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Numerical calculation and influencing factors of the volume fraction of interfacial transition zone in concrete

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Science China(Technological Sciences) 2012年第6期55卷 1515-1522页

作者： sun GuoWen sun wei ZHANG YunSheng LIU ZhiYong Jiangsu Key Laboratory of Construction Materials Southeast UniversityNanjing 211189China

The determination of volume fraction of interracial transition zone （ITZ） is very important for investigating the quantitative relationship between the microstructure and macroscopical property of concrete. In this paper, based on Lu and Torquato＇s most nearest surface distribution function, a calculating process of volume fraction of ITZ is given in detail according to the actual sieve curve in concrete. Then, quantitative formulas are put forward to measure the influencing factors on the ｜TZ vol- ume fraction. In order to validate the given model, the volume fractions of ITZ obtained by numerical calculation are compared with those by computer simulation. The results show that the two are in good agreement. The order of the factors influencing the ITZ volume fraction is the ITZ thickness, the volume fraction of aggregate and the maximum aggregate diameter for Fuller gradation in turn. The 1TZ volume fraction obtained from the equal volume fraction （EVF） gradation is always larger than that from the Fuller gradation for a given volume fraction of aggregate.

关键词： concrete interfacial transition zone (ITZ) volume fraction Fuller distribution equal volume fraction distribution(EVF) sieve curve

Novel method of ordinal bearing estimation for more sources based on oblique projector

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Journal of Systems Engineering and Electronics 2009年第3期20卷 445-449页

作者： sun wei Bai Jianlin Wang Kai Missile Inst. Air Force Engineering Univ. Sanyuan 713800 P. R. China Aviation Equipment Academy Beijing 100085 P. R. China

A novel direction of arrival （DOA） estimation method is proposed when uncorrelated, correlated, and coherent sources coexist under color noise field. The uncorrelated and correlated sources are firstly estimated using the conventional spatial spectrum estimation method, then the noise and uncorrelated sources in Toeplitz structure are eliminated using differencing, finally by exploiting the property of oblique projection, the contributions of correlated sources are then eliminated from the covariance matrix and only the coherent sources remain. So the coherent sources can be estimated by the technique of modified spatial smoothing. The number of sources resolved by this approach can exceed the number of array elements without repeatedly estimating correlated sources. Simulation results demonstrate the effectiveness and efficiency of our proposed method.

关键词： spatial differencing oblique projector Toeplitz property direction of arrival estimation

Numerical study of size effect in concrete penetration with LDPM

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Defence Technology（防务技术） 2018年第5期14卷 560-569页

作者： Jun Feng wei-wei sun Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and Technology Department of Civil Engineering Nanjing University of Science and Technology

Projectile size effect is of great importance since the scaling researches are extensively applied to concrete penetration investigations. This paper numerically deals with the projectile size effect on penetration resistance via the recently developed Lattice Discrete Particles Model(LDPM) which is featured with mesoscale constitutive laws governing the interaction between adjacent particles to account for cohesive fracture, strain hardening in compression and compaction due to pore collapse. Simulations of two different penetration tests are carried to shed some light on the size effect issue. The penetration numerical model is validated by matching the projectile deceleration curve of and predicting the depth of penetration(DOP). By constant velocity penetration simulations, the target resistance is found to be dependent on the projectile size. By best fitting numerical results of constant velocity penetration, a size effect law for target resistance is proposed and validated against literature data. Moreover, the size effect is numerically obtained in the projectile with longer extended nose part meanwhile the shorter extended nose is found to improve the DOP since the projectile nose is sharpened.

关键词： Penetration of concrete Size effect Lattice discrete particle model Target resistance Abnormal nose projectile

Protective effect of resveratrol on rat cardiomyocyte H9C2 cells injured by hypoxia/reoxygenation by regulating mitochondrial autophagy via PTEN-induced putative kinase protein 1/Parkinson disease protein 2 signaling pathway

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Journal of Traditional Chinese Medicine 2022年第2期42卷 176-186页

作者： ZHAO Lixia sun wei BAI Decheng Institute of Integrated Traditional Chinese and Western Medicine School of Basic Medical SciencesLanzhou UniversityLanzhou 730000China School of Nursing Gansu University of Chinese MedicineLanzhou 730000China Key Laboratory of Dunhuang Medicine Ministry of EducationGansu University of Chinese MedicineLanzhou 730000China Cardiac Surgery the First Hospital of Lanzhou UniversityLanzhouGansu 730000China

