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Operational Risk-averse Routing Optimization for Cyber-physical Power Systems

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CSEE Journal of Power and Energy Systems 2022年第3期8卷 801-811页

作者： Baozhong Ti Jianxiao Wang Gengyin Li ming zhou State Key Laboratory of Alternate Electrical Power System with Renew-able Energy Sources North China Electric Power UniversityBeijing 102206China

The extensive application of modern information and communication technology in the power system through the in-depth integration of the information system and the power system has led to the gradual development of the cyberphysical power system(CPPS).While advanced information technology increases the safety and reliability of power system operations,it also increases the risks of fault *** improve the reliability of CPPS from the perspective of power communication routing,it is proposed that the CPPS model and vulnerability assessment of power node reflect the correlation between information and energy flows with the service impact on power grid operation,which is an important index for evaluating communication *** to the distribution of services at the different important levels on the links,the importance of the cross-layer link is established as the vulnerability evaluation index of the communication ***,the routing optimization model is proposed in combination with the service transmission risk under cyber-attack and the operating characteristics of the information system,which is solved through an improved fast-convergent genetic *** simulation results show that the proposed method allocates the alternate route to the low-risk link without significantly increasing the delay of the main route,which effectively improves the power supply reliability of CPPS in extreme cyber-attack scenarios.

关键词： Comprehensive balanced degree cross-layer link importance cyber-attack cyber-physical power system routing optimization model service importance

A new closed-form method for inertia force and moment calculation in reciprocating piston engine design

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Science China(Technological Sciences) 2018年第6期61卷 879-885页

作者： XIE ZhiFeng XU QuanYong GUAN NanXiang zhou ming Institute for Aero-Engine School of Aerospace Engineering Tsinghua University Beijing 100084 China

The piston crank mechanism is an important component of a reciprocating piston engine. It is an inherent vibration system, and as such, the calculation of unbalance quantity is a critical procedure in balancing mechanism design, which is adopted to balance inertia loading. The traditional method usually applies a Taylor series expansion with the crank-conrod ratio, then a Fourier transform with the crank angle. The Taylor expansion generally ignores the influence on calculations resulting from the high order terms. However, the high order terms of the Taylor expansion will also contribute to the low order terms in the Fourier series. This will induce poor precision in the inertia loading calculation, especially in a high crank-conrod ratio engine. Thus, this paper proposes a new closed-form method, which only adopts a Fourier transformation for the calculation. The coefficients of the Fourier transformation terms contain the contributions of all order terms of the crank-conrod ratio. Therefore, we named it as a closed-form method. Compared with the traditional method, the closed-form method improves the numerical accuracy of the secondary reciprocating inertia force by 1.5%–4%, when the crank-conrod ratio varies from 0.25 to 0.4. Using this new closedform method to design a balancing mechanism, the primary and secondary reciprocating inertia forces can be completely balanced. For an engine, where the primary and secondary inertia forces are balanced, the ratio of the residual inertia force to the total inertia force using the traditional method is 1.5%, while the ratio decreases to 0.5% using the closed-form method. The closed-form method is independent of engine configurations, including centric and eccentric engines, and single and multicylinder engines. Examples of applications using the proposed method are provided.

关键词： piston engine balance inertia loading closed-form vibration

Aeroelastic simulation of the first 1.5-stage aeroengine fan at rotating stall

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Chinese Journal of Aeronautics 2020年第2期33卷 529-549页

作者： Feng LIANG Zhifeng XIE Aiguo XIA ming zhou School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Beijing Aeronautical Technology Research Center Beijing 100076China

A massive parallel aeroelastic simulation platform has been built to investigate the first1.5-stage fan of an aeroengine at rotating *** Computational Fluid Dynamics(CFD)solver and Computational Structural Dynamics(CSD)solver are coupled directly by non-matching mesh *** unsteady rotor/stator interaction is solved by the Sliding Mesh Interface *** original rotor blades are shrouded by the midspan *** unshrouded fan is also created to investigate the effects of the midspan *** the shrouded fan and unshrouded fan have stable aeroelasticity at the designed *** rotating stall,the stalled region rotates at 30%of the rotor speed on the absolute reference *** energy spectrum of the rotating stalled flow is measured *** shows that the first two order excitations are much stronger than the higher order *** the flow of rotating stall,the fifth backward travelling wave mode of shrouded fan is resonated by the fifth excitation of the rotational stalled flow because the rotational speed of the stalled region coincides with the modal rotational speed,while for the unshrouded fan,the first bending mode is resonated by the second excitation of the rotational stalled flow,forming two waves in the circumference of the annulus *** rotating stall,the vibration of the shrouded blades is still under control but the vibration of the unshrouded blades is diverged and out of control.A novel tool,i.e.,resonance map,is proposed to predict the *** provides a perspective to explain the effects of midspan shrouds at a theoretical level,and it would also be helpful in the structural design of blades.

