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    题名 作者 年代 出处 被引量
12005年全国治超工作要点显示文摘Issued by Ministry of Communications of the People′s Republic of China,T he Ministry of Public Security of the People′s Republic of China,National Development and Reform Comm ission,the Ministry of Propaganda of the CPC Central Committee,General Administration of Qu ality Supervision Inspection and Quarantine of the PRC,State Administration of Work Safety,State Administration for Industry & Commerce,China Legislative 2005交通标准化2005,,5:34
2Review on hidden trouble detection and health diagnosis of hydraulic concrete structures显示文摘A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures.WU ZhongRu1,2?, LI Ji1, GU ChongShi1,2 & SU HuaiZhi1,2 1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Nanjing 210098, China 2007Science China(Technological Sciences)2007,50,z1:27
3Multivariate analysis in dam monitoring data with PCA显示文摘Given the limitation of traditional univariate analysis method in processing the multicollinearity of dam monitoring data,this paper reconstructs the multivariate response variables by introducing principal component analysis(PCA) method,explores the ways of determining principal components(PCs),and extracts a few PCs that have major influence on data variance.For steady observation series,a control field for the whole observation values has been established based upon PCA;for unsteady observation series that have significant tendency,a control field for the future observation values has been constructed according to PC statistical predication model.These methods have already been applied to an actual project and the results showed that data interpretation method with PCA can not only realize data reduction,lower data redundancy,and reduce noise and false alarm rate,but also be effective to data analysis,having a broad application prospect.YU Hong1,2,WU ZhongRu1,2,BAO TengFei1,2 & ZHANG Lan1,2 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,Nanjing 210098,China 2010Science China(Technological Sciences)2010,53,4:16
4Detection of subcritical crack propagation for concrete dams显示文摘Subcritical propagation of cracks is a warning sign of fracture.If such propagation is detected at an early stage,timely maintenance measures can be taken to prevent the failure of structures.To detect the subcritical propagation of a crack,the crack needs to be monitored continuously in a long term, which is not realistic under certain conditions.However,cracks in concrete dams can be monitored continuously by dam monitoring to offer possible detection for subcritical propagation.In this paper, with measured crack openings from dam monitoring,a state equation for characterizing crack development is established based on the grey system theory.The relation between the stability of the equation and the subcritical crack propagation is investigated,then a criterion is proposed for detecting subcritical propagation.An example demonstrates the validity of the criterion and its potential for practical application.BAO TengFei1 ,2&YU Hong 1,2 1College of Water Conservancy&Hydropower Engineering,Hohai University,Nanjing 210098,China 2National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Nanjing 210098,China 2009Science China(Technological Sciences)2009,52,12:14
5Optimization model and algorithm for mixed traffic of urban road network with flow interference显示文摘In this paper,the problem of interferences between motors and non-motors in urban road mixed traffic network is considered and the corresponding link impedance function is presented based on travel demand.On the base of this,the main factors that influence travelers' traffic choices are all considered and a combined model including flow-split and assignment problem is proposed.Then a bilevel model with its algorithm for system optimization of urban road mixed traffic network is proposed.Finally the application of the model and its algorithm is illus-trated with a numerical example.SI BingFeng,LONG JianCeng & GAO ZiYou State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University,Beijing 100044,China 2008Science China(Technological Sciences)2008,51,12:13