OBJECTIVE:To investigate the protective effect of resveratrol on cardiomyocytes after hypoxia/reoxygenation intervention based on PTEN-induced putative kinase protein 1/Parkinson disease protein 2(PINK1/PARKIN)signaling ***:3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to detect the effect of resveratrol on the viability of H9C2 cells;the hypoxia/reoxygenation(H/R)model was established in tri-gas incubator;2’,7’-Dichlorofluorescin diacetate staining was used to measure the content of reactive oxygen species(ROS);the changes of mitochondrial membrane potential was determined by 5,5’,6,6’-Tetrachloro-1,1’,3,3’-tetraethyl-imidacarbocyanine iodide staining;the changes of mitochondrial respiratory chain complex activity was evaluated by enzyme activity kits;flow cytometry was used to detect the ratio of apoptotic cells;transmission electron microscope was used to observe the ultrastructure of H9C2 cells;Western blot was used to detect the protein changes of mitochondrial 20 k Da outer membrane protein(TOM20),translocase of inner mitochondrial membrane 23(TIM23),presenilins associated rhomboid-like protein(PARL),PINK1,PARKIN and mitofusin 1(Mfn1),mitofusin 2(Mfn2),phosphotyrosine independent ligand for the Lck SH2 domain of 62 k Da(P62),microtubule-associated protein 1 light chain 3 beta(LC3B);the m RNA levels of PINK1 and PARKIN was detected by quantitative polymerase chain reaction;immunoprecipitation assay was used to detect the interaction between PARKIN and ***:Resveratrol could inhibit the proliferation of H9C2 cells in a time-and concentration-dependent manner;however,pretreatment with low cytotoxic resveratrol could reduce the H/R-induced increase in cellular ROS levels,alleviate the loss of mitochondrial membrane potential induced by H/R,inhibit H/R-induced apoptosis of H9C2 cells,and protect the mitochondrial structure and respiratory chain of H9C2 cells from H/R *** could further increase the leve

关键词： resveratrol myocytes cardiac hypoxia PTEN phosphohydrolase Parkinson disease associated proteins mitochondrial autophagy

Ultrahigh performance concrete–properties, applications and perspectives

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Science China(Technological Sciences) 2015年第4期58卷 587-599页

作者： GU Chun Ping YE Guang sun wei School of Materials Science & Engineering Southeast University Microlab Faculty of Civil Engineering and Geosciences Delft University of Technology Jiangsu Key Laboratory of Construction Materials Collaborative Innovation Center for Advanced Civil Engineering Materials

Over the last twenty years,remarkable advances have taken place in the research and application of ultra-high performance concrete(UHPC),which exhibits outstanding mechanical properties and excellent *** has shown great potential for the next generation infrastructure construction from the sustainability point of *** paper will give an overview on UHPC,with particular focus on the properties,applications and *** several decades of development,several types of commercial UHPC materials are available in the market,and the properties of UHPC have been characterized by numerous experimental and field *** speaking,the performance(*** properties and durability)of UHPC is much better than normal concrete(NC)and high performance concrete(HPC).Therefore,the uses of UHPC are growing all over the world,in both fields of new construction and ***,it is still a special material and technology,which is not worldwide *** some application prospects of UHPC are briefly introduced in the paper,and the efforts,which have to be made to turn UHPC into a widespread‘regular’technology,are *** paper aims to help designers,engineers,architects and infrastructure owners to know the capacities of UHPC and thus to increase the applications of this material.

关键词： UHPC characteristics durability applications perspectives

Cretaceous Volcanic Events in Southeastern Jilin Province,China:Evidence from Single Zircon U-Pb Ages

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Acta Geologica Sinica(English Edition) 2008年第6期82卷 1194-1200页

作者： CHEN Yuejun sun Chunlin sun Yuewu sun wei Research Center of Paleontology and Stratigraphy Jilin University Changchun JiIin 130026

Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize Mesozoic volcanic rule in northeastern China. Along with the research of rare Mesozoic biota and extensive Mesozoic mineralization in western Liaoning, a number of researchers have focused on Mesozoic volcanic events. The authors studied the ages of the Cretaceous volcanic rocks in southeastern Jilin Province using single Zircon U-Pb. The result shows that the Sankeyushu Formation volcanic rocks in the Tonghua area are 119.2 Ma in age, the Yingcheng Formation in the Jiutai area 113.4±3.1 Ma, the Jinjiatun Formation in Pinggang Town of Liaoyuan City and the Wufeng volcanic rocks in the Yanji area 103.2±4.7 Ma and 103.6±1 Ma, respectively. Combined with the data of recent publication on volcanic rocks ages; the Cretaceous volcanic events in southeastern Jilin Province can be tentatively subdivided into three eruption periods： 119 Ma, 113 Ma and 103 Ma. The result not only provides important chronology data for subdividing Mesozoic strata in southeastern Jilin Province, establishing Mesozoic volcanic event sequence, discussing geological tectonic background, and surveying the relation between noble metals to the Cretaceous volcanic rocks, but also offers important information of Mesozoic volcanism in northeastern China.