关键词： Aeroelasticity Computational Fluid Dynamics Midspan shrouds Rotating stall Turbomachine blades

An efficient three-dimensional foil structure model for bump-type gas foil bearings considering friction

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Friction 2021年第6期9卷 1450-1463页

作者： Yongpeng GU Xudong LAN Gexue REN ming zhou School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper presents an efficient three-dimensional(3D)structural model for bump-type gas foil bearings(GFBs)developed by considering *** foil structures are modeled with a 3D shell finite element *** the bump foil mechanical characteristics,the Guyan reduction and component mode synthesis methods are adopted to improve computational efficiency while guaranteeing accurate static responses.A contact model that includes friction and separation behaviors is presented to model the interactions of the bump foil with the top foil and bearing *** proposed structural model was validated with published analytical and experimental *** coupled elastohydrodynamics model of GFBs was established by integration of the proposed structural model with data on hydrodynamic films,and it was validated by comparisons with existing experimental *** performance of a bearing with an angular misalignment was studied numerically,revealing that the reaction torques of the misaligned bearing predicted by GFB models with 2D and 3D foil structure models are quite *** 3D foil structure model should be used to study GFB misalignment.

关键词： gas foil bearing bump foil model frictional contact elastohydrodynamics bearing misalignment

Preferential oxidation of CO in excess H_2 over CeO_2/CuO catalyst:Effect of calcination temperature

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Journal of Natural Gas Chemistry 2012年第5期21卷 513-518页

作者： Zhiming Gao ming zhou Hao Deng Yong Yue Key Laboratory of Cluster Science Ministry of Education of China School of Chemistry Beijing Institute of TechnologyBeijing 100081China Research Department of Environmental Technology CNPC Research Institute of Safety and Environmental TechnologyBeijing 100083China

Different from the classical configuration CuO/CeO2 catalyst,the inverse configuration CeO2 /CuO catalyst （atomic ratio of Ce/Cu=10/100） was prepared by impregnation *** calcination temperatures were selected to investigate the interaction between CeO2 and CuO *** is found that as calcination temperature increased from 500 to 900 C,sintering of CeO2 particles on the support occurred together with the diffusion of a portion of Ce 4＋ ions into CuO crystals,forming solid *** of interface complex Ce-O-Cu was suggested by TPR *** catalyst calcined at 700 C gives the highest activity for preferential oxidation of CO in excess H2 stream.

关键词： preferential oxidation carbon monoxide cerium oxide cupric oxide TPR

An improved electrochemiluminescence polymerase chain reaction method for the detection of Fusarium wilts

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Chinese Chemical Letters 2008年第8期19卷 959-961页

作者： Jie Wei Xiao ming zhou MOE Key Laboratory of Laser Life Science ＆ Institute of Laser Life Science South China Normal University Guangzhou 510631 China

An improved electrochemiluminescence polymerase chain reaction （ECL-PCR） method was developed and applied to detect Fusarium wilt. Briefly, the internal transcribed spacer （ITS） sequence of Fusarium oxysporumf, sp Cubense （FOC） was amplified by PCR. Two universal fragments, which were complimentary to Ru（bpy）3^2＋（TBR） labeled probe and Biotin labeled probe, respectively, were connected to the tail of primers so that all the PCR products got universal sequences. Then biotin labeled probes and TBR labeled probes were hybridized with the PCR products at the same time. Through the specific interaction between biotin and streptavidin, the PCR products were captured by streptavidin coated magnetic bead and then detected by ECL assay. The experiment results showed that the healthy banana samples and infected ones can be discriminated by this ECL-PCR method. This improved ECL-PCR approach is useful in Fusarium wilt detection due to its high sensitivity, simplicity and stability.

