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CONDITIONS FOR UNIFORMLY NON-CONFOUNDING OF CAUSAL DISTRIBUTION EFFECTS OVER MULTIPLE COVARIATES

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Journal of Systems Science & Complexity 2010年第4期23卷 796-803页

作者： Xueli WANG School of Science,Beijing university of posts and {2.,Beijing 100876,china. School of Science Beijing University of Posts and Telecommunications

Causation is a distinct concept from association and more important than association inepidemiologic *** paper proposes the concept of uniform non-confounding for causal distributioneffects over multiple covariates,and gives the sufficient conditions for uniform non-confoundingover a covariate set C including confounders or non-confounders,and also shows the conditions forconditionally non-confounding in the *** these conditions can be tested by observeddata.

关键词： Causal distribution effect confounding covariates uniform non-confounding

On the Bandwidth of RFT Interconnection Network in the Presence of Faulty Components

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The Journal of china Universities of posts and {2. 1995年第2期2卷 69-77页

作者： Deng Yaping(Department of Computer, chongqing university of posts and telecommunications, chongqing 630065, P. R.{2.)

In this paper, the performance is analyzed, of multiprocessor systems with RFT (Reliable andFault-Tolerant) interconnection network in the presence of faulty components. Two models are discussed andestimates for the bandwidth of these systems are provided, and then the expected degradation in the perform-ance of systems in the presence of faulty components through some numerical results is compared.

关键词： multiprocessor bandwidth transition probability state processing power

Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 college of Geographical Science, chongqing Normal {2., chongqing 400047, china 2.college of Resources and Environmental Science, chongqing {2., chongqing 400044, china 3 college of Resources Science & Technology, Beijing Normal {2., Beijing 100875, china college of Geographical Science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental Science Chongqing University Chongqing 400044 China college of Resources Science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Hyperstar: A New Interconnection Topology

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The Journal of china Universities of posts and {2. 1998年第2期5卷 10-18页

作者： Mikhail A. Rakov (Visiting Research Professor, chongqing university of posts and telecommunications, chongqing,400054,P.P.{2.)

A novel approach to the problem of optimal interconnection of nondes,for example, interconnect in an integrated circuit, modules in a multiprocessor system,or subscribers to a communication network is proposed. The method is based on a special mathematical structure from number theory-Perfect Difference Sets (PDS). Using this approach, the performance of electronic, computer and telecommunication systems can be improved dramatically. The main concept,algorithm for designing optimal connecting graph, and a resulting topological structure of Hyperstar interconnections have all been fully developed.

关键词： intereonnection topologies PDS Hyperstar

Aurora B facilitates cholangiocarcinoma progression by stabilizing c-Myc

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Animal Models and Experimental Medicine 2024年第05期 626-640页

作者： Ke Liu Xuxuan Zhou Fei Huang Lihao Liu Zijian Xu chongqing Gao Keke Zhang Jian Hong Nan Yao Guohua Cheng college of Pharmacy Jinan University Department of Pathophysiology School of Medicine Jinan University School of Medicine Jinan University

Background: Cholangiocarcinoma(CCA), a malignancy that arises from biliary epithelial cells, has a dismal prognosis, and few targeted therapies are available. Aurora B, a key mitotic regulator, has been reported to be involved in the progression of various tumors, yet its role in CCA is still ***: Human CCA tissues and murine spontaneous CCA models were used to assess Aurora B expression in CCA. A loss-of-function model was constructed in CCA cells to determine the role of Aurora B in CCA progression. Subcutaneous and liver orthotopic xenograft models were used to assess the therapeutic potential of Aurora B inhibitors in ***: In murine spontaneous CCA models, Aurora B was significantly upregulated. Elevated Aurora B expression was also observed in 62.3% of human specimens in our validation cohort(143 CCA specimens), and high Aurora B expression was positively correlated with pathological parameters of tumors and poor survival. Knockdown of Aurora B by siRNA and heteroduplex oligonucleotide(HDO)or an Aurora B kinase inhibitor(AZD1152. significantly suppressed CCA progression via G2.M arrest induction. An interaction between Aurora B and c-Myc was found in CCA cells. Targeting Aurora B significantly reduced this interaction and accelerated the proteasomal degradation of c-Myc, suggesting that Aurora B promoted the malignant properties of CCA by stabilizing c-Myc. Furthermore, sequential application of AZD1152.or Aurora B HDO drastically improved the efficacy of gemcitabine in ***: Aurora B plays an essential role in CCA progression by modulating c-Myc stability and represents a new target for treatment and chemosensitization in CCA.

