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Semantic Complex Event Detection System of Express Delivery Business with Data Support From Multidimensional Space
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《International English Education Research》 2013年第12期197-200,共4页
The express delivery induslry of China is relatively backward in the automation degree of critical business processes. The basic reason is that the business-related supporting data, which is scattered in the multidime... The express delivery induslry of China is relatively backward in the automation degree of critical business processes. The basic reason is that the business-related supporting data, which is scattered in the multidimensional space, is difficult to utilize and process. This paper proposes an automatic data acquisition fi-amework to resolve such difficulty, which synthetically utilize intelligent inemet of things (IoT), semantic web and complext event processing (CEP) technology. We also implement a SCEP prototype system with the capability of real-time detecting complex business events on the goods sorting line, which adopts a detection method consisting of four stages. The simulation results show that the system has good performance and feasible enough to deal with the complex business which need data support fTom multidimensional space. 展开更多
关键词 interact of things semantic web complex event processing express delivery industry domain ontology detection method
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RFID Complex Event Processing: Applications in Real-Time Locating System 被引量:2
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作者 Yao-zong Liu Hong Zhang Yong-li Wang 《International Journal of Intelligence Science》 2012年第4期160-165,共6页
Complex event processing (CEP) can extract meaningful events for real-time locating system (RTLS) applications. To identify complex event accurately in RTLS, we propose a new RFID complex event processing method GEEP,... Complex event processing (CEP) can extract meaningful events for real-time locating system (RTLS) applications. To identify complex event accurately in RTLS, we propose a new RFID complex event processing method GEEP, which is based on the timed automata (TA) theory. By devising RFID locating application into complex events, we model the timing diagram of RFID data streams based on the TA. We optimize the constraint of the event streams and propose a novel method to derive the constraint between objects, as well as the constraint between object and location. Experiments prove the proposed method reduces the cost of RFID complex event processing, and improves the efficiency of the RTLS. 展开更多
关键词 complex event Processing (CEP) REAL-TIME Locating System (RTLS) Radio Frequency Identification (RFID) TIMED AUTOMATA (TA) event-Clock AUTOMATA (ECA)
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Optimization Techniques for RFID Complex Event Processing 被引量:4
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作者 刘海龙 陈群 李战怀 《Journal of Computer Science & Technology》 SCIE EI CSCD 2009年第4期723-733,共11页
