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Frequently cutting restriction enzymes: Clearing the fog to see the ends
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作者 María I. Vaquero-Sedas Miguel A. Vega-Palas 《American Journal of Molecular Biology》 2013年第1期59-61,共3页
Telomeres, which are found at the ends of eukaryotic chromosomes, are composed of tandem arrays of repetitive sequences and safeguard genomic stability. Previous studies have revealed that telomeric repeats are also p... Telomeres, which are found at the ends of eukaryotic chromosomes, are composed of tandem arrays of repetitive sequences and safeguard genomic stability. Previous studies have revealed that telomeric repeats are also present at internal chromosomal loci in many eukaryotes. However, the biological role of these interstitial telomeric sequences (ITSs) remains unknown. The integrity of telomeric length and chromatin structure is required for telomere stability. However, the study of these telomeric features can be impeded by the presence of ITSs. Frequently cutting restriction enzymes have been revealed to be very useful tools for the study of the length and chromatin structure of telomeres independent of the presence of ITSs. 展开更多
关键词 Telomeric Length Telomeric CHROMATIN Structure frequently CUTTING RESTRICTION ENZYMES Arabidopsis THALIANA
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Oral mucositis induced by risperidone:rare side effect of a frequently prescribed medication
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作者 Andrea Aguglia Andrea Amerio +3 位作者 Luca Proietti Alessandra Costanza Gianluca Serafini Mario Amore 《General Psychiatry》 CSCD 2020年第5期366-368,共3页
Risperidone is a safe second-generation antipsychotic which is rarely associated with the emergence of a few adverse effects,such as oral lesions and stomatitis.We report the case of a 77-year-old woman affected by a ... Risperidone is a safe second-generation antipsychotic which is rarely associated with the emergence of a few adverse effects,such as oral lesions and stomatitis.We report the case of a 77-year-old woman affected by a neurocognitive disorder with psychotic features and treated with risperidone 2 mg/day.After 1 week,she showed a burning mouth syndrome with oral lesions and risperidone was discontinued.Antipsychotic-induced oral ulcerations may be caused by the reduction of saliva protection with minor adverse effects related to oral movement disorders or impairment of the bacterial flora of saliva. 展开更多
关键词 frequent MEDICATION IMPAIRMENT
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THE THEOREM OF THE STABILITY OF LINEAR NONAUTONOMOUS SYSTEMS UNDER THE FREQUENTLY-ACTING PERTURBATION AND ITS APPLICATION IN THE STABILITY ANALYSIS OF ROBOT
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作者 张书顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第11期1057-1063,共7页
The necessary and sufficient condition of the stability of linear nonautonomous system under the frequently-acting perturbation has been given and proved on the basis of[1] and [2], and the theorem of the equivalence ... The necessary and sufficient condition of the stability of linear nonautonomous system under the frequently-acting perturbation has been given and proved on the basis of[1] and [2], and the theorem of the equivalence on the uniform and asymptotical stability in the sense of Liapunov ami the stability under the frequently-acting perturbation of linear nonautonomous system has been given in this paper. Besides, the analysis of the dynamic stabilitv of robot has been presented by applying the theorem in this paper, which is closer to reality 展开更多
关键词 stability nonautonomous system frequently-acting perturbation state transition matrix ROBOT
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THE THEOREM OF THE STABILITY OF NONLINEAR NONAUTONOMOUS SYSTEMS UNDER THE FREQUENTLY-ACTING PERTURBATION—LIAPUNOV’S INDIRECT METHOD
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作者 张书顺 商大中 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第7期717-725,共9页
In this paper the stability of nonlinear nonautonomous systems under the frequently-acting perturbation is studied. This study is a forward development of the study of the stability in the Liapunov sense; furthermore,... In this paper the stability of nonlinear nonautonomous systems under the frequently-acting perturbation is studied. This study is a forward development of the study of the stability in the Liapunov sense; furthermore, it is of significance in practice since perturbations are often not single in the time domain. Malkin proved a general theorem about thesubject. To apply the theorem, however, the user has to construct a Liapunov function which satisfies specified conditions and it is difficult to find such a function for nonlinear nonautonomous systems. In the light of the principle of Liapunov's indirect method, which is an effective method to decide the stability of nonlinear systems in the Liapunov sense, the authors have achieved several important conclusions expressed in the form of theorems to determine the stability of nonlinear nonautonomous systems under the frequently-acting perturbation. 展开更多
关键词 nonautonomous system frequently-acting perturbation uniformly asymptotical stability state transition matrix
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Frequently Asked Questions About Ancient Olympics
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《英语自学》 2000年第8期2-4,共3页
