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含排他性选择规则的主动规则集的汇流性判定方法 被引量:1
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作者 熊中敏 赵梦露 +1 位作者 周雪楠 黄冬梅 《计算机研究与发展》 EI CSCD 北大核心 2013年第S1期109-116,共8页
主动规则已经应用于主动数据库、XML文档和语义网络等领域,主动规则集的汇流性维护了数据库的数据一致性、保证了数据质量,但现有方法不能有效地判定主动规则集的汇流性.现有的方法基于规则可交换性进行判定,但只是针对指定了优先级的... 主动规则已经应用于主动数据库、XML文档和语义网络等领域,主动规则集的汇流性维护了数据库的数据一致性、保证了数据质量,但现有方法不能有效地判定主动规则集的汇流性.现有的方法基于规则可交换性进行判定,但只是针对指定了优先级的规则集,对没有指定优先级的规则集的汇流性没有相应的判定方法;同时也没有考虑在同一个初始状态下,不同的规则调度是否都能被条件满足.为此,提出了排他性选择规则的概念和更有效的汇流性先决条件及其汇流判定定理.同时给出了新的判定算法的完整描述及其可终止性、正确性证明和复杂度分析. 展开更多
关键词 主动数据库 规则分析 汇流性 排他选择规则 数据质量
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基于条件冲突分析的主动规则集汇流性判定方法
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作者 熊中敏 朱吉光 +1 位作者 李长绩 袁红春 《计算机科学》 CSCD 北大核心 2016年第5期169-173,共5页
主动规则使数据库具备自反应能力,在数据库、知识库和无线传感器网络等领域得到了广泛应用。汇流性分析是保持数据一致性的重要手段,但有效判定汇流性仍是一个难题。现有的方法基于规则可交换性进行判定,没有考虑规则之间是否存在条件... 主动规则使数据库具备自反应能力,在数据库、知识库和无线传感器网络等领域得到了广泛应用。汇流性分析是保持数据一致性的重要手段,但有效判定汇流性仍是一个难题。现有的方法基于规则可交换性进行判定,没有考虑规则之间是否存在条件冲突而导致它们不可能同时出现在同一个执行序列中;同时基于触发关系的集合分析没有考虑在规则触发序列中的先后时序性。为此,提出了规则的触发序列概念,分析了单个触发序列上的条件冲突和一对无序规则所在的两条触发序列之间的条件冲突,从而提出了更有效的汇流性先决条件及其判定定理,同时给出了新的判定算法的完整描述及其可终止性、正确性证明和复杂度分析。 展开更多
关键词 主动数据库 规则分析 汇流性 条件冲突 数据一致
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主动规则的汇流性分析
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作者 杨泽雪 《哈尔滨师范大学自然科学学报》 CAS 2008年第1期65-68,共4页
规则集的汇流是指最终的数据库状态不依赖于主动规则被选择执行的顺序.针对主动规则汇流性分析方法的局限性,介绍一种主动数据库规则汇流性分析的新方法,此方法将主动规则翻译成逻辑语句,考虑到系统的执行语义,转换为演绎规则中已知汇... 规则集的汇流是指最终的数据库状态不依赖于主动规则被选择执行的顺序.针对主动规则汇流性分析方法的局限性,介绍一种主动数据库规则汇流性分析的新方法,此方法将主动规则翻译成逻辑语句,考虑到系统的执行语义,转换为演绎规则中已知汇流性的主动过程. 展开更多
关键词 主动数据库 汇流性 演绎数据库
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关于主动数据库的汇流性问题
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作者 蒋传来 郝忠孝 《哈尔滨理工大学学报》 CAS 2004年第2期73-75,共3页
针对主动数据库主动规则汇流性分析问题,必须考虑规则与规则之间的相互影响,讨论了带有规则交互关系的主动数据库中的汇流性属性,并在分析了规则的交互关系的基础上,给出了保证主动数据库汇流的充分条件。
关键词 主动数据库 汇流性 事件 条件 动作 主动规则
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基于执行图的主动规则集汇流性判定
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作者 刘泓漫 《上海电机学院学报》 2006年第S1期5-7,15,共4页
针对主动规则集的汇流性问题进行了研究,通过对规则的可交换性及执行图的分析,提出了主动规则集汇流性判定定理,该定理的提出提高了汇流性判定的精确度。
关键词 规则集 汇流性 执行图
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Assessment of Diversity, Distribution, Conservation Status and Preparation of Management Plan for Medicinal Plants in the Catchment Area of Parbati Hydroelectric Project Stage-Ⅲ in Northwestern Himalaya 被引量:4
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作者 S.S. Samant Jitendra S. Butola Aman Sharma 《Journal of Mountain Science》 SCIE CSCD 2007年第1期34-56,共23页
The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity in the Indian Himalayan Region. The Himaehal Pradesh, a part of IHR is well known for the ... The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity in the Indian Himalayan Region. The Himaehal Pradesh, a part of IHR is well known for the development of hydroelectric projects. The Parbati H.E. Project is amongst the major projects of the State. The different stages of the project are all causing loss of biodiversity of the area. Stage Ⅲ of the Parbati H.E. Project is a run of the river scheme on the Sainj River downstream of Power House of Parbati H.E. Project Stage Ⅱ. The project shall utilize regulated discharge of Parbati H.E. Project Stage Ⅱ and inflow of River Sainj for power generation, and has been contemplated as a peaking station operating in tandem with Stage Ⅱ. The present study has been undertaken to see the impact of hydroelectric project on the biodiversity, particularly on medicinal plants. A total of 104 species of medicinal plants, belonging to different life forms, i.e., trees (23 spp.), shrubs (22 spp.), herbs (57 spp.) and ferns (2 spp.) were recorded. The species have been analyzed and studied for their distribution, classification, altitudinal zones, part (s) used, indigenous uses, nativity, endemism and rarity.Different parts of these species, such as whole plants, roots (including rhizomes and tubers), leaves, flowers, fruits, seeds, stems, barks, spikes, nuts and insect galls are used by the inhabitants for curing various diseases and ailments. 