6A fiber optic sensor for detecting and monitoring cracks in concrete structures显示文摘The formation and propagation of cracks reflect the aging and pathologic changes of concrete structures and may cause problems such as seepage and long-term durability. Crack detection and monitoring is therefore an effective way to evaluate structural health conditions. An important challenge in such a task is that the locations and orientations of cracks in concrete structures are difficult to predict due to material inhomogeneity and complexity. The number of the required conventional electric and electromagnetic sensors to cover all possible cracks may be too large to be practical for a monitoring scheme. In this paper, a fiber optic sensor with distributed crack sensing capability based on optical time domain reflectometry is proposed and its sensing principle is introduced. Experiments are conducted to obtain the optical power loss versus crack opening at different fiber inclination angles, and then a model is developed to quantify it. Finally, an experiment is performed to demonstrate the practical application of the sensor. The test results show that detecting and monitoring cracks with the sensor do not require a-priori knowledge of crack locations and orientations.BAO TengFei1,2*, WANG JiaLin1,2 & YAO Yuan1,2 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210024, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing 210024, China 2010Science China(Technological Sciences)2010,53,11:11
7FOXP3 expression and clinical characteristics of hepatocellular carcinoma显示文摘AIM: To study the biological and clinical characteristics of transcription factor forkhead box protein 3 (FOXP3) in hepatocellular carcinoma (HCC). METHODS: We analyzed the expression and localization of FOXP3 in HCC tissues and cell lines to evaluate its biological features. The relationship between FOXP3 staining and clinical risk factors of HCC was assessedto identify the clinical characteristics of FOXP3 in HCC. RESULTS: The mRNA and protein expression of FOXP3 were found in some hepatoma cell lines. Immunohistochemical (IHC) analysis of HCC sections revealed that 48% of HCC displayed FOXP3 staining, but we did not find any FOXP3 staining in normal liver tissues and para-tumor tissues. IHC and Confocal analysis showed that the expressions of FOXP3 were mainly present in the nucleus and cytoplasm of tumor cells in tissues or cell lines. In HCC, the distribution of FOXP3 was similar to that of the cirrhosis, but not to the hepatitis B virus. Those findings implicate that FOXP3 staining seems to be associated with the high risk of HCC. CONCLUSION: The clinical characteristics of FOXP3 in HCC warrants further studies to explore its functions and roles in the cirrhosis and development of HCC.Wei-Hua Wang, Jun-Zhi Wang, National Center for Safety Evaluation of Drugs, National Institute for the Control of Pharmaceutical and Biological Products, Beijing 100050, China Wei-Hua Wang, Chang-Li Jiang, Cun Zhang, Bo Yan, Wei Zhang, Wei Han, Ying-Qi Zhang, Biotechnology Center, School of Pharmacy, the Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China Wei-Hua Wang, Chang-Li Jiang, Cun Zhang, Bo Yan, Wei Zhang, Wei Han, Ying-Qi Zhang, State Key Laboratory of Cancer Biology, Xi’an 710032, Shaanxi Province, China Wei Yan, Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China Yu-Hai Zhang, Department of Health Statistics, The Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China Jiang-Tao Yang, Department of Pathology, Xi’an Gaoxin Hospital, Xi’an 710032, Shaanxi Province, China 2010World Journal of Gastroenterology2010,16,43:10
8Analysis of crack propagation in concrete structures with structural information entropy显示文摘The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.BAO TengFei1’2, PENG Yan1’2, CONG PeiJiang1’2 & WANG JiaLin1’2 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210024, China 2 National Engineering Research Center ofWater Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing 210024, China 2010Science China(Technological Sciences)2010,53,7:9
9Study on fire-retardant nanocrystalline Mg-Al layered double hydroxides synthesized by microwavecrystallization method显示文摘Nanocrystalline Mg-Al layered double hydroxides with the particle size being 10—40 nm were firstly prepared by the technology of the microwave-crystallization and the vari- able-speed addition of the alkali. The obtained samples were characterized by TEM and XRD. The roles of the microwave and addition rate of the alkali were also discussed in the present work. The thermal decomposition activation energy of the nano-LDHs was calculated according to their TG, DTG and DSC curves by the Ozawa method. The results showed that the thermal decom- position of the nano-LDHs had four steps. Thereby the decomposition model of the nano-LDHs was supposed according to the analysis of their thermal decomposition. After