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Measuring Class Cohesion Based on Dependence Analysis

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Journal of Computer Science & Technology 2004年第6期19卷 859-866页

作者： Zhen-QiangChen Bao-WenXu yu-mingzhou DepartmentofComputerScienceandEngineering SoutheastUniversityNanjing210096P.R.China StateKeyLaboratoryofSoftwareEngineering WuhanUniversityWuhan430072P.R.China JiangsuInstituteofSoftwareQuality Nanjing210096P.R.China

Classes are the basic modules in object-oriented (OO) software, which consist of attributes and methods. Thus, in OO environment, the cohesion is mainly about the tightness of the attributes and methods of classes. This paper discusses the relationships between attributes and attributes, attributes and methods, methods and methods of a class based on dependence analysis. Then the paper presents methods to compute these dependencies. Based on these, the paper proposes a method to measure the class cohesion, which satisfies the properties that a good measurement should have. The approach overcomes the limitations of previous class cohesion measures, which consider only one or two of the three relationships in a class. Keywords cohesion - object-orientation - class - program complexity - dependence analysis Supported by the National Natural Science Foundation of China under Grant No.60073012; the National Basic Research 973 Program of China under Grant No.2002CB312000; the Program for Cross-Century Outstanding Teachers of the Ministry of Education; the National Research Foundation for the Doctoral Program of Higher Education of China under Grant No.20020286004; the Natural Science Foundation of Jiangsu, China, under Grant ***2001004; the Jiangsu Key Science and Technology Project under Grant ***2001025; the Opening Foundation of State Key Laboratory of Software Engineering in Wuhan University; the Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow University.Zheng-Qiang Chen was born in 1976. He received the M.S. and Ph.D. degrees in computer science in 2000 and 2003, respectively. His current research interests include program analysis, understanding and testing as well as other topics related to reverse engineering. He has published more than 30 technical papers.Bao-Wen Xu was born in 1961. He received the M.S. and Ph.D. degrees in computer science in 1984 and 2002, respectively. He is a professor in the

关键词： cohesion object-orientation class program complexity dependence analysis

Asymptotic behavior of the Taylor-expansion method of moments for solving a coagulation equation for Brownian particles

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Particuology 2014年第3期12卷 124-129页

作者： Zhongli Chen Jianzhong Lin mingzhou yu Zhejiang University China Jiliang University

The evolution equations of moments for the Brownian coagulation of nanoparticles in both continuum and free molecule regimes are analytically studied. These equations are derived using a Taylor-expansion technique. The self-preserving size distribution is investigated using a newly defined dimensionless parameter, and the asymptotic values for this parameter are theoretically determined. The dimensionless time required for an initial size distribution to achieve self-preservation is also derived in both regimes. Once the size distribution becomes self-preserving, the time evolution of the zeroth and second moments can be theoretically obtained, and it is found that the second moment varies linearly with time in the continuum regime. Equivalent equations, rather than the original ones from which they are derived, can be employed to improve the accuracy of the results and reduce the computational cost for Brownian coagulation in the continuum regime as well as the free molecule regime.

关键词： Brownian particles Coagulation Size distribution Accuracy

An analytical solution for the population balance equation using a moment method

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Particuology 2015年第1期13卷 194-200页

作者： mingzhou yu Jianzhong Lin Junji Cao Martin Seipenbusch Department of Physics China Jiliang University Institute of Earth Environment Chinese Academy of Sciences Institute for Mechanical Processes Engineering and Mechanics Karlsruhe Institute of Technology

Brownian coagulation is the most important inter-particle mechanism affecting the size distribution of aerosols. Analytical solutions to the governing population balance equation （PBE） remain a challenging issue. In this work, we develop an analytical model to solve the PBE under Brownian coagulation based on the Taylor-expansion method of moments. The proposed model has a clear advantage over conventional asymptotic models in both precision and efficiency. We first analyze the geometric standard deviation （GSD） of aerosol size distribution. The new model is then implemented to determine two analytic solu- tions, one with a varying GSD and the other with a constant GSD, The varying solution traces the evolution of the size distribution, whereas the constant case admits a decoupled solution for the zero and second moments, Both solutions are confirmed to have the same precision as the highly reliable numerical model, implemented by the fourth-order Runge-Kutta algorithm, and the analytic model requires significantly less computational time than the numerical approach. Our results suggest that the proposed model has great potential to replace the existing numerical model, and is thus recommended for the study of physical aerosol characteristics, especially for rapid predictions of haze formation and evolution,

关键词： Seif-preserving aerosols Analytical solution Taylor-expansion method of moments Population balance equation

Large eddy simulation of a planar jet flow with nanoparticle coagulation

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Acta Mechanica Sinica 2006年第4期22卷 293-300页

