Keji Mao

Utilize Fuzzy Data Mining to Find the Travel Pattern of Browsers

With the traveling records of browsers, one can analyze the preference of pages, further understand the demands of consumers, and promote the advertising and marketing. In this study, we use maximum forward reference (MFR) algorithm to find the travel pattern of browsers from Web logs. Simultaneously, experts are asked to evaluate the fuzzy importance weightings for different Webs. At last, we employ fuzzy data mining technique that combines Apriori algorithm with fuzzy weights to determine the association rules. From the yielded association rules, one can be accurately aware of the information consumers need and which Webs they prefer. This is important to governmental institutions and enterprises. Enterprises can find the commercial opportunities and improve the design of Webs by means of this study. Governmental institutions can realize the needs of people from the obtained association rules, make the promotion of policy more efficiently, and provide better service quality

Study on Tree-Based Clustering MDS Algorithm for Nodes Localization in WSNs

Localization of sensors nodes is a key and fundamental issue in WSNs due to random deployment. In this paper, we propose a tree based clustering (TBC) multidimensional scaling algorithm for wireless sensor networks with the purpose of overcoming the shortage of classical MDS algorithms in its localization accuracy and computing complexity. Clustering is adopted to degrade the problem scale in our approach and a moderate number of common nodes between clusters are kept during clustering. Inner cluster local coordinates are calculated and then mapped into global coordinates according the tree structure formed by clustering. The simulations on MATLAB are conducted and the results show that the proposed algorithm has better localization coverage and higher accuracy than the traditional MDS based algorithms.

Data Storage Scheme Supporting for Multidimensional Query

The query and storage of data is very important in wireless sensor networks (WSN). It is mainly used to solve how to effectively manage the distributed data in the monitored area with extremely limited resources. Recent advances in technology have made the number of the sensing modules in one sensor develop from single to multiple. The existing storage scheme for one-dimensional data is not suitable for the multidimensional data or costs too much energy. We proposed a kind of data storage scheme supporting multidimensional query inspired by K-D tree. The scheme can effectively store the high-dimensional similar data to the same piece of two-dimensional area. It can quickly fix the storage area of the event by analyzing the query condition and then fetch back the query result. Meanwhile the scheme has a certain degree of robustness to packet loss and node failure. Finally the experiment on the platform of Matlab showed that our scheme has some advantages compared with the existing methods.

Data-Centric Routing Mechanism Using Hash-Value in Wireless Sensor Network

Traditional routing protocols as TCP/IP can not be directly used in WSN, so special data-centric routing protocols must be established. The raised data-centric routing protocols can not identify the sensor nodes, because many nodes work under a monitoring task, and the source of data is not so important some times. The sensor node in the network can not judge weather data is come from the some sink node. What’s more, the traditional method use IP to identify sensors in Internet is not suitable for WSN. In this paper, we propose a new naming scheme to identify sensor nodes, which based on a description of sensor node, the description of a sensor node is hashed to a hash value to identify this sensor. The different description generates different identifier. Different from IP schema, this identifier is something about the information of the sensor node. In the above naming scheme, we propose a new data-centric routing mechanism. Finally, the simulation of the routing mechanism is carried out on MATLAB. The result shows our routing mechanism’s predominate increase when network size increase.

Beacon moving location algorithm in WSN

Location is one of the key technologies in Wireless Sensor Networks WSN. A lot of location algorithms assume that beacon nodes are fixed, but in most practical applications, the locations of some beacons will be changed after deployment, which leads to other unknown nodes rely on these beacons cannot be accurately located. In this paper we proposed an Area Division-based Beacon Movement Detection Algorithm AD-BMD to solve the location problems with beacons movement, through two judgement processes to determine which beacon have moved, and set a coordinate confidence value for each beacon. We also proposed a Beacon Movement Detection based Beacon Optimal Selection Location Algorithm BMD-BOS to use moving and unmoving beacons more reasonably, by selecting beacons reasonably to calculate the position of unknown nodes. Experimental results show that AD-BMD has high-correct rate and low-error rate. Compared with LB and SSV, AD-BMD has better performance. The location accuracy of BMD-BOS is much higher than N-BMDs and D-BMDs.

Clustering problem using adaptive genetic algorithm

Clustering is very important to data analysis and data minig. The K-Means algorithm, one of the partitional clustering approaches, is an iterative clustering technique that has been applied to many practical clustering problems successfully. However, the K-Means algorithm suffers from several drawbacks. In this paper, an adaptive genetic algorithm be present , it solve disadvantages of K-Means by combine parallel genetic algorithm, evolving flow and adaptive. Experimental results show that the adaptive genetic algorithm have advantages over traditional Clustering algorithm.

RI-MDS: multidimensional scaling iterative localization algorithm using RSSI in wireless sensor networks

To improve the feasibility and the convenience of localization methods for wireless sensor networks, a localization algorithm RI-MDS (RSSI-based iterative-multidimensional scaling) is proposed. The RI-MDS method is centralized and mainly focuses on improving localization accuracy. It collects RSSI vectors as ranging basis and combines the metric MDS method and the nonmetric MDS method to accomplish the relative localization. Then it uses the maximum likelihood method in affine transformation to transform the relative coordinates to absolute ones. Our method has no need for additional equipment on the WSN nodes. Simulation and field experiments show that the average localization error and the localization error ratio of the RI-MDS method are relatively lower and thus they are more feasible.

RI-MDS: Multidimensional Scaling Iterative Localization Algorithm Using RSSI in Wireless Sensor Networks

To improve the feasibility and the convenience of localization methods for wireless sensor networks, a localization algorithm RI-MDS (RSSI-based Iterative-Multidimensional Scaling) is proposed. The RI-MDS method is centralized, and mainly focuses on improving localization accuracy. It collects RSSI vectors as ranging basis, and combines the metric-MDS method and the nonmetric MDS method to accomplish the relative localization. Then it uses the maximum likelihood method in affine transformation to transform the relative coordinates to absolute ones. Our method has no need for additional equipment on the WSN nodes. Simulation and field experiments show that the average localization error and the localization error ratio of the RI-MDS method is relatively lower, thus it is more feasible.

The Design and Implementation of an Ordering System for Restaurants Based on 3G Platform

An ordering system can help restaurants to increase the efficiency in ordering process. In this paper, we designed and implemented an ordering system for restaurants based on 3G platform. The system provides both customers and waiters a customized handheld 3G terminal to view up-to-date menu and issue ordering commands, and the system will quickly forward the order to kitchen to notify chefs to prepare dishes. With this ordering system, restaurants can greatly reduce operation cost, and improve their customer satisfaction.

Design of the multimedia communication protocol and system for wireless LAN

The protocol of wireless LAN —IEEE 802.11 put forward DCF/PCF to offer the real time transmission, but it did not meet the need of multimedia transmission, so a new MAC protocol is developed to solve this problem. In this paper we discuss the way of implementing and processing the multimedia data streams in WLAN. We regard the transmission of multimedia as multi-channel accessing with synchronization to study it. We start from the parameter QoS and mapped the multimedia transmission data streams to the different priorities, and use negotiation approach to allocate the resource.