关键词： age of zircon U-Pb volcanic event Cretaceous Jilin Province

Recognition for Frontal Emergency Stops Dangerous Activity Using Nano IoT Sensor and Transfer Learning

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Intelligent Automation & Soft Computing 2023年第7期37卷 1181-1195页

作者： wei sun Zhanhe Du Sports Centre Xi’an Jiaotong UniversityXi’an710049China School of Economics and Management Xi’an University of TechnologyXi’an710054China

Currently,it is difficult to extract the depth feature of the frontal emergency stops dangerous activity signal,which leads to a decline in the accuracy and efficiency of the frontal emergency stops the dangerous ***,a recognition for frontal emergency stops dangerous activity algorithm based on Nano Internet of Things Sensor(NIoTS)and transfer learning is ***,the NIoTS is installed in the athlete’s leg muscles to collect activity ***,the noise component in the activity signal is removed using the de-noising method based on mathematical ***,the depth feature of the activity signal is extracted through the deep transfer learning model,and the Euclidean distance between the extracted feature and the depth feature of the frontal emergency stops dangerous activity signal is *** the European distance is small,it can be judged as the frontal emergency stops dangerous activity,and the frontal emergency stops dangerous activity recognition is *** results show that the average time delay of activity signal acquisition of the algorithm is low,the signal-to-noise ratio of the action signal is high,and the activity signal mean square error is *** variance of the frontal emergency stops dangerous activity recognition does not exceed *** difference between the appearance time of the dangerous activity and the recognition time of the algorithm is 0.15 s,it can accurately and quickly recognize the frontal emergency stops the dangerous activity.

关键词： Frontal emergency stops recognition nano internet of things sensor transfer learning dangerous activity distinguish

A Mathematical Model Based on Supply Chain Optimization for International Petrochemical Engineering Projects

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China Petroleum Processing & Petrochemical Technology 2015年第2期17卷 91-100页

作者： Gao Ning sun wei College of Chemical Engineering Beijing University of Chemical Technology SINOPEC Great Wall Energy and Chemical Co. Ltd.

Based on the study of supply chain(SC) and SC optimization in engineering projects, a mixed integer nonlinear programming(MINLP) optimization model is developed to minimize the total SC cost for international petrochemical engineering projects. A steam cracking project is selected and analyzed, from which typical SC characteristics in international engineering projects in the area of petrochemical industry are summarized. The MINLP model is therefore developed and applied to projects with detailed data. The optimization results are analyzed and compared by the MINLP model, indicating that they are appropriate to SC management practice in engineering projects, and are consistent with the optimal priceeffective strategy in procurement. As a result, the model could provide useful guidance to SC optimization of international engineering projects in petrochemical industry, and improve SC management by selecting more reliable and qualified partner enterprises in SC for the project.

关键词： supply chain optimization model engineering project MINLP

Relationship between chloride diffusivity and pore structure of hardened cement paste

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 360-367页

作者： Guo-wen sun wei sun Yun-sheng ZHANG Zhi-yong LIU Jiangsu Key Laboratory of Construction Materials.Southeast University Nanjing 211189china

Based on effective media theory, a predictive model, relating chloride diffusivity to the capillary pores, gel pores, tortuosity factor, and pore size distribution of hardened cement, is proposed. To verify the proposed model, the diffusion coefficient of chloride ions, the degree of hydration, and peak radius of capillary pores of cement paste specimens were measured. The predicted results for chloride diffusivity were compared with published data. The results showed that the predicted chloride diffusivity of hardened cement paste was in good agreement with the experimental results. The effect of the evolution of pore structures in cement paste on chloride diffusivity could be deduced simultaneously using the proposed model.

关键词： Hardened cement paste Chloride diffusivity Porosity Tortuosity factor Constrictivity Key words: Hardened cement paste, Chloride diffusivity, Porosity, Tortuosity factor, Conslrictivity