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Multi-dimensional project management models for mega-construction companies and their applications

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science china(Technological sciences) 2011年第S1期54卷 118-124页

作者： LIN ZhengHang 1,2,QIANG MaoShan 1,2,TANG WenZhe 1,2,FAN QiXiang 3.&LIU Qiang 4 1 Institute of Project Management and Construction technology,tsinghua University,Beijing 100084,china 2 State Key {3. of Hydraulic and Engineering,tsinghua University,Beijing 100084,china 3.china Three Gorges Corporation,Yichang 443.02,china 4 School of Software,tsinghua University,Beijing 100084,china 1. Institute of Project Management and Construction technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Hydraulic and Engineering Tsinghua University Beijing 100084 China3. China Three Gorges Corporation Yichang 443002 China4. School of Software Tsinghua University Beijing 100084 China

china is undertaking an increasing number of mega-infrastructure projects along with its rapid economic *** participants in these projects,understand how to adapt the proper and efficient management strategies is *** this paper,we propose three distinct models for companies under various background and management requirements,based on sophisticated data analysis and model ***,we successfully committed these models with hydropower development projects and achieved a great progress in enhancing management efficiency.

关键词： project management models mega-construction companies applications hydropower development companies

Self-healing routing: failure,modeling and analysis

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science china(information sciences) 2011年第3期54卷 609-622页

作者： XU MingWei 1,2 , LI Qi 1,2 , YANG Yuan 1,2 , HOU MeiJia 1,2 & PAN LingTao 1,2 1 Department of Computer science, tsinghua University, Beijing 100084, china 2 tsinghua national laboratory for information science and technology (TNList), Beijing 100084, china 1. Department of Computer science Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guarantee fast route convergence under these failures without impacting packet forwarding. During routing convergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus influence network performance. To solve this problem, several improved routing solutions have been proposed. In this paper, we propose the concept and model of self-healing routing and analyze the key problems in current intra-domain and inter-domain self-healing routing protocols after briefly reviewing the characteristics of network failures. We classify the different self-healing solutions into two categories based on their design principles: routing restoration and routing protection, and systematically analyze these different typical solutions. Finally, we discuss several key issues in self-healing routing and propose a hybrid protection and restoration based routing scheme.

关键词： failure intra-domain routing inter-domain routing self-healing routing

Robust AVS audio watermarking

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science china(information sciences) 2010年第3期53卷 607-618页

作者： WANG Yong & HUANG JiWu Guangdong Key laboratory of information Security technology, School of information science and technology, Sun Yat-Sen University, Guangzhou 510275, china 1. Guangdong Key laboratory of information Security technology School of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China

Part Ⅲ of AVS (china Audio and Video Coding Standard) is the first generic audio standard proposed in china and is becoming popular in some applications. For MP3.audio, some effiorts have been made to solve the copyright pirating and malicious modifications by the way of watermarking. To our best knowledge, similar work on the AVS audio has not been explored. In this paper, we present a novel robust watermarking algorithm for AVS audio. We find that the frame type in the AVS coded process can be used as a robust feature for watermarking. Then we design a novel watermarking algorithm which is integrated into the AVS audio coding process. The watermark bits are embedded into the compressed bit stream. At the extracting end, the watermark bits can be extracted from the compressed bit stream directly. This algorithm achieves robustness to decoding/re-coding attacks, and has low computation complexity for both embedding and extracting while preserving the quality of the audio signals.

关键词： AVS audio security problems robust watermarking

Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2, Ge Yuhui1, Cai Yuanfeng2 and Zhang Xuefeng3.1. Faculty of Resources & Environment, Southwest Petroleum University, Chengdu 610500, china 2. State Key laboratory for Endogenic Metal Deposit Research, Nanjing University, Nanjing 210093. china 3. Department of Natural Resources & {3. information, china University of Petroleum, Beijing 102249, china) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China Department of Natural Resources & technology information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 3.3., suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 3. h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3. HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State Key laboratory of Crystal Materials, Shandong University, Jinan 250100, china 2. School of information {3. and Engineering, Shandong University, Jinan 250100, china 3. Department of Chemical Engineering, Light Industry College of Shandong, Jinan 250100, china 4. Key laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of {3. and technology, Wuhan 43.074, china 1. State Key laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of information science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 46.2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2, BI GuangGuo3.& XU WeiYe4 1 College of information science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, {3. 2 Department of Electronic Engineering, City University of Hong Kong, Hong Kong, {3. 3.national Mobile Communications Research laboratory, Southeast University, Nanjing 210096, {3. 4 Department of Communication Engineering, Nanjing Institute of technology, Nanjing 211167, {3. College of information science and technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Electronic Engineering City University of Hong Kong Hong Kong China national Mobile Communications Research laboratory Southeast University Nanjing 210096 China Department of Communication Engineering Nanjing Institute of Technology Nanjing 211167 China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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science china(Technological sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2,SUN HaiTao 3.WU YaSheng 3.&ZHAO ChuanFeng 1,2 1MOE Key laboratory of Petroleum Engineering,china University of Petroleum,Beijing 102249,china 2 Enhanced Oil Recovering Research Center,china University of Petroleum,Beijing 102249,china 3.aculty of Natural Resource&information technology,china University of Petroleum,Beijing 102249,china 1. MOE Key laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 China2. Enhanced Oil Recovering Research Center China University of Petroleum Beijing 102249 China3. Faculty of Natural Resource & Information Technology China University of Petroleum Beijing 102249 China

Influence of CO2 corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2 corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2-H2O *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2 geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

COMPUTER SIMULATION OF RAYLEIGH FADING CHANNELS IN MC-CDMA SYSTEMS

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Journal of Electronics(china) 2007年第5期24卷 577-582页

作者： Han Fangming Zhang Xianda national laboratory of Radar Signal Processing Xidian University Xi＇an 710071 China national laboratory of tsinghua {3. science and technology Department of AutomationTsinghua University Beijing 100084 China

For Multi-Carrier-Code Division Multiple Access （MC-CDMA） systems, it is usually assumed that the fading of the subcarriers is frequency non-selective and independent of each other. This paper shows that the two assumptions are incompatible. In fact, the MC-CDMA signals at each subcarrier undergo fading that are highly correlated. Based on this observation, this paper develops a simulation algorithm for Rayleigh fading channels via frequency-domain correlation functionl which incorporates the Doppler effect simultaneously. Numerical examples are presented to demonstrate the effectiveness of the new algorithm, with the conclusion that the independence assumption of subcarrier fading overrates the system performance.

关键词： Multi-Carrier-Code Division Multiple Access (MC-CDMA) Rayleigh fading Channelsimulation Frequency-domain correlation

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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science china(Technological sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2,WANG DiFeng 3.& ZHANG Yu 4 1 State Key laboratory of information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 43.079,china 2 College of {3.s,Wuhan University of {3. and technology,Wuhan 43.065,china 3.tate Key laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 3.0012,china 4 Spatial information technology Application Research Institute,Changjiang River Scientific Research Institute,Wuhan 43.010,china Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China Wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China State Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China Changjiang River Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion