Earticle

The purpose of this paper is to propose a novel modeling approach called Services Ecosystem that applies the concept of ecosystems in ecology to Service-Oriented Software Development and Integration. For this purpose, an ecological system for software systems is proposed for the emerging Service-Oriented Computing paradigm, describing how participants interact with each other within their environments. Three emerging concepts, Service-Oriented Programming, Software Factories, and Service Grid, are employed to explain biotic and abiotic environments. Based upon the Services Ecosystem model, we demonstrate Services Ecosystem Model transformations by using a case example. The Services Ecosystem model is a novel approach for envisioning the Service-Oriented Computing paradigm in terms of an ecosystem in which the roles/perspectives of each participant and their relationships/interactions to environments are clearly described with a holistic view.

In this paper, we implemented an e-mail and chat program (client) for communication between mobile devices and PCs based on WIPI a South Korea's open wireless platform form developing device and content independent software to break from the way of developing contents that is dependent on different wireless platforms to each mobile communications company. While traditional e-mail and chat programs are written for PC-to-PC communication, we develop them for mobile-to-PC and mobile-to-mobile communications, and we expect to see various mobile contents in the future.

It would be desirable to have methods for specific problems, which have low communication costs compared to the computation costs, and in specific applications, algorithms need to be developed and mapped onto parallel computer architectures. Main memory access for shared memory system or global communication in message passing system deteriorate the computation speed. In this paper, it is found that the m-step generalization of the block Lanczos method enhances parallel properties by forming m simultaneous search direction vector blocks. QR factorization, which lowers the speed on parallel computers, is not necessary in the m-step block Lanczos method. The m-step method has the minimized synchronization points, which resulted in the minimized global communications compared to the standard methods.

In this work, we compared several feature selection methods in the field of spam mail filtering. The proposed fuzzy inference method outperforms information gain and chi squared test methods as a feature selection method in terms of error rate. In the case of junk mails, since the mail body has little text information, it provides insufficient hints to distinguish spam mails from legitimate ones. To address this problem, we follow hyperlinks contained in the email body, fetch contents of a remote web page, and extract hints from both original email body and fetched web pages. A two-phase approach is applied to filter spam mails in which definite hint is used first, and then less definite textual information is used. In our experiment, the proposed two-phase method achieved an improvement of recall by 32.4% on the average over the phase or the phase only works.

In this paper, we constructed a two-phase spam-mail filtering system based on the lexical and conceptual information. There are two kinds of information that can distinguish the spam mail from the legitimate mail. The definite information is the mail sender's information, URL, a certain spam list, and the less definite information is the word list and concept codes extracted from the mail body. We first classified the spam mail by using the definite information, and then used the less definite information. We used the lexical information and concept codes contained in the email body for SVM learning in the phase. According to our results the spam precision was increased if more lexical information was used as features, and the spam recall was increased when the concept codes were included in features as well.

Because of unreplenishable power resources, reducing node energy consumption to extend network lifetime is an important requirement in wireless sensor networks. In addition both path length and path cost are important metrics affecting sensor lifetime. We propose a dynamic clustering scheme based on location in wireless sensor networks. Our scheme can localize the effects of route failures, reduce control traffic overhead, and thus enhance the reachability to the destination. We have evaluated the performance of our clustering scheme through a simulation and analysis. We provide simulation results showing a good performance in terms of approximation ratios.

Mobile devices, such as PDAs, portable multimedia players, are more likely to encompass large storage devices with prevalance of high-quality multimedia contents. This paper proposes an object-based multimedia contents storage architecture that employs the object-based storage device model and the iSCSI protocol. It also provides a multimedia content player that operates directly with the proposed storage architecture. We implement both the proposed storage architecture and the multimedia content player upon the Linux environment. Performance evaluation by playing MP3 multimedia contents reveals that the proposed storage architecture reduces the total power consumption by 9%, compared with an existing networked storage. This enhancement is mainly contributed to the fact that a large portion of the file system is moved into the object-based multimedia contents storage from the mobile device.

In this paper, a wideband balun of tapered structure using planar microstrip is desigde ad analyzed. The balun structure was fabricated on a Teflon substrate with a thickness of 0.8mm and relative dielectric constant of 2.5. Two back-to back CPW-to-CPS transitions were simulated and optimized using HFSS. A movel plaar balun using tapered structure of microstip to CPW is suggested and designed. The measurement result, the bandwidth for a reflection coefficient better than -10dB of the balun is 2GHz to 8GHz. The planar balun can improved the performance of wide band spiral antenna.

