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Recent Advances in Research of the Distributed Parameters Control System with Moving Boundary

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Journal of Systems Engineering and Electronics 1993年第3期4卷 47-61页

作者： Yang, Xueshi Yu, Jingyuan zhu, Guangtian Beijing Inst of Electromechanic Sys Eng Beijing China

This paper presents a brief summary of the three development stages of investigation on the transpiration cooling and its control for aircraft, missiles and electromagnetic gun, then the control problem of the distributed parameters system with a moving boundary is derived. It introduces the mathematical model of the transpiration cooling control, its control characteristics, and the present situation of the experimental and theoretical study on this problem. This paper also describes the main study results and the existing problems. The prospective application is also reported. The major references in every developing stage are listed systematically for further study.

关键词： Ablation Boundary layer flow Boundary layers Cooling Experiments Flow control Heat transfer Mathematical models Temperature control

An improved practical model for wear prediction of revolute clearance joints in crank slider mechanisms

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Science China(Technological Sciences) 2013年第12期56卷 2953-2963页

作者： LI Pei CHEN Wei zhu AiBin Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong University

A stationary clearance link algorithm(SCLA)for calculating the reaction-force of revolute clearance joints in crank slider mechanisms is proposed in this *** SCLA is more efficient than other algorithms of the same ***,based on the Winkler foundation model,an unsymmetrical Winkler foundation model and a double elastic layer Winkler model are *** integrating a dynamic model and the unsymmetrical Winkler foundation model with Archard wear model,an improved integrated wear prediction model is also generated.A series of experiments have been performed to compare with the predicted analysis data,and the results showed a good *** a real industry application,with the double elastic layer Winkler model,the integrated wear prediction model was successfully used to predict the wear depth of the joint bearing(bimetallic bearing)for the cantilever crane of a concrete pump truck of Sany Heavy Industry.

关键词： revolute clearance joint stationary clearance link algorithm unsymmetrical Winkler foundation model double elastic layer Winkler model

Cleaning the energy sources for water heating among Nanjing households： barriers and opportunities for solar and natural gas

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Frontiers of Environmental Science & Engineering 2014年第5期8卷 757-766页

作者： Lingyun zhu Beibei LIU Jun BI School of the Environment Nanjing University Nanjing 210046 China

Energy for water heating accounts for an increasing part in residential energy demand in China. An extensive survey was conducted to analyze the determinants of household energy choices for water heaters among residents in Nanjing, China. Two sets of variables were examined as potential influences： building features and household socio-economic characteristics. Results suggest that building features such as gas availability and building structures, and household characteristics such as household head＇s education degree and energy-conserving sense are crucial determinants in choosing natural gas as water heater energy. Installation permission for solar water heater, building stories, and residential location serve as determining factors in choosing solar water heaters. Based on these, barriers and opportunities are discussed for transitions toward cleaner water heating energies, and suggestions are given for local governments to promote cleaner energy replacement in China.

关键词： residential energy demand water heating,multinomial logit model

T lymphocytes in the intestinal mucosa: defense and tolerance

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Cellular & Molecular Immunology 2019年第3期16卷 216-224页

作者： Hongdi Ma Wanyin Tao Shu zhu Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Life SciencesUniversity of Science and Technology of China230027 HefeiChina School of Data Science University of Science and Technology of China230026 HefeiChina

Although lymphocytes are known to circulate throughout lymphoid tissues and blood,they also establish residency in nonlymphoid organs,most prominently in barrier tissues,such as the *** adaptation of T lymphocytes to intestinal environments requires constant discrimination between natural stimulation from commensal flora and food and pathogens that need to be *** variations that cause a defective defense or a break in tolerance along with environmental cues,such as infection or imbalances in the gut microbiota known as dysbiosis,can trigger several immune disorders via the activation of T lymphocytes in the *** of the immune mechanisms that distinguish between commensal flora and pathogenic organisms may reveal therapeutic targets for the prevention or modulation of inflammatory diseases and boost the efficacy of cancer *** this review,we discuss the development and adaptation of T lymphocytes in the intestine,how these cells protect the host against pathogenic infections while tolerating food antigens and commensal microbiota,and the potential implications of targeting these cells for disease management and therapeutics.

