UBOM:一个基于UML的本体建模工具

企业应用集成和跨企业的应用集成是当前企业信息系统面临的主要挑战,不同应用或系统之间的数据、信息、知识的交换和共享成为研究的焦点.作为概念的规范,本体为领域内人员之间、应用系统之间的通信、信息交换和知识共享提供了一个公共语义平台,是信息集成、应用集成的重要使能技术.DAML+OIL、OWL等基于XML面向WEB的本体描述语言得到了广泛重视,但却存在由于缺乏标准的元建模体系结构而导致语义不清晰等问题,也缺乏必要的可视化建模标准.另一方面,相对成熟的统一建模语言(UML)有明确的模型层次,清晰的语义,已经在软件工程、业务建模等领域得到了广泛使用.本文针对OWL存在的问题,以UML为基础,开发了一个本体建模元模型以及模型元素的可视化表示法,并在开放源代码项目ArgoUML的基础上,实现了一个支持DAML+OIL和OWL的本体建模工具UBOM,支持软件开发人员基于UML开发自有本体库,实现语义使能的应用集成.

Investigation of Quasi-Periodic RF Cavity for High Power Microwave Source

Based on capture, bunching and energy exchange during the interaction between the beam and microwave in the high power microwave device,quasi-periodic RF cavity is proposed in the paper. Electron movement is studied under the action of the microwave field in the RF cavity,and its influence on the microwave field is also investigated.The quasi-periodic RF cavity at Ku-Band is designed by using SUPPERFISH code,and its working frequency is 13.5GHz.In the Simulation(2.5D PIC code),the output power of 2.4GW is obtained at Ku-Band(13.5GHz) using such cavity driven by ring beam,the parameters of the beam are 800kV and 8kA,and the efficiency of the beam momentum into microwave is close to 40%.