1.Where did the Olympic gamescome from?There are many different stories about the be-ginning of the Olympics.One myth says that the guardians of the infantgod Zeus held the first footrace,or that Zeus himselfstarted t... 1.Where did the Olympic gamescome from?There are many different stories about the be-ginning of the Olympics.One myth says that the guardians of the infantgod Zeus held the first footrace,or that Zeus himselfstarted the Games to celebrate his victory over his fa-ther Cronus for control of the world.Another tradi-tion states that after the Greek hero Pelops won achariot race against King Oenomaus to marry Oeno- 展开更多
关键词 GREEK frequently Asked Questions About Ancient Olympics
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A related degree-based frequent pattern mining algorithm for railway fault data
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作者 Jiaxu Guo Ding Ding +2 位作者 Peihan Yang Qi Zou Yaping Huang 《High-Speed Railway》 2024年第2期101-109,共9页
It is of great significance to improve the efficiency of railway production and operation by realizing the fault knowledge association through the efficient data mining algorithm.However,high utility quantitative freq... It is of great significance to improve the efficiency of railway production and operation by realizing the fault knowledge association through the efficient data mining algorithm.However,high utility quantitative frequent pattern mining algorithms in the field of data mining still suffer from the problems of low time-memory performance and are not easy to scale up.In the context of such needs,we propose a related degree-based frequent pattern mining algorithm,named Related High Utility Quantitative Item set Mining(RHUQI-Miner),to enable the effective mining of railway fault data.The algorithm constructs the item-related degree structure of fault data and gives a pruning optimization strategy to find frequent patterns with higher related degrees,reducing redundancy and invalid frequent patterns.Subsequently,it uses the fixed pattern length strategy to modify the utility information of the item in the mining process so that the algorithm can control the length of the output frequent pattern according to the actual data situation and further improve the performance and practicability of the algorithm.The experimental results on the real fault dataset show that RHUQI-Miner can effectively reduce the time and memory consumption in the mining process,thus providing data support for differentiated and precise maintenance strategies. 展开更多
关键词 High utility QUANTITATIVE frequent pattern mining Related degree pruning Fixed pattern length
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New algorithm of mining frequent closed itemsets
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作者 张亮 任永功 付玉 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期335-338,共4页
A new algorithm based on an FC-tree (frequent closed pattern tree) and a max-FCIA (maximal frequent closed itemsets algorithm) is presented, which is used to mine the frequent closed itemsets for solving memory an... A new algorithm based on an FC-tree (frequent closed pattern tree) and a max-FCIA (maximal frequent closed itemsets algorithm) is presented, which is used to mine the frequent closed itemsets for solving memory and time consuming problems. This algorithm maps the transaction database by using a Hash table,gets the support of all frequent itemsets through operating the Hash table and forms a lexicographic subset tree including the frequent itemsets.Efficient pruning methods are used to get the FC-tree including all the minimum frequent closed itemsets through processing the lexicographic subset tree.Finally,frequent closed itemsets are generated from minimum frequent closed itemsets.The experimental results show that the mapping transaction database is introduced in the algorithm to reduce time consumption and to improve the efficiency of the program.Furthermore,the effective pruning strategy restrains the number of candidates,which saves space.The results show that the algorithm is effective. 展开更多
关键词 frequent itemsets frequent closed itemsets minimum frequent closed itemsets maximal frequent closed itemsets frequent closed pattern tree
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The analysisof frequent adjustments of legal deposit reserve ratio of People's Bank of Ghina
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作者 邓敏 《大观周刊》 2012年第49期100-100,共1页
关键词 金融机构 金融体制 银行业务 PBOC
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Double-layer Bayesian Classifier Ensembles Based on Frequent Itemsets 被引量:3
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作者 Wei-Guo Yi Jing Duan Ming-Yu Lu 《International Journal of Automation and computing》 EI 2012年第2期215-220,共6页
Numerous models have been proposed to reduce the classification error of Naive Bayes by weakening its attribute independence assumption and some have demonstrated remarkable error performance. Considering that ensembl... Numerous models have been proposed to reduce the classification error of Naive Bayes by weakening its attribute independence assumption and some have demonstrated remarkable error performance. Considering that ensemble learning is an effective method of reducing the classifmation error of the classifier, this paper proposes a double-layer Bayesian classifier ensembles (DLBCE) algorithm based on frequent itemsets. DLBCE constructs a double-layer Bayesian classifier (DLBC) for each frequent itemset the new instance contained and finally ensembles all the classifiers by assigning different weight to different classifier according to the conditional mutual information. The experimental results show that the proposed algorithm outperforms other outstanding algorithms. 展开更多
关键词 Double-layer Bayesian CLASSIFIER frequent itemsets conditional mutual information support.