PS, ABS, HDPE and PVC were filled with the nano-LDHs, their LOI values could be increased up to 28, 27, 26 and 33, respectively. When the fire-retardant coating contained 1.9% of the nano-LDHs that was 0.27 times the dosage of the conventional TiO2, its fire endurance time reached 32.75min that was 7.05 min longer than that of the best coating containing TiO2 according to the model big-panel combustion test method.ZHANG Zejiang1, XU Chenghua1, QIU Fali1, MEI Xiujuan2, LAN Bin2 & ZHANG Shuosheng2 1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China 2. Sichuan Fire Research Institute of Public Safety Ministry, Chengdu 611830, China 2004Science China Chemistry2004,47,6:9
10Back analysis of mechanical parameters of roller compacted concrete dam显示文摘In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam displacements.During the process of back analysis,the initial samples of parameters were designed with uniform design method.Then,a transversely isotropic model of RCCD was established by MSC.Marc software.Through this model,training samples of LSSVM model could be obtained.And then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was established.Finally,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using PLS.By inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be obtained.The example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.GU ChongShi 1,2,3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2College of Water Conservancy Hydropower,Hohai University,Nanjing 210098,China 3National Engineering Research Center of Water Resources Engineering Safety,Efficient Utilization and Nanjing 210098,China 4 Nanjing Hydraulic Research Institute,Nanjing 210029,China 2010Science China(Technological Sciences)2010,53,3:8
11An integrated turbocharger design approach to improve engine performance显示文摘Turbocharging technology is today considered as a promising way for internal combustion engine energy saving and CO2 reduction.Turbocharger design is a major challenge for turbocharged engine performance improvement.The turbocharger designer must draw upon the information of engine operation conditions,and an appropriate link between the engine requirements and design features must be carefully developed to generate the most suitable design recommendation.The objective of this research is to develop a turbocharger design approach for better turbocharger matching to an internal combustion engine.The development of the approach is based on the concept of turbocharger design and interaction links between engine cycle requirements and design parameter values.A turbocharger through flow model is then used to generate the design alternatives.This integrated method has been applied with success to a gasoline engine turbocharger assembly.ZHANG YangJun1,CHEN Tao1,ZHUGE WeiLin1,ZHANG ShuYong2 & XU JianZhong3 1 State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China 2 National Key Laboratory of Diesel Engine Turbocharging Technology,P.O.B.22,Datong 037036,China 3 Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China 2010Science China(Technological Sciences)2010,53,1:8
12Study on Migration of Melamine from Food Packaging Materials on Markets显示文摘Objectives To study the migration of melamine into foods from plastic food packaging materials and dairy product containers commonly used in China. Methods 37 samples were collected from the market. The EU migration testing conditions were adopted with distilled water, 3% acetic acid, n-hexane and 15% ethanol being chosen as the simulating solutions. The HPLC method was used to detect melamine. Results No melamine was detected in 15 dairy product containers. Among the 22 plastic samples, 16 of polypropylene, and polycarbonate types had no detectable amount melamine while a low level of melamine was found in 3 of the 6 melamine resin containers. Conclusion Migration of melamine from food packaging materials in China market is in line with the requirements of EU.JIE LU*, JING XIAO*, DA-JIN YANG, ZHU-TIAN WANG1, DING-GUO JIANG, CONG-RONG FANG, AND JIE YANG Institute of Nutrition and Food Safety, Chinese Centor for Disease Control and Prevention, Beijing 100021, China 2009Biomedical and Environmental Sciences2009,22,2:7
