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Performance Improvement of NCSs Under Complex Network via Concurrent Paths

Journal of Systems Science & Complexity 2019年第2期32卷 453-478页

作者： WANG zhan-yu LIU Guo-Ping School of Mechanical and Electrical Engineering Harbin Institute of Technology School of Engineering University of South Wales

Different from the single paths between controllers and plants of networked control systems(NCSs), the complex network provides widespread links and brings plenty of paths from the controller side to the plant side. Benefit from this advantage, a novel data transmission dispatching strategy is proposed. When the direct path can not satisfy the condition of system demand, neither stability nor performance, some specified paths compose a concurrent-path to transmit the control signal concurrently. Firstly, the networked control systems(NCSs) are expressed by the switched systems model with the constant network-induced delay, and the network communication is described as a packet-loss process. Secondly, taking system's exponential decay rate as its performance indicator, the relationship between control signal transmission paths and system performance is quantitatively given by considering packet losses as the compound poisson process and the alternating renewal process. Then, due to that different combination of paths induces the different statistical properties of packet losses, the approach to find an appropriate concurrent-path is proposed concerning two mutually constrained factors, the system performance demand and the utilization of network resources. After the theoretical analysis, a distributed communication platform based on peer-to-peer(P2P) network technology is designed and implemented to realize the concurrent-path transmission on internet. Finally, the practical experiment on the platform demonstrates the validity and effectiveness of proposed approach.

关键词： Dispatching strategy networked control system. P2P switched system transmission platform for networked control systems

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Effect of swirling flow on platelet concentration distribution in small-caliber artificial grafts and end-to-end anastomoses

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Acta Mechanica Sinica 2011年第5期27卷 833-839页

作者： Fan zhan yu-Bo Fan Xiao-Yan Deng Key Laboratory for Biomechanics and Mechanobiologyof Ministry of Education School of Biological Science and Medical EngineeringBeihang University 100191 Beijing China

Platelet concentration near the blood vessel wall is one of the major factors in the adhesion of platelets to the *** our previous studies,it was found that swirling flows could suppress platelet adhesion in small-caliber artificial grafts and end-to-end *** order to better understand the beneficial effect of the swirling flow,we numerically analyzed the near-wall concentration distribution of platelets in a straight tube and a sudden tubular expansion tube under both swirling flow and normal flow *** numerical models were created based on our previous experimental *** simulation results revealed that when compared with the normal flow,the swirling flow could significantly reduce the near-wall concentration of platelets in both the straight tube and the expansion *** present numerical study therefore indicates that the reduction in platelet adhesion under swirling flow conditions in small-caliber arterial grafts,or in end-to-end anastomoses as observed in our previous experimental study,was possibly through a mechanism of platelet transport,in which the swirling flow reduced the near-wall concentration of platelets.

关键词： Platelet near-wall concentration · Swirling flow · Small-caliber arterial grafts · End-to-end anastomosis

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Pollution characteristics of 15 gas- and particle-phase phthalates in indoor and outdoor air in Hangzhou

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Journal of Environmental Sciences 2019年第12期31卷 107-119页

作者： Xingzi Ouyang Meng Xia Xueyou Shen yu zhan College of Environmental&Resource Sciences Zhejiang UniversityHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control HangzhouZhejiang 310058China Department of Environmental Science and Engineering Sichuan UniversityChengduSichuan 610065China

Phthalate esters(PAEs),typical pollutants widely used as plasticizers,are ubiquitous in various indoor and outdoor *** exist in both gas and particle phases,posing risks to human *** the present study,we chose four typical kinds of indoor and outdoor environments with the longest average human residence times to assess the human exposure in Hangzhou,including newly decorated residences,ordinary residences,offices and outdoor *** order to analyze the pollution levels and characteristics of 15 gasand particle-phase PAEs in indoor and outdoor environments,air and particulate samples were collected *** total PAEs concentrations in the four types of environments were 25,396,25,466.8,15,388.8 and 3616.2 ng/m^3,*** and DEP were the most abundant,and DMPP was at the lowest *** variations in the distributions of indoor/outdoor,gas/particle-phase and different molecular weights of PAEs were observed,showing that indoor environments were the main sources of PAEs *** most PAEs tended to exsit in indoor sites and gas-phase,the high-molecular-weight chemicals tended to exist in the particle-phase and were mainly found in *** were more likely adsorbed by small particles,especially for the indoor *** existed a good correlation between the particle matter concentrations and the PAEs *** addition,neither temperature nor humidity had obvious effects on the distributions of the PAEs concentrations.