In recent years, embedded systems have become so complex and the development time to market is required to be shorter than before. As embedded systems include more functions for new services, embedded software gradually grow in size, and development costs and time are increasing. In order to overcome this serious matter, we need a customized design and test technique for embedded software. In this paper, we present a software architecture style for embedded software. It facilitates the composition of reusable functions and helps developers to reduce development time. Because the costs associated with revealing errors of embedded software in applications are rising. we propose a test method and tools for target environments.

In this paper, we propose a new fast running FIR filter structure that improves the convergence speed of adaptive signal processing and reduces the computational complexity. The proposed filter is applied to wavelet based adaptive algorithm. Actually we compared the performance of the proposed algorithm with other algorithm using computer simulation of adaptive noise canceler based on synthesis speech. As the result, We know the proposed algorithm is prefer than the existent algorithm.

The disaster prevention information system is to comprehensively support information collection, processing, search and supply in disaster counter measuring activities, as well as to manage information mainly related to natural disasters unilaterally. Building an optimal system in adequate consideration of features and demands in terms of disaster prevention is requested. Suitable infrastructure that can support information technology (IT) in various aspects should be established in order to utilize IT effectively in disaster prevention information. In addition. accuracy, reliability and efficiency as a disaster prevention information system should be equipped with. In this study, a basic framework for the establishment of disaster prevention information system is presented.

Ubiquitous computing environment means the computing environment that has taken its position so closely with the ordinary living so much like air or water. In building up the U-Korea, one of the important issues is the social issue from the drastic increase of senior population. The contemporary society has its distinct trend in increase of senior household following the nuclear family orientation, increase of working parents with the advancement of women in society, unable to support seniors for long distance or short distance of business trip and other reasons that the need of senior welfare has been ever more felt. Accordingly, the Ministry of Government Affairs and Home Administration has developed the wireless paging system to make prompt response system for 119 Rescue when the single senior is encountered with emergency situation that is has been widely provided for the socially neglected people such as single senior, the disabled persons and others. Currently, the wireless paging system is operated as the sub-system for emergency rescue information system, but due to the lack of reliability of product, problems of terminal portable transmitter, receptor and others, rejection of beneficiary and lack of knowledge in use, insufficient management and supervision of managing officers, the efficiency has been declined that there is a need of development for the system. Therefore, this study proposes the context aware information structure of the subject of ubiquitous wireless paging system required for the development of the wireless paging system model of ubiquitous environment that improved the problems of currently operated wireless paging system.

The packet loss problem that occurs in the mobile multicast (MoM) protocol due to designated multicast service provider (DMSP) handoff is investigated through simulation experiments for several DMSP selection policies. Then, two enhanced DMSP schemes are proposed to minimize the packet loss of the MoM protocol with single DMSP. The first scheme uses a backup DMSP and greatly reduces the packet loss rate at the expense of the increased network traffic. The second scheme utilizes the extended DMSP operation and shows many desirable features such as the almost-zero packet loss rate and relatively low network traffic.

In this paper, an algorithm to extract bar-space area is suggested. In a section of bar-code space area the threshold value is computed, and bar and space are extracted according to threshold value. PDF417 is used everyday life and printed in many different materials. The printed PDF417 is especially influenced by various light source. The decision of bar and space is very hard under the change of illumination. The fixed threshold value to distinguish the bar and space can not be applied. in these cases, The proposed algorithm is developed to investigate variable threshold. The variable threshold can be obtained by simple calculation.

As life style becomes to be complicated, lots of support technologies were developed. The bar code technology is one of them. It was renovating approach to goods industry. However, data storage ability in one dimension bar code came in limit because of industry growth. Two-dimension bar code was proposed to overcome one-dimension bar code. PDF417 bar code most commonly used in standard two-dimension bar codes is well defined at data decoding and error correction area. More works could be done in bar code image acquisition process. Applying various image enhancement algorithms, the recognition rate of PDF417 bar code is improved.

The advanced information and communication technology gives vehicles another role of the third digital space, merging a physical space with a virtual space in a ubiquitous society. In the ubiquitous environment, the vehicle becomes a sensor node, which has a computing and communication capability in the digital space of wired and wireless network. An intelligent vehicle information system with a remote control and diagnosis is one of the future vehicle systems that we can expect in the ubiquitous environment. However, for the intelligent vehicle system, many issues such as vehicle mobility, in-vehicle communication, service platform and network convergence should be resolved. In this paper, an in-vehicle gateway is presented for an intelligent vehicle information system to make an access to heterogeneous networks. It gives an access to the server systems on the internet via CDMA-based hierarchical module architecture. Some experiments was made to find out how long it takes to communicate between a vehicle's intelligent information system and an external server in the various environment. The results show that the average response time amounts to 776ms at fixec place, 707ms at rural area and 910ms at urban area.