One research crucial to wider adoption of Radio Frequency Identification (RFID) technology is how to efficiently transform sequences of RFID readings into meaningful business events. Contrary to traditional events, ... One research crucial to wider adoption of Radio Frequency Identification (RFID) technology is how to efficiently transform sequences of RFID readings into meaningful business events. Contrary to traditional events, RFID readings are usually of high volume and velocity, and have the attributes representing their reading objects, occurrence times and spots. Based on these characteristics and the Non-deterministic Finite Automata (NFA) implementation framework, this paper studies the performance issues of RFID complex event processing and proposes corresponding optimization techniques. Our techniques include: (1) taking advantage of negation events or exclusiveness between events to prune intermediate results, thus reduces memory consumption; (2) with different selectivities of complex events, purposefully reordering the join operations between events to improve overall efficiency, achieve higher stream throughput; (3) utilizing the slot-based or B+-tree-based approach to optimizing the processing performance with the time window constraint. We present the analytical results of these techniques and validate their effectiveness through experiments. 展开更多
关键词 computer science RFID complex event processing THROUGHPUT memory consumption
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An efficient complex event detection model for high proportion disordered RFID event stream 被引量:1
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作者 Jianhua Wang Jun liu +1 位作者 Tao Wang Lianglun Cheng 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2017年第4期175-189,共15页
With the aim of solving the detection problems for current complex event detection models in detecting a related event for a complex event from the high proportion disordered RFID event stream due to its big uncertain... With the aim of solving the detection problems for current complex event detection models in detecting a related event for a complex event from the high proportion disordered RFID event stream due to its big uncertainty arrival,an efficient complex event detection model based on Extended Nondeterministic Finite Automaton(ENFA)is proposed in this paper.The achievement of the paper rests on the fact that an efficient complex event detection model based on ENFA is presented to successfully realize the detection of a related event for a complex event from the high proportion disordered RFID event stream.Specially,in our model,we successfully use a new ENFA-based complex event detection model instead of an NFA-based complex event detection model to realize the detection of the related events for a complex event from the high proportion disordered RFID event stream by expanding the traditional NFA-based detection model,which can effectively address the problems above.The experimental results show that the proposed model in this paper outperforms some general models in saving detection time,memory consumption,detection latency and improving detection throughput for detecting a related event of a complex event from the high proportion out-of-order RFID event stream. 展开更多
关键词 complex event detection model high proportion disorder event stream ENFA
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Aggressive Complex Event Processing with Confidence over Out-of-Order Streams