13Electromagnetic radiation early warning criterion of rock burst based on statistical theory显示文摘Rock bursts are serious natural disasters encountered worldwide in coal mining and rock engineering.In order to forecast rock bursts more effectively,a new rock burst forecasting index E,consisting of intensity and the number of pulses,is proposed,on the basis of abnormal characteristic symptoms of electromagnetic radiation(EMR) generated before rock bursts,combined with statistical theory.The index is distributed as a χ2 distribution with 2 degrees of freedom,i.e.,E~χ 2(2).Via this index,a quantitative comprehensive forecasting criterion of EMR was initially established.E values were calculated when the occurrence probability of the occurrence of a rock burst was 50%,70% and 90%.Appropriate measures should be taken when using these values on the scene.Using EMR data collected in the Nanshan Mine of the Hegang mining area,we verified that the analytical result were consistent with actual situations.This index is of theoretical importance and as a reference for forecasting rock bursts in coal mines.SONG Dazhao,WANG Enyuan,WANG Chao,XU Fule School of Safety Engineering,China University of Mining & Technology,Xuzhou 221008,China 2010Mining Science and Technology2010,20,5:7
14Analysis on ignition and extinction of n-heptane in homogeneous systems显示文摘To calculate ignition delay times, the governing equations about species and temperature, which are in a closed volume based on the theory of thermal explosion and in a continuously stirred flow reactor, are deducted. The method referred to steady state assumptions is based on the observation that due to very fast chemical processes in combustion problems many chemical species and reactions are in a quasi-steady state or partial equilibrium. When a species is assumed to be in the steady state, the corresponding differential equation can be replaced by an algebraic relation, which reduces the computational costs. The steady state solution of the reactor equations describes the three ignition temperature regimes and get “S-shaped curve”. The reduced simplified 4-step mechanism for n-heptane from 1011 elementary reactions leads with the steady state assumptions to linear differential equations, which is solved. The simulation results of the 4-step reduced mechanism for n-heptane are fitted well with the experiment data. At last, two important parameters are discussed thoroughly and the temperature perturbation is given. It reduces the computational efforts considerably without losing too much accuracy and further supplies numerical methods for turbulent combustion in the diesel engine.LIU Yongfeng1 & PEI Pucheng2 1. Mechanical and Electrical Engineering Department, Beijing Institute of Civil Engineering and Architec-ture, Beijing 100044, China 2. State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China 2005Science China(Technological Sciences)2005,48,5:7
15Kuroshio warm filament and the source of the warm water of the Tsushima Current显示文摘Characteristics and evolution of the Kuroshio frontal eddies and warm filaments are analyzed according to two series of satellite images (March 5 to 7, 1986 and April 14 to 16, 1988). The results show that the frontal eddies in the East China Sea are generated at the shelf break and move along the continental slope at a speed of 15 cm/s with the Kuroshio. The frontal eddies occur about every 10 d and evolve to be warm filaments a few hundred km in length and 30-40 km in width in the area west of the Yaku-shima. Meanwhile, the existence of the warm filament was also found in the area by analysing the hydrographic data in the area west of Kyushu during May 24-June 5, 1988.The Kuroshio warm filaments move westward opposite to the Kuroshio and then turn northward at the shelf break and become the main source of the warm water of the Tsushima Warm Current. A simple dynamic explanation for the process is presented in this paper.Guo Binghuo, Xiu Shumeng, Haruo Ishii and Yasuaki Nakamura First Institute of Oceanography, State Oceanic Administration, Oingdao, 266003, ChinaHydrographic Department, Maritime Safety Agency, Tokyo, JapanSeikai Fisheries Research Institute, Fisheries Agency Nagasaki, Japan 1991Acta Oceanologica Sinica1991,10,3:6
16关于在全国开展车辆超限超载治理工作的实施方案显示文摘按照中共中央<关于完善社会主义市场经济体制若干问题的决定>和党的十六届三中全会提出的树立全面、协调、可持续发展观的要求,根据<中华人民共和国公路法>和<中华人民共和国道路交通安全法>的规定,为维护社会主义市场经济秩序,解决货运机动车辆超限超载运输问题,减少道路交通安全事故的发生,保护人民群众生命和国家、集体、个人财产安全,经国务院同意,决定在全国开展货运机动车辆(以下简称车辆)超限超载治理工作.现提出如下实施方案.(Issued by the Ministry of Communications, the Ministry of Police, Develop and Reform Committee, Quality Survey General Bureau, Safety Survey Administration Bureau, Industrial and Commercial Bureau,Legal System Office, on April 30, 2004.) 2004交通标准化2004,,9:6
