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Impact of Atmospheric and Oceanic Conditions on the Frequency and Genesis Location of Tropical Cyclones over the Western North Pacific in 2004 and 2010

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Advances in Atmospheric Sciences 2016年第5期33卷 599-613页

作者： Pan song Jiang ZHU Zhong ZHONG Linlin QI Xiaodan WANG College of Meteorology and Oceanography PLA University of Science and TechnologyNanjing 211101 International Center for Climate and Environment Science Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Beijing Institute of Aeronautical Meteorology Beijing 100085

This study examines the impact of atmospheric and oceanic conditions during May–August of 2004 and 2010 on the frequency and genesis location of tropical cyclones over the western North Pacific. Using the WRF model, four numerical experiments were carried out based on different atmospheric conditions and SST forcing. The numerical experiments indicated that changes in atmospheric and oceanic conditions greatly affect tropical cyclone activity, and the roles of atmospheric conditions are slightly greater than oceanic conditions. Specifically, the total number of tropical cyclones was found to be mostly affected by atmospheric conditions, while the distribution of tropical cyclone genesis locations was mainly related to oceanic conditions, especially the distribution of SST. In 2010, a warmer SST occurred west of 140°E, with a colder SST east of 140°E. On the one hand, the easterly flow was enhanced through the effect of the increase in the zonal SST *** strengthened easterly flow led to an anomalous boundary layer divergence over the region to the east of 140°E, which suppressed the formation of tropical cyclones over this region. On the other hand, the colder SST over the region to the east of 140°E led to a colder low-level air temperature, which resulted in decreased CAPE and static instability energy. The decrease in thermodynamic energy restricted the generation of tropical cyclones over the same region.

关键词： tropical cyclone SST numerical simulation western North Pacific

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EXPERIMENTAL STUDIES ON DYNAMIC PROPAGATION OF CRACKS UNDER BIAXIAL COMPRESSION

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Acta Mechanica Solida Sinica 1994年第3期7卷 211-220页

作者： Yu, Hengwen song, Jinliang Feng, Deyi Jian, Chun Univ of Science & Technology of China Hefei China

This paper deals with the initiation and non-coplaner propagation of cracks under biaxial compression. The running process of the propagating cracks is successfully recorded with the method of dynamic photoelasticity. A series of important fracture parameters such as cracks propagating velocity, critical opening loading and initial angle of cracks growth under biaxial compression is calculated. Results show that the stress field in front of the non-closed crack tip under biaxial compression is a mixed-mode singular field, the dynamic propagation of the new tensile cracks is just stable and shows distinct stages, but the unstable crack appears under high loads and results in the rupture of the matrix.

关键词： Failure (mechanical) Fracture Fracture mechanics Loads (forces) Photoelasticity Stability Stresses Velocity

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A Novel Human Action Recognition Algorithm Based on Decision Level Multi-Feature Fusion

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China Communications 2015年第S2期12卷 93-102页

作者： song Wei LIU Ningning YANG Guosheng YANG Pei School of Information and Engineering Minzu University of China School of Electronic Information and Engineering Beijing Jiaotong University

In order to take advantage of the logical structure of video sequences and improve the recognition accuracy of the human action, a novel hybrid human action detection method based on three descriptors and decision level fusion is proposed. Firstly, the minimal 3D space region of human action region is detected by combining frame difference method and Vi BE algorithm, and the three-dimensional histogram of oriented gradient(HOG3D) is extracted. At the same time, the characteristics of global descriptors based on frequency domain filtering(FDF) and the local descriptors based on spatial-temporal interest points(STIP) are extracted. Principal component analysis(PCA) is implemented to reduce the dimension of the gradient histogram and the global descriptor, and bag of words(BoW) model is applied to describe the local descriptors based on STIP. Finally, a linear support vector machine(SVM) is used to create a new decision level fusion classifier. Some experiments are done to verify the performance of the multi-features, and the results show that they have good representation ability and generalization ability. Otherwise, the proposed scheme obtains very competitive results on the well-known datasets in terms of mean average precision.