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Accurate querying of frequent subgraphs in power grid graph data 被引量:2
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作者 Aihua Zhou Lipeng Zhu +1 位作者 Xinxin Wu Hongbin Qiu 《Global Energy Interconnection》 2019年第1期78-84,共7页
With the development of information technology, the amount of power grid topology data has gradually increased. Therefore, accurate querying of this data has become particularly important. Several researchers have cho... With the development of information technology, the amount of power grid topology data has gradually increased. Therefore, accurate querying of this data has become particularly important. Several researchers have chosen different indexing methods in the filtering stage to obtain more optimized query results because currently there is no uniform and efficient indexing mechanism that achieves good query results. In the traditional algorithm, the hash table for index storage is prone to "collision" problems, which decrease the index construction efficiency. Aiming at the problem of quick index entry, based on the construction of frequent subgraph indexes, a method of serialized storage optimization based on multiple hash tables is proposed. This method mainly uses the exploration sequence to make the keywords evenly distributed; it avoids conflicts of the stored procedure and performs a quick search of the index. The proposed algorithm mainly adopts the "filterverify" mechanism; in the filtering stage, the index is first established offline, and then the frequent subgraphs are found using the "contains logic" rule to obtain the candidate set. Experimental results show that this method can reduce the time and scale of candidate set generation and improve query efficiency. 展开更多
关键词 POWER grid GRAPH database GRAPH computing Multi-Hash TABLE frequent SUBGRAPHS
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A New Algorithm for Mining Frequent Pattern 被引量:2
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作者 李力 靳蕃 《Journal of Southwest Jiaotong University(English Edition)》 2002年第1期10-20,共11页
Mining frequent pattern in transaction database, time series databases, and many other kinds of databases have been studied popularly in data mining research. Most of the previous studies adopt Apriori like candidat... Mining frequent pattern in transaction database, time series databases, and many other kinds of databases have been studied popularly in data mining research. Most of the previous studies adopt Apriori like candidate set generation and test approach. However, candidate set generation is very costly. Han J. proposed a novel algorithm FP growth that could generate frequent pattern without candidate set. Based on the analysis of the algorithm FP growth, this paper proposes a concept of equivalent FP tree and proposes an improved algorithm, denoted as FP growth * , which is much faster in speed, and easy to realize. FP growth * adopts a modified structure of FP tree and header table, and only generates a header table in each recursive operation and projects the tree to the original FP tree. The two algorithms get the same frequent pattern set in the same transaction database, but the performance study on computer shows that the speed of the improved algorithm, FP growth * , is at least two times as fast as that of FP growth. 展开更多
关键词 data mining algorithm frequent pattern set FP growth
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An Efficient Hybrid Algorithm for Mining Web Frequent Access Patterns 被引量:1
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作者 ZHANLi-qiang LIUDa-xin 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期557-560,共4页
We propose an efficient hybrid algorithm WDHP in this paper for mining frequent access patterns. WDHP adopts the techniques of DHP to optimize its performance, which is using hash table to filter candidate set and tri... We propose an efficient hybrid algorithm WDHP in this paper for mining frequent access patterns. WDHP adopts the techniques of DHP to optimize its performance, which is using hash table to filter candidate set and trimming database. Whenever the database is trimmed to a size less than a specified threshold, the algorithm puts the database into main memory by constructing a tree, and finds frequent patterns on the tree. The experiment shows that WDHP outperform algorithm DHP and main memory based algorithm WAP in execution efficiency. 展开更多
关键词 frequent access pattern AP-tree hash-table
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Model test and numerical simulation on the dynamic stability of the bedding rock slope under frequent microseisms 被引量:9
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作者 Deng Zhiyun Liu Xinrong +4 位作者 Liu Yongquan Liu Shulin Han Yafeng Liu Jinhui Tu Yiliang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第4期919-935,共17页
Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability... Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters. 展开更多
关键词 bedding rock slope frequent microseisms shaking table test numerical simulation dynamic stability failure mode long-term stability
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On-site stormwater detention for Australian development projects: Does it meet frequent flow management objectives? 被引量:1
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作者 Rodney Ronalds Alex Rowlands Hong Zhang 《Water Science and Engineering》 EI CAS CSCD 2019年第1期1-10,共10页
On-site stormwater detention (OSD) is a conventional component of urban drainage systems, designed with the intention of mitigating the increase to peak discharge of stormwater runoff that inevitably results from urba... On-site stormwater detention (OSD) is a conventional component of urban drainage systems, designed with the intention of mitigating the increase to peak discharge of stormwater runoff that inevitably results from urbanization. In Australia, singular temporal patterns for design storms have governed the inputs of hydrograph generation and in turn the design process of OSD for the last three decades. This paper raises the concern that many existing OSD systems designed using the singular temporal pattern for design storms may not be achieving their stated objectives when they are assessed against a variety of alternative temporal patterns. The performance of twenty real OSD systems was investigated using two methods:(1) ensembles of design temporal patterns prescribed in the latest version of Australian Rainfall and Runoff, and (2) real recorded rainfall data taken from pluviograph stations modeled with continuous simulation. It is shown conclusively that the use of singular temporal patterns is ineffective in providing assurance that an OSD will mitigate the increase to peak discharge for all possible storm events. Ensemble analysis is shown to provide improved results. However, it also falls short of providing any guarantee in the face of naturally occurring rainfall. 展开更多
