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Nonlinear Characterization Method of Fracturing Stimulation Scale on Heterogeneous Reservoir by Combining Logging and Seismic Data
DU Shuheng, SHI Yongmin, XU Qi, FANG Yuanyuan, SHENG Yingshuai
Acta Scientiarum Naturalium Universitatis Pekinensis    2016, 52 (2): 241-248.   DOI: 10.13209/j.0479-8023.2015.079
Abstract1089)   HTML    PDF(pc) (3041KB)(848)       Save

After two infilling adjustment and repeated fracturing on the third type of Chaoyanggou oil field, effective drive systems are still unable to be established in part of the reservoirs, and the measure effect and oil recovery degree is poor. Considering the insufficient understanding on fracture extending and fracturing stimulation scale of heterogeneous reservoir, 3D modeling on reservoir are performed by combining logging and seismic data and the asymmetric cracks are predicted based on elastic theory. Concepts named “relative stress” and “stimulation ratio” are raised, and the nonlinear relation between these two parameters is given. The scale of “relative stress” which could produce the supporting fracture is confirmed, and the fracturing stimulation scale could be judged. It would play important role on the layers selecting during the late development of oilfield and eventually to improve oilfield recovery degree.

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Multi-strategy Approach for Fine-Grained Sentiment Analysis of Chinese Microblog
OUYANG Chunping,YANG Xiaohua,LEI Longyan,XU Qiang,YU Ying,LIU Zhiming
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract850)      PDF(pc) (499KB)(703)       Save
Fine-grained sentiment analysis of Chinese microblog is investigated and a method of multi-strategy fusion is proposed. Firstly, the authors apply naive Bayesian to identify sentiment or non-sentiment about microblog. Secondly, based on emotion ontology, a method for how to form 21 sentiment features vectors of microblog is presented. At last, fine-grained sentiment of microblog is classified based on SVM and KNN respectively. Experiment results show that multi-strategy fusion is better than a single method, in addition, “NB+SVM” strategy is better than “NB+KNN” strategy.
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Land Resource Conflicts and Coordination in Fast Urbanized Coastal Zone: A Case Study of the Shandong Peninsula
XU Xuegong,PENG Huifang,XU Qinzheng
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract841)            Save
Coastal zone is an interface region by geo-sphere, hydrosphere, atmosphere and biosphere, and also mostly affected by human activities. Driven by urbanization, population and economic activities are fast concentrating in coastal zones, resulting in a series of land use conflicts, especially in the developing countries at economic transition time. Shandong Peninsula is located in the East China. There are six big cities along the coast of the Peninsula. They are Tsingdao, Yantai, Weihai, Rizhao, Weifang and Dongying cities. Along with fast urbanization, there are large changes in land use and land covers. From 1990 to 2003, the cultivated land all decreased in every city, other decreased land use types were grassland, water area and unused land. At the same time, constructed land, garden land and woodland increased. A series of land use conflicts issues must be envisaged. The mostly expressive are three types of conflicts: those between expanding constructed land and decreased cultivated land; those between land resource utilization and conservation; and those between increasing demand for land and degrading land quality. All in all, they reflect the fundamental conflict between short-term economic development and long-run food/ecosystem security. This paper puts forward the approach to coordinate land use conflicts: (1) updating concepts—intensive land use and smart growth, (2) planning order—construct regional security pattern firstly, (3) multi-proposals—land gross control combining rigidity and flexibility, (4) space allocation—functional restriction and compatibility, (5) mechanism and policy—communicate, participate, equitable and all winning. Through controlling the gross area of various types of land uses, improving land use efficiency, and using flexible policies, we attempt to resolve the conflicts between fast urbanization and resultant resource and environment problems, so as to realize integrated and coordinated coastal management.
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Comparison of Structures between Crystals of Bar-headed Goose Hemoglobin Grown in Space and Earth
LIANG Yuhe,ZHA Zheng,HUA Ziqian,LIANG Xue,XU Qian,LU Guangying
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract645)            Save
During the experiment of protein crystal growth in space carried by Chinese re-entry capsule FSW-2, the crystals of Bar-headed Goose hemoglobin suitable for X-ray analysis were obtained both in space and earth as contrast group. The diffraction data of both crystals were collected, and the structures were solved using molecule replacement methods. The comparison of structures in space and earth indicate that, (1) The interactions among molecules in crystal and subunits of molecule in space is weakened relative to the crystal on earth, (2) There is a contact in the α1β2“switch region” of molecule in space, between α1 Thr41CG2 and β2 His97ND1, which doesn't appear in earth.
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Crystal Growth of Hemoglohin of Bar-headed Goose in Space
HUA Ziqian,LIANG Xue,LIANG Yuhe,XU Qian,KUANG Bao,LI Huikuang,WEI Xincheng
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract771)            Save
The hemoglohin of Bar-headed Goose has been choosen as investigation of Crystal growth in space by vapour diffusion method. Two times experiments under microgravity was done in Chinese re-entry capsule FSW-2, The small crystals have been obtained at first time and the big crystals suitable for X-ray analysis after improving the condition of crystalligation. The suggestion by X-ray experiment could be made as follows. (1) In comparison with the crystals grown on earth, the crystals grown in space are rather perfect, the resolution of crystal in space is by 0.06nm higher than the crystal on earth. (2) The crystals grown in space favour packing in orthorhombic crystal system and the parameter of unit cell in one direction is about 0.8nm longer than the crystals on earth.
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