Wireless sensor networks(WSN) technology has various applications such as surveillance and information gathering in the uncontrollable area of human. One of major issues in WSN is the research for reducing the energy consumption and reliability of data. A system with forward error correction(FEC) can provide an objective reliability while using less transmission power than a system without FEC. In this paper, we propose to use LDPC codes of various code rate(0.53, 0.81, 0.91) for FEC for WSN. Also, we considered node-to-node interference in addition to AWGN channel. The proposed system has not only high reliable data transmission at low SNR, but also reduced transmission power usage.

Various design schemes for network using wireless sensor nodes have been widely studied on the several application areas ranging from the real world information collection to environmental monitor. Currently, the schemes are focused on the design of sensor network for low power consumption, power-aware routing protocol, micro miniature operating system and sensor network middleware. The indoor localization system that identifies the location of the distributed nodes in a wireless sensor network requires features dealing with mobility, plurality and other environmental constraints of a sensor node. In this paper, we present an efficient location system to cope with mobility of multiple mobile nodes by designing a location handler that processes location information selectively depending on the nodes' density in a specific region. In order to resolve plurality of multiple mobile nodes, a routing method for the location system is also proposed to avoid the occurrence of overlapped location data.

The advance of mobile and telematics technologies has produced vehicles with various convenient services for drivers. Specifically lots of researches and several technologies have been developed to provide services of a remote vehicle diagnosis and control. The existing and representative product for a vehicle control is a RCS (remote control system), but it has a problem of short control distance and fragile security. In this paper, a telematics terminal embedded with CDMA and GPS is designed, which can be connected to the Internet. It allows a driver with a cellular phone to remotely diagnosis and control a vehicle via wireless network and SMS.

Bones are dynamic structures, being supported by muscles, tendons, and ligaments. When some or all the structures are disturbed i.e. in fractures, the alignment of the bone in respect to the rest of the body is deranged. This gives rise to axial as well as rotational deformity in three dimensional planes. The correct alignment and position of the long bones are to be maintained to heal the bone in the best possible anatomical and functional position. The objective of this research is to address the problems in the current practice involving surgeon, assistant, fluoroscopy and crude mechanical means and to see if a robotic solution exists to solve the problems of manipulating and reducing long bone fractures. This paper presents various design aspects of the proposed surgeon-instructed, image-guided and robotic system including the system design specification, robot design and analysis, motion control and implementation, and x-ray image processing and incorporation in CAD environment.

In the paper, a proposed VCO based on bondwire inductances and nMOS varactors was implemented in a standard CMOS process. Using the new drain current model and a propagation delay time model equations, the operation speed of CMOS gate will predict the dependence on the load capacitance and the depth of oxide, threshold voltage, the supply voltage, the channel length. This paper describes the result of simulation which calculated a gate propagation delay time by using new drain current model and a propagation delay time model. At the result, When the reverse bias voltage on the substrate changes from 0 voltage to 3 voltage, the propagation delay time is appeared the delay from 0.8 nsec to 1 nsec. When the reverse voltage is biased on the substrate, for reducing the speed delay time, a supply voltage has to reduce. The value of MOSFET is calculated by using new drain current model.

This paper reports design and fabrication of CMOS temperature sensor circuit using MOSIS 0.25um CMOS technology. The proposed circuit has a temperature coefficient of for a wide operating temperature range with a good linearity. This circuit may be applicable to the design of one-chip IC where quartz crystal resonator is directly mounted on CMOS oscillator chips.

This paper deals with a fault detection system design for uncertain nonlinear systems modelled as T-S fuzzy systems with the integral quadratic constraints. In order to generate a residual signal, we used a left coprime factorization of the T-S fuzzy system. From the filtered signal of the residual generator, the fault occurence can be detected effectively. A simulation study with nuclear steam generator level control system shows that the suggested method can be applied to detect the fault in actual applications.

This paper describes a visual control scheme, fuzzy logic system for visual servoing of an autonomous mobile robot. An existing communication autonomous mobile robot always needs to keep the object in image to detect the moving object. This is a problem in an autonomous mobile robot for spontaneous activity. To solve it, some features for an object are taken from an image and then use in the design of fuzzy logic system for decision of moving location and direction of visual servoing contrivance(apparatus). So continuous tracking is possible by moving the visual servoing contrivance. We present some simulation results and further studies in the Section of Simulation and Concluding Remarks.

