Proceedings of the 2016 International Symposium on Advances in Electrical, Electronics and Computer Engineering

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67 articles
Proceedings Article

Transmission Performance of 433 Mhz Wireless Sensor Nodes in Through-the-Earth Communication

Xiaoqing Yu, Wenting Han, Zenglin Zhang
Wireless sensor nodes have the advantage of being low-cost easily deployed and of good mobility. However, the significantly high attenuation caused by soil is the main challenge for the communication of between the aboveground node and the underground node. In this paper, experimental measurements have...
Proceedings Article

Efficient Packet Delivery for Underwater Acoustic Sensor Networks

Zhi Ren, Jianbo Zhang
Underwater acoustic sensor networks (UWASN) is an important tool of human to monitor the ocean. However, the existing routing has problem of low packet delivery, the long time end to end delay and the redundant packets. A new routing IGDAR is proposed in this article. The IGDAR select candidate node...
Proceedings Article

Application of Single Point Diamond Turning in Infrared Optics

Shuping Li, Yu Zhang
Non-ferrous metal, crystal material, infrared glass and so on are widely used in the infrared optical system, they can be cut directly by single point diamond turning, so single point diamond turning technology was soon applied to infrared optical elements processing, which can be understood that infrared...
Proceedings Article

The Detection Performance of Sensor on Corrosion Electric Field of Ships

Fuyu Chen, Dingguo Li, Cong Chen, Yamin Feng
The corrosion of related electric field is an important exposure source of warships in sea water, the spread distance of low frequency part can be several kilometers in the sea water, which has a promising application prospects in aspects of remote detection and development of underwater weapon fuze....
Proceedings Article

Comparison and Analysis of the Monte Carlo Simulation and GO Method for the Reliability of Equipment System

Xin Ren
Aiming at the problems of traditional BP neural network in fault diagnosis of equipment, the genetic algorithm is introduced to optimize the network, and the fault diagnosis model of equipment is established. The modeling ideas and considerations are introduced in detail, and the simulation calculation...
Proceedings Article

Analysis of the Causes of Electrical Accidents Caused by Operating Over-voltage of High Voltage Switchgear

Jungang Zhou, Xueming Fan, Ya Liu, Lei Peng
In this paper, the lightning arrester explosion accident and transformer short-circuit accident in power supply system were analyzed in detail. It was found that the operating over-voltage caused by the frequent operation of the 35kV high voltage switchgear was the main cause of the accident. It was...
Proceedings Article

Research on Signal Detection Technology for Flexible Sensor to Monitor the Temperature and Pressure of the Battery

Shufeng Zhang, Ziguan Zhou, Yanbin Song, Shengjie Zhang
In view of the current situation of the storage battery temperature and deformation monitoring is not satisfactory, a flexible sensor signal detection technique for monitoring the temperature and pressure of the battery is presented. The principle and characteristics of the flexible sensor are introduced,...
Proceedings Article

Research and Application of the Sequential Control Logic of Micro Oil Ignition System for Opposed Firing Supercritical Boiler

Bo Lin, Song Gao, Hainan Wu
This paper introduces the application of micro oil ignition technology in Opposed Firing Supercritical Boiler, and the design of the sequential control logic. According to the characteristics and operation mode of micro oil ignition, compared with big oil gun control scheme, the paper study the micro...
Proceedings Article

The Design of Solar Street Lamp Monitoring System Based on ZigBee Wireless Communication Technology

Weiwei Liang, Jungang Zhou, Huanqi Zheng, Minglong Hu
The solar street lamp monitoring system was designed based on ZigBee wireless communication technology in this paper. The design constructed communication network based on ZigBee wireless communication technology, which was included database, B/S architecture combined with geographic information system...
Proceedings Article

Research on the Application of Ant Colony Algorithm in Underwater Path Planning

Wei Feng, Zhe Rao, Zhong Wang
In order to ensure sufficient terrain information for the underwater terrain-aided navigation, a global path planning method based on Ant Colony Algorithm (ACA) is proposed. The concept of feasible region is firstly defined, and then pheromone representation, heuristic functions and pheromone updating...
Proceedings Article

