150页

作者： cui weiwei WANG Xinglu YAO Fei ZHAO Qingjun LIU Yuqiang LIU Leinan WANG cuiping YANG Laishun College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China Key Laboratory of Civil Engineering Disaster Prevention and Mitigation of Shandong Province Qingdao 266590China Clean Energy Laboratory Shandong University of Science and TechnologyQingdao 266590China

Tip leakage flow has become one of the major triggers for rotating stall in tip region of high loading transonic compressor *** with active flow control method,it’s wise to use blade tip modification to enlarge the stable operating range of ***,three pressure-side winglets with the maximum width of 2.0,2.5 and 3.0 times of the baseline rotor,are designed and surrounded the blade tip of NASA rotor 37,and the three new rotors are named as RPW1,RPW2,and RPW3 *** numerical results show that the width of pressure-side winglet has significant influence on the stall margin and the minimum throttling massflow of rotor,while it produces less effect on the choking massflow and the peak efficiency of new *** the width of the pressure-side winglet increases from new rotor RPW1 to RPW3,the strength of leakage massflow has been attenuated dramatically and a reduction of 20%in leakage massflow rate has appeared in the new rotor *** contrast,the extended blade tip caused by winglet has not introduced much more aerodynamic losses in tip region of rotor,and the new rotors with different width of pressure-side winglet have the similar peak efficiency to the *** new shape of the leakage channel over blade tip which replaces of the static pressure difference near blade tip has dominated the behavior of the leakage flow in tip *** both the new aerodynamic boundary and throat in tip gap have reshaped by the low-velocity flow near the solid wall of extended blade tip,the discharging velocity and massflow rate of leakage flow have been suppressed obviously in new *** addition,the increasing inlet axial velocity at the entrance of new rotor has increased slightly as well,which is attributed to the less blockage in the tip region of new *** consideration of the increased inlet axial velocity and the weakened leakage flow,the new rotor presents an appropriately linear increase of the stall margin when the width of pressure-

关键词： pressure-side winglet blade tip aerodynamic losses leakage channel stall margin

Pyrolyzing soft template-containing poly(ionic liquid)into hierarchical N-doped porous carbon for electroreduction of carbon dioxide

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Chinese Journal of Chemical Engineering 2022年第3期35卷 192-201页

作者： Mingdong Sun Zhengyun Bian weiwei cui Xiaolong Zhao Shu Dong Xuebin Ke Yu Zhou Jun Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China Department of Chemical Engineering University of HullHull HU67RXUnited Kingdom

Heteroatom-doped carbon materials have demonstrated great potential in the electrochemical reduction reaction of CO_(2)(CO_(2)RR)due to their versatile structure and ***,rational structure control remains one *** this work,we reported a unique carbon precursor of soft template-containing porous poly(ionic liquid)(PIL)that was directly synthesized via free-radical self-polymerization of ionic liquid monomer in a soft template *** of the carbonization temperature in a direct pyrolysis process without any additive yielded a series of carbon materials with facile adjustable textural properties and N ***,the integration of soft-template in the PIL precursor led to the formation of hierarchical porous carbon material with a higher surface area and larger pore size than that from the template-free *** CO_(2)RR to CO,the champion catalyst gave a Faraday efficiency of 83.0%and a current density of 1.79 mA·cm^(-2)at-0.9 V *** hydrogen electrode(***).The abundant graphite N species and hierarchical pore structure,especially the unique hierarchical small-/ultramicropores were revealed to enable better CO_(2)RR performance.

关键词： CO_(2)RR Poly(ionic liquid) N-doped carbon materials Pore diameter Hierarchical pore

Effect of Geometric Variation of Root Fillet on the Flow Characteristic of a Transonic Compressor Rotor

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Journal of Thermal Science 2023年第4期32卷 1407-1420页

作者： cui weiwei LIU Yuqiang LIU Fusong YANG Laishun LI Longting YAO Fei WANG Xinglu WANG cuiping College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao266590China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China Clean energy laboratory Shandong University of Science and TechnologyQingdao266590China

The effects of root fillet on the flow behavior of high loading compressor rotor tends to be much more crucial in practice,and it’s necessary to explore the internal relations between the geometric effects of root fillet and the flow behaviors of rotor ***,eight types of root fillet with different radius were designed and installed around the blade root of NASA *** the aids of fillet,the corner separation near suction side of blade root has been suppressed significantly in that the root fillet reconstructs the circumferential bending distributon of the suction-side curve from leading edge to trailing edge,and reduces the genmetric turning angle in the latter part of root section near trailing ***,apart from the improvement of corner flow characteristic caused by root fillet,both the tip flow deterioration and the decrease of stall margin occur in the new rotors,which indicates an indirect correlation between tip flow characteristic and root fillet exists indeed in the three-dimensional flowfields of transonic ***,by means of the new radial pressure equilibrium affected by root fillet,a larger radius of root fillet contributes to much larger blade loading and stronger leakage flow in tip region of compressor *** a result,a monotonic decrease of stall margin was present in the transonic rotor with increase of the root fillet ***,the positive bending of blade tip was introduced to deal with the negative effect caused by the root fillet *** with the effects of root fillet and positive tip-bending on the radial pressure equilibrium existing in channels,both the radial and streamwise loading distributions tend to be much more reasonable in new rotors,and the static pressure difference in former 1/3 chord of blade tip has decreased clearly which benefits to reduce the strength of leakage flow in tip ***,the flow deterioration in tip region of transonic rotor induced by root fillet ha

关键词： root fillet variation corner separation radial pressure equilibrium stall margin positive tip-bending

Determination of HCH and DDT in soils following Wenchuan 5.12 Violent Earthquake in China

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Chinese Journal Of Geochemistry 2011年第1期30卷 125-131页

作者： cui weiwei ZHANG Qiangbin ZHU Xianlei WAN Yunyang ZHANG Zhihuan FAN Zhihua WANG Tieguan College of Geosciences China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Department of Environmental and Occupational Medicine University of Medicine and Dentistry of NJ-Rutgers University Piscataway NJ 08854 USA

A large number of disinfectants and insecticides were used on a large scale after the Wenchuan 5.12 Violent Earthquake. The disinfectants and insecticides, including HCH (hexachlorocyclohexane) and DDT (dichlorodiphenyltrichoroethane) as representative OCPs, could lead to serious environmental problems. In order to disclose the residues of HCH and DDT in soils following the Wenchuan 5.12 Violent Earthquake, surface soils in Dujiangyan City and Beichuan County were sampled in 2009. The samples were analyzed by GC/MS after pre- treatment by ultrasonic solvent extraction. It has been found that the concentra-tions of γ-HCH, β-HCH and 4,4'-DDT in soils of Beichuan County were 94–102.4, 14.1–36.1 and 2.9–4.3 times high their concentrations in those of the Wolong Nature Reserve, and the concentrations in soils of Dujiangyan City were 52.4–61.6, 8.8 –45.3 and 5.4–6.2 times high their concentrations in soils of the Wolong Nature Reserve, respectively. According to the isomers of HCHs and metabolites of DDTs, it could be concluded that these areas may have additional inputs of lindane and 4,4'-DDT.

关键词：表层土壤强烈地震六六六滴滴涕汶川卧龙自然保护区六氯环己烷中国