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Node ordinal encoded genetic algorithm for the optimal allocation of water resources

Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2. SHEN Zhenyao1 and LI Jianqiang3.1. State Key Laboratory of Water Environment Simulation, School of Environment, beijing Normal University, beijing 100875, China 2. Key Laboratory for Water and Sediment Sciences Ministry of Education, School of Environment, beijing Normal University, beijing 100875, China 3. Water Resources and Hydropower Planning and Design General institute, MWR, beijing 100011, China) State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University Beijing 100875 China Water Resources and Hydropower Planning and Design General institute MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

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Modeling of elastic wave propagation on a curved free surface using an improved finite-difference algorithm

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 633-648页

作者： WANG Xiuming1,3.& ZHANG Hailan2.1. CSIRO Petroleum, ARRC, PO BOX 113., Technology Park, Bentley, WA 6102. Australia 2. {2. of Acoustics, Chinese Academy of Sciences, beijing 100080, China 3. Present address: {2. of Acoustics, Chinese Academy of Sciences, beijing 100080, China 1. CSIRO Petroleum ARRC Technology Park PO BOX 1130 6102 Bentley WA Australia 2. institute of Acoustics Chinese Academy of Sciences 100080 Beijing China

Based on existing direct and imaging methods of a staggered finite-difference scheme, an improved algorithm for staggered finite-difference is proposed to implement rugged topographic free boundary conditions. This method assumes that the free surface can be implemented with horizontal and vertical free surface segments and their corners; the free surface passes through the grid points of shear stress components, instead of the normal stress components. Imaging is carried out for stress components in both horizontal and vertical directions, thus increasing the accuracy. To update particle- velocities, imaging and updating are first performed in the horizontal direction, and then in the vertical direction. The numerical results for elastic flat horizontal free surface with the imaging method and those for flat free surfaces of various slope angles with the proposed method are compared, and are shown to be in good agreement. The advantage of the proposed method is that only the stresses are dealt with in implementing the free surface into the staggered algorithm, which improves computation efficiency.

关键词： elastic wave simulation, curved free surface, staggered finite-difference, algorithm stability.

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Formal analysis and design of multi-party fair exchange protocols

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Science in China(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2.3.& LI Gaicheng1,3.1. Engineering Research Center for Information Security Technology, {2. of Software, Chinese Academy of Sciences, beijing 100080, China 2. beijing Zhongke Ansheng Corporation of Information Technology, beijing 100080, China 3. Graduate School of the Chinese Academy of Sciences, beijing 10003., China 1. Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. beijing Zhongke Ansheng Corporation of Information Technology Beijing 100080 China 3. Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

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Timing and history of marine hydrocarbon accumulation in Tarim craton

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Chinese Science Bulletin 2002年第S1期47卷 120-127页

作者： ZHAO Jingzhou~(1,2. & LI Qiming~3.1. Department of Petroleum Geology, Xi’an Petroleum institute, Xi’an 710065, China 2. Research institute of Petroleum Exploration and Development, PetroChina, {2. 100083. China 3. Tarim Oilfield Company, Kuerle, Xinjiang 841000, China Xian Petr Inst Dept Petr Geol Xian 710065 Peoples R China PetroChina Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China Tarim Oilfield Co Xinjiang 841000 Peoples R China