关键词： human action recognition feature fusion HOG3D

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Evaluation of the individual allocation scheme and its impacts in a dynamic global vegetation model

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Atmospheric and Oceanic Science Letters 2016年第1期9卷 38-44页

作者： song Xiang ZENG Xiao-Dong LI Fang International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology

The strategies of plant growth play an important role not only in ecosystem structure,but also in global carbon and water *** this work,the individual carbon allocation scheme of tree PFTs and its impacts were evaluated in China with Institute of Atmospheric Physics-Dynamic Global Vegetation Model,version 1.0（IAP-DGVM1.0）as a *** results showed that,as individual growth,the current scheme tended to allocate an increasing proportion of annual net primary productivity（NPP）to sapwood and decreasing proportions to leaf and root accordingly,which led to underestimated individual leaf biomass and overestimated individual stem *** biases resulted in an overestimation of total ecosystem biomass and recovery time of mature forests,and an underestimation of ecosystem NPP and tree leaf area index in China.

关键词： IAP-DGVM 1.0 individual allocation scheme biomass carbon residence time China

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Credit Risk Prediction Based on Improved ADASYN Sampling and Optimized LightGBM

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Journal of Social Computing 2024年第3期5卷 232-241页

作者： Mei song He Ma Yi Zhu Mengdi Zhang the School of Computer Science and Technology Jiangsu Normal UniversityXuzhou 221116China the Management Science and Technology Center Jiangsu Normal UniversityXuzhou 221116China

A credit risk prediction model named KM-ADASYN-TL-FLLightGBM(KADT-FLightGBM)is proposed in this ***,to overcome the limitation of traditional sampling methods in dealing with imbalanced datasets,an improved ADASYN sampling with K-means clustering algorithm is ***,the Tomek Links method is used to filter the generated ***,an utilized an optimized LightGBM algorithm with the Focal Loss is employed to training the model using the datasets obtained by the improved ADASYN ***,the comparative analysis between the ensemble model and other different sampling methodologies is conducted on the Lending Club *** results demonstrate that the proposed model effectively minimizes the misclassification of minority classes in credit risk prediction and can be used as a reference for similar studies.

关键词： imbalance data credit risk prediction Focal Loss adaptive hybrid sampling

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Expression of cyclooxygenase-2 and clinicopathologic features in human gastric adenocarcinoma

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World Journal of Gastroenterology 2003年第2期9卷 250-253页

作者： Ying-WeiXue Qi-FanZhang Zhi-BingZhu QiWang song-BinFu DepartmentofGeneralSurgery TheThirdClinicalHospitalHarbinMedicalUniversityHarbin150040HeilongjiangProvinceChina LaboratoryofMedicalGeneticsandDepartmentofBiology CollegeofBasicMedicalSciencesHarbinMedicalUniversityHarbin150086HeilongjiangProvinceChina

AIM: To study the expression of cyclooxygenase-2 (COX-2)gene in gastric cancer and the relationship between COX-2expression and clinicopathologic features of gastric ***: With reference to the expression of β-actin gene,COX-2 mRNA level was examined in cancerous tissues andadjacent noncancerous mucosa from 33 patients bysemiquantitative reverse transcription- polymerase chainreaction (RT-PCR). Quantitation of relative band Adj volumecounts was performed using molecular Analyst for windowssoftware. The COX-2 index was determined from the band Adjvolume counts ratio of COX-2 to constitutively expressed ***: The COX-2 index in gastric carcinoma wassignificantly higher than that in normal mucosa (0.5966±0.2659vs 0.2979+0.171, u=5.4309, P＜0.01). Significantly higherexpression of COX-2 mRNA was also observed in patientswith lymph node involvement than that in those without(0.6775±0.2486 vs 0.4105±0.2182, t=2.9341, P＜0.01).Furthermore, the staging in the UICC TNM classificationsignificantly correlated with COX-2 overexpression (F＝3.656,P＜0.05), the COX-2 index in stage Ⅲ and IV was significantlyhigher than those in stage Ⅰ and Ⅱ(q=3.2728 and q=3.4906, P＜0.05). The COX-2 index showed no correlationwith patient's age, sex, blood group, tumor location, grosstyping, depth of invasion, differentiation, and the greatesttumor dimension (P＞0.05).CONCLUSION: Expression of COX-2 mRNA in gastriccarcinoma was significantly higher, which may enhancelymphatic metastasis in patients with gastric carcinoma. Thestaging in the UICC TNM classification was significantlycorrelated with COX-2 over-expression. COX-2 may contributeto progression of tumor in human gastric adenocarcinoma.

