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Competent predicate abstraction in model checking

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Science China(information Sciences) 2011年第2期54卷 258-267页

作者： LI Li1,2.3, SONG XiaoYu4. GU Ming2.3 & LUO XiangYu2.3 1Department of Computer Science & Technology, Tsinghua university, {2. 100084. China 2.ey Laboratory for {2. System Security, Ministry of Education of China, {2. 100084. China 3{4. of Software, Tsinghua university, {2. 100084. China 4.epartment of ECE, Portland State university, Portland, Oregon 972.7, USA 1. Department of Computer Science & Technology Tsinghua University Beijing 100084 China2. Key Laboratory for Information System Security Ministry of Education of China Beijing 100084 China3. School of Software Tsinghua University Beijing 100084 China4. Department of ECE Portland State University Portland Oregon 97207 USA

The paper presents a new approach to computing the abstract state and a maximum weight heuristic method for finding the shortest counter-example in verification of imperative programs. The strategy is incorporated in a verification system based on the counterexample-guided abstraction refinement method. The proposed method slashes both the size of the abstract state space and the number of invokes of a decision procedure. A number of benchmarks are employed to evaluate the effectiveness of the approach.

关键词： program model checking predicate abstraction weight heuristic

Limitation of fault-sealing and its control on hydrocarbon accumulation——An example from the Laoyemiao Oilfi eld of the Nanpu Sag

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Petroleum Science 2008年第4期5卷 295-301页

作者： Jiang Zhenxue Dong Yuexia Li Hongyi Liu Luofu Liu Guangdi Li Xiaoying Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Research Institute of exploration and Development Jidong Oilfield PetroChina Tangshan Hebei 063004 China school of Resources and information Technology China University of Petroleum Beijing 102249 China

Based on previous studies on the internal structures of fault belts, the fault belts in the Laoyemiao Oilfield of the Nanpu Sag can be divided into three units, a crushed zone, an upper induced fracture zone and a lower induced fracture zone according to the log response characteristics. The upper induced fracture zone is characterized by the development of pervasive fractures and has a poor sealing or non-sealing capability. It therefore can act as pathways for hydrocarbon migration. The lower induced fracture zone consists of fewer fractures and has limited sealing capability. The crushed zone has a good sealing capability comparable to mudstone and can thus prevent lateral migration of fluid. Through physical modeling and comparing laboratory data with calculated data of oil column heights of traps sealed by faults, it is concluded that the fault-sealing capability for oil and gas is limited. When the oil column height reaches a threshold, oil will spill over from the top of reservoir along the lower induced fracture zone under the action of buoyancy, and the size of reservoir will remain unchanged. Analysis of the formation mechanisms of the fault-sealed reservoirs in the Nanpu Sag indicated that the charging sequence of oil and gas in the reservoir was from lower formation to upper formation, with the fault playing an important role in oil and gas accumulation. The hydrocarbon potential in reverse fault-sealed traps is much better than that in the consequent fault-sealed traps. The reverse fault-sealed traps are favorable and preferred exploration targets.

关键词： Limitation of fault-sealing fault belt oil column height hydrocarbon accumulation Nanpu Sag

Perceptual video hashing robust against geometric distortions

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Science China(information Sciences) 2012年第7期55卷 1520-1527页

作者： XIANG ShiJun 1,4.,YANG JianQuan 2.& HUANG JiWu 3 1 school of {2. Science and Technology,Jinan {2.,Guangzhou 510632.China 2.Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences,Shenzhen 518055,China 3 school of {2. Science and Technology,Sun Yat-sen {2.,Guangzhou 5102.5,China 4.State Key Laboratory of {2. Security,Institute of Software,Chinese Academy of Sciences,beijing 10004.,China 1. school of information Science and Technology Jinan University Guangzhou 510632 China4. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100049 China2. Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China3. School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China

In this paper,we propose a robust perceptual hashing algorithm by using video luminance histogram in *** underlying robustness principles are based on three main aspects:1) Since the histogram is independent of position of a pixel,the algorithm is resistant to geometric deformations; 2. the hash is extracted from the spatial Gaussian-filtering low-frequency component for those common video processing operations such as noise corruption,low-pass filtering,lossy compression,etc.; 3) a temporal Gaussian-filtering operation is designed so that the hash is resistant to temporal desynchronization operations,such as frame rate change and *** a result,the hash function is robust to common geometric distortions and video processing *** results show that the proposed hashing strategy can provide satisfactory robustness and uniqueness.

关键词： video hashing geometric distortion histogram Gaussian filtering

Relaying Selection with Network-coded Cooperative Protocols in Aeronautical Communications

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Chinese Journal of Aeronautics 2010年第1期23卷 75-83页

作者： Du Bing,Zhang Jun school of Electronics and information Engineering,{2. university of Aeronautics and Astronautics,{2. 100191,China [a] school of Electronics information Engineering Beijing University of Aeronautics Astronautics Beijing 100191 China

In this article, we exploit the idea of network-coded cooperative protocol in aeronautical communications which combines different source nodes＇ information at the relay and joint decoding at the destination. Recently, the network coding in cooperative communications has been categorized into two mainstreams, bit-level and signal-level combinations, which are both discussed in the article. And to be exclusively,multiple access relay channel（MARC） is adopted. The mutual information expressions of both above-cited network-coded protocols are deduced, which prove that without proper selected relays to perform network coding, the spatial diversity of the proposed protocol cannot be obtained. This then leads to search for the selection and grouping algorithms. An adjacency matrix is defined to describe the connectivity of the nodes in one radio contact disk, so that, the selection and grouping of algorithm is equivalent to constructing this adjacency matrix to minimize the system outage probability evaluated in term of the mutual information. Besides, a network-coded cooperative protocol requires the acyclic network, of which the construction is to avoid loop-4.in the matrix. The article ends with simulations to demonstrate the viability of the proposed algorithms.

