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Java实现传统算法加密解密

The Web Service Modeling Ontology (WSMO) is a conceptual model for describing various aspects related to Semantic Web services. The objective of WSMO and its accompanying efforts is to solve the application integration problem for Web services by defining a coherent technology for Semantic Web services. WSMO takes the Web Service Modeling Framework (WSMF) [Fensel & Bussler, 2002] as starting point and further refines and extends its concepts. It is developed by the WSMO working group.

In order to achieve automated discovery, composition, and execution of Web services a conceptual model alone is insufficient. In addition, a formal language is required to write down annotations of Web services according to the conceptual model. Logical inference-mechanisms can be applied to the descriptions in this language. In order to allow appropriate, satisfactorily logic-based reasoning on Semantic Web services, the description language has to provide reasonable expressivity, together with well-defined formal semantics. The Web Services Modeling Language (WSML) is a family of languages which formalizes WSMO. A related goal of WSML is to provide a rule-based language for the Semantic Web. It is developed by the WSML working group, which is a subgroup of the WSMO working group. For a specification of the different WSML variants you can consult [de Bruijn et al., 2005].

Another working group related to WSMO is dedicated to the Web Service Execution Environment (the WSMX working group). The goal of this working group is the development of an execution environment for the dynamic discovery, selection, mediation, invocation and inter-operation of Semantic Web services based on the WSMO specification. WSMX shall provide a reference architecture and implementation for this purpose.

The aim of this primer is to provide an introduction to WSMO and to describe it in sufficient detail to enable the reader to model goals, mediators and Web services. Further, it exemplifies the use and modeling of domain ontologies, which comprise the fourth pillar of WSMO. The target audience are researchers, software engineers and developers, and all other persons interested in and dealing with Semantic Web services. It is the primer's intention to answer questions such as:

What is WSMO in a nutshell? 
How are Semantic Web services modeled using WSMO? 
How is a WSMO component described? 
The primer is based on the work carried on [Roman et al., 2005], which presents the core elements of the Web Service Modeling Ontology and their interrelations. All the examples provided throughout the primer use WSML. It is not the intention of the primer to provide a complete specification of WSMO: further details can be found by in the documents which are listed in Section 6.

The WSMO Primer is organized as follows: Section 2 introduces the basic concepts and model behind WSMO, together with its principles; Section 3 describes the use case that guides the primer; Section 4 provides an overview of the main elements of WSMO. Some conclusions regarding WSMO usability are drawn in Section 5. Finally, Section 6 presents the WSMO specification. The WSML definitions of the entities used for describing the chosen use case, which are spread throughout the whole document in order to exemplify each entity in turn, are gathered as a unified example in a separate Appendix. 

2. Overview
WSMO provides means to describe all relevant aspects of Semantic Web services in a unified manner. Here, we particularly consider all aspects concerning the problems arising in Enterprise Application Integration as relevant. This section describes the approach and basic ideas behind WSMO in order to tackle these problems.

2.1 WSMO Design Principles
WSMO provides ontological specifications for the core elements of Semantic Web services. In fact, Semantic Web services aim at an integrated technology for the next generation of the Web by combining Semantic Web technologies and Web services, thereby turning the Internet from an information repository for human consumption into a world-wide system for distributed Web computing. Therefore, appropriate frameworks for Semantic Web services need to integrate the basic Web design principles, those defined for the Semantic Web, as well as design principles for distributed, service-orientated computing of the Web. WSMO is therefore based on the following design principles:

Web Compliance - WSMO inherits the concept of URI (Universal Resource Identifier) for unique identification of resources as the essential design principle of the Word Wide Web. Moreover, WSMO adopts the concept of Namespaces for denoting consistent information spaces, and supports XMLand other W3C Web technology recommendations, as well as the decentralization of resources. 
Ontology-Based - Ontologies are used as the data model throughout WSMO, meaning that all resource descriptions as well as all data interchanged during service usage are based on ontologies. Ontologies are a widely accepted state-of-the-art knowledge representation, and have thus been identified as the central enabling technology for the Semantic Web. The extensive usage of ontologies allows semantically enhanced information processing as well as support for interoperability; WSMO also supports the ontology languages defined for the Semantic Web. 
Strict Decoupling - Decoupling denotes that WSMO resources are defined in isolation, meaning that each resource is specified independently without regard to possible usage or interactions with other resources. This complies with the open and distributed nature of the Web. 
Centrality of Mediation - As a complementary design principle to strict decoupling, mediation addresses the handling of heterogeneities that naturally arise in open environments. Heterogeneity can occur in terms of data or process. WSMO recognizes the importance of mediation for the successful deployment of Web services by making mediation a first class component of the framework. 
Ontological Role Separation - User requests are formulated independently of (in a different context than) the available Web services. The underlying epistemology of WSMO differentiates between the desires of users or clients and available Web services.
Description versus Implementation - WSMO differentiates between the descriptions of Semantic Web services elements (description) and executable technologies (implementation). While the former requires a concise and sound description framework based on appropriate formalisms in order to provide a concise expression for semantic descriptions, the latter is concerned with the support of existing and emerging execution technologies for the Semantic Web and Web services. WSMO aims at providing an appropriate ontological description model, and to be compliant with existing and emerging technologies. 
Execution Semantics - In order to verify the WSMO specification, the formal execution semantics of reference implementations like WSMX as well as other WSMO-enabled systems provide the technical realization of WSMO. 
Service versus Web service - A Web service is a computational entity which is able (by invocation) to achieve a goal. A service in contrast is the actual value provided by this invocation [Baida et al., 2004], [Preist, 2004]. Thus, WSMO does not specify services, but Web services which are actually means to buy and search services.
2.2 Basic Concepts and Model
WSMO defines the modeling elements for describing several aspects of Semantic Web services based on the conceptual grounding set up in the Web Service Modeling Framework (WSMF) [Fensel and Bussler, 2002], wherein four main components are defined: 

Ontologies: provide the formal semantics to the information used by all other components. 
Goals: specify objectives that a client might have when consulting a Web service. 
Web services: represent the functional (and behavioral) aspects which must be semantically described in order to allow semi-automated use. 
Mediators: used as connectors, they provide interoperability facilities among the other elements. 
WSMO inherits these four top elements, further refining and extending them. Below there is a more detailed description of each of these top-level components of WSMO.

Ontologies represent a key element in WSMO because they provide (domain specific) terminologies for describing the other elements. They serve a twofold purpose: first, defining the formal semantics of the information, and second, linking machine and human terminologies. WSMO specifies the following constituents as part of the description of an ontology: concepts, relations, functions, axioms, and instances of concepts and relations, as well as non-functional properties, imported ontologies, and used mediators. The latter allows the interconnection of different ontologies by using mediators that solve terminology mismatches. A more detailed description of the structure of an ontology together with an example of such a description is given in Section 4.1.