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作者 李传文 谷峪 +1 位作者 于戈 Bonghee Hong 《Journal of Computer Science & Technology》 SCIE EI CSCD 2011年第4期685-696,共12页
In recent years, there has been a growing need for complex event processing (CEP), ranging from supply chain management to security monitoring. In many scenarios events are generated in different sources but arrive ... In recent years, there has been a growing need for complex event processing (CEP), ranging from supply chain management to security monitoring. In many scenarios events are generated in different sources but arrive at the central server out of order, due to the differences of network latencies. Most state-of-the-art techniques process out-of-order events by buffering the events until the total event order within a specified range can be guaranteed. Their main problems are leading to increasing response time and reducing system throughput. This paper aims to build a high performance out-of- order event processing mechanism, which can match events as soon as they arrive instead of buffering them till all arrive. A suffix-automaton-based event matching algorithm is proposed to speed up query processing, and a confidence-based accuracy evaluation is proposed to control the query result quality. The performance of our approach is evaluated through detailed accuracy and response time analysis. As experimental results show, our approach can obviously speed up the query matching time and produce reasonable query results. 展开更多
关键词 complex event processing (CEP) out-of-order suffix-automaton searching-table
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A multiple-pattern complex event matching model based on merge sharing for massive event streams
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作者 Jianhua Wang Junhe Liu +3 位作者 Feng Lin Jing Zhao Yongbing Long Yubin Lan 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2021年第4期140-155,共16页
Quickly matching the related primitive events for multiple complex events from the massive event streams usually faces with a great challenge due to the single-pattern characteristics of the existing complex event m... Quickly matching the related primitive events for multiple complex events from the massive event streams usually faces with a great challenge due to the single-pattern characteristics of the existing complex event matching models. Aiming to solve the problem, amultiple-pattern complex event matching model based on merge sharing is proposed inthis paper. The achievement of the paper lies in the fact that a multiple-pattern complexevent matching model based on merge sharing is presented to successfully realize thequick matching of related primitive events for multiple complex events from the massiveevent streams. Specifically, in our scheme, we successfully use merge sharing technologyto merge all the same prefixes, suffixes or subpatterns existing in single-pattern matchingmodels into shared ones and to construct a multiple-pattern complex event matchingmodel. As a result, our proposed matching model in this paper can effectively solve theabove problem. The experimental results show that our proposed matching model in thispaper outperforms the existing single-pattern matching models in model constructionand related events matching for massive event streams. 展开更多