作者： mingzhou yu Jianzhong Lin Lihua Chen Tatleung Chan Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China China Jiliang University Hangzhou 310018 Research Centre for Combustion and Pollution Control Department of Mechanical Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

Coagulation and growth of nanoparticles subject to large coherent structures in a planar jet has been explored by using large eddy simulation. The particle field is obtained by employing a moment method to approximate the nanoparticle general dynamic equa- tion. An incompressible fluid containing particles of 1 nm in diameter is projected into a particle-free ambient. The results show that the coherent structures dominate the evolution of the nanoparticle number intensity, diameter and polydispersity distributions as the jet develops. In addition, the coherent structures act to increase the diffusion of particles, and the vortex rolling-up makes the particles distributing more irregularly while the vortex pairing causes particle distributions to become uniform. As the jet travels downstream, the time-averaged particle number concentration becomes lower in the jet core and higher in the outskirts, whereas the time- averaged particle mass over the entire flow field maintains unaltered, and the time-averaged particle diameter and geometric standard deviations grow and reach their maximum on the interface of the jet region and the ambient.

关键词： Nanoparticles Coagulation Planar jet Large eddy simulation Coherent structure

Intense and Superflat White Laser with 700-nm 3-dB Bandwidth and 1-mJ Pulse Energy Enabling Single-Shot Subpicosecond Pulse Laser Spectroscopy

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Research 2024年第2期6卷 319-327页

作者： Lihong Hong Haiyao Yang Liqiang Liu mingzhou Li yuanyuan Liu Baoqin Chen Huakang yu Wenbo Ju Zhi-yuan Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640China

An optical spectrometer is a basic spectral instrument that probes microscopic physical and chemical properties of macroscopic objects but generally suffers from difficulty in broadband time-resolved *** this work,we report the creation of ultrabroadband white-light laser with a 3-dB bandwidth covering 385 to 1,080 nm,pulse energy of 1.07 mJ,and pulse duration of several hundred femtoseconds by passing 3-mJ pulse energy,50-fs pulse duration Ti:Sapphire pulse laser through a cascaded fused silica plate and chirped periodically poled lithium niobate *** utilize this unprecedented superflat,ultrabroadband,and intense femtosecond laser light source to build a single-shot(i.e.,single-pulse)subpicosecond pulse laser ultraviolet-visible-near-infrared spectrometer and successfully measure various atomic and molecular absorption *** single-shot ultrafast spectrometer may open up a frontier to monitor simultaneously the ultrafast dynamics of multiple physical and chemical processes in various microscopic systems.

关键词： Pulse utilize frontier

Large Eddy Simulation of the Particle Coagulation in High Concentration Particle-Laden Planar Jet Flow

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 947-956页

作者： LIN Peifeng WU Dichong yu mingzhou WANG Chao ZHANG Lite ZHU Zefei Faculty of Mechanical Engineering ＆ Automation Zhejiang Sci-Tech University Hangzhou 310018 China Business Administration College Zhejiang University of Finance and Economics Hangzhou 310000 China Department of Physics China Jiliang University Hangzhou 310018 China School of Mechanical Engineering Hangzhou Dianzi University Hangzhou 310018 China

Particle coagulation by Brownian motion is an important but difficult research *** particle volume concentration is larger than 0.1%,the classic SMOLUCHOWSKI equation is not applicative *** high concentration coagulation,with HEINE＇s correction,source terms for the Taylor-series expansion method of moments（TEMOM） are firstly driven in this ***-fine particle（d0？100 mm） with initial volume fraction f？1% coagulation in a planar jet turbulence flow is simulated via the large eddy simulation（LES）.The instantaneous and time-averaged particle distributions and the high concentration enhancement are given *** particle number concentration distribution results show that the coagulation is more intense comparing to dilute case in previous research,especially near the nozzle *** jet flow is fully developed,the effect is much more obvious at the region between *** time-averaged γ（the high concentration enhance factor） distributes sharply and symmetrically about the jet centerline at the upstream,but becomes broad and flat at downstream where the cross-stream averaged γ fluctuates *** a new attempt,this paper shows Brownian coagulation with high concentration also can be calculated via TEMOM appropriately,and the coagulation at the region between vortexes is about 1.38 times intensive of the dilute result calculated by the classic Smoluchowski theory.