Design of Ultrasonic Liquid Level Sensor Based on STM32 with MODBUS Protocol

Yanlong He, Changzhe Wu, Xiaolin Huo
In the process of blood transfusion in artificial liver, the liquid level of blood inside the dropper must be monitored in real time to ensure the stability and safety of transfusion. According to the requirement of the liquid level detection, we designed a kind of ultrasonic liquid level sensor based...
Proceedings Article

Characteristic Analysis of Seal Type Hydraulic Dumper Based on AMESim

Jungong Ma, Weiping Wang, Qiang Wu
Seal type hydraulic dumper is frequently used in helicopter rotor system to prevent ground resonance and air resonance. In this paper, we modeled the seal type hydraulic dumper with the Hydraulic Component Design database in AMESim and analyzed the impact of driving frequency and gas content of the hydraulic...
Proceedings Article

The Research Overview of Venture Analysis and Performance Evaluation of the Government Emerging Industry Venture Capital Guide Fund

Ziyan Wang, Zhang Mu
This research overview discusses the venture analysis and performance evaluation of the government emerging industry venture capital guide fund. This paper bases on the domestic and overseas research overviews of the government emerging industry venture capital guide fund. Then this paper discusses the...
Proceedings Article

A Kind of Microchannel Heat Sink Optimization for High Power Chips Based on CFD and Non-Silicon MEMS Technology

Dawei Yang, Yan Wang, Guifu Ding, Zhiyu Jin
A kind of distributed array structure micro channel heat sink is studied in this paper. The fluid height and the ratio between fluid and channel are optimized by computational fluid dynamics (CFD) thermal-mechanical coupling method. The typical heat sink is fabricated by UV-LIGA and non-silicon MEMS...
Proceedings Article

A scheme of transmission system in micro robotics based on combined information data

Ziyao Wang, Ye Xue, Zhijie Dong, Ziyuan Li, Congyue Zhang, Yingzi Tan
Traditional inspection robots which equipped with analog camera normally have two channels to transmit image information and control signal. However, this double-channel method causes difficulties in miniaturization of robots. In this paper, we proposed a new scheme in which WIFI technology is utilized...
Proceedings Article

PLC Control System for Translation Motion Stereo-garage

Libo Wang, Lin Lin
A PLC (Programmable Logic Controller) control system for a stacker translation stereo-garage is presented in this paper. Firstly, the overall scheme of the stacker translation stereo-garage is proposed according to user requirement, and the structure scheme and automatic parking and taking flow of a...
Proceedings Article

Performance analysis of DC-DC boost converters based on PV system

Peng Wang, Yan Cui, Danlei Yang
This paper presents the simulation of PV system using Multisim and compare the simulation results with the parameters of the actual solar cell, to analyze the errors. For further study, we prove that a DC-DC boost converter can achieve balance and we can figure out the upper and lower limit value of...
Proceedings Article

The experimental study on 808nm LD end-pumped Nd:YVO4 laser

Caixia Wu, Bo Pang, Wang Qiushi, Yizhuo Zhang
It is discussed that the experimental output profile of 1064 nm beam of a laser diode (LD) end pumped Nd: YVO4 laser. It shows that the output power is highly dependent on the focusing position of pump light inside Nd:YVO4 crystal. Given the same beam waist (1mm) and the same cavity length (58mm), the...
Proceedings Article

Dynamic Simulation Analysis of Off-axis Sensitivity in a Laterally-driven MEMS Inertia Switch

Qihuan Zhang, Zhuoqing Yang, Guifu Ding
A laterally-driven MEMS inertia switch was designed, and its off-axis sensitivity was analyzed and evaluated. The dynamic response process was simulated by ANSYS finite-element model, which indicated that in the designed inertia micro-switch, the distribution of serpentine spring symmetry, the proof...
Proceedings Article

An In-situ Method for Comparing Thermal Conductivity of Insulation Film in MEMS

Zhe Liu, Jiangbo Luo, Guifu Ding
A effective method for comparing the thermal conductivity of insulation film was developed here. The thermal simulation on Ansys software indicated that different materials at same thickness exhibit different temperature distribution in this system. Base on this, the new measurement structure was fabricated...
Proceedings Article

Strengthening of polyimide composites by SiC whiskers

Yanmei Liu, Yan Wang, Guifu Ding
To improve the strength of the polyimide (PI), composites with SiC whiskers doping in the polyimide matrix were prepared. In order to avoid the conglobation of the whiskers, SiC whiskers pre-dispersed in the ethanol. SiC whiskers/PI composites were prepared by high-speed mechanical stirring. The resulting...
Proceedings Article