关键词： Intestinal T cells Pathogenic infection Gut microbiota T-cell therapy

Influence of the Physical Environment on the Migration and Distribution of Nibea albiflora in the Yellow Sea

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Journal of Ocean University of China 2017年第1期16卷 87-92页

作者： zhu Xianye WU Kejian WU Lunyu Physical Oceanography Laboratory Ocean University of China First Institute of Oceanography State Oceanic Administration

This study investigates the migration and distribution of the warm-temperate fish Nibea albiflora. Their spawning migration and wintering migratory routes within in the Yellow Sea are described in detail. Considering the main physical features and environment of the Yellow Sea, it appears to be have one wintering ground and three migratory routes from the wintering ground to the spawning grounds. The fish begin to migrate from the wintering ground to the spawning grounds in the northwest region of the Yellow Sea in late March. The Yellow Sea has three spawning grounds. The first is located near the Yalu River on the Liaodong Peninsula and the second one is located in Rushan Bay of Shandong Peninsula. The third spawning ground is located in Haizhou Bay in the southern region of the Yellow Sea. This study found that the temperature of the Yellow Sea influences the migration of N. albiflora, and that the migratory routes coincide with the thermal fronts in the sea. Nutrients for juvenile fish are taken from the coastal upwelling area. Chlorophyll is a good environmental indicator of phytoplankton biomass and thereby provides the status of biological resources. Different types of sediment in near-shore zones are also of practical significance for the growth of fish. The study of the effects of marine environments on the migration of various fishes is not only significant to the fishing industry, but can also provide a scientific basis for the understanding of the ecological implications of the relevant physical processes.

关键词： Nibea albiflora migration temperature chlorophyll sediments

Dynamical Artificial Bee Colony for Energy-Efficient Unrelated Parallel Machine Scheduling with Additional Resources and Maintenance

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Computers, Materials & Continua 2024年第10期81卷 843-866页

作者： Yizhuo zhu Shaosi He Deming Lei School of Science Hong Kong University of Science and TechnologyHong Kong999077China School of Automation Wuhan University of TechnologyWuhan430070China

Unrelated parallel machine scheduling problem(UPMSP)is a typical scheduling one and UPMSP with various reallife constraints such as additional resources has been widely studied;however,UPMSP with additional resources,maintenance,and energy-related objectives is seldom *** Artificial Bee Colony(ABC)algorithm has been successfully applied to various production scheduling problems and demonstrates potential search advantages in solving UPMSP with additional resources,among other *** this study,an energy-efficient UPMSP with additional resources and maintenance is considered.A dynamical artificial bee colony(DABC)algorithm is presented to minimize makespan and total energy consumption *** heuristics are applied to produce the initial *** bee swarm and onlooker bee swarm are *** resources are shifted from the dominated solutions to non-dominated solutions in each swarm when the given condition is *** employed bee phase is implemented by computing resource shifting and solution *** resource shifting and feedback are used to construct dynamical onlooker bee *** experiments are conducted on 300 instances from the literature and three comparative algorithms and ABC are compared after parameter settings of all algorithms are *** computational results demonstrate that the new strategies of DABC are effective and that DABC has promising advantages in solving the considered UPMSP.