关键词 STORMWATER DETENTION frequent flow management Temporal patterns RUNOFF routing Continuous simulation South East Queensland
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A Novel Incremental Mining Algorithm of Frequent Patterns for Web Usage Mining 被引量:1
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作者 DONG Yihong ZHUANG Yueting TAI Xiaoying 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期777-782,共6页
Because data warehouse is frequently changing, incremental data leads to old knowledge which is mined formerly unavailable. In order to maintain the discovered knowledge and patterns dynamically, this study presents a... Because data warehouse is frequently changing, incremental data leads to old knowledge which is mined formerly unavailable. In order to maintain the discovered knowledge and patterns dynamically, this study presents a novel algorithm updating for global frequent patterns-IPARUC. A rapid clustering method is introduced to divide database into n parts in IPARUC firstly, where the data are similar in the same part. Then, the nodes in the tree are adjusted dynamically in inserting process by "pruning and laying back" to keep the frequency descending order so that they can be shared to approaching optimization. Finally local frequent itemsets mined from each local dataset are merged into global frequent itemsets. The results of experimental study are very encouraging. It is obvious from experiment that IPARUC is more effective and efficient than other two contrastive methods. Furthermore, there is significant application potential to a prototype of Web log Analyzer in web usage mining that can help us to discover useful knowledge effectively, even help managers making decision. 展开更多
关键词 incremental algorithm association rule frequent pattern tree web usage mining
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A novel algorithm for frequent itemset mining in data warehouses 被引量:2
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作者 徐利军 谢康林 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期216-224,共9页
Current technology for frequent itemset mining mostly applies to the data stored in a single transaction database. This paper presents a novel algorithm MultiClose for frequent itemset mining in data warehouses. Multi... Current technology for frequent itemset mining mostly applies to the data stored in a single transaction database. This paper presents a novel algorithm MultiClose for frequent itemset mining in data warehouses. MultiClose respectively computes the results in single dimension tables and merges the results with a very efficient approach. Close itemsets technique is used to improve the performance of the algorithm. The authors propose an efficient implementation for star schemas in which their al- gorithm outperforms state-of-the-art single-table algorithms. 展开更多
关键词 frequent itemset Close itemset Star schema Dimension table Fact table
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Frequent item sets mining from high-dimensional dataset based on a novel binary particle swarm optimization 被引量:2
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作者 张中杰 黄健 卫莹 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1700-1708,共9页
A novel binary particle swarm optimization for frequent item sets mining from high-dimensional dataset(BPSO-HD) was proposed, where two improvements were joined. Firstly, the dimensionality reduction of initial partic... A novel binary particle swarm optimization for frequent item sets mining from high-dimensional dataset(BPSO-HD) was proposed, where two improvements were joined. Firstly, the dimensionality reduction of initial particles was designed to ensure the reasonable initial fitness, and then, the dynamically dimensionality cutting of dataset was built to decrease the search space. Based on four high-dimensional datasets, BPSO-HD was compared with Apriori to test its reliability, and was compared with the ordinary BPSO and quantum swarm evolutionary(QSE) to prove its advantages. The experiments show that the results given by BPSO-HD is reliable and better than the results generated by BPSO and QSE. 展开更多
关键词 data mining frequent item sets particle swarm optimization
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Mining Maximal Frequent Patterns in a Unidirectional FP-tree 被引量:1
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作者 宋晶晶 刘瑞新 +1 位作者 王艳 姜保庆 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期105-109,共5页
Because mining complete set of frequent patterns from dense database could be impractical, an interesting alternative has been proposed recently. Instead of mining the complete set of frequent patterns, the new model ... Because mining complete set of frequent patterns from dense database could be impractical, an interesting alternative has been proposed recently. Instead of mining the complete set of frequent patterns, the new model only finds out the maximal frequent patterns, which can generate all frequent patterns. FP-growth algorithm is one of the most efficient frequent-pattern mining methods published so far. However, because FP-tree and conditional FP-trees must be two-way traversable, a great deal memory is needed in process of mining. This paper proposes an efficient algorithm Unid_FP-Max for mining maximal frequent patterns based on unidirectional FP-tree. Because of generation method of unidirectional FP-tree and conditional unidirectional FP-trees, the algorithm reduces the space consumption to the fullest extent. With the development of two techniques: single path pruning and header table pruning which can cut down many conditional unidirectional FP-trees generated recursively in mining process, Unid_FP-Max further lowers the expense of time and space. 展开更多
关键词 data mining frequent pattern the maximal frequent pattern Unid _ FP-tree conditional Unid _ FP-tree.