关键词： Electrochemiluminescence Polymerase chain reaction Fusarium wilts

Detection of telomerase activity by combination of telomeric repeat amplification protocol and electrochemiluminescence assay

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Chinese Chemical Letters 2008年第6期19卷 699-702页

作者： Xiao ming zhou Li Jia MOE Key Laboratory of Laser Life Science ＆ Institute of Laser Life Science South China Normal University Guangzhou 510631 China

A highly sensitive telomerase detection method that combines telomeric repeat amplification protocol （TRAP） and magnetic beads based electrochemiluminescence （ECL） assay has been developed. Briefly, telomerase recognizes biotinylated telomerase synthesis primer （B-TS） and synthesizes extension products, which then serve as the templates for PCR amplification using B-TS as the forward primer and tris-（2′2′-bipyridyl） ruthenium （TBR） labeled ACX （TBR-ACX） as the reversed primer. The amplified product is captured on streptavidin-coated paramagnetic beads and detected by ECL. Telomerase positive HeLa cells were used to validate the feasibility of the method. The experimental results showed down to 10 cancer cells can be detected easily. The method is a useful tool for telomerase activity analysis due to its sensitivity, rapidity, safety, high throughput, and low cost. It can be used for screening a large amount of clinical samples.

关键词： Telomerase activity TRAP Electrochemiluminescence Cancer diagnosis

State-of-the-art advancements of transition metal oxides as photoelectrode materials for solar water splitting

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Rare Metals 2022年第7期41卷 2370-2386页

作者： Gai-Li Ke Bi Jia Hui-Chao He Yong zhou ming zhou State Key Laboratory of Environmental-Friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010China Institute of Environmental Energy Materials and Intelligent Devices School of Metallurgy and Materials EngineeringChongqing University of Science and TechnologyChongqing 401331China Ecomaterials and Renewable Energy Research Center School of PhysicsNanjing UniversityNanjing 211102China Department of Chemistry State University of New YorkBinghamton NY 13902USA

Photoelectrochemical(PEC)water splitting can convert renewable solar energy into clean hydrogen *** are the core components of water-splitting *** the past 40 years,a series of binary and ternary transition metal oxides have been investigated as photo-electrode materials for solar water splitting,and numerous studies have been carried out to modify their water-split-ting *** satisfactory transition metal oxide photoelectrode materials have not been found,it is necessary to summarize the recent advancements in tran-sition metal oxide photoelectrode materials to guide future *** this review,the background and principle of PEC water splitting are *** semiconductor properties and modification progress of typical binary and ternary metal oxide photoanodes and photocathodes for solar water splitting are *** on the newly developed strategies in recent years,a brief outlook is presented for efficient PEC water splitting using transition metal oxide photoelectrodes.

关键词： Transition metal oxides Photoanodes Photocathodes Water splitting Review

Multi-Location Investigation of Optimum Planting Density and Boll Distribution of High-Yielding Cotton (*** L.) in Hubei Province,China

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Agricultural Sciences in China 2010年第12期9卷 1749-1757页

作者： YANG Guo-zheng zhou ming-yan College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 P.R.China Crop Production Department Agricultural Division of Hubei Province Wuhan 430070 P.R.China

Cotton yield per unit ground area has stagnated for a dozen years in Hubei Province, China, although a series of new high- yielding varieties have been commercialized. A multi-location investigation was carried out in 2008 and 2009 in 13 counties to determine if increased planting population density （PPD） would break the stagnant yield. The results showed that significant differences among the fields existed in theoretical yield, PPD, and bolls per square meter （BPM）. The lowest yield of 1 641.1 kg ha-I was resulted from the lowest PPD of 1.7 plants m-2 and the lowest BPM of 71.8 bolls m-2, while the highest yield of 2 779.7 kg ha-~ was resulted from the highest PPD of 2.5 plants m-2, and the highest BPM of 129.4 bolls m-z. Plant mapping revealed that boll retention rate （BRR） was maintained over 30 or 40% for the first 17-18 fruiting branches （FBs） and decreased dramatically thereafter, rotten boll rate （RBR） decreased, but open boll rate （OBR） rose first and dropped later with rising FB from the bottom to the top. But BRR, RBR, and OBR were all dropped with the fruiting positions （FPs） extending outwards. The optimum range of plant density would be 2-3 plants m-2 and the proper individual plant structure would be 16-19 FBs with 5-7 FPs for cotton production in Hubei Province.

关键词： cotton (Gossypium hirsutum L.) planting population density (PPD) lint yield boll retention rate (BRR)