基于Internet的土地利用管理信息系统关键技术研究

在土地部门实现土地信息共享是土地利用管理信息系统的必由之路,讨论了建立基于Internet的土地利用管理信息系统所要解决的关键技术,包括异构数据的连接,土地信息的互操作和数据的安全控制,其中异构数据的连接是实现信息共享的基础,同时也是土地信息互操作的前提,另外,数据的安全控制对土地利用管理信息系统的建立同样是至关重要的。     

基于CORBA的WebGIS研究

WebGIS蓬勃发展使得通过网络获取空间信息成为可能。然而．地理数据有异构性的特点．这种异构性限制了用户对远程数据的获取。本文基于公共对象请求代理体系结构(CORBA)对WebGIS的通用框架进行探讨．以实现对异构数据的获取与互操作。     

基于Agent的分布式数据库异构消解策略

目前分布式数据库的使用是非常广泛的,但是由于实际情况的需要,不同的站点使用的本地数据库系统可能是不同的,这就出现了异地、异构数据库系统之间的互操作问题。根据多数据库系统各种异构类型和它的应用特点,本文提出了使用Agent技术来解决分布式系统中异构数据库的互操作问题。     

分布式数据库异构消解研究

在Web平台上进行不同的数据库管理系统集成时,首先面临的问题是异地、异构数据库系统间的互操作问题。根据多数据库系统各种异构类型和它的应用特点,文章提出了建立基于CORBA机制和XML文档为公共数据模式的大型分布式数据库系统解决各LDB间的互操作问题,并且对系统的框架结构进行了设计和分析。     

基于CORBA／Web技术的企业级信息系统集成

以制造企业产品远程协同设计制造为背景，基于分布式对象CORBA集成平台，在分布式异构网络环境下，研究基于Web的企业信息系统分布式应用互操作层次体系结构、异构信息数据资源及应用系统与Internet／Intranet的无缝接入方法。针对异地信息资源的远程访问与应用互操作的实现模型、实现方法与支撑机制进行论述，提出了企业级信息系统集成的分布式应用互操作体系结构模型与实现模型。     

普适计算环境中异构资源互操作的代数方法研究

分析了普适计算对异构资源互操作和集成的需求,以及目前异构资源互操作、集成技术中存在的问题。针对异构信息源互操作技术存在的语义层的问题,提出了一种本体代数方法,建立了一套较完整的本体代数理论体系。本研究完善和发展了已有的本体代数理论,为普适计算环境异构数据的集成和互操作、异构本体资源的管理、查询等提供了理论基础。     

政务网络信息系统的异构分布式数据库研究

在当前政务网络信息系统中，多个部门系统数据库之间存在明显的异构性、独立性和自主性，使不同部门之间的信息交流成为难题。采用局部数据集成技术在网络信息中心构建互连通讯平台，开发部门子系统进行数据查询、接收、核对、确认等方法，能够实现政务网络信息系统异构分布式数据库之间的信息共享。     

拟态防御DHR模型若干问题探讨和性能评估

针对传统防御技术难以应对未知特征和未知缺陷的攻击,近年来,工业界和学术界尝试发展能够“改变游戏规则”的创新性防御技术。网络空间拟态防御（CMD：Cyberspace Mimic Defense）以动态异构冗余（DHR：Dynamical Heterogeneous Redundant）作为核心架构技术。针对信息系统保护的元功能,采用非相似余度设计方法构造多个功能等价的异构执行体;在系统运行期间,动态调度元功能的不同异构执行体在线运行,以阻断攻击者的攻击过程;同时,利用多模判决机制对多个异构执行体的输出结果进行判决,以检测是否发生攻击。本文针对DHR模型的若干问题进行了探讨,给出了一种理论分析方法,并进行了实验仿真,理论分析和仿真结果表明,DHR能够大幅提升攻击者攻击难度,增强信息系统的安全性。     

C3I异构型数据库通信平台实现技术

本文主要论述了异构型数据库通信平台课题的设计思想与实现技术,该课题主要是针对异构型数据库集成与互操作问题而研制的。最终在异构网络环境下为用户提供了一个界面友好、操作方便灵活,集数据转储、数据操作为一体的集成化平台。     

基于CORBA／XML的多数据库系统的研究与实现

多数据库系统是实现多个分布的异构数据源数据共享和互操作的有效途径。首先介绍了一种基于CORBA的多数据库系统体系结构模型，然后提出了一种面向XML的公共数据模型XIDM，这些模型能很好适应多数据库系统分布性，自治性和异构性等特点，还对基于这些模型所实现的一个多数据库原型系统Panorama进行了介绍。     

语义信息集成中格式异构解决方案

基于本体的语义信息集成能够解决分布环境下异构数据源之间的模式异构,而对于广泛存在的上下文异构却无法解决。由于上下文异构是暗含的语义,无法为信息系统俘获和理解,要解决上下文异构,必须将上下文语义进行形式化描述。本文首先提出了一种将暗含的上下文语义进行形式化描述的方法,然后在此基础上提出了一种基于元数据格式表示的上下文转换方法来解决上下文异构中的格式异构。该方法避免了已有转换方法需要反复定义大量映射的缺点,提高了上下文转换的灵活性、适应性和扩展性。     

A hybrid ontology approach for integration of obsolescence information

Information sharing among distributed obsolescence management systems is a challenge because of the heterogeneity of data (data with different forms and representations). Indeed, this is the main hurdle that exists for current tools managing product obsolescence. This paper presents a hybrid ontology approach for the integration of obsolescence information that combines a global ontology that provides a shared vocabulary for the specification of the semantics of obsolescence domain knowledge, along with local ontologies that describe structures of multiple data sources distributed in various obsolescence management tools. A procedure is provided for mapping local ontologies to the global ontology by quantifying relationships between classes and identifying groups of classes with a clustering method. Ontologies and rules of identifying relationships are realized with OWL (Web Ontology Language) and SWRL (Semantic Web Rule Language). With the application of the hybrid ontology approach, a unified view of data is provided to support decision making for efficient obsolescence management and a structure where new sources of information can be easily added with little modification in the future.     