关键词 complex event matching model merge sharing massive event streams
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Optimization RFID-enabled Retail Store Management with Complex Event Processing 被引量:1
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作者 Shang-Lian Peng Ci-Jian Liu +2 位作者 Jia He Hong-Nian Yu Fan Li 《International Journal of Automation and computing》 EI CSCD 2019年第1期52-64,共13页
Radio frequency identification(RFID) enabled retail store management needs workflow optimization to facilitate real-time decision making. In this paper, complex event processing(CEP) based RFID-enabled retail store ma... Radio frequency identification(RFID) enabled retail store management needs workflow optimization to facilitate real-time decision making. In this paper, complex event processing(CEP) based RFID-enabled retail store management is studied, particularly focusing on automated shelf replenishment decisions. We define different types of event queries to describe retailer store workflow action over the RFID data streams on multiple tagging levels(e.g., item level and container level). Non-deterministic finite automata(NFA)based evaluation models are used to detect event patterns. To manage pattern match results in the process of event detection, optimization algorithm is applied in the event model to share event detection results. A simulated RFID-enabled retail store is used to verify the effectiveness of the method, experiment results show that the algorithm is effective and could optimize retail store management workflow. 展开更多
关键词 complex event processing(CEP) radio frequency identification(RFID) Internet of THINGS data STREAM supply CHAIN RETAIL STORE
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Synchronization of Markovian jumping complex networks with event-triggered control 被引量:1
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作者 邵浩宇 胡爱花 刘丹 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期595-602,共8页
This paper investigates event-triggered synchronization for complex networks with Markovian jumping parameters.Nonlinear dynamics with Markovian jumping parameters is considered for each node in a complex network. By ... This paper investigates event-triggered synchronization for complex networks with Markovian jumping parameters.Nonlinear dynamics with Markovian jumping parameters is considered for each node in a complex network. By utilizing the proposed event-triggered strategy, and based on the Lyapunov functional method and linear matrix inequality technology,some sufficient conditions for synchronization of complex networks are derived whether the transition rate matrix for the Markov process is completely known or not. Finally, a numerical example is presented to illustrate the effectiveness of the proposed theoretical results. 展开更多
关键词 complex networks SYNCHRONIZATION event-triggered control Markovian jumping parameters
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Classification of Complex Reservoirs in Superimposed Basins of Western China 被引量:11
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作者 PANG Xiongqi ZHOU Xinyuan +3 位作者 LIN Changsong HUO Zhipeng LUO Xiaorong PANG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1011-1034,共24页
Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed b... Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins. The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation, stratigraphic structure and stratigraphic stress-strain action over geological history. Based on the correlation of chronological age on structural sections, superimposed basins can be divided into five types in this study: (1) continuous sedimentation type superimposed basins, (2) middle and late stratigraphic superimposed basins, (3) early and late stratigraphic superimposed basins, (4) early and middle stratigraphic superimposed basins, and (5) long-term exposed superimposed basins. Multiple source-reservoir-caprock assemblages have developed in such basins. In addition, multi-stage hydrocarbon generation and expulsion, multiple sources, polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment, reformation and destruction have occurred in these basins. The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs, and the root causes of this are folding, denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage, diffusion, spilling, oxidation, degradation and cracking. Based on their genesis characteristics, complex reservoirs are divided into five categories: (1) primary reservoirs, (2) trap adjustment type reservoirs, (3) component variant reservoirs, (4) phase conversion type reservoirs and (5) scale-reformed reservoirs. 展开更多
关键词 complex reservoirs tectonic event physically destructive effect chemically destructiveeffect western China's superimposed basins
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海南岛抱板杂岩记录的多期构造热事件:锆石和独居石U-Pb年代学的制约 被引量:2
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作者 陈龙耀 刘晓春 +2 位作者 胡娟 夏蒙蒙 韩建恩 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第1期119-139,共21页
抱板杂岩(抱板群)是海南岛目前已发现的最古老前寒武纪结晶基底,记录了多期构造热事件,是研究海南岛大地构造属性的重要窗口。本文通过对海南岛冲卒岭地区抱板杂岩变质沉积岩、变质基性岩和伟晶岩脉的锆石和独居石LA-ICP-MS U-Pb年代学... 抱板杂岩(抱板群)是海南岛目前已发现的最古老前寒武纪结晶基底,记录了多期构造热事件,是研究海南岛大地构造属性的重要窗口。本文通过对海南岛冲卒岭地区抱板杂岩变质沉积岩、变质基性岩和伟晶岩脉的锆石和独居石LA-ICP-MS U-Pb年代学研究,来确定抱板杂岩所经历的多期构造热事件及其所代表的构造意义。研究结果显示,抱板杂岩主要由中元古代变质沉积岩、花岗质片麻岩和变质基性岩组成,经历了中元古代晚期-新元古代早期(1.3~0.9Ga)、早古生代(470~440Ma)、三叠纪(~230Ma)等多期构造热事件的改造。中元古代晚期-新元古代早期构造热事件与罗迪尼亚超大陆的汇聚有关;早古生代构造热事件与东冈瓦纳古陆北缘的增生造山作用有关;三叠纪构造热事件是印支陆块与华南陆块碰撞拼合的远程响应。综合上述研究成果和区域对比分析,认为海南岛与印支陆块具有相似的前寒武纪结晶基底和多期构造热事件的记录,表明二者具有明显的亲缘关系。 展开更多
关键词 锆石和独居石U-Pb年龄 构造热事件 构造属性 抱板杂岩 海南岛
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清代诗歌的复杂性生成背景与可能性研究进路 被引量:3
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作者 罗时进 《苏州大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第2期150-159,共10页
清诗是在清代社会历史的土壤上生成的,历史的复杂性决定了诗人情感世界的复杂,诗思书写的复杂。作为一种“复杂关系”中的个体,清代诗人们的创作由身世而及民生,由家国而及社会,由种教而及民族,内容极为丰富,且作品数量庞大。在中国古... 清诗是在清代社会历史的土壤上生成的,历史的复杂性决定了诗人情感世界的复杂,诗思书写的复杂。作为一种“复杂关系”中的个体,清代诗人们的创作由身世而及民生,由家国而及社会,由种教而及民族,内容极为丰富,且作品数量庞大。在中国古代诗史的最后一个阶段,往代诗歌发展的每一个知识板块都由川流而成江河,造就出一个规模巨大的诗歌王国。这个诗歌王国至今尚存在很多未知因素,有很多需要探索、垦拓的领域。在现有条件下开展清诗研究,应重视清代诗人天下观、国家观、民族观的变化,于新的文化理念中展开古今通变的思考,并注意对应具体现象和问题,去采取有效方法,寻求可能进路。 展开更多
关键词 清代诗歌 复杂性背景 价值认识 事件叙述 研究进路
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一种面向项目管理信息系统集成的复杂事件处理方法
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作者 李青 王东 +1 位作者 王卓昊 张志刚 《计算机应用与软件》 北大核心 2024年第9期391-397,共7页
大型项目管理信息系统中实时产生的海量事件,对深度挖掘系统的隐含特征具有重要意义。通过分析科技计划项目管理的业务逻辑和事件结构,提出项目管理事件模型。为描述事件之间的关系,定义项目管理事件操作符,实现事件的逻辑、算数和时间... 大型项目管理信息系统中实时产生的海量事件,对深度挖掘系统的隐含特征具有重要意义。通过分析科技计划项目管理的业务逻辑和事件结构,提出项目管理事件模型。为描述事件之间的关系,定义项目管理事件操作符,实现事件的逻辑、算数和时间计算。基于复杂事件处理技术,提出一种面向项目管理信息系统的事件处理算法PMEP,执行事件处理规则,分析系统产生的海量事件,得到深层次的项目管理复杂事件。实验表明,PMEP算法可实现项目管理信息系统中海量事件的实时处理。 展开更多