Characteristics of double planar thin film inductor with Ni-based magnetic film for DC/DC integration

Mingming Chen, Guifu Ding, Mengyuan Zhao
This paper mainly describes the design, fabrication and test of double planar thin film inductor. The thin film inductor has a sandwich structure, which consists of a double-square spiral planar Cu coil between top and bottom Ni magnetic thin films on a glass substrate; it is fabricated by dry and wet...
Proceedings Article

Space Controller Measurement System Based on LabVIEW

Juan Chen, Youwei Zhu, Jian Zhang, Liyang Wang
In order to solve the difficulty in testing space controller, a general measurement system is designed and integrated. Based on LabVIEW, the multi loops model of producer/consumer is chosen to program which makes the interaction and sharing of data came true. Using the structure of state machines, the...
Proceedings Article

XLPE Cable Sheath Circulation Integrated Monitoring Terminal Design

Keqiang Sun, Minghe Zou, Baojun Wang, Zhenhao Wang
In this paper the problems about the practical application of cable sheath circulation online monitoring is analyzed XLPE cable sheath circulation integrated monitoring terminal is designed circuits design principles and parameters of monitoring terminal contains current transformer, circulation detection,...
Proceedings Article

Study on the Optimization of the Smart Oilfield Construction

Jianxi Huang, Bin Zhang
Although the current intelligent oilfield construction is based on the network and other technology such as the internet of things, but it is embodied mainly by individual system, based on fixed localized platform, or established solutions for a particular user. Operating system, remote decision-making...
Proceedings Article

A Novel Complex Network based Credit Risk Management Strategy

Xiangfeng Meng, Yunhai Tong, Xinhai Liu, Shaohua Tan
Financialsystem exhibits a high degree of interdependence. Different typesof interconnections exist among financial agents, such as loanguarantees and cross share-holding. Financial contagion coulddiffuse along the interconnections and lead to wide spreadof risk. Thus how to effectively maintain the...
Proceedings Article

A Formal description for robots understanding knowledge

Yuanxiu Liao, Shengming Zhou, Zhi Li
In the research field of robotics, as can be seen from the description of the classification of the robot, the autonomous robots should have their own knowledge. Generally, a robot’s knowledge refers to the knowledge in the knowledge base of the robot systems. However, Can a robot understand its knowledge...
Proceedings Article

Nginx cluster distribution strategy based on request load information

Yuanlong Ma, Yi Jiang, Zhenwei Zhang
According to the different characteristics of load values of the user’s request,this paperpropose a Nginx cluster load distribution strategy based on the load information request. According to the relationship between the average load information of server cluster and the threshold value, combine with...
Proceedings Article

The preparation of the quasi-Bell-base of entangled squeezed states via atom-cavity-field Raman interaction

Xinhua Cai
In quantum communication and quantum computing, the Bell state acts as an important role. For two qubit of discrete variable, Bell state is composted by two orthogonal to each other's physical state of a physical system. For the physical system consisting of continuous variables, a scheme is presented...
Proceedings Article

Research on Fault Prediction of Electronic Device Based on Subjection Function

Yugang Zhao
In view of the current electronic equipment modular direction development, timely understanding of electronic equipment running status, to prevent failures and shorten the maintenance time, adopt the method of fuzzy membership function, and to quantify the fuzzy state of the equipment, introducing the...
Proceedings Article

A Way of Validating Polynomial Program with Semi-algebraic System

Qinggeng Jin, Lijuan Su, Anping He, Juxia Xiong
Program checking is an interesting and challenging problem. Many kinds of programs can be formulated as polynomial programs, expressing the same meanings in a mathematical way. Moreover, with the mathematic framework of semi-algebraic systems, the polynomial based model checking can be applied directly...
Proceedings Article

A Novel Location Method for Multi-Target Based on the Maximum Likelihood Estimation

Xiantong Ma, Jingqing Luo
In the passive location system, the traditional maximum likelihood estimation (MLE) location method can’t eliminate larger error or wrong parameter automatically, and does not apply to multi-target situation. A novel location method named as position information field for target (PIFT) location method...
Proceedings Article

Study On the Radical Basis Function Neural Network Based On Niche Genetic Algorithms