关键词： Phthalate esters Indoor and outdoor air Gas and particle phase Distribution characteristics Particles

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Preparation of Polyimide/BaTiO_3/Ag Nanocomposite Films via in situ Technique and Study of Their Dielectric Behavior

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Chinese Journal of Polymer Science 2014年第4期32卷 424-431页

作者： Jia-yu zhan Guo-feng Tian zhan-peng Wu Sheng-li Qi 武德珍 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Building Materials Academy of Science Research/State Key Laboratory of Solid Waste Reuse for Building Materials

Triphase polyimide nanocomposite films were fabricated using barium titanate （BaTiO3） with high dielectric constant and silver （Ag） with high conductivity as fillers. In situ method was utilized to obtain the homogeneous dispersion of nanoparticles. The in situ polymerization of polyimide precursor-poly（amic acid） was performed in the presence of BaTiO3 particles. Silver compound 1,1,1-trifluoro-2,4-pentadionato silver（I） was added into the BaTiO3 containing poly（amic acid） solution to achieve silver nanoparticles via in situ self metallization technique. The thermally induced reduction converted silver （I） to metallic silver with concomitant imidization of poly（amic acid） to polyimide. Both BaTiO3 and silver nanoparticles were uniformly dispersed in the polyimide substrate. The dependence of dielectric behavior on the BaTiO3 and Ag contents was studied. The incorporation of small amount of silver nanoparticles greatly increased dielectric constant of composite films.

关键词： Polyimide Silver Barium titanate Nanocomposites Dielectrics.

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Preparation of Low Cost Activated Carbon from Deactivated Resin Catalyst for Methyl Tert-Butyl Ether Synthesis and Its Application in Dimethyl Sulfide Adsorption with Transition Metal Impregnation

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China Petroleum Processing & Petrochemical Technology 2017年第2期19卷 55-64页

作者： yu zhan Shi Li Meng Xuan The State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237

In this paper, a low-cost activated carbon(AC) was prepared from deactivated resin catalyst(DRC) for methyl tert-butyl ether(MTBE) synthesis through carbonization and subsequent steam activation treatment. The activated carbon was characterized in detail. After loading various transition metals, including Cu^(2+), Ag+, Co^(2+), Ni^(2+), Zn^(2+), and Fe^(3+) via the ultrasonic-assisted impregnation method, a series of metal-loaded adsorbents(xM-AC) were obtained and their dimethyl sulfide(DMS) adsorption performance was investigated in a batch system. Among these adsorbents, 15Cu-AC presented a superior DMS adsorption capacity equating to 58.986 mg/g due to the formation of S-M(σ) bonds between Cu^(2+) and sulfur atoms of DMS as confirmed by the Raman spectra and kinetic study.

关键词： activated carbon deactivated resin catalyst dimethyl sulfide transition metal

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DNA methylation detection methods used in colorectal cancer

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World Journal of Clinical Cases 2019年第19期7卷 2916-2929页

作者： yu-Xia zhan Guang-Hua Luo Comprehensive Laboratory Changzhou Key Lab of Individualized Diagnosis and Treatment Associated with High Technology Research the Third Affiliated Hospital of Soochow University

Colorectal cancer(CRC)remains a major contributor to the number of cancerrelated deaths that occur annually *** the development of molecular biology methods,an increasing number of molecular biomarkers have been identified and *** is believed to result from an accumulation of epigenetic changes,and detecting aberrant DNA methylation patterns is useful for both the early diagnosis and prognosis of *** studies are focusing on the development of DNA methylation detection methods or DNA methylation ***,this review will discuss the commonly used techniques and technologies to evaluate DNA methylation,their merits and deficiencies as well as the prospects for new methods.

关键词： Colorectal cancer Cancer screening Marker DNA methylation detection

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Effect of flow control mold on flow field during high-speed continuous casting

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Advances in Manufacturing 2017年第3期5卷 271-278页

作者： zhan yu Zheng-Qiang zhang Zhong-Ming Ren Nanjing Iron and Steel Co. Ltd. Nanjing 210035 JiangsuPeople's Republic of China Shanghai Key Laboratory of Modem Metallurgy andMaterials Processing Shanghai University Shanghai 200072 People's Republic of China

An experimental mold was built to study the flow in a flow control mold under high speed continuous casting. The effect of the magnetic field on the flow was investigated using mercury. The results show that the magnetic field can not only dampen the flow of liquid metal but also change its direction, and then redistribute the flow in the mold. When maintaining a constant distance between magnets, the fluctuation of the free surface is dampened because of the increasing magnetic flux density. The flow at the free surface is improved, and the penetration depth of the downward stream is reduced. The decrease in the dis- tance between magnets promotes the brake effect and the flow is dampened in the upper eddy.