关键词 复杂事件处理 科技管理业务模型 事件处理算法 科技项目管理信息系统
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空管数据复杂事件处理技术研究
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作者 张志远 李博宇 《计算机应用与软件》 北大核心 2024年第11期153-159,187,共8页
为智能化处理空中交通数据所蕴含的复杂态势,依据空管领域特性,在复杂事件处理技术的基础上设计实现一个空管复杂事件处理系统,进行数据处理与Web可视化;参考民航业规章及专业知识,制定飞机安全间隔预警、飞机高度变化异常、飞机遭遇恶... 为智能化处理空中交通数据所蕴含的复杂态势,依据空管领域特性,在复杂事件处理技术的基础上设计实现一个空管复杂事件处理系统,进行数据处理与Web可视化;参考民航业规章及专业知识,制定飞机安全间隔预警、飞机高度变化异常、飞机遭遇恶劣天气三类空管复杂事件模式。在真实数据下模拟应用场景以检测上述模式,结果表明系统可在毫秒级处理延迟下检测到空管复杂事件,能为空管工作提供智能化技术支持。 展开更多
关键词 空中交通 复杂事件处理 FlinkCEP 复杂态势 事件检测
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风险动物园(Ⅳ):基于复杂系统思维的风险隐喻事件识别与评估 被引量:1
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作者 佟瑞鹏 胡向阳 +1 位作者 王乐瑶 韩吉祥 《中国安全科学学报》 CAS CSCD 北大核心 2024年第2期53-59,共7页
为有效识别与评估风险动物园中不同类型的隐喻事件,比较不同风险隐喻事件存在的差异性,基于复杂系统思维与脆性理论,分别从确定性、普遍性、周期性、稳定性、容忍性和可逆性6个维度识别分析风险隐喻事件,并基于公共安全三角形理论构建... 为有效识别与评估风险动物园中不同类型的隐喻事件,比较不同风险隐喻事件存在的差异性,基于复杂系统思维与脆性理论,分别从确定性、普遍性、周期性、稳定性、容忍性和可逆性6个维度识别分析风险隐喻事件,并基于公共安全三角形理论构建风险隐喻事件评估模型。结果表明:通过复杂系统思维对风险隐喻事件一般性的特征规律进行总结归纳与科学分类,并建立风险隐喻事件多维度定量评估模型,为风险隐喻事件管控提供应用思路和方法逻辑,同时,保证风险隐喻事件建立的科学性和合理性。针对风险隐喻事件的不同认知特点,提出风险管控4P(禁止、暂停、推迟、预防)策略,为组织开展风险事件管控提供参考。 展开更多
关键词 风险动物园 复杂系统 脆弱性 风险隐喻事件 风险评估
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Low complexity SEU mitigation technique for SRAM-based FPGAs
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作者 JIANG Run-zhen WANG Yong-qing +1 位作者 FENG Zhi-qiang YU Xiu-li 《Journal of Beijing Institute of Technology》 EI CAS 2016年第3期403-412,共10页
An internal single event upset(SEU)mitigation technique is proposed,which reads back the configuration frames from the static random access memory(SRAM)-based field programmable gate array(FPGA)through an intern... An internal single event upset(SEU)mitigation technique is proposed,which reads back the configuration frames from the static random access memory(SRAM)-based field programmable gate array(FPGA)through an internal port and compares them with those stored in the radiationhardened memory to detect and correct SEUs.Triple modular redundancy(TMR),which triplicates the circuit of the technique and uses majority voters to isolate any single upset within it,is used to enhance the reliability.Performance analysis shows that the proposed technique can satisfy the requirement of ordinary aerospace missions with less power dissipation,size and weight.The fault injection experiment validates that the proposed technique is capable of correcting most errors to protect spaceborne facilities from SEUs. 展开更多
关键词 static random access memory (SRAM) field programmable gate array (FPGA) single event upset (SEU) low complexity triple modular redundancy SCRUBBING
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Apache Flink复杂事件处理语言的形式语义 被引量:1
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作者 傅宣登 吴志林 《软件学报》 EI CSCD 北大核心 2024年第10期4510-4532,共23页
Apache Flink是目前最流行的流式计算平台之一,已经在工业界得到了广泛应用.复杂事件处理是流式计算的一种重要使用场景,Apache Flink平台定义并实现了一种复杂事件处理语言(简称FlinkCEP).FlinkCEP语法特性丰富,不仅包括常见的过滤、... Apache Flink是目前最流行的流式计算平台之一,已经在工业界得到了广泛应用.复杂事件处理是流式计算的一种重要使用场景,Apache Flink平台定义并实现了一种复杂事件处理语言(简称FlinkCEP).FlinkCEP语法特性丰富,不仅包括常见的过滤、连接、循环等操作,还包括迭代条件、匹配筛选策略等高级特性.FlinkCEP语义复杂,尚缺乏语言规范对其语义进行准确描述,只能通过实现细节来理解,因此对其语义进行形式描述对于开发人员准确理解其语义非常必要.针对FlinkCEP提出一种数据流转换器的自动机模型,该模型包括用于刻画迭代条件的数据变量、存储输出结果的数据流变量、用于刻画匹配筛选策略的迁移优先级等特性.使用数据流转换器对FlinkCEP的语义进行形式建模,并且根据形式语义设计FlinkCEP的查询求值算法,实现原型系统.进一步,生成能够较为全面覆盖FlinkCEP语法特性的测试用例集,利用这些测试用例与FlinkCEP在Flink平台上的实际运行结果进行对比实验.实验结果表明所提出的形式语义与FlinkCEP在Flink平台上的实际语义基本是一致的.而且,对实验结果不一致的情况进行分析,指出FlinkCEP在Flink平台上的实现对于组模式的处理可能存在错误. 展开更多