关键词： Coagulation LES Planar jet flow High concentration enhancement

Characterization particulate matter from several Chinese cooking dishes and implications in health effects

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Journal of Environmental Sciences 2018年第10期30卷 98-106页

作者： Lina Wang Xinran Zheng Svetlana Stevanovic Xin Wu Zhiyuan Xiang mingzhou yu Jing Liu State Environmental Protection Key Laboratory of Risk Assessment and Control on Chemical Process School of Resources and Environmental Engineering East China University of Science and TechnologyShanghai 200237 China International Laboratory of Air Quality and Health Queensland University of Science and TechnologyShanghai 200237 China The security environmental protection bureau of Ningbo daxie development zone Ningbo 315812 China Department of physics China Jiliang UniversityHangzhou 310018 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 250001 China

Cooking fume produced by oil and food at a high temperature releases large amount of fine particulate matter（PM） which have a potential hazard to human health. This chamber study investigated particle emission characteristics originated from using four types of oil（soybean oil, olive oil, peanut oil and lard） and different kinds of food materials（meat and vegetable）. The corresponding emission factors（EFs） of number, mass, surface area and volume for particles were discussed. Temporal variation of size-fractionated particle concentration showed that olive oil produced the highest number PM concentration for the entire cooking process. Multiple path particle dosimetry（MPPD） model was performed to predict deposition in the human respiratory tract. Results showed that the pulmonary airway deposition fraction was the largest. It was also found that particles produced from olive oil led to the highest deposition. We strongly recommend minimizing the moisture content of ingredients before cooking and giving priority to the use of peanut oil instead of olive oil to reduce human exposure to PM.

关键词： Chinese cooking Ultrafine particle Black carbon Emission factor Lung deposition

PABP-driven secondary condensed phase within RSV inclusion bodies activates viral mRNAs for ribosomal recruitment

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Virologica Sinica 2024年第2期39卷 235-250页

作者： Qiang Zhang Hanzhe Ye Cong Liu Haiwu Zhou Mingbin He Xiaodong Liang yu Zhou Kun Wang Yali Qin Zhifei Li mingzhou Chen State Key Laboratory of Virology and Modern Virology Research Center College of Life SciencesWuhan UniversityWuhan430072China Taikang Center for Life and Medical Sciences Wuhan UniversityWuhan430072China Hubei Jiangxia Laboratory Wuhan430200China

Inclusion bodies(IBs)of respiratory syncytial virus(RSV)are formed by liquid-liquid phase separation(LLPS)and contain internal structures termed“IB-associated granules”(IBAGs),where anti-termination factor M2-1 and viral mRNAs are ***,the mechanism of IBAG formation and the physiological function of IBAGs are ***,we found that the internal structures of RSV IBs are actual M2-1-free viral messenger ribonucleoprotein(mRNP)condensates formed by secondary ***,the RSV nucleoprotein(N)and M2-1 interact with and recruit PABP to IBs,promoting PABP to bind viral mRNAs transcribed in IBs by RNArecognition motif and drive secondary phase ***,PABP-eIF4G1 interaction regulates viral mRNP condensate composition,thereby recruiting specific translation initiation factors(eIF4G1,eIF4E,eIF4A,eIF4B and eIF4H)into the secondary condensed phase to activate viral mRNAs for ribosomal *** study proposes a novel LLPS-regulated translation mechanism during viral infection and a novel antiviral strategy via targeting on secondary condensed phase.

关键词： Respiratory syncytial virus(RSV) Inclusion bodies(IBs) Biomolecular condensates Liquid-liquid phase separation(LLPS) Secondary condensed phase mRNA activation

Distribution of non-spherical nanoparticles in turbulent flow of ventilation chamber considering fluctuating particle number density

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Applied Mathematics and Mechanics(English Edition) 2021年第3期42卷 317-330页

作者： Ruifang SHI Jianzhong LIN Hailin YANG mingzhouyu Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China College of Mechanical and Electrical Engineering China Jiliang UniversityHangzhou 310028China

The Reynolds-averaged general dynamic equation(RAGDE)for the nanoparticle size distribution function is derived,including the contribution to particle coagulation resulting from the fluctuating *** equation together with that of a turbulent gas flow is solved numerically in the turbulent flow of a ventilation chamber with a jet on the wall based on the proposed model relating the fluctuating coagulation to the gradient of mean *** results are compared with the experimental *** results show that the proposed model relating the fluctuating coagulation to the gradient of mean concentration is reasonable,and it is necessary to consider the contribution to coagulation resulting from the fluctuating concentration in such a *** changes of the particle number concentration M_(0) and the geometric mean diameter dg are more obvious in the core area of the jet,but less obvious in other *** the increase in the initial particle number concentration m00,the values of M_(0) and the standard deviation of the particle sizeσdecrease,but the value of d_(g) *** decrease in the initial particle diameter leads to the reduction of M_(0) andσand the increase in d_(g).With the increase in the Reynolds number,particles have few chances of collision,and hence the coagulation rate is reduced,leading to the increase in M_(0) andσand the decrease in d_(g).

关键词： non-spherical nanoparticle fluctuating particle concentration ventilation chamber particle distribution