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New application methods for word-oriented cryptographic primitives

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Science china(information Sciences) 2012年第9期55卷 2149-2160页

作者： YANG Yang 1,2,ZENG Guang 1,2,JIN ChengHui 1 & QU YunYing 1 1 Zhengzhou information Science and Technology Institute,Zhengzhou 450002,china 2 state key laboratory of information security,Institute of Software,Chinese Academy of Sciences,beijing 100190,china 1. Zhengzhou information Science and Technology Institute Zhengzhou 450002 China2. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China

Modern software oriented symmetric ciphers have become a key feature in utilizing word-oriented cryptographic *** the output sequence,in the order of its generation,of a word-oriented cryptographic primitive in the same way as traditional bit-oriented primitives,we can expose the intrinsic weakness of these primitives,especially for word-oriented linear feedback shift registers,T-functions,and so *** new methods for using word-oriented cryptographic primitives are presented in this paper,that is,the extracted state method and cascading extracted coordinate *** a T-function as an example,we research the different cryptographic properties of the output sequences of the original method and the two proposed methods,focusing mainly on period,linear complexity,and k-error linear *** conclusions show that the proposed methods could enhance at low cost the cryptographic properties of the output *** a result,since the new methods are simple and easy to implement,they could be used to design new word-oriented cryptographic primitives.

关键词： stream cipher single cycle T-function linear complexity k-error linear complexity

A tetrahedral data model for unstructured data management

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Science china(information Sciences) 2010年第8期53卷 1497-1510页

作者： LI Wei & LANG Bo state key laboratory of Software Development Environment, Beihang University, beijing 100191, china 1. state key laboratory of Software Development Environment Beihang University Beijing 100191 China

This paper proposes a tetrahedral data model for unstructured data management. The model defines the four components of unstructured data including: basic attributes, semantic characteristics, low-level features and raw data on its four facets, and the relations between these components. The internal implementation structure of the model and the data query language are designed and briefly introduced. This model provides a unified, integrated and associated description for different kinds of unstructured data, and supports intelligent data services such as associated retrieval and data mining. An example is given to demonstrate how to use the model for describing and manipulating data from a sample video base.

关键词： unstructured data data model query language associated retrieval intelligent services

Experimental study of gas-water elongated bubble flow during production logging

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Petroleum Science 2011年第2期8卷 157-162页

作者： Lu Jing Wu Xiling key laboratory of Earth Prospecting and information Technology China University of Petroleum Beijing 102249 China state key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

In order to improve the interpretation of production log data on gas-water elongated bubble （EB） flow in horizontal wells, a multi-phase flow simulation device was set up to conduct a series of measurement experiments using air and tap water as test media, which were measured using a real production logging tool （PLT） string at different deviations and in different mixed flow states. By understanding the characteristics and mechanisms of gas-water EB flow in transparent experimental boreholes during production logging, combined with an analysis of the production log response characteristics and experimental production logging flow pattern maps, a method for flow pattern identification relying on log responses and a drift-flux model were proposed for gas-water EB flow. This model, built upon experimental data of EB flow, reveals physical mechanisms of gas-water EB flow during measurement processing. The coefficients it contains are the specific values under experimental conditions and with the PLT string used in our experiments. These coefficients also reveal the interference with original downhole flow patterns by the PLT string. Due to the representativeness that our simulated flow experiments and PLT string possess, the model coefficients can be applied as empirical values of logging interpretation model parameters directly to real production logging data interpretation, when the measurement circumstances and PLT strings are similar.

关键词： Horizontal wells elongated bubble flow flow patterns identification drift-flux model,logging interpretation model

A prototype auto-human support system for spatial analysis

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Progress in Natural Science:Materials International 2006年第9期16卷 954-966页

作者： LI Lianfa and WANG Jinfeng (state key laboratory of Resources & Environmental information System, Institute of Geographical Sciences & Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china) [a]state key laboratory of Resources & Environmental information System Institute of Geographical Sciences & Natural Resources Research Chinese Academy Sciences Beijing China

Spatial analysis is a multidisciplinary field that involves multiple influential factors, variation and uncertainty, and modeling of geospatial data is a complex procedure affected by spatial context, mechanism and assumptions. In order to make spatial modeling easier, some scholars have suggested a lot of knowledge from exploratory data analysis (EDA), specification of the model, fitness and diagnosis of the model, to interpretation of the model. Also an amount of software has improved some functionalities of spatial analysis, e. g. EDA by the dynamic link (GeoDa) and robust statistical calculation (R). However, there are few programs for spatial analysis that can automatically deal with unstructured declarative issues and uncertainty in machine modeling using the domain knowledge. Under this context, this paper suggests a prototype support system for spatial analysis that can automatically use experience and knowledge from the experts to deal with complexity and uncertainty in modeling. The knowledge base component, as the major contribution of the system, in support of the expert system shell, codes and stores declarative modeling knowledge, e.g. spatial context, mechanisms and prior knowledge to deal with declarative issues during the modeling procedure. With the open architecture, the system integrates functionalities of other components, e.g. GIS’ visualization, DBMS, and robust calculation in an interactive environment. An application case of spatial sampling, design and implementation of spatial modeling with such a system is demonstrated.