关键词： High-speed continuous casting Flow control(FC) mold Flow of liquid metal ·Electromagnetic brake

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Antioxidant Activities of Aqueous Extract from Cultivated Fruit-bodies of Cordyceps militaris （L.） Link In Vitro

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Journal of Integrative Plant Biology 2006年第11期48卷 1365-1370页

作者： yu zhan Cai-Hong Dong Yi-Jian Yao Key Laboratory of Systematic Mycology and Lichenology Institute of Microbiology the Chinese Academy of Sciences Beijing 100080 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Biological antloxldants extracted from plants and fungi have potential abilities to scavenge free radicals and Inhibit lipid peroxldatlon, playing Important roles in preventing diseases, for example, cancer, and aging Induced by reactive oxygen species, which may cause oxidative damage to DNA, proteins and other macromolecules. The antloxldant potency of cultivated fruit-bodies of Cordyceps militarls （L.） Link was investigated In this study. Five established In vitro systems were employed, including the 1,1-dlphenyl-2- plcryldrazyl （DPPH） free radical scavenging, hydroxyl radical eliminating, iron chelating, Inhibition of Ilnolelc acid lipid peroxldatlon and reducing power. The aqueous extract from cultivated fruit-bodies was subjected to the test of amino acid, polysaccharlde and mannitol. Ascorblc acid （Vc）, butylated hydroxytoluene （BHT） and ethylenedlamlnetetraacetlc acid （EDTA） were used as positive controls for comparisons. Among the assays, the aqueous extract of C. mllltarls frult-bodles shows a significant scavenging effect on DPPH, eliminating the capability on hydroxyl radicals and the chelating effect on ferrous Iron. The extract also shows positive results of Inhibiting Ilnoleic acid lipid peroxldatlon and reducing power.

关键词： antioxidation aqueous extract Cordyceps militaris free radicals in vitro.

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Occupational exposure assessment of phthalate esters in indoor and outdoor microenvironments

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Journal of Environmental Sciences 2018年第10期30卷 75-88页

作者： Meng Xia Xingzi Ouyang Xueqing Wang Xueyou Shen yu zhan College of Environmental & Resource Sciences Zhejiang UniversityHangzhou Zhejiang 310058 China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Hangzhou Zhejiang 310058 China

Phthalate esters（PAEs） are widely used as plasticizers in consumer products. PAEs are a group of environmental hormone which disrupts human and animals＇ endocrine systems. Different occupational groups are exposed to various levels of PAEs. In the present study, four typical occupational groups were chosen, including doctors, college teachers, college students, and drivers who worked in public traffic system. In order to understand the exposure levels to PAEs via inhalation, air samples were collected from multiple microenvironments including indoor and outdoor in Hangzhou to measure the gas and particle concentrations of six PAEs, together with time spent in different microenvironments of these four groups. A comprehensive PAEs exposure model was built to estimate the daily PAEs exposure through inhalation, oral and dermal pathways. The Monte Carlo simulation results show that doctors were exposed to the highest level of PAEs, and consequently had the highest health risk among these four occupational groups. In contrast, college students had the lowest health risk. By setting the exposure level of staying in residences as the baseline, doctors and drivers were two occupations exposed to high PAEs health risk. Di-（2-ethylhexyl） phthalate（DEHP） was the largest contributor among the six phthalates, posing moderate health risk（10-5–10-6） to every occupation. For traffic microenvironments alone, the total exposure levels for different transportation modes were in the descending order of busses, cars, cabs, tubes, motor bikes, and walking.

关键词： Phthalate esters Microenvironment Occupation Exposure assessment Uncertainty analysis

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Effect of heat treatment on cyclic deformation properties of Fe-26Mn-10AI-C steel

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Journal of Iron and Steel Research International 2019年第2期26卷 200-210页

作者： He Li Jian-ping Zhao zhan-yu Wang Li Ding School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816JiangsuChina Jiangsu Key Lab of Design and Manufacture of Extreme Pressure Equipnient Nanjing 211816JiangsuChina

Fully reversed tensile-compression low-cycle fatigue tests were performed at room temperature under strain amplitude of 0.4%.The monotonic tensile results show that Fe-26Mn-10A1-C steels are fully austenite and(he optimal combination of ultimate tensile strength and total elongation was present at 950°C with 65 GPa%.The fatigue results show that the specimen at 1050°C has the maximum fatigue life of 162,000 cycles,which is much longer than twinning-induced plasticity(TWIP)steels of the same strain *** hot-forging specimen shows high similarity with TWIP steels with rapid initial cyclic hardening followed by cyclic softening and cyclic *** solution heat treatment,it is noteworthy that,after rapid initial cyclic softening,another rapid cyclic hardening and a following decrease with fluctuation were observed at 1000°*** is reas on able to believe that it is caused by K-carbides precipitated during cyclic *** interesting phenomenon is cyclic stress subsidence observed at 1050°C during its saturation stage at the last quarter of the fatigue life,and the span is about 12.5%of whole fatigue life.

关键词： Fe-Mn-AI-C steel Low-cycle fatigue Cyclic hardening Cyclic softening Cyclic stress subsidence

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