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Frequent Itemset Mining of User’s Multi-Attribute under Local Differential Privacy 被引量:2
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作者 Haijiang Liu Lianwei Cui +1 位作者 Xuebin Ma Celimuge Wu 《Computers, Materials & Continua》 SCIE EI 2020年第10期369-385,共17页
Frequent itemset mining is an essential problem in data mining and plays a key role in many data mining applications.However,users’personal privacy will be leaked in the mining process.In recent years,application of ... Frequent itemset mining is an essential problem in data mining and plays a key role in many data mining applications.However,users’personal privacy will be leaked in the mining process.In recent years,application of local differential privacy protection models to mine frequent itemsets is a relatively reliable and secure protection method.Local differential privacy means that users first perturb the original data and then send these data to the aggregator,preventing the aggregator from revealing the user’s private information.We propose a novel framework that implements frequent itemset mining under local differential privacy and is applicable to user’s multi-attribute.The main technique has bitmap encoding for converting the user’s original data into a binary string.It also includes how to choose the best perturbation algorithm for varying user attributes,and uses the frequent pattern tree(FP-tree)algorithm to mine frequent itemsets.Finally,we incorporate the threshold random response(TRR)algorithm in the framework and compare it with the existing algorithms,and demonstrate that the TRR algorithm has higher accuracy for mining frequent itemsets. 展开更多
关键词 Local differential privacy frequent itemset mining user’s multi-attribute
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GTK:A Hybrid-Search Algorithm of Top-Rank-k Frequent Patterns Based on Greedy Strategy 被引量:1
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作者 Yuhang Long Wensheng Tang +4 位作者 Bo Yang Xinyu Wang Hua Ma Hang Shi Xueyu Cheng 《Computers, Materials & Continua》 SCIE EI 2020年第6期1445-1469,共25页
Currently,the top-rank-k has been widely applied to mine frequent patterns with a rank not exceeding k.In the existing algorithms,although a level-wise-search could fully mine the target patterns,it usually leads to t... Currently,the top-rank-k has been widely applied to mine frequent patterns with a rank not exceeding k.In the existing algorithms,although a level-wise-search could fully mine the target patterns,it usually leads to the delay of high rank patterns generation,resulting in the slow growth of the support threshold and the mining efficiency.Aiming at this problem,a greedy-strategy-based top-rank-k frequent patterns hybrid mining algorithm(GTK)is proposed in this paper.In this algorithm,top-rank-k patterns are stored in a static doubly linked list called RSL,and the patterns are divided into short patterns and long patterns.The short patterns generated by a rank-first-search always joins the two patterns of the highest rank in RSL that have not yet been joined.On the basis of the short patterns satisfying specific conditions,the long patterns are extracted through level-wise-search.To reduce redundancy,GTK improves the generation method of subsume index and designs the new pruning strategies of candidates.This algorithm also takes the use of reasonable pruning strategies to reduce the amount of computation to improve the computational speed.Real datasets and synthetic datasets are adopted in experiments to evaluate the proposed algorithm.The experimental results show the obvious advantages in both time efficiency and space efficiency of GTK. 展开更多
关键词 Top-rank-k frequent patterns greedy strategy hybrid-search
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