关键词：环氧合酶-2 胃腺癌临床病理学 β-连接素 RT-PCR

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Damage Action of Alkali-resistant Glass Fiber in Cement-based Material

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 761-765页

作者：吴会军 ZHAO Jing WANG Zhongchang song Ting School of Civil and Safety Engineering Dalian Jiaotong University

The compressive strength and flexural strength with the same strength class cement mortar of the alkali-resistant glass fiber cement mortar were tested in standard and hot-water curing condition, and the damage mechanism of alkali-resistant glass fiber was studied. The interaction mechanisms of the chemical erosion and physical injury in different curing conditions were studied in order to summarize the damage mechanism of alkali-resistant glass fiber in cement-based materials, and chloride diffusivity coefficient and porosity of cement mortar were tested in the different curing conditions. The experimental results are that the strength of cement based materials and fiber cement slurry interface zone were closely related, and heat curing could accelerate the hydration of cement, but inevitably enlarge the defect.

关键词： alkali-resistant glass fiber cement-based materials damage heat curing condition micro-structure

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Laser melted oxide ceramics:Multiscale structural evolution with non-equilibrium features

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Journal of Materiomics 2019年第3期5卷 436-445页

作者： Lu song Jing Ma Qinghua Zhang Zhijian Shen State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm UniversityStockholm10691Sweden

Compared with the versatility in metal industry,application of laser on oxide ceramics is quite limited due to the intrinsic features of ceramics and limited understanding in laser-ceramic interaction mechanism,especially for high-energy laser that causes melting of *** this research,a study into general behaviors of several oxide ceramics melted by laser under inert atmosphere is *** factors in determining state transformation,chemical reduction and phase structure are summarized,with further investigation into the evolution in microstructure at multiscale and the corresponding novelty and *** is found that laser melting does show great potential in introducing deep reduction,unique microstructure,and notable increase in structure complexity and total entropy,and those features could contribute to some unconventional functional performance with brand-new structure-property relationship.

关键词： Laser Oxide ceramic Heterogeneity Defects Non-equilibrium

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Controlling factors for large gas field formation in thrust belt of Kuqa coal derived hydrocarbon foreland basin

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Chinese Science Bulletin 2002年第S1期47卷 55-61页

作者： song Yan JIA Chengzao ZHAO Mengjun TIAN Zuoji Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China PetroChina Beijing 100011China

Kuqa depression is a foreland basin developedwith Mesozoic-Triassic-Jurassic coal-bearing formation. Theresearch results of the coal-derived hydrocarbon forelandbasins in Kuqa depression indicated that the coal-bearingformation can be the rich sources for generating gas becauseof their thickness and rich source rocks with gas-generatingpredominant kerogen. Although the foreland thrust beltmainly acting in compression is very complicated, integrallarge structural traps can be formed. Moreover, the thrustbelt can act as the passage for communication with deepsource rocks. The high quality gypsolish and gypseous mud-stone cap rock developed in the upper formation is the keyfor the formation of the large gas field. The late formation ofreservoirs in the large gas fields depended on the hydrocar-bon-generating history controlled by the foreland basin andthe developing process of foreland thrust belt.

关键词： foreland basin thrust belt coal-bearing formation large gas field.

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Assimilation of High Frequency Radar Data into a Shelf Sea Circulation Model

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Journal of Ocean University of China 2014年第4期13卷 572-578页

作者： XU Jiangling HUANG Juan GAO song CAO Yajing North China Sea Marine Forecast Center of the State Oceanic Administration

High Frequency(HF) radar current data is assimilated into a shelf sea circulation model based on optimal interpolation(OI) method. The purpose of this work is to develop a real-time computationally highly efficient assimilation method to improve the forecast of shelf current. Since the true state of the ocean is not known, the specification of background error covariance is arduous. Usually, it is assumed or calculated from an ensemble of model states and is kept in constant. In our method, the spatial covariances of model forecast errors are derived from differences between the adjacent model forecast fields, which serve as the forecast tendencies. The assumption behind this is that forecast errors can resemble forecast tendencies, since variances are large when fields change quickly and small when fields change slowly. The implementation of HF radar data assimilation is found to yield good information for analyses. After assimilation, the root-mean-square error of model decreases significantly. Besides, three assimilation runs with variational observation density are implemented. The comparison of them indicates that the pattern described by observations is much more important than the amount of observations. It is more useful to expand the scope of observations than to increase the spatial interval. From our tests, the spatial interval of observation can be 5 times bigger than that of model grid.

关键词： data assimilation current radar shelf circulation model

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