Zhaohu Deng
When building a radial basis function (RBF) neural network with the traditional clustering method , the expression of the network is often affected by the distribution of training samples.The ability of learning and generalization are hard to achieve the optimum.In this paper, it presents to through...
Proceedings Article

Loneliness Recognition Based on Mobile Phone Data

Zhongqiu Li, Dianxi Shi, Feng Wang, Fan Liu
Nowadays, the definition of health is not only the absence of disease, but both physical and mental health. Loneliness as an important measure of mental health has become a topic that can not be ignored. In this paper, we study the problem about loneliness of individuals can be automatically recognized...
Proceedings Article

A Dynamic Management Mechanism Based on H-Index Secondary Indexes

Heng Qin, Anping Xiong, Yuan Tian
Hbase is a kind of non-relational database providing scalable technology methods and platform for managing big data, but it can only query through the primary key. This paper proposes a secondary index mechanism based on the heat value which derives from H-Index, a secondary index scheme of Huawei. It...
Proceedings Article

Periodic Pattern Mining Based on GPS Trajectories

Xiaopeng Chen, Dianxi Shi, Banghui Zhao, Fan Liu
With the rise of LBS (Location Based Service), lots of user recommendation system based on location trajectory analysis has emerged. Finding periodic behavior is essential to analysis user’s activity. In order to solve the problems with trajectory outliers and human intervention in periodic parameters,...
Proceedings Article

Resource Information Retrieval Method Based on Name Service in Intelligent Agriculture

Xiaolong Luo, Ye Tian, Anping Xiong
Intelligent agriculture is the inevitable development trend of modern agriculture. Sharing the sensing data of agricultural production activities on internet to make it to be found is the premise of agricultural products supervision and agricultural decision. However, the relationship between agricultural...
Proceedings Article

A Study on the Classification of Dongba Literature

Yujing Chen, Ning Li, Xueqiang Lv
With dongba culture researches increasing year by year, there needs to be a highly efficient classification method to classify research achievements creating conditions for further study. Aiming at the shortcomings of the traditional mutual information method, giving full consideration to the factors...
Proceedings Article

A Kind of Collaborative Filtering Algorithm Based on User Clustering and Time Stamp

Shuqin Li, Xiaohua Yuan, Huaimei Han
In the case of user rating data is very large and sparse, the effect of traditional collaborative filtering algorithm in use recommendation is unsatisfactory. In this paper, a collaborative filtering algorithm based on user clustering and time stamp is proposed. Which first clusters the users according...
Proceedings Article

A FPN Parameter Optimization Method Based on CDEDPSO

Qiumin Fan, Bing Xu
For the uncertain change characteristics of transition matrix parameters in complex FPN system,this paper presents a parameters optimization algorithm based on CDEDPSO.This article focuses on the weight, threshold and certainty of FPN optimized model and these parameters are analyzed, improved and simulated...
Proceedings Article

Construction of Regular and Irregular QC-LDPC Codes: a Finite Field Approach and Masking

Xiaopeng Chen, Lin Zhou, Rui Zhao, Yucheng He
Quasi-Cyclic Low-Density Parity-Check (QC-LDPC) codes require less hardware resources due to the quasi-cyclic structure of parity-check matrices. In this paper, two improved methods for constructing QC-LDPC codes are proposed. Firstly, in order to make sure the masked LDPC codes have flexible code rate...
Proceedings Article

Using GP/PARI to Compute Tame Kernel

YongSheng Ma
A new method for proving to be an isomorphism was presented. Based on the method, an algorithm was presented to prove to be an isomorphism, which can be implemented in the GP/PARI.
Proceedings Article

Congruent Numbers and The Rank of Elliptic Curves

Yuanbo Liu
Let p and q be prime with and ,and let . If , then is a congruent if and only if the equation has rational solutions. And The Birch Swinnerton-Dyer conjecture predicts that the rank of is one.
Proceedings Article

Bayesian Energy Detection Based on Temporal Persistence

Renyang Gao, Shengliang Peng, Rui Zhao, Weibin Zheng
Energy detection is one of the classical methods for spectrum sensing in Cognitive radio (CR). Previous research on energy detection is almost based on single time slot, while the communication process of the primary user (PU) is hardly completed in one time slot. In this study, the authors consider...
Proceedings Article