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Instability of forced flow in a rotating cylindrical pool with a differentially rotating disk on the free surface

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Science china(Technological Sciences) 2010年第9期53卷 2477-2488页

作者： WU ChunMei & LI YouRong college of Power Engineering,chongqing {2.,chongqing 400044,china 1. college of Power Engineering Chongqing University Chongqing 400044 China

The instability of forced flow in a rotating cylindrical pool with a differentially rotating disk on the free surface is investigated through a series of unsteady three-dimensional numerical *** results show that the basic flow state of this system is axisymmetric and steady,but has rich structures at the meridian ***,when the rotation Reynolds number exceeds a critical value,the flow will undergo a transition to three-dimensional oscillatory flow,characterized by the velocity fluctuation waves traveling in the azimuthal *** main characteristics of the flow patterns are presented,including the propagating direction,velocity,amplitude and wave number,which depend on the rotation rates and directions of the disk and the cylindrical pool,and the critical conditions for the onset of oscillatory flow are also *** the case of disk-only rotation,the centrifugal instability is responsible for the flow transition,and when the disk isoand counter-rotates with the cylindrical pool,the mechanisms for the transition are elliptic and of circular shear instabilities,respectively.

关键词： rotation flow transition flow instability

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2.1. college of Surveying and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000,{2. 2. college of Geographic Sciences, chongqing Normal university, chongqing 400047,{2. [a] college of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] college of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, china, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62.; and that higher than 60% accounts for 2.%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

Stress distribution rule of roadway affected by overhead mining in gently inclined coal seams group

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中国有色金属学会会刊：英文版 2011年第S3期21卷 529-535页

作者： KANG Qin-rong1, 2. TANG Jian-xin1, 2. HU Hai1, 2. ZHANG Wei-zhong1, 3 1. college of Resource and Environmental Sciences, chongqing {2., chongqing 400030, china 2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, chongqing {2., chongqing 400030, china 3. School of Safety Science and Administration, Zhongnan {2. of Economics and Law, Wuhan 430074, china [a] college of Resource and Environmental Sciences Chongqing University Chongqing 400030 China [b] State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University Chongqing 400030 China [c] School of Safety Science and Administration Zhongnan University of Economics and Law Wuhan 430074 China

In light of the severe deformation and destruction of the district raise tunnel in the mining area at the northern part of the Lubanshan colliery, by the theoretic analysis and numerical simulation, both the mining stress distribution in seams group and the deformation and destruction mechanism of floor district raise were investigated. The results show that, at the maximum vertical distance of 40 m, the abutment stress has an influence on the recovery of 2. and 3# coal seam and 8# coal seam at distance of 30 m. As a result, the recovery of 8# is rather than those of 2. or 3# coal seam, which contributes to the deformation and destruction of the district raise surrounding rock. The major factors affecting the abutment stress include the mining depth, mining height, residual gob space, adjacent working faces and short spacing coal seam recovery.

关键词： coal seams group stress distribution district raise surrounding rock deformation and destruction abutment stress

Secure coverage-preserving node scheduling scheme using energy prediction for wireless sensor networks

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The Journal of china Universities of posts and {2. 2010年第5期17卷 100-108页

作者： LI Zhi-yuan,WANG Ru-chuan. college of Computer,Nanjing university of {2. and telecommunications,Nanjing 2.0003,china [a] college of Computer Nanjing University of Posts telecommunications Nanjing 210003 China

With the fast development of the micro-electro-mechanical systems （MEMS）,wireless sensor networks （WSNs） have been extensively *** of the studies focus on saving energy consumption because of restricted energy supply in ***-based node scheduling scheme is commonly considered as one of the most energy-efficient ***,it is not always so efficient especially when there exist hot spot and network attacks in *** this article,a secure coverage-preserved node scheduling scheme for WSNs based on energy prediction is proposed in an uneven deployment *** scheme is comprised of an uneven clustering algorithm based on arithmetic progression,a cover set partition algorithm based on trust and a node scheduling algorithm based on energy *** results show that network lifetime of the scheme is 350 rounds longer than that of other scheduling ***,the scheme can keep a high network coverage ratio during the network lifetime and achieve the designed objective which makes energy dissipation of most nodes in WSNs balanced.

关键词： wireless sensor networks secure energy-efficient coverage node scheduling cover set energy prediction