检索结果-内蒙古大学图书馆

Local support-based partition algorithm for frequent pattern mining

PATTERN ANALYSIS AND APPLICATIONS 2019年第3期22卷 1137-1147页

作者： Kadappa, Vijayakumar Nagesh, Shivaraju BMS Coll Engn Dept Comp Applicat Data Analyt Res Lab Bangalore 560019 Karnataka India

Frequent pattern (itemset) mining is one of the established approaches for knowledge discovery. Minimizing the number of database scans (I/O overhead) is a challenging task in Frequent itemset mining. partition algorithm is one of the early novel approaches to reduce the database I/O overhead as compared to Apriori algorithm and other related methods. However, partition algorithm suffers from a significant database I/O overhead (that is, it reads the database twice from the secondary storage) and higher time complexity for computation of frequent itemsets in large databases. In this work, an improved partition algorithm is proposed, which reads the database only once and makes use of local support information to avoid further scans of the database. The proposed algorithm outperforms Apriori and partition algorithms and shows closer performance to FP-Growth algorithm, in terms of computational time. The proposed method outpaces FP-Growth algorithm in terms of memory usage and is competitive to other algorithms. In terms of database access time, the proposed method exhibits better performance over FP-Growth, partition and Apriori methods.

关键词： Data mining Frequent itemset mining partition algorithm

来源：评论

学校读者我要写书评

暂无评论

An Improved partition algorithm to Find Large Itemsets in K-dimensional Space 6

An Improved Partition Algorithm to Find Large Itemsets in K-...

引用

6th International Conference on Computer Science and Network Technology (ICCSNT)

作者： Zeng, Bin Yao, Lu Univ Naval Engn Dept Management Engn Wuhan Hubei Peoples R China

ISBN: (纸本)9781538604939

It has been shown that the current partition algorithm suffers from generating a lot of candidate itemsets when the search range is large. Now an improvement algorithm is proposed to find the large itemsets in the database without the constraint of the maximal range. In the improved algorithm, "divide and conquer" approach is used to recursively partition the whole Hadoop file until a disk bucket is reached. At that time, all the large itemsets can be found in a bucket and then two equal-sized partitions are merged. Finally, all the large itemsets in the Hadoop file can be found. The Hadoop file can be used to store the transactions containing the large items such that only the regions in processing are needed to be scanned, which reduces the unnecessary database scan. The experiment shows that the algorithm is better than the traditional algorithm. Also, sensitivity analysis on four parameters is analyzed.

关键词： data mining e-Commerce partition algorithm K-dimensional space Hadoop filesystem

来源：评论

学校读者我要写书评

暂无评论

The Simplifying partition algorithm of Reliability Evaluation to Complicated Medium Voltage Power Distribution Grid

The Simplifying Partition Algorithm of Reliability Evaluatio...

引用

43rd International-Universities-Power-Engineering Conference

作者： Zhou Ling Ding Xiaoqun Yan Huimin Liu Hongliang Hohai Univ Dept Elect Engn Nanjing Jiangsu Peoples R China Nanjing Normal Univ Dept Elect & Automat Engn Nanjing Jiangsu Peoples R China

ISBN: (纸本)9781424432943

Combining with the characteristic of medium voltage power distribution grid, this paper puts forward a simplifying partition algorithm of reliability evaluation to medium voltage power distribution network. At first, the system is simplified;branch sub-feeder is made to be equivalent to an element, so the system is simplified. Then the construction method of adjacency matrix is presented. Finally, the partition algorithm of power distribution network is come into being. Considering that the common tree operating of medium voltage distribution network so the adjacency matrix is stored by making use of sparse technique. During the fault is analyzed and simulated, the fault enumeration time and repeated searching time of switching element is saved greatly. Reliability evaluation has been taken on the bus of the testing system RBTS-4 presented in the literature by applying the algorithm, and the calculating example has shown that the algorithm has high efficiency and engineering practicability.

