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Efficient molecular model for squeeze-film damping in rarefied air

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Chinese Physics B 2019年第9期28卷 367-372页

作者： Cun-Hao Lu Pu Li Yu-ming fang School of Mechanical Engineering Southeast UniversityNanjing 211100China College of Electronic Science and Engineering Nanjing University of Posts and TelecommunicationsNanjing 211100China

Based on the energy transfer model(ETM) proposed by Bao et *** the Monte Carlo(MC) model proposed by Hutcherson and Ye, this paper proposes an efficient molecular model(MC-S) for squeeze-film damping(SQFD) in rarefied air by releasing the assumption of constant molecular velocity in the *** with the experiment data, the MC-S model is more efficient than the MC model and more accurate than ***, by using the MC-S model, the feasibility of the empirical model proposed by Sumali for SQFD of different plate sizes is *** is proved that, for various plate sizes, the accuracy of the empirical model is relatively *** last, the SQFD of various vibration frequencies is discussed, and it shows that, for low vibration frequency, the MC-S model is reduced to ETM.

关键词： micro-electro-mechanical system(MEMS) squeeze-film air damping rarefied air molecular model

THE ROLE FORE AIR FLOW IN SOIL SLOPE STABILITY ANALYSIS

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Journal of Hydrodynamics 2009年第5期21卷 640-646页

作者： ZHANG Xiao-yue ZHU Yue-ming fang Chun-hui College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

In order to investigate the effect of the pore air flow in the soil slope stability analysis, a water-air two-phase flow model, based on the multi-phase flow theory, is proposed and with the model, the water-phase and air-phase seepages of the soil slope in the stable seepage and rainfall situations are simulated. The soil slope safety coefficients are obtained according to the simulated pore air pressure and pore water pressure. The calculation results show that in the stable seepage situation, the influence of the pore air pressure on the soil slope stability can be neglected, while in the rainfall situation, the pore air pressure generated in the unsaturated zone will reduce the safety coefficient, and the larger the distance between the slip surface and the underground water level is, the greater the influence of the pore air pressure on the soil slope stability will be.

关键词： unsaturated soil water-air two-phase flow rainfall slope stability

Clinical significance of half-hepatic blood flow occlusion technology in patients with hepatocellular carcinoma with cirrhosis

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World Journal of Clinical Cases 2022年第24期10卷 8547-8555页

作者： Dong Liu Jian-ming fang Xian-Qi Chen Department of General Surgery Yongkang First People’s Hospital of Zhejiang ProvinceYongkang 321300Zhejiang ProvinceChina Department of Hepatopancreatobiliary Surgery Jinhua Guangfu Oncology HospitalJinhua 321000Zhejiang ProvinceChina

BACKGROUND Most patients with primary hepatocellular carcinoma(HCC)have a history of chronic hepatitis B and usually present with varying degrees of *** to the special nature of liver anatomy,the blood vessel wall in the liver parenchyma is thin and prone to *** bleeding and blood transfusion during hepatectomy are independent risk factors for liver cancer recurrence and *** clinical methods have been used to reduce intraoperative bleeding,and the Pringle method is most widely used to prevent blood flow to the *** To investigate the effect of half-hepatic blood flow occlusion after patients with HCC and cirrhosis undergo *** This retrospective study included 88 patients with HCC and liver cirrhosis who underwent hepatectomy in our hospital from January 2017 to September *** were divided into two groups based on the following treatment methods:the research group(n=44),treated with half-hepatic blood flow occlusion technology and the control group(n=44),treated with total hepatic *** in operation procedure,blood transfusion,liver function,tumor markers,serum inflammatory response,and incidence of surgical complications were compared between the *** The operation lasted longer in the research group than in the control group(273.0±24.8 min vs 256.3±28.5 min,P0.05).Before surgery,there were no significant differences in serum alanine transaminase(ALT),aspartate aminotransferase(AST),total bilirubin,and prealbumin levels between the research and control groups(P>0.05).Conversely,24 and 72 h after the operation the respective serum ALT(378.61±77.4