关键词： Artificial bee colony parallel machine scheduling energy additional resource

Statistical Modeling of CMIP5 Projected Changes in Extreme Wet Spells over China in the Late 21st Century

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Journal of Meteorological Research 2017年第4期31卷 678-693页

作者： Lianhua zhu Yun LI Zhihong JIANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Nanjing 210044 China School of Mathematics and Statistics Nanjing University of Information Science & Technology Nanjing 210044 China Business Intelligence & Data Analytics Western Power WA 6000 Australia

The observed intensity, frequency, and duration（IFD） of summer wet spells, defined here as extreme events with one or more consecutive days in which daily precipitation exceeds a given threshold（the 95th percentile）, and their future changes in RCP4.5 and RCP8.5 in the late 21st century over China, are investigated by using the wet spell model（WSM） and by extending the point process approach to extreme value analysis. Wet spell intensity is modeled by a conditional generalized Pareto distribution, frequency by a Poisson distribution, and duration by a geometric distribution, respectively. The WSM is able to realistically model summer extreme rainfall spells during 1961–2005, as verified with observations at 553 stations throughout China. To minimize the impact of systematic biases over China in the global climate models（GCMs） of the Coupled Model Intercomparison Project Phase 5（CMIP5）, five best GCMs are selected based on their performance to reproduce observed wet spell IFD and average precipitation during the historical period. Furthermore, a quantile–quantile scaling correction procedure is proposed and applied to produce ensemble projections of wet spell IFD and corresponding probability distributions. The results show that in the late 21st century, most of China will experience more extreme rainfall and less low-intensity rainfall. The intensity and frequency of wet spells are projected to increase considerably, while the duration of wet spells will increase but to a much less extent. The IFD changes in RCP8.5 are in general much larger than those in RCP4.5.

关键词： wet spell model extreme value theory bias correction Coupled Model Intercomparison Project Phase 5

Research on fabric characteristics and borehole instability mechanisms of fractured igneous rocks

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Petroleum Science 2013年第2期10卷 212-218页

作者： Liu Xiangjun zhu Honglin Liang Lixi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University

There are favorable exploration prospects in igneous rock reservoirs. However, problems of borehole instability occur frequently during drilling igneous formations, which is a serious impediment to oil and gas exploration and production. The lack of systematic understanding of the inherent instability mechanisms is an important problem. A series of experiments were conducted on several igneous rock samples taken from the sloughing formations in the Tuha area in an attempt to reveal the inherent mechanisms of wellbore instability when drilling in fractured igneous rocks. Research methods involved slurry chemistry, analysis of micro-geological features （Micro-CT imaging, SEM）, and rock mechanics testing. The experimental results indicated that clay minerals were widely distributed in the intergranular space of the diagenetic minerals, crystal defects, and microcracks. Drilling fluid filtrate would invade the rock along the microcracks. Tile invasion amount gradually increased over time, which constantly intensified the hydration and swelling of clay minerals, leading to changes in the microscopic structure of igneous rocks. Primary and secondary microcracks can propagate and merge into single cracks and thus reducing rock cohesion and the binding force along cleavage planes. Based on this result the authors propose that a key towards solving wellbore instability in igneous formations is that specific micro-geological characteristics of the igneous rocks should be taken into consideration in the design of antisloughing drilling muds.

关键词： Igneous rocks microcracks clay minerals hydration instability

On Complete Hypersurfaces with Constant Mean Curvature and Finite L^p-norm Curvature in R^(n+1)

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Acta Mathematica Sinica,English Series 2005年第3期21卷 631-642页

作者： Yi Bing SHEN Xiao Hua zhu Department of Mathematics Zhejiang University Hangzhou 310028 P. R. China School of Mathematical Sciences Peking University Beijing 100871 P. R. China

By using curvature estimates, we prove that a complete non-compact hypersurface M with constant mean curvature and finite L^n-norm curvature in R^1＋1 must be minimal, so that M is a hyperplane if it is strongly stable. This is a generalization of the result on stable complete minimal hypersurfaces of R^n＋1. Moreover, complete strongly stable hypersurfaces with constant mean curvature and finite L^1-norm curvature in R^1＋1 are considered.

关键词： Constant mean curvature Strong stability L^p-norm curvature