关键词： communication network coding outage probability mutual information bit-level signal-level

Study of Product Quality information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept

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厦门大学学报（自然科学版） 2002年第S1期41卷 234-235页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2. YU Xin-qi 2. RUAN Xin 3 (1. Ordance Institute of General Equipment Department, Shijiazhuang 05 0000, China 2. Graduate school of Chinese Academic of Science, beijing 1000{2., China 3. East China {2. of Science and Technology, Shanghai 2.02.2. China {2. Meterology Bureau of Hebei Province, Shijiazhuang 05002., China)

The 2.th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of China and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:*** type of qua

关键词： product guality information decision-making sup port system of management of guality information people’s guality concept

Prediction of petroleum exploration risk and subterranean spatial distribution of hydrocarbon accumulations

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Petroleum Science 2011年第1期8卷 17-23页

作者： Xie Hongbing Guo Qiulin Li Feng Li Jianzhong Wu Na Hu Suyun Liang Kun school of Energy Resources China University of GeosciencesBeijing 100083China Research Institute of Petroleum exploration ＆ Development PetroChinaBeijing 100083China Science ＆ Technology Management Department China National Petroleum CorporationBeijing 100007China

Investigation of spatial distribution of oil and gas resource and accurate prediction of the geographic location of its undiscovered resource is significant for reducing exploration risk and improving exploration benefit.A new method for predicting spatial distribution of oil resource is discussed in this *** consists of prediction of risk probability in petroleum exploration and simulation of hydrocarbon abundance. exploration risk probability is predicted by multivariate statistics,fuzzy mathematics and {4. processing techniques.A spatial attribute database for sample wells was set up and the Mahalanobis distance and Fuzzy value of given samples were ***,the Bayesian formula was used to calculate the hydrocarbon-bearing probability at the area of exploration ***,a hydrocarbon probability template is formed and used to forecast the probability of the unknown area. The hydrocarbon abundance is simulated based on Fourier integrals,frequency spectrum synthesis and fractal ***,the fast Fourier transformation（FFT） is used to transform the known hydrocarbon abundance from the spatial domain to the frequency domain,then,frequency spectrum synthesis is used to produce the fractal frequency spectrum,and FFT is applied to get the phase {4. of hydrocarbon-bearing ***,the frequency spectrum simulation is used to calculate the renewed hydrocarbon abundance in the play. This method is used to predict the abundance and possible locations of the undiscovered petroleum accumulations in the Nanpu Sag of the Bohai Bay Basin,*** prediction results for the well-explored onshore area of the northern Nanpu Sag agree well with the actual *** the less-explored offshore areas in the southern Nanpu Sag,the prediction results suggest high hydrocarbon abundance in Nanpu-1 and Nanpu-2.providing a useful guiding for future exploration.

关键词： Hydrocarbon resources abundance risk forecast Nanpu sag frequency spectrum simulation fractal theory

Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science China Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2.3, WANG JinDi1,2.& LIANG ShunLin4.1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by beijing Normal {2. and Institute of Remote Sensing Applications, CAS, beijing 100875, China 2.school of Geography, beijing Key Laboratory of Environmental Remote Sensing and Digital City, beijing Normal {2., beijing 100875, China 3 Haihe River Water Conservancy Commission, Tianjin 300170, China 4.Department of Geography, {2. of Maryland, College Park, MD 2.74., USA 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing 100875 China2. School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing 100875 China3. Haihe River Water Conservancy Commission Tianjin 300170 China4. Department of Geography University of Maryland College Park MD 20742 USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of {2., this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

Study on attribute characterization for reservoir dynamic monitoring by seismic

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Science China Earth Sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1,3,LI JingYe2.3 & ZHAO Wei4.1 Key Lab of Geophysical exploration of CNPC,China Petroleum {2.,{2. 102.4.,China 2.Basin & Reservoir Research Center,China Petroleum {2.,{2. 102.4.,China 3 State Key Laboratory of Petroleum Resource and Prospecting,China {2. of Petroleum,{2. 102.4.,China 4.Research Center of CNOOC,{2. 10002.,China 1. Key Lab of Geophysical exploration of CNPC China Petroleum University Beijing 102249 China 3. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Basin & Reservoir Research Center China Petroleum University Beijing 102249 China 4. Research Center of CNOOC Beijing 100027 China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)

Purposeless repeated acquisition time-lapse seismic data processing

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Petroleum Science 2008年第1期5卷 31-36页

作者： Li Jingye Chen Xiaohong Zhao Wei Zhang Yunpeng Key Laboratory for Hydrocarbon Accumulation Mechanism Ministry of Education China University of PetroleumBeijing 102249 China Basin ＆ Reservoir Research Center China University of Petroleum Beijing 102249 China school of Resource and information China University of Petroleum Beijing 102249 China Research Center of CNOOC Beijing 100027 China

In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for searching residual oil in matured fields. Time-lapse seismic reservoir monitoring technique is one of most important techniques to define residual oil distribution. According to the demand for and development of time-lapse seismic reservoir monitoring in China, purposeless repeated acquisition time-lapse seismic data processing was studied. The four key steps in purposeless repeated acquisition time-lapse seismic data processing, including amplitude-preserved processing with relative consistency, rebinning, match filtering and difference calculation, were analyzed by combining theory and real seismic data processing. Meanwhile, quality control during real time-lapse seismic processing was emphasized.

关键词： Time-lapse seismic purposeless repeated acquisition rebinning match filtering amplitude-preserved processing