17Design objectives and collapse prevention for building structures in mega-earthquake显示文摘A 'mega-earthquake' is one with an intensity larger than the most severe earthquake intensity category currently considered in design codes. For a 'mega-earthquake,' the design objective of a given structure is to 'preserve living spaces for people in the buildings.' In this paper,factors that may influence the collapse resistance of RC frames in a mega-earthquake are analyzed based on seismic damage observed in the 2008 Wenchuan earthquake. Methodologies to improve structural collapse resistance focus on three aspects:global strength margin,global redundancy and global integration of the structural system. Fundamental principles and design concepts for collapse prevention under a mega-earthquake are proposed,and issues that need further research are identified.Ye Lieping1,2,Lu Xinzheng1,2 and Li Yi1,2 1.Department of Civil Engineering,Tsinghua University,Beijing 100084,China 2.Key Laboratory of Civil Engineering Safety and Durability,Ministry of Education of China,Beijing 100084,China 2010Earthquake Engineering and Engineering Vibration2010,9,2:6
18A new method of estimating the equivalent elastic modulus of RCCD显示文摘Based on the composite material mechanic theory, the analysis method for the equivalent elastic moduli which are parallel and vertical to the construction interface of RCCD is studied in this paper. The differences between the equivalent elastic moduli which are vertical to the construction interface of RCCD gotten from different methods are discussed in detail. The variation range of the equivalent elastic modulus which is vertical to the construction interface of RCCD is studied based on the principle of minimum complementary energy and the principle of minimum potential energy. The effect of the related influential factors on the equivalent elastic modulus is analyzed. The estimation formula of the equivalent modulus which is vertical to the construction interface of RCCD is proposed. The feasibility of the approach proposed in this paper is analyzed through an example.GU ChongShi1,2?, WU Yuan1, SU HuaiZhi1,2 & TANG LiHui1 1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Nanjing 210098, China 2007Science China(Technological Sciences)2007,50,z1:6
19Urban expressway traffic state forecasting based on multimode maximum entropy model显示文摘The accurate and timely traffic state prediction has become increasingly important for the traffic participants,especially for the traffic managements. In this paper,the traffic state is described by Micro-LOS,and a direct prediction method is introduced. The development of the proposed method is based on Maximum Entropy (ME) models trained for multiple modes. In the Multimode Maximum Entropy (MME) framework,the different features like temporal and spatial features of traffic systems,regional traffic state are integrated simultaneously,and the different state behaviors based on 14 traffic modes defined by average speed according to the date-time division are also dealt with. The experiments based on the real data in Beijing expressway prove that the MME models outperforms the already existing model in both effectiveness and robustness.SUN XiaoLiang1,2, JIA LiMin1, DONG HongHui1, QIN Yong1 & GUO Min3 1State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University, Beijing 100044, China 2School of Traffic and Transportation, Beijing Jiaotong University, Beijing 100044, China 3Beijing Traffic Management Bureau, Beijing 100044, China 2010Science China(Technological Sciences)2010,53,10:6
20Research and development on transonic compressor of high pressure ratio turbocharger for vehicle internal combustion engines显示文摘The pressure ratio required for a turbocharger centrifugal compressor increases with internal combustion engine power density. High pressure ratio causes a transonic flow field at the impeller inducer. Transonic flow narrows the stable flow range and de-teriorates stage efficiency. In this work, an advanced high pressure ratio transonic compressor was designed. The experimental results show that the maximum pressure ratio of this turbocharger is about 4.2, the maximum efficiency is above 80% and the stable flow range at the designed rotating speed is up to 34%. A turbocharger with this transonic compressor has been applied to some vehicle research actually, and improved power density by 40%.ZHENG XinQian, ZHANG YangJun & YANG MingYang State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China 2010Science China(Technological Sciences)2010,53,7:6
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