3o species are native to the Himalayan region, 9 species native to the Himalayan region and adjacent countries also and 65 species are non-natives. 9 species are near endemics. Considering the whole Himalaya as a biogeographie unit (sensu lato), the near endemics are endemic to the Himalaya. Among these species, Zanthoxylum armature is categorized as Endangered and Valeriana wallichii as Vulnerable. Hedychium spicatum, Rhus javanica, Berberis lycium, Thalictrum foliolossum, Salvia lanata, Rubia cordifolia and Bergenia ligulata may be considered as threatened species due to their over exploitation for trade. 90 species are propagated by seeds, 8 species by seeds and rhizomes/roots/tubers, 4 species by seeds and cuttings, and 2 species by sori. A management plan for the cultivation and conservation of the medicinal plants in the dam submergence area, and the commercially viable medicinal plants with high value in the catchment area is suggested. 展开更多
关键词 Hydroelectric project dam submergence area management plan medicinal plant DIVERSITY native endemic ENDANGERED conservation status indigenous uses Indian Himalaya
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LEXICAL RICHNESS IN L2 ACADEMIC WRITING 被引量:2
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作者 汪澜 《Chinese Journal of Applied Linguistics》 2005年第5期18-23,128,共7页
This preliminary study investigates the relationship between lexical richness and communicative effectiveness in placement essays for graduate students whose first language (L1) is Chinese. Lexical richness is measure... This preliminary study investigates the relationship between lexical richness and communicative effectiveness in placement essays for graduate students whose first language (L1) is Chinese. Lexical richness is measured with Nation's web-based vocabulary profiler (Cobb, undated) software, and communicative effectiveness is scored by multiple raters. The structure of the study, lexical data compile review, results analysis, and teaching implications will be discussed. The study indicates that lexical richness needs to be taken into account in scoring the quality of writing. However, further investigation and analysis still need to be developed and discussed on the ongoing study. 展开更多
关键词 lexical richness communicative effectiveness L2 academic writing type/token ratio essay score corpus linguistics
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Convective Assembly of Linear Gold Nanoparticle Arrays at the Micron Scale for Surface Enhanced Raman Scattering 被引量:8
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作者 Lihua Qian Ronobir Mookherjee 《Nano Research》 SCIE EI CAS CSCD 2011年第11期1117-1128,共12页
A convective assembly technique at the micron scale analogous to the writing action of a "pipette pen" has been developed for the linear assembly of gold nanoparticle strips with micron scale width and millimeter sc... A convective assembly technique at the micron scale analogous to the writing action of a "pipette pen" has been developed for the linear assembly of gold nanoparticle strips with micron scale width and millimeter scale length for surface enhanced Raman scattering (SERS). The arrays with interparticle gaps smaller than 3 nm are hexagonally stacked in the vicinity of the pipette tip. Variable numbers of stacked layers and clean surfaces of the assembled nanoparticles are obtained by optimizing the velocity of the pipette tip. The SERS properties of tile assembled nanoparticle arrays rely on their stacking number and surface cleanliness. 展开更多
关键词 Convective assembly gold nanoparticle surface enhanced Raman scattering pipette writing
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