Il Seok Ko

A Study on the Aspects of Successful Business Intelligence System Development

Business Intelligence (BI) Systems are today considered as a major strategic tool of many well-established companies like Lufthansa, TDC Telecom and AT&T. Of course, the knowledge derived from the experience of those companies could be helpful guide in building efficient BI Systems. Thus, this study highlights the main points arisen from the worldwide practice of building successful BI Systems. The managers usually expect from BI Systems the acceleration of their decision-making process while keeping the quality of each decision, the enhancement of their product development cycle, the maximization of the profit from existing product lines and the discovery of new opportunities, the establishment of better marketing with robust CRM. However, more than 50% of BI projects fail to meet these requirements. So this study investigates the critical mistakes commonly made by BI System developers and suggests profound solutions from the best BI practices.

A User Interface for Controlling Information Appliances in Smart Homes

The web user interface offers many advantages; however, a fixed IP address is required to manage each server, it does not have a push function for completion or error messages, it suffers from problems associated with firewalls, and it is slow. To address these issues, we propose an efficient method for controlling information appliances in smart homes that uses a natural language processing technique and an instant messaging system (IMS). The proposed agent-based management system for smart homes provides a user-friendly interface, and can make use of add-on functionalities of the IMS such as voice chatting, SMS, and multimedia. Moreover, the proposed method can be applied using middleware technologies such as Jini [1] UPnP [2], OSGi [4], and HAVi [5].

AN INTELLIGENT SECURITY AGENT FOR A RELIABLE CIPHER SYSTEM USING PINGPONG

An intelligent security agent for a reliable cipher system using a PingPong cipher is proposed. The system contains a security agent for security managements and services. The agent includes an intelligent selection of many security features: encryption processing speeds, encryption methods, encryption algorithms, synchronization methods, network interfaces, user authentications, security-bit levels, the size of synchronization patterns, etc. Furthermore, encryption algorithms with a PingPong-256, -192 and -128 for data confidentiality and a synchronization generator and detector with a SYNPAT-128, -112, -96, -80, and -64 for system stabilization are designed and analyzed.

Design and performance analysis of the web caching algorithm for performance improvement of the response speed

Until now, various web caching replacement algorithms related to this were researched. An aggravation of web object heterogeneity more frequently generates a replacement of a web object, but cannot reflect enough all kinds of characteristics of web object in these traditional replacement techniques. Especially size heterogeneity of an object has an influence on performance of a web caching seriously. Therefore, a study on web caching algorithm with size heterogeneity of an object is required. In this study, we proposed a web object replacement algorithm with heterogeneity of a web object for performance improvement of the response speed. The algorithm is designed with a divided scope that considered size reference characteristic and reduced size heterogeneity on web object. The performance of the algorithm is analyzed with an experiment. With the experiments results, the algorithm is compared with previous replacement algorithms, and its performance is confirmed with 10%-20% elevation of object-hit ratio and an improvement of response speed.

A multilayered digital content distribution using a group-key based on web

Web based distribution of multimedia digital content has been accelerated due to the increase in the use of the Internet. The major issue regarding the design of a multimedia digital content distribution system through the web is to guarantee the security of digital content and to supply a large amount of high quality multimedia digital content to users. This study focused on designing a security technique for each group in a multilayered structure, and on a caching technique, which is based on this security technique, and to improve the users response speed. Using these techniques guarantees the security of digital content distribution. We implemented the prototype and verified the performance of the proposed system through testing.

Strategy of Positioning for LBS on U-Campus

Location-based service is one of the most popular buzzwords in the field of U-city. Positioning a user is an essential ingredient of a location-based system on a U-city. For the outdoor positioning, GPS based practical solutions have been introduced. However, GPS measurement error is too big to be used for U-campus services because the size of a campus is relatively smaller than a city. We propose Relative-Interpolation Method in order to improve the correctness of outdoor positioning. Besides, indoor positioning is necessary for U-campus while GPS signal is not available inside buildings. For the indoor positioning, Cricket, Active Badge, and so on have been introduced. These methods require special equipments dedicated for positioning. Our method does not require such equipments because it determines the users position based on the receiver signal strength indicators (RSSI) from access points (AP) which are already installed for WLAN. The algorithm we are using for indoor positioning is a kind of finger prints method. However our algorithm builds a decision treeinstead of a look-up table in the off-linephase. Therefore, our method is faster than existing indoor positioning methods in the real-timephase. We have integrated our indoor and outdoor positioning methods and implemented a prototype of our indoor-outdoor positioning method on a laptop. Our experimental results are discussed in this paper.

E-commerce Applications of the Hybrid Reasoning Method

Because of the development of information technologies and extension of traditional commerce practices the importance of electronic commerce has been rapidly growing. A successful e-commerce system should provide convenient user interface, easy and efficient search engine, and complete product information that would satisfy users’ requests. In this research we have proposed a hybrid reasoning method that should improve the search results of an e-commerce system. This method employs best practices of rule-based and case-based reasoning. The experiment conducted has demonstrated that hybrid reasoning method improves the performance of the system’s search mechanism.

A Design of the Simulator for Web-Based Load Balancing

Web services are based on a web-based system in which the performance of this system becomes a major factor in determining the quality of services.An improvement in the system performance can be achieved using a typeof load uniformity (hereinafter called load balancing) by producing a cluster system using several server systems from a web service providers point of view. In addition, certain frequently used web objects or objects that will be frequently applied during web caching from a web service users point of view are to be closely related to a nearby web server in clients. This study investigates a method that improves the acceleration performance in a web-based service. A method that distributes loads applied to a web system itself using a dynamic load balancing method, which uses various types of information between nearby servers, was investigated from a web service providers point of view.

A SOLUTION OF REAL-WORLD OCST PROBLEMS WITH A NEW TREE ENCODING-BASED GENETIC ALGORITHM

For embodying and implementing the ubiquitous computing environments, the recent increase in concern for communication systems has been leading the evolution of the theory and technology of the related fields. Among these network-related problems, the minimum spanning tree (MST) problems have many applications in the communication systems field, because they are solved as one of the conventional combinatorial optimization problems. In particular, the optimal communication spanning tree (OCST) problem is a famous application of the MST problem. The OCST problem is defined by finding a spanning tree that connects all nodes and satisfies their communication requirements for connecting all nodes. This OCST problem can be applied to many network optimization fields, such as network topology design, multicast tree configuration, and ad-hoc network or ubiquitous sensor network routing, etc. This paper presents a genetic algorithm with a new encoding method, which is based on the Prüfer number (PN) and a clustering string, for solving the OCST problems. We will also demonstrate that the efficiency and effectiveness of our proposed method can be shown by several experimental results, employing the proposed method as the solution method of the OCST problems.

A Study on Phonemic Analysis for the Recognition of Korean Speech

This paper is a study related to phonemic analysis of Korean speech. For speech recognition, the best method is that speech should be recognized as phonemic unit. However, to segment speech into phonemic units is not well-applied because of various changes of phonation. Therefore, I in this study try to arrange a phonemic system of Korean speech and segment speech into phonemic units on the base of the phonemic system of Hunminjeongeum, the Korean script. I also look for the features of each phoneme by observing the changes of frequency domain, mel bandwidth and mel capstrum of phoneme and aim to form the phonemic segmentation system of Korean speech.