关键词： spatial analysis automatic support system modeling of spatial data artificial inference for modeling.

Novel encryption model for multimedia data

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1081-1085页

作者： Ye Dengpan~(1,2) & Lian Shiguo~3 1.The key laboratory of Aerospace information security and Trust Computing,Ministry of Education,Wuhan 430072,P.R.china 2.School of Computer Science,Wuhan Univ.,Wuhan 430072,P.R.china 3.France Telecom R&D beijing,beijing 100080,P.R.china The key laboratory of Aerospace information security and Trust Computing Ministry of Education Wuhan 430072 P. R. China School of Computer Science Wuhan Univ. Wuhan 430072 P. R. China France Telecom R&D beijing Beijing 100080 P. R. China

A novel encryption model is proposed. It combines encryption process with compression process, and realizes compression and encryption at the same time. The model＇s feasibility and security are analyzed in detail. An... 详细信息

关键词： multimedia encryption model compression feasibility security.

Simulation of dam breach development for emergency treatment of the Tangjiashan Quake Lake in china

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Science china(Technological Sciences) 2008年第S2期51卷 82-94页

作者： WANG GuangQian,LIU Fan,FU XuDong & LI TieJian state key laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084,china state key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

The Tangjiashan Quake Lake is the largest quake lake triggered by the 5.12 Wenchuan Earthquake that happened on May 12,2008 in china,posing high risk of catastrophic flash flood hazards to downstream human life and properties.A physics-based numerical simulation approach is proposed for real-time prediction of dam breach development of the Tangjiashan Quake Lake in the case of emergency *** erosion and lateral development of the dam breach are represented through accounting for the underlying physics including selective sediment transport and gravitational *** breach erosion model that involves few parameters enables quick calibration based on the monitored hydrological data in emergency analysis where fully geotechnical information about the barrier dam is not *** process of dam breach development is found to be nonlinear in cascades due to the combined effects of headcutting and bank *** agreement between the simulation results and the observed data shows the applicability of the present approach for emergency analysis of quake *** will arise in the situation where the soil composition of barrier dam is significantly *** of circular arc failure for cohesive soil and lateral seepage in bank slope will also enhance its applicability to complex situations.

关键词： quake lake earthquake dam breach simulation numerical model erosion collapse headcutting

The C-topology on lattice-ordered groups

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Science china Mathematics 2009年第11期52卷 2397-2403页

作者： YANG YiChuan Department of Mathematics,key laboratory of Ministry of Education for information Mathematics and Behavior,Beihang University,beijing,100191 china 1. Department of Mathematics Key Laboratory of Ministry of Education for Information Mathematics and Behavior Beihang University 100191 Beijing China

Let A be a lattice-ordered group. Gusi? showed that A can be equipped with a C-topology which makes A into a topological group. We give a generalization of Gusi?’s theorem, and reveal the very nature of a “C-group” of Gusi? in this paper. Moreover, we show that the C-topological groups are topological lattice-ordered groups, and prove that every archimedean lattice-ordered vector space is a T 2 topological lattice-ordered vector space under the C-topology. An easy example shows that a C-group need not be T 2. A further example demonstrates that a T 2 topological archimedean lattice-ordered group need not be C-archimedean, either.

关键词： C-topology lattice-ordered group archimedean lattice-ordered group Hausdorff topology vector space 06F30 22A99

Research on the Earth system multi-body force system dynamical model

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Science china(Technological Sciences) 2006年第z2期49卷 11-22页

作者： CHEN Xiaofei, BI Siwen, WU Fei & DONG Qianlin state key laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, china laboratory of 3D information Access and Application of Capital Normal University, beijing 100037, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ Beijing 100101 Peoples R China Capital Normal Univ Lab D Informat Access & Applicat 3 Beijing 100037 Peoples R China

This paper presents an overview of the binding force and freedom force of Earth system, and describes force moment to point and line and force system in the Earth system. It introduces the force theory of the Earth system multi-body force system from special or equivalent force system of Earth system mechanics, general force and no-power force of Earth system. Finally it describes the force and moment of nodes of Earth system and provides basic model for the research of the Earth system multi-body dynamics.

关键词： Earth system, multi-body system force, dynamics, basic models.

A new approach toward object-based change detection

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Science china(Technological Sciences) 2010年第S1期53卷 105-110页

作者： ZHANG Guo1,2,LI Yang1 & LI ZhiJiang3 1 state key laboratory of information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,china 2 Satellite of Surveying and Mapping Application center,state Bureau of Surveying and Mapping,beijing 100830,china 3 School of Printing and Packaging,Wuhan University,Wuhan 430079,china Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China state Bur Surveying & Mapping Satellite Surveying & Mapping Applicat Ctr Beijing 100830 Peoples R China Wuhan Univ Sch Printing & Packaging Wuhan 430079 Peoples R China

Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is *** two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding *** change detection is implemented based on the integration of corresponding objects’ intensity and texture *** are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and *** color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral *** verification work is carried out to show the accuracy of the proposed approach.

关键词： mean shift united segmentation change detection object-based intensity texture integration