FPGA implementation of Reed-Solomon Codes Based on Visible Light Wireless Communication System

Lipeng Qiu, Xiaopeng Chen, Lin Zhou, Yucheng He
The research of visible light communications(VLC) has became a focus of wireless communications in recent years. In this paper, the channel coding technique for VLC systems were studied. According to the characteristics of VLC channel, RS codes were designed to correct the burst and random errors. The...
Proceedings Article

The Study of Wavelet Analysis in Line Selection of Single-Phase Earth Fault in Medium Voltage Distribution Network

Changzhi Lv, Fei Peng
On the basis of detection fault line research about abstraction transient fault information in ground system, the fault line could be selected because of its high frequency transient current. After we discussed and analyzed the wavelet criteria of the detected signal in theory, the significant amplitude...
Proceedings Article

A Mobile Anchor Node Positioning Algorithm for WSN in Three-dimensional Space

Xiaochao Dang, Fenfang Li, Zhanjun Hao
In wireless sensor network, in order to effectively reduce the influence of the complex environment in node localization accuracy, based on trilateral plane positioning algorithm, this paper proposes an algorithm about the mobile anchor node and fuzzy information (Mobile Anchor Node Localization on Fuzzy...
Proceedings Article

Design and Implementation of Management System for Training Model of Sustainable Development

Lin Zhou
To achieve the management systems of vocational school’s training mode for sustainable development, we developed it with the .NET and using ASP.NET, SQL Sever2000 database and so on for designing, by building a information system of sustainable personnel training mode, analyzing each component of management...
Proceedings Article

The key technology research for the back-EMF method of BLDCM

Yu Zhou, Bin Hu, Hai Huan Zong
The direct current motor (DCM) is widely applied in industrial field. The presence of brush and commutator in traditional DCM result in sparks and noise, and may reduce working life of the motor, therefore, the research for brushless direct current motor (BLDCM) becomes hot. When the motor running, the...
Proceedings Article

Optimization Method of Technical Solutions in Premium Power Park Considering Customers’ Power Quality Demand

Liu Xuna, Li Da, Zhao Dawei
Premium Power Park (PPP) is a technical solution to solve the regional high-quality power supply problems. The technical optimization method is the premise of planning and constructing. To meet various power demands of different customers, the concept of process immunity time is lead up in this paper....
Proceedings Article

Research on Error Ratio Calculator for the Electric Energy Meter Error Calibrator Device

Jun Chen, Yu Guo, Yinglong Chen
With the rapid development of national economy, electric energy which is considered to be an important energy source has obtained wide application in all sectors of society. Electric energy meter is regarded as the main instrument in current measurement and economic settlement. Its accuracy has a direct...
Proceedings Article

Discussion on the evaluation model of University Digital Campus Based on AHP

Lu Li, Xiangui Xue
This research aimed at the present situation of the University digitization, using level analysis method to screen the digital evaluation factors. It established the digital campus evaluation model of colleges and universities , to expect that the application of digital campus can play its proper role.
Proceedings Article

Edge Subdivision Algorithm Analysis Based on the Color Linear CCD

Ziyang Xu, Guoxin Ma
Because of the linear CCD is used in non-contact dimensional measurement, especially at the edge of the detects object, the edge of the object can not be well coincided with the pixel edge of the sensor, there will be some errors. Currently, in order to reduce this errors, there are some edge subdivision...
Proceedings Article

Low-angle estimation method for meter-wave radar via matrix completion

Qichao Ge, Yongshun Zhang, Shanshan Ding
The deficiencies of array elements causes the decrease of angle survey precision when detect low-angle estimation. In order to solve this problem, this paper transform the data missing matrix which isn’t meeting the condition of the SIP into appropriate one based on the MC theory by using the Hankel...
Proceedings Article

Dynamic Community Detection Algorithm Based On Hidden Markov Model

Zhe Dong
The HMM_DC algorithm is proposed based on the Hidden Markov Model to detect the community in dynamic social network. The algorithm transforms the community detection problem to get the optimal status chain in Hidden Markov Model with considering the history information and characteristics in dynamic...
Proceedings Article

2D cross entropy method for image segmentation based on artificial bee colony optimization