关键词 流式计算 Flink 复杂事件处理 形式语义 数据流转换器 查询求值
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灾害系统视角下的灾害耦合效应探讨 被引量:4
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作者 孔锋 《灾害学》 CSCD 北大核心 2024年第1期1-5,共5页
灾害耦合效应是灾害风险科学领域关注的焦点议题,与复杂灾害事件具有密切的联系。该文首先从词源角度阐述了“耦合”的内涵,提出了灾害耦合效应的概念,对比了灾害耦合与灾害叠加的差异,阐述了灾害耦合效应的整体性、有序性、动态性和目... 灾害耦合效应是灾害风险科学领域关注的焦点议题,与复杂灾害事件具有密切的联系。该文首先从词源角度阐述了“耦合”的内涵,提出了灾害耦合效应的概念,对比了灾害耦合与灾害叠加的差异,阐述了灾害耦合效应的整体性、有序性、动态性和目的性特征。其次从灾害系统的角度出发,分析了灾害系统结构体系和功能体系及演化过程与灾害耦合效应的联系,提出灾害耦合效应具有灾害形成要素耦合和灾害演化过程耦合,并探讨了两种耦合内在的特征及两者互动作用。再次从复杂灾害事件角度出发,探究了灾害群、灾害链和灾害遭遇与灾害耦合效应的关系,提出灾害演化过程耦合与灾害演化网络视角下的灾害链过程具有一致性,灾害形成要素的耦合与广义的灾害遭遇具有一致性。最后该文提出了加强灾害耦合效应研究与实践的关键点。 展开更多
关键词 灾害系统 灾害耦合 复杂灾害事件 灾害风险科学 复杂系统科学 灾害群 灾害链 灾害遭遇
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基于局部乱序事件排序的复杂事件匹配方法
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作者 夏秀峰 周清怡 +3 位作者 张杨 郗红梅 杨宏伟 邱涛 《计算机工程与设计》 北大核心 2024年第10期2986-2993,共8页
为处理乱序事件流上的复杂事件匹配问题,减少排序开销,在非确定有限状态自动机的基础上提出解析查询指导排序策略和匹配结果反馈排序策略。根据查询内容对事件流进行分解过滤,得到查询所需的子事件流,设计基于堆排序的子事件流合并算法... 为处理乱序事件流上的复杂事件匹配问题,减少排序开销,在非确定有限状态自动机的基础上提出解析查询指导排序策略和匹配结果反馈排序策略。根据查询内容对事件流进行分解过滤,得到查询所需的子事件流,设计基于堆排序的子事件流合并算法。通过匹配过程中自动机的状态,设计算法对自动机状态转移相关的事件实例进行排序。在股票数据集上进行实验,验证了提出方法相较于现有方法在匹配性能上有显著提升。 展开更多
关键词 复杂事件匹配 乱序事件流 非确定有限状态自动机 分解过滤 子事件流 堆排序 状态转移
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血管内超声指导下经皮冠状动脉介入术治疗复杂冠状动脉病变患者的效果
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作者 张浩 郭明凯 张晓东 《中国民康医学》 2024年第3期34-36,57,共4页
目的:观察血管内超声指导下经皮冠状动脉介入术(PCI)治疗复杂冠状动脉(冠脉)病变患者的效果。方法:选取2020年1月至2023年2月该院收治的90例复杂冠脉病变患者进行前瞻性研究,按照随机数字表法将其分为对照组和观察组各45例。对照组采用... 目的:观察血管内超声指导下经皮冠状动脉介入术(PCI)治疗复杂冠状动脉(冠脉)病变患者的效果。方法:选取2020年1月至2023年2月该院收治的90例复杂冠脉病变患者进行前瞻性研究,按照随机数字表法将其分为对照组和观察组各45例。对照组采用常规PCI治疗,研究组采用血管内超声指导下PCI治疗,比较两组手术前后心功能指标[左心室收缩末期内径(LVESD)、左心室舒张末期内径(LVEDD)和左心室射血分数(LVEF)]水平、血管内皮功能指标[内皮素-1(ET-1)、同型半胱氨酸(Hcy)]水平、随访3个月的心血管不良事件发生率、手术成功率和随访3个月的冠脉再狭窄率。结果:术后,研究组LVEF水平高于对照组,LVESD和LVEDD水平均低于对照组,差异有统计学意义(P<0.05);研究组ET-1、Hcy水平均低于对照组,差异有统计学意义(P<0.05);研究组心血管不良事件发生率为8.89%(4/45),低于对照组的24.44%(11/45),差异有统计学意义(P<0.05);研究组手术成功率高于对照组,冠脉再狭窄率低于对照组,差异均有统计学意义(P<0.05)。结论:血管内超声指导下PCI治疗复杂冠脉病变患者可提高手术成功率,改善心功能指标水平,降低血管内皮功能指标水平、心血管不良事件发生率和冠脉再狭窄率,效果优于常规PCI治疗。 展开更多
关键词 血管内超声 经皮冠状动脉介入术 复杂冠状动脉病变 心功能 心血管不良事件 冠状动脉再狭窄
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复杂事件处理中多聚合查询共享方法
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作者 董攀攀 苏航 高红雨 《计算机应用研究》 CSCD 北大核心 2024年第10期3100-3109,共10页
复杂事件处理技术是在持续不断的流数据中检测满足特定事件序列或对匹配的事件进行统计的一种流数据处理技术。在处理带有Kleene操作符的事件趋势聚合查询时,需缓存中间结果来实现不定数量事件序列的匹配,故对查询系统的资源需求较大。... 复杂事件处理技术是在持续不断的流数据中检测满足特定事件序列或对匹配的事件进行统计的一种流数据处理技术。在处理带有Kleene操作符的事件趋势聚合查询时,需缓存中间结果来实现不定数量事件序列的匹配,故对查询系统的资源需求较大。利用多个查询之间存在的共享机会,生成用于指导查询处理的共享计划,可以有效提高事件趋势聚合查询的处理效率。但现有的聚合查询处理方法生成的共享计划无法做到随执行环境的变化而进行实时调整,来支持查询系统的持续高效处理。针对上述问题,提出了一种可以动态更新的多聚合查询共享方法,以支持实时变化的复杂事件检测的持续高效处理。通过提出共享图数据结构和代价模型,实现对所生成共享计划的实时调整,并引入在线增量聚合执行共享方法,进一步提升带有Kleene操作符的事件趋势聚合查询的处理效率。在真实数据集和模拟数据集上分别进行实验,并与其他处理聚合查询的方法进行了实验对比。实验结果表明,提出方法能够有效降低查询延迟,提高整体查询的处理性能。 展开更多
关键词 复杂事件处理 增量聚合 多查询共享 事件趋势
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