A algorithm for control and performance of a pulse-density-modulated (PDM) series-resonant voltage source inverter developed for corona-dischange precesses is presented. The PDM inverter produces either a square-wave ac-voltage state or a zero-voltage state at its ac terminals to control the average output voltage under constant dc voltage and operating frequency. Moreover it can achieve zero-current-switching (ZCS) and zero-voltage-switching (ZVS) in all the operating condition for a reduction of switching lost. Even though the corona discharge load with a strong nonlinear characteristics, new high frequency resonant inverter is shown the wide range power control from 5% to 100%.

Wireless Sensor Networks will revolutionize applications such as environmental monitoring, home automation, and logistics. We developed forest fire surveillance system. In this paper, Considering the fact that in Korea, during November to May, forest fires occur very frequently causing catastrophic damages on the valuable environment, Although exists other forest fire surveillance system such as surveillance camera tower, infrared ray sensor system and satellite system. Preexistence surveillance system can't real-time surveillance, monitoring, database and automatic alarm. But, forest fire surveillance system(FFSS) support above. In this paper, we describes a system development approach for a wireless sensor network based FFSS that is to be used to measure temperature and humidity as well as being fitted with a smoke detector. Such a device can be used as an early warning fire detection system and real-time surveillance in the area of a bush fire or endangered public infrastructure. Once the system has being development, a mesh network topology will be implemented with the chosen sensor node with the aim of developing a sophisticated mesh network.

With the increasing use of the Internet improved Internet technologies as well as web-based applications, the uses of e-Learning have also increased the effectiveness of e-Learning has become one of the most practically and theoretically important issues in both Educational Engineering and Information Systems. This study suggests a research model, based on an e-Learning success model, the relationship of the e-leaner's self-regulated learning strategy and the quality perception of the e-Learning environment. This research model focuses on the learning environment and on self regulated learning strategy. The former consists of LMS, learning contents and interaction that are provided by e-Learning and the latter refers to the learners' self-regulated learning strategy. We will show the validity of the model empirically. As result, most of the hypotheses except for H6 suggested in this model were accepted.

Many aspects of the way we work and live in the twenty-first century will be determined by the vast web of Internet. Virtual environments open the door to new identity experiences. Having the possibility to enter in a new community, where any personal information is directly shown to others, is a possibility to experiencing different self and thus to show and build new identities. This paper aims to identify how to relate the perception of cyber identity, loyalty and purchase intention. First, we classified cyber identity into two types, personal and social, and analyzed perception of each identity type. Then we conducted a survey using pre-designed questionnaire and found out factors consisting personal and social identity. Finally we analyzed the effects of these factors on loyalty and purchase intention using Structural Equation Model.

Recently research interest in Knowledge Management (KM) has grown rapidly. Companies regard intellectual capital as important asset and strive to deploy KM in an organization to gain a competitive edge. Many organizations currently engage in knowledge management in order to leverage knowledge both within their organization and externally to their shareholders and customers. Most of the previous research related to KM are dedicated to investigate the role of information technology in extracting, capturing, sharing, coverting organizational knowledge. Knowledge workers, however, are paid less attention though they are the key players in KM activities such as knowledge creation, dissemination, capture and conversion. We regard knowledge workers as a major component of KM and starting point of understanding organizational knowledge activities. Therefore we adopt a method to understand and analyze knowldge workers' social relationships. In this paper we investigate Social Network Analysis (SNA) as a tool for analyzing knowledge network. We introduce the basic concept of SNA and suggest a framework for implementing knowledge network by explaining how SNA can be used for analyzing knowledge network. We also propose a numerical method for identifying knowledge workers using SNA after classifying knowledge workers. The suggested method is expected to help understanding key knowledge players within an organization.

The software reliability growth depends on the testing time because the failure rate varies whether it is long or not. On the other hand, it might be difficult to reduce failure rate for most of the cases are not available for debugging during operational phase, hence, there are some literatures to study that the failure rate is uniform throughout the operational time. The failure rate reduces and the reliability grows with time regardless of debugging. As a result, the products reliability varies with the time duration of these products in point of customer view. The reason of this is that it accumulates the products experience, studies the exact operational method, and then finds and takes action against the fault circumstances. I propose the simple model to represent this status in this paper.