6 resultados para GUIDE-O (Information retrieval system)

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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With the digital all-sky imager (ASI) emergence in aurora research, millions of images are captured annually. However, only a fraction of which can be actually used. To address the problem incurred by low efficient manual processing, an integrated image analysis and retrieval system is developed. For precisely representing aurora image, macroscopic and microscopic features are combined to describe aurora texture. To reduce the feature dimensionality of the huge dataset, a modified local binary pattern (LBP) called ALBP is proposed to depict the microscopic texture, and scale-invariant Gabor and orientation-invariant Gabor are employed to extract the macroscopic texture. A physical property of aurora is inducted as region features to bridge the gap between the low-level visual features and high-level semantic description. The experiments results demonstrate that the ALBP method achieves high classification rate and low computational complexity. The retrieval simulation results show that the developed retrieval system is efficient for huge dataset. (c) 2010 Elsevier Inc. All rights reserved.

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政府信息检索系统作为政府信息公开平台的重要组成部分,对于用户从大量信息中准确查找所需信息起到关键作用,然而现有政府信息检索系统存在两个主要问题:一是系统采用的基于关键词匹配的检索技术忽视了对于用户检索条件的语义的理解,缺乏对于文档实质内涵的准确描述;二是由于对政府信息领域知识的缺乏,用户不能很好地提出符合自己检索需求的检索条件。这两个问题导致检索结果远远不能满足用户的要求。 本体是“概念模型的明确的规范说明”,它提供明确定义的词汇表,描述概念和概念之间的关系,被当作某个领域内不同主体之间进行交流的一种语义基础。它被广泛的应用于信息检索,特别是基于知识的检索中,能显著提高检索系统的查全率和查准率。 本文提出了构建政府信息领域本体并将其应用于政府信息检索系统的方案。首先,研究了现有的领域本体构建方法;在分析了政府信息领域的特点,考察了该领域可用资源的基础上,提出了基于政务主题词表的政府信息领域本体的构建方法。该方法充分利用了《综合电子政务主题词表》中已有的主题词和关系,保证了本体概念添加的完备性和科学性,减少了对领域专家的依赖,提高了构建效率。 设计和实现了基于领域本体的政府信息检索系统。该系统以领域本体为核心,对检索条件进行了扩展,既解决了检索词同政府信息中的公文用词存在差异的问题,又进一步明确了用户的检索需求;对政府信息文档进行了语义标注,提高了检索匹配时的准确度。同时,系统将与检索条件相关的领域概念反馈给用户,便于用户了解领域知识,进一步优化检索条件,获得更全更准的检索结果。

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Through years of practice, reservoir management has already become the basic mode of foreign oil companies to realize the high-efficient development of the oil field. From the view of reservoir development and technological economy, reservoir management regards the study of the reservoir engineering, designs of reservoir projects and the dynamic analysis of the reservoir's performance as a system. In the fields of reservoir description, the establishment of the geological models and development models, the dynamic simulations of reservoir exploitation and the design of the oil engineering, reservoir management emphasizes the cooperation of the geology and the engineering, the combination of the engineering technology and the economic evaluation. In order to provide the means and basis for the reservoir geology study, reservoir evaluation, reserves calculation, numerical simulation, development plan and risk analysis, it adopts the reservoir management activities(team work) to make and implement the optimized oil field development management strategies so that secientific and democratic decision making can be achieved. Under the planned economic system for a long time, the purpose of Chinese reservoir development has been to fulfill the" mandatory" production task. With the deepening of the reform, the management organization of Chinese petroleum enterprises has been gradually going through the transition and reforms to the operational entity and the establishment of the mode of oil companies under the socialist market economy system. This research aims at introducing the advanced reservoir management technique from foreign countries to further improve the reservoir development results and wholly raise the economic benefits of Chinese mature land facieses sandstone reservoirs in the later stage of the water flooding. We are going to set up a set of modern reservoir management modes according to the reservoir features, current situation and existing problems of GangXi oil field of DaGang oil company. Through the study and implementation of the reservoir description and numerical simulation technology effectively, we plan to work out integrated adjustment projects, to study the related technology of oil recovery; to set up the effective confirmable data procedure and data management system of the reservoir management, to establish the coordinated model and workbench related to geology, engineering and economy in order to realize the real time supervision and evaluation on the process of reservoir development. We hope to stipulate modernization management tools for GangXi oil fields to rationally utilize various kinds of existing technological methods and to realize the economic exploitation and achieve the maximum benefits from the reservoir. The project of the modem reservoir management will be carried out on the GangXi oil field of DaGang oil company for this oil field is typical and has integrated foundamental materials and perfect networks. Besides, it is located in the good geographical position enjoying very convenient traffic. Implementing modern reservoir management will raise the recovery ratio, reduce the production cost and improve the working efficiency. Moreover, the popularization of modern reservoir management will improve the comprehensive benefits of DaGang oil company and even the whole Petro China. Through the reserch of this project, the following technical indicators can be reached: Establishing the concept of modern reservoir management. Establishing a set of integrated data information management system adapt to the features of GangXi reservoir. 3. Forming technical research modes of modern reservoir management suitable for mature reservoirs in the later developing stage. 4. Advancing projects of GangXi reservoir which are maxium optimized in engineering technique and economic benefits of oil exploitation. Besides, this set of technology, research principle and method can guide the mature reservoir of DaGang oil field and even the whole PetroChina to develop the further research of reservoir adjustment and improve the reservoir recovery factor and developing level constantly.