Xianglan Ye, Tianhuang Chen
A kind of image segmentation method with two-dimensional cross entropy was proposed based on the artificial bee colony algorithm to overcome the large amount of calculation and long computing time. Firstly, the principle of two-dimensional cross entropy threshold segmentation was analyzed. Then, the...
Proceedings Article

Recognition Method for Emoticons Based on Network Text

Yiming Lei, Yong Liu, Hua Huo
Emoticons are widely used in the network text, which has enhanced effect for the author's emotional experience and semantic representation. Effective identification of the emoticons in the network text has great significance to sentiment analysis, public opinion survey and commercial investigation. Through...
Proceedings Article

Benchmark of a parallel fluid code for parametric decay instability in inhomogeneous plasmas

Xinfeng Sun, XiaoHong Wang
A nonlinear and parallel fluid code is developed to solve the full space-time domain coupled two-fluid plasma and Maxwell equations and is used to investigate the parametric decay instabilities (PDIs) of the inhomogeneous plasma. Under the laser plasma parameters of nuclear fusion, the threshold power...
Proceedings Article

High-resolution direction-of-arrival estimation using Khatri-Rao product and spatial sparsity of sources

Shanshan Ding, Ningning Tong, Qichao Ge
Algorithms based on Khatri-Rao (K-R) product improve the degree of freedom (DOF) of virtual arrays and thus more source angles can be estimated. However, the estimation accuracy is not satisfying. In this paper, a method considering spatial sparsity (SS) of sources in K-R subspace is proposed to estimate...
Proceedings Article

Meter Reading Scheme Based on Automatic Switching between Two Local Communication Channels

Guiping Deng, Tiejie Wang, Miao Zhou
This paper presented the meter reading scheme based on automatic switching between two local communication channels of power line carrier and micro-power wireless. Firstly, the structure of the meter reading system based on automatic switching between two local channels of power line carrier and micro-power...
Proceedings Article

Contrast based Saliency Detection via Manifold Ranking

Shunyao Jin, Xueqing Li
Saliency detectionhas been widely studied in computer vision. In this paper we propose a two-steps method combining contrast assumption and ranking technology to detect saliency region. Firstly, We use the traditional contrast assumption to find foregroundcues. Then we rank the nodes with labeled contrast...
Proceedings Article

An Intrusion Detection System Based on Big Data for Power System

Sicheng Zeng
On the background of information and energy interconnection, the whole power system generated a huge amount of data with diverse structure, complicated sources and large scale from both cyber devices and physical components, which is a typical cyber-physical system (CPS). These data exhibit data feature...
Proceedings Article

Automatic On Load Voltage Regulating Technology and Energy-saving HID Lamps

Jinlong Tu, Yanxia Li
This report analyses the current typical non-contact On-Load Tap Changer(OLTC) thyristor products, poses the circumfluent calculating formula, and points out the main problems existed. The paper also introduces the highly-performed and highly-reliable thyristor OLTC technology and products. Compared...
Proceedings Article

Android Mobile Forensic Sciences Research

Jiang Du, Bin Guo
According to the characteristics of electronic evidence,the storage mechanisms of Android phone and specific operational problems encountered in forensic work are summarized,this article presents a relatively standardized evidence-based policy Android phones, hoping to improve the Android mobile phone...
Proceedings Article

An Improved Region Contrast and Global Distribution Saliency Detection algorithm

Xiaohong Hao, Yifang Yuan, Wanfei Jiang
According to the local contrast and global distribution of an image, this paper detecting salient images through bottom-up data driven . First, this paper using adaptive segmentation method divided image into non-overlapping images, improved Block and Chessboar distance from a linear combination to replace...
Proceedings Article

Modeling and Simulation of Torpedo Leading Angle Variety With Observation Errors

Kai Zhan, Jing Wang
The straight-shooting is the torpedo’s important shooting method and its leading angle is key factor. Based on the theory of the torpedo straight-shooting triangle, modeling and discussing the torpedo leading angle variety caused by the target observation errors in straight-shooting. And simulations...
Proceedings Article

A Review of the Maximal Frequent Itemset Mining Algorithms over Dynamically Changed Data

Haifeng Li
Maximal frequent itemset mining is a very important method in mining frequent itemsets, which will reduce the mining meory cost and supply a better understanding of the rules generated by the frequent itemsets. In this paper, we review the maximal frequent itemset mining algorithms over a stream, which...