面向拟态防御系统的高阶异构度大数判决算法

异构系统之间的相似性会影响拟态防御系统异构执行体的选择和调度。目前多数针对执行体的异构性分析仍停留在二阶层面,但二阶异构度不适用于执行体数目较多的情况,难以准确评估拟态系统的防御能力。针对该问题,提出高阶异构度的概念,分析高阶异构的性质,解释高阶异构性在执行体调度及判决中所起的重要作用,并将其用于拟态防御系统安全性的量化分析。在此基础上,设计基于高阶异构度的大数判决算法,同时依据容斥原理计算系统失效率。实验结果表明,该算法可有效分析拟态系统的防御能力,并且随着执行体相似度增大以及执行体数目增多,准确性能够进一步提高。     

组合粗尺度异质性和细尺度匀质性的像元交换算法用于超分辨率制图

空间依赖性的刻画对超分辨率制图方法起着关键作用。根据观察及实验,粗尺度空间能更好地刻画空间地物异质性,同时细尺度空间能更好地刻画空间地物的匀质性。因此提出了一种结合粗尺度空间异质性和细尺度空间匀质性的像元交换算法用于超分辨率制图。提出的基于组合粗尺度异质性和细尺度匀质性的空间依赖性度量能更好地刻画复杂地物环境。在合成影像上的实验结果验证了提出的算法能在保持分数信息不变的前提下获得更高的制图精度。     

Integration of Heterogeneity for Human-Friendly Robotic Operations

The objective of this paper is to develop an analytical scheme to integrate the heterogeneity of human and robot functions to achieve a human-friendly robotic operations. The heterogeneity of human and robot functions can be characterized by the fact that humans are intelligent while robots are fast, powerful and accurate. Humans can use their knowledge and experience to quickly respond to unexpected events, which makes it easy for humans to deal with unstructured environments. In contrast, robots can easily enhance the mechanical power of humans and the ability of humans to work remotely. Therefore, robots are capable of performing precise and repetitive tasks at high speed or in a hazardous environment. The important issue, in light of human/robot heterogeneity, is how to plan and control a robotic operation such that the human and the robot can cooperate in a complementary manner. Thus, a task which cannot be done by either human or robot alone can be performed efficiently and robustly by both. This paper introduces a new paradigm for human/robot interactive systems, heterogeneous function-based human/robot cooperation. A new perceptive action reference frame has been developed in the paper. It matches human perception and robot sensory measurement, and provides a platform for modeling the human/robot cooperative operations. The theoretical results presented in the paper have laid down a foundation for stability analysis as well as a planning and control system design of human/robot integrated systems. The implementations and experimental results have clearly demonstrated the advantages of proposed methods.     

Performance modeling and analysis of heterogeneous meta-computing systems interconnection networks

The overall performance of a distributed system often depends on the effectiveness of its interconnection network. Thus, the study of the communication networks for distributed systems is very important, which is the focus of this paper. In particular, we address the problem of interconnection networks performance modeling for heterogeneous meta-computing systems. We consider the meta-computing system as a typical multi-cluster system. Since the heterogeneity is becoming common in such systems, we take into account network as well as cluster size heterogeneity to propose the model. To this end, we present an analytical network model and validate the model through comprehensive simulation. The results of the simulation demonstrated that the proposed model exhibits a good degree of accuracy for various system organizations and under different working conditions.     

Incidental exposure to news: Predictors in the social media setting and effects on information gain online

Employing two studies, this paper investigates incidental exposure to news online in terms of its influence on individual learning about public affairs as well as its predictors in the social media environment. Study 1, using an experimental design, shows that incidental exposure to news has significant effects on an individual's recognition and recall of information in news stories. The effects of incidental exposure on recall are mediated by actual exposure to information in the news (spending some time on reading), suggesting gateway effects of initial exposure by accident. Employing a national survey, Study 2 finds that social media network heterogeneity and proportion of weak ties are positively associated with likelihood of incidental exposure to news online, while most variables of individual characteristics are not. The significant effects of structural factors found suggest that incidental exposure can limit consequences of selective exposure. Further implications of the findings are discussed.     

A simple system for constructing distributed,mixed-language programs

The Mixed-Language Programming (MLP) System is a simple system that facilitates construction of sequential programs in which procedures can be written in different programming languages to exploit heterogeneity in language functionality. In addition, MLP provides a simple remote procedure call (RPC) facility that allows heterogeneity in machine functionality to be exploited. To minimize implementation cost, the system does not solve all of the problems related to mixed-language programming; rather, MLP is designed to handle common situations well. Among the unique aspects of MLP are its advanced facilities, which allow complex situations to be handled with user intervention; for example, these facilities allow arguments of a type not defined by a language to be used by procedures written in that language. This paper overviews the use of MLP and describes its implementation. In addition, two programs that have been written using the MLP system—a small database system and a collection of plot routines—are discussed. The system executes on a collection of Vaxes and Suns running Berkeley UNIX. Currently supported languages are C, Pascal and Icon.