关键词： Power system Network simplification partition algorithm Reliability evaluation

来源：评论

学校读者我要写书评

暂无评论

Time of day intervals partition for bus schedule using GPS data

引用

TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES 2015年第Nov.期60卷 443-456页

作者： Bie, Yiming Gong, Xiaolin Liu, Zhiyuan Harbin Inst Technol Sch Transportat Sci & Engn Harbin 150090 Peoples R China Southeast Univ Sch Transportat Nanjing 210096 Jiangsu Peoples R China

Time of day partition of bus operating hours is a prerequisite of bus schedule design. Reasonable partition plan is essential to improve the punctuality and level of service. In most mega cities, bus vehicles have been equipped with global positioning system (GPS) devices, which is convenient for transit agency to monitor bus operations. In this paper, a new algorithm is developed based on GPS data to partition bus operating hours into time of day intervals. Firstly, the impacts of passenger demand and network traffic state on bus operational performance are analyzed. Then bus dwell time at stops and inter-stop travel time, which can be attained based on GPS data, are selected as partition indexes. For buses clustered in the same time-of-day interval, threshold values of differences in dwell time at stops and inter-stop travel time are determined. The buses in the same time-of-day interval should have adjacent dispatching numbers, which is set as a constraint. Consequently, a partition algorithm with three steps is developed. Finally, a bus route in Suzhou China is taken as an example to validate the algorithm. Three partition schemes are given by setting different threshold values for the two partition indexes. The present scheme in practice is compared with the three proposed schemes. To balance the number of ToD intervals and partition precision, a Benefit Evaluation Index is proposed, for a better time-of-day interval plan. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Bus schedule Time-of-day intervals partition algorithm Historic GPS data

来源：评论

学校读者我要写书评

暂无评论

Hidden Markov Model and Auction-Based Formulations of Sensor Coordination Mechanisms in Dynamic Task Environments

引用

IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS 2011年第6期41卷 1092-1106页

作者： An, Woosun Park, Chulwoo Han, Xu Pattipati, Krishna R. Kleinman, David L. Kemple, William G. Univ Connecticut Dept Elect Engn Storrs CT 06029 USA USN Postgrad Sch Dept Informat Sci Monterey CA 93943 USA

In this paper, multistage auction-based intelligence, surveillance, and reconnaissance (ISR) sensor coordination mechanisms are investigated in the context of dynamic and uncertain mission environments such as those faced by expeditionary strike groups. Each attribute of the mission task is modeled using a hidden Markov model (HMM) with controllable emission matrices, corresponding to each ISR asset package (subset of sensors). For each HMM-asset package pair, we evaluate a matrix of information gains (uncertainty reduction measures). The elements of this matrix depend on the asset coordination structure and the concomitant delays accrued. We consider three coordination structures (distributed ISR coordination, ISR officer serving as a coordinator, and ISR officer serving as a commander) here. We evaluate these structures on a hypothetical mission scenario that requires the monitoring of ISR activities in multiple geographic regions. The three structures are evaluated by comparing the task state estimation error cost, as well as travel, waiting, and assignment delays. The results of the analysis were used as a guide in the design of a mission scenario and asset composition for a team-in-the-loop experimentation. Our solution has the potential to be a mixed initiative decision support tool to an ISR coordinator/commander, where the human provides possible ISR asset package-task pairings and the tool evaluates the efficacy of the assignment in terms of task accuracy and delays. We also apply our approach to a hypothetical disaster management scenario involving chemical contamination and discuss the computational complexity of our approach.

关键词： Auction algorithm coordination delays hidden Markov model (HMM) information gain (IG) heuristic sensor scheduling partition algorithm sensor assignment

来源：评论

学校读者我要写书评

暂无评论

partitioning Real-Time Applications Over Multicore Reservations

引用

IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS 2011年第2期7卷 302-315页

作者： Buttazzo, Giorgio Bini, Enrico Wu, Yifan Scuola Super Sant Anna I-56127 Pisa Italy Hangzhou Dianzi Univ Hangzhou 310018 Zhejiang Peoples R China

A full exploitation of the computational power available in a multicore platform requires the software to be specified in terms of parallel execution flows. At the same time, modern embedded systems often consist of more parallel applications with timing requirements, concurrently executing on the same platform and sharing common resources. To prevent reciprocal interference among critical activities, a resource reservation mechanism is highly desired in the kernel to achieve temporal isolation. In this paper, we propose a general methodology for abstracting the total computing power available on a multicore platform by a set of virtual processors, to allocate applications independently of the physical platform. The application, described as a set of tasks with precedence relations expressed by a directed acyclic graph, is automatically partitioned into a set of subgraphs that are selected to minimize either the overall bandwidth consumption or the required number of cores.

关键词： Multiprocessor partition algorithm real-time systems resource reservation

来源：评论

学校读者我要写书评

暂无评论

Meteorological Particle Clusters Time-domain Simulation based on Missile-Borne Radar

Meteorological Particle Clusters Time-domain Simulation base...