Based on the analyses of hydrocarbon inclu-sions, K-Ar dating of authigenic illites and oil/gas-watercontact retrospection as well as other methods, the marineprimary reservoirs in the cratonic region of the Tarim Basinare found to have been formed in the late Caledonian toearly Hercynian, late Hercynian, and Himalayan, and oil andgas adjusted and redistributed in the Yanshanian (Jurassic toCretaceous) and Himalayan (Tertiary). The analyses alsoshow that the remaining primary oil accumulations aremostly formed in the late Hercynian, and the secondary oilreservoirs resulted from the adjustment and redistribution ofthe earlier accumulations during the Yanshanian and Hima-layan (especially late Himalayan), of which the Himalayan isalso the major stage of gas accumulation. The primary oilreservoirs formed in the late Hercynian mostly occur withinthe Paleozoic formation, whereas the secondary reservoirsformed in the Himalayan in the Mesozoic. The late adjust-ment and redistribution of reservoirs in the craton region ofthe Tarim Basin is ubiquitous because of the intensified tec-tonic movements since the Mesozoic, especially Cenozoic andintrusion of the high- to over-mature gas. Furthermore, thelower amplitude of reservoirs in the craton region also makesthem easier to be adjusted and redistributed. Therefore, theremaining paleo-uplift and palaeo-slope developed in rela-tively stable tectonic regions are the main potential areas forthe middle-large marine reservoirs in the Tarim Basin.

关键词： Tarim Basin craton geochronology of hydrocarbon accumulation history of hydrocarbon accumulation marine reservoir primary reservoir secondary reservoir.

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Zonal propagation of kinetic energy and convection in the South China Sea and Indian monsoon regions in boreal summer

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Science China Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2.,HE Jinhai 2.,TAO Shiyan 3.& JIN Zuhui 3.1.Chinese Academy of Meteorological Sciences,{2. 100081,China 2.Nanjing institute of {2.,Nanjing 2.0044,China 3.institute of Atmospheric Physics,Chinese Academy of Sciences,{2. 1.002.,China 1. Chinese Academy of Meteorological Sciences 100081 Beijing China 2. Nanjing institute of meteorology 210044 Nanjing China 3. Chinese Academy of Sciences Institute of Atmospheric Physics 100029 Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South China Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

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Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science China(Technological Sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2. GU Yidong3. LIN Baojun3.& GUO Jiong3.1. Center for Space Science and applied Research, Chinese Academy of Sciences, beijing 100080, China 2. Graduate School of the Chinese Academy of Sciences, beijing 10003., China 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, beijing 100080, China Correspondence should be addressed to L Congmin 1. Center for Space Science and applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

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Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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Science China Earth Sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, LIU Hongbin2. LIANG Eryuan1, FANG Xiuqi3.& WANG Lili1 1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, {2. 100101, China 2. National Climate Center, {2. 100081, China 3. {2. Normal University, {2. 100875, China institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD152.—163. and 193.—2.01, whereas dry intervals in 142.—1519 and 163.—1741. In ad- dition, the magnitude in precipitation variation was lower before 143. with about 15 mm, but it increased to 3. mm during the period of 143. to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 2.st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3.& WANG Huijun2.1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, Chinese Academy of Sciences,{2., China 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, China 3. Graduate University of the Chinese Academy of Sciences, {2. 100049, China 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

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Density functional theory study of the reaction paths of reactions of CH3.（O）O2.radicals with HO2.in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1,2., ZHANG Shaowen~1 and LI Qianshu~1**(1. State Key Laboratory of Explosion Science and Technology, beijing institute of Technology, beijing 100081, China 2. beijing institute of Education, beijing 100044, China) [a]State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China [b]beijing institute of Education Beijing China

A DFT study on the reactions between CH_3.（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3.（O）O_2.) and triplet O_2.olecule. The CH_3.（O）O_2. can further convert into CH_3.（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

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Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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Science China(Technological Sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2. CAI Hongnian1, ZHANG Xinming2. WANG Fuchi1 & TAN Chengwen1,3.1. School of Material Science and Engineering, beijing {2. of Technology, beijing 100081, China 2. School of Material Science and Engineering, Central South University, Changsha 410083. China 3. School of Material Science and Engineering, beijing University of Aeronautics and Astronautics, beijing 100083. China 1. School of Material Science and Engineering Beijing Institute of Technology Beijing 100081 China 2. School of Material Science and Engineering Central South University Changsha 410083 China 3. School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112.and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

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