关键词： Hepatocirrhosis Hepatocellular carcinoma Hepatectomy Hepatic occlusion Liver function

Matching Boundary Conditions for Scalar Waves in Body-Centered-Cubic Lattices

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Advances in Applied Mathematics and Mechanics 2013年第3期5卷 337-350页

作者： ming fang Xianming Wang Zhihui Li Shaoqiang Tang Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterP.O.Box 211Mianyang 621000SichuanChina HEDPS CAPT and LTCSCollege of EngineeringPeking UniversityBeijing 100871China Center for Combustion Energy and Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Matching boundary conditions(MBC’s)are proposed to treat scalar waves in the body-centered-cubic *** matching the dispersion relation,we construct MBC’s for normal incidence and incidence with an angle *** of MBC operators then leads to multi-directional absorbing boundary *** effectiveness are illustrated by the reflection coefficient analysis and wave packet *** particular,the designed M1M1 treats the scalar waves in a satisfactory manner.

关键词： Body-centered-cubic(BCC)crystalline solids dispersion relation matching boundary condition reflection coefficient scalar waves

A New Humidity-Sensitive Material Based on PPBT Prepared with Palladium Complex Catalyst

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Chinese Chemical Letters 2000年第12期11卷 1097-1100页

作者： Hong Mei SUN Mu Jie YANG ming fang LING Department of Chemistry and Chemical Engineering Suzhou UniversitySuzhou 215006 Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027 Department of Information and Electronics Zhejiang UniversityHangzhou 310027

Soluble Poly(propargyl benzoate) (PPBT) with pi -conjugated structure was synthesized using a novel bis(triphenylphosphine)-bisacetylide palladium complex catalyst [Pd(PPh3)(2)(C equivalent to CCH2OOCPh)(2)] (PPB). An interdigital gold electrode was covered by screen printing films of doped PPBT (DPPBT) to prepare a resistance-type humidity sensor, which exhibits electrical response towards relative humidity (RH%) variations in the range 11%-96%. PPBT shows promise as a new humidity-sensitive material.

关键词： humidity-sensitive materials poly(propargyl benzoate) bis(triphenylphosphine)-bis-acetylide palladium complex resistance-type humidity sensor

Optimal Portfolio and Consumption Rule with a CIR Model Under HARA Utility

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Journal of the Operations Research Society of China 2018年第1期6卷 107-137页

作者： Chun-Feng Wang Hao Chang Zhen-ming fang College of Management and Economics Tianjin UniversityTianjin 300072China School of Science Tianjin Polytechnic UniversityTianjin 300387China

In the real-world environments,different individuals have different risk *** paper investigates the optimal portfolio and consumption rule with a Cox–Ingersoll–Ross(CIR)model in a more general utility *** consumption,an individual invests his wealth into the financial market with one risk-free asset and multiple risky assets,where the short-term rate is driven by the CIR model and stock price dynamics are simultaneously influenced by random sources from both stochastic interest rate and stock market *** individual hopes to optimize their portfolios and consumption rules to maximize expected utility of terminal wealth and intermediate *** preference of individual is assumed to satisfy hyperbolic absolute risk aversion(HARA)utility,which contains power utility,logarithm utility,and exponential utility as special *** using the principle of stochastic optimality and Legendre transform-dual theory,the explicit expressions of the optimal portfolio and consumption rule are *** sensitivity of the optimal strategies to main parameters is analysed by a numerical *** addition,economic implications are also *** research results show that Legendre transform-dual theory is an effective methodology in dealing with the portfolio selection problems with HARA utility and interest rate risk can be completely hedged by constructing specific portfolios.

关键词： CIR model Optimal portfolios and consumption rules HARA utility Legendre transform-dual theory Stochastic optimal control Economic implicati

Analysis on the time-domain characteristics of botnets control traffic

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 106-113页

作者： LI Wei-min MIAO Chen LIU fang LEI Zhen-ming School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Botnets are networks composed with malware-infect ed *** are designed and organized to be controlled by an *** victims are infected through their inappropriate network behaviors in most cases,the Internet protocol（IP） addresses of infected bots are ***,a bot can get an IP address through dynamic host configuration protocol（DHCP）,so they need to get in touch with the controller initiatively and they should attempt continuously because a controller can＇t be always *** whole process is carried out under the command and control（C＆C） *** goal is to characterize the network traffic under the C＆C channel on the time *** analysis draws upon massive data obtained from honeynet and a large Internet service provider（ISP） *** extract and summarize fingerprints of the bots collected in our ***,with the fingerprints,we use deep packet inspection（DPI） Technology to search active bots and controllers in the ***,we gather and analyze flow records reported from network traffic monitoring *** this paper,we propose a flow record interval analysis on the time domain characteristics of botnets control traffic,and we propose the algorithm to identify the communications in the C＆C channel based on our *** that,we evaluate our approach with a 3.4 GB flow record trace and the result is *** addition,we believe that our work is also useful information in the design of botnet detection schemes with the deep flow inspection（DFI） technology.

关键词： botnet detection netflow record time domain analysis deep flow inspection

Transparent Co_(3)FeO_(x) Film Passivated BiVO_(4) Photoanode for Efficient Photoelectrochemical Water Splitting

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Chinese Journal of Structural Chemistry 2021年第11期40卷 1505-1512,1409页

作者： fang ming QIN Qi CAI Qian LIU Wei Fujian Normal University Fuzhou 350007China CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Provincial Key Laboratory of NanomaterialFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Photoelectrochemistry that use semiconductors to absorb sunlight for water splitting provides an effective method for the development of renewable hydrogen energy in the *** this paper,a transparent and highly-efficient cobalt-iron oxide(Co_(3)FeO_(x))nano-film was fabricated through hydrothermal method by directional adjustment of atomic ratio to promote the kinetics of BiVO_(4)(BVO)photoanode water *** a result,the Co_(3)FeO_(x)-modified BVO photoanode(Co_(3)FeO_(x)/BVO)exhibits an impressive photocurrent density of 4.0 mA·cm^(2) at 1.23 V versus reversible hydrogen electrode(RHE),approximately 2.17-fold higher than that of bare BVO,as well as a cathodically shifted onset potential of 320 *** catalyst nanolayer structure is clarified by ultraviolet-visible *** addition,the Co_(3)FeO_(x)/BVO photoanode has better stability,and there is no obvious activity degradation after 10 hours of *** strategy provides a broad prospect for the use of water oxidation co-catalyst to achieve effective water splitting.

关键词： photoelectrochemical water splitting bismuth vanadate co-catalyst cobalt-iron oxide

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Flow Characteristics of Double-Cruciform Parachute at Inflating and Inflated Conditions

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 992-999页

作者： fang ming Sun Jianhong Zhang Tong Hou Bin Zhang Yantai Key Laboratory of Aircraft Environment Control and Life Support of MIIT College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics

The fluid-structure interaction (FSI) between the canopy and flow field on the inflating and inflated conditions is investigated based on the arbitrary Lagrange-Euler (ALE) method,in both a single-and double-cruciform parachute *** projection area of canopy is calculated in the inflation *** flow field characteristics and the interaction between canopies are *** showed that,with free stream velocity of 50m/s,overinflation phenomenon would not occur during the inflation process of the double-cruciform-parachute system,because the collision and extrusion of the two canopies during inflation obstructed the oscillation of the inner ***,compared with the single-cruciform parachute,the vortex motion in the wake of double-cruciform-parachute is more *** the double-cruciform parachute system oscillated at a velocity of 50 m/s with an angle of less than 6.8°.By comparison,the oscillation angle of the single-cruciform parachute was within 3.5° at the velocity of 50m/*** results are consistent with those of the wind tunnel test.

关键词： process of inflation arbitrary Lagrange-Euler(ALE) Lamb vector divergence cruciform parachute