引用

2023 Cross Strait Radio Science and Wireless Technology Conference, CSRSWTC 2023

作者： Li, Danyang Wu, Dilong Zuo, Yanchun Wang, Rui Liu, Wei Lv, Bing School of Physics Xidian University Shanxi Xi'an China

ISBN: (纸本)9798350358971

As the bandwidth of missile-based radar increases, the influence of meteorological factors on radar detection gradually becomes non-negligible. This paper describes the modeling information of meteorological particle clusters according to the rainfall and cloud particle spectrum equations. An enhanced approach for rapidly simulating the time-domain echo of meteorological particle clusters is presented utilizing the vector radiative transfer method. This involves streamlining partition acceleration and propagation path judgment in order to optimize the modeling of particle clusters with significant volume. The proposed method exhibits a 20 times improvement in echo modeling time compared to the conventional method. © 2023 IEEE.

关键词： meteorological particles missile-borne radar partition algorithm vector radiative transfer method

来源：评论

学校读者我要写书评

暂无评论

Collaborative optimization allocation of VDAPFS and SVGs for simultaneous mitigation of voltage harmonic and deviation in distribution networks

引用

INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS 2020年 120卷 106034-000页

作者： Tian, Shuya Jia, Qingquan Xue, Shiwei Yu, Hao Qu, Zhengwei Gu, Tianyi Yanshan Univ Key Lab Power Elect Energy Conservat & Motor Dr H Qinhuangdao 066004 Hebei Peoples R China State Grid Heilongjiang Electir Power Co Ltd Elect Power Res Inst Harbin 150030 Peoples R China

This paper proposes a collaborative optimization allocation strategy for voltage-detection active power filters (VDAPFs) with multiple functions and static var generators (SVGs) to improve voltage harmonic (VH) and voltage deviation (VD) of distribution networks (DNs). The integrated voltage sensitivity is defined considering VH and VD simultaneously. According to the local characteristic of power quality (PQ), a partition algorithm based on integrated voltage sensitivity is developed to divide a network into several regions. Two methods based on single and integrated sensitivity are presented to determine dominant nodes as candidates of VDAPFs and SVGs in each region. The corresponding allocations of VDAPFs and SVGs are respectively provided considering the two methods. The sites and sizes of VDAPFs and SVGs are optimized through minimizing the total cost including investment and operation costs by improved particle swarm optimization (PSO) algorithm. An integrated evaluation index based on economy and PQ disturbance mitigation effect is defined to evaluate the performance of the two allocations, thereby determining an optimal allocation. The feasibility and effectiveness of the proposed strategy are verified implemented on IEEE 33-bus system and IEEE 69-bus system by comparing the two allocations with each other and with the conventional allocation strategy.

关键词： Collaborative optimization allocation partition algorithm Power quality (PQ) Static var generators (SVGs) Voltage-detection active power filters (VDAPFs)

来源：评论

学校读者我要写书评

暂无评论

An Accurate Positioning Method for EV Wireless Charging With Array-Placement Coil Set

引用

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2023年 72卷 1页

作者： Qiang, Hao Liu, Donghui Xiao, Feihang Changzhou Univ Sch Mech Engn & Rail Transit Changzhou 213164 Peoples R China Changzhou Univ Jiangsu Prov Engn Res Ctr High Level Energy & Powe Changzhou 213164 Peoples R China

Wireless charging technology significantly improves the flexibility and convenience of electric vehicle (EV) charging. Coil misalignment between transmitting and receiving coils (RC s) will decrease the transmission power and efficiency. To address this issue, this article proposes a high-precision positioning approach based on inductive power transmission with an array-placement coil set. Inductive signal strength (ISS) equations are derived from the working principle of the system model and analysis of the sensing coil (SC) configuration, revealing a positioning algorithm with sector partitioning. The fingerprint map has been designed and optimized to reduce the workload required for table lookup. By dividing the mesh, the proposed partition algorithm based on ISS can realize coil positioning with less reference data to record, shortening the positioning process time. The positioning errors for different mesh widths are examined, and suitable mesh widths are selected to improve positioning accuracy. Finally, the positioning algorithm is implemented on a 20-W wireless charger by building an experimental prototype. Simulation and experimental results indicate that the proposed strategy is effective. When the mesh width is ?(mes )= 5? and r(mes )= 4 cm, the positioning error is less than 2 cm.

关键词： Array-placement coil set coil positioning partition algorithm wireless power transmission

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：