• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1131-1138
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• 2015

As the size of the internet market grows rapidly, the number of IPv4 addresses available is being exhausted, while transition to IPv6 is being delayed. As the best alternative solution, Network Address Translation(NAT) scheme is being used. It connects the public internet network with the private internet network in order to reduce the waste of IPv4 addresses space. The purpose of this paper is to study the effective example of network based on common virtual network using Packet Tracer with topology designed rather than usual theoretical approach in Dynamic NAT and PAT, which allows more efficient use of address space.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1205-1210
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• 2004

The 4-20mA analog signal used in the various industrial fields to interface sensor in distributed process control has been replaced with relatively simple digital networks, called "fieldbus, and recently by Ethernet. Significant advances in Internet and computer technology have made it possible to develop an Internet based control, monitoring, and operation scheduling system for heating, ventilation and air-conditioning (HVAC) systems. The seamless integration of data networks with control networks allows access to any control point from anywhere. Field compatible field devices become so-called "smart" devices, capable of executing simple control, diagnostic and maintenance functions and providing bidirectional serial communication to higher level controller. The most important HVAC of BAS has received nationwide attention because of higher portion of more than 40% in building sector energy use and limited resources. This paper presents the Internet-based monitoring and control architecture and development of LonWorks control modules for AHU (air handling units) of HVAC in viewpoint of configuring BAS network. This article addresses issues in architecture section, electronics, embedded processors and software, and internet technologies.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1545-1549
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• 2005

According as computer is supplied in a lot of homes and offices and Internet use increases, various service based on the Internet. Including wireless PDA in the future, many devices such as Internet telephone, TV, refrigerator and oven will be connected on the Internet and Internet address exhaustion will be raised to serious problem gradually. Today, the IPv4 address exhaustion problem has been solved partially using NAT (Network Address Translation) however, the transition to next Generation Internet will be accelerated because of advantages such as mobility, security service, QoS, and abundant IP addresses. In IPv6, all hosts are designed to create and set their address automatically without manager's intervention using Neighbor Discovery Protocol. But, when an IPv6 host sets its address automatically, there are serious security vulnerabilities. In this paper, we analysis security vulnerabilities in auto-configuration and provide security requirements for secure auto-configuration.

• Journal of Korean Society for Quality Management
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• v.31 no.2
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• pp.51-68
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• 2003

This research addresses familiarity and degree of using Internet site and trust building to affect service quality in e-commerce. We assume that the familiarity and frequency of using Internet site affect perceived service quality of customer. Also it assumes that customer's trust building intermediates their relationships. Several hypotheses are set to test these assumptions empirically. Consequently, the results show that familiarity of using Internet site affects customer's perceived service quality significantly except for tangible. Also it is found that degree of customer's trust building intermediates the relationship between familiarity of using Internet site and customer's perceived service quality significantly. For gaining good trust of customer in Internet site, we suggest that familiarity should fit into customer's needs.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.5
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• pp.23-30
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• 2009

This paper addresses the design of trTCM (Two Rate Three Color Marker) described in RFC2698. It has proposed for trTCM to be used in Differentiated Service network that provides AF PHB (Assured Forwarding Per Hop Behavior). trTCM is the marker with the metering function, and consists of the token updating function and the marking function. The token updating function uses the dual token bucket. The marking function compares the token values with the length of input packet and then marks the result into IP QoS field (ToS field). In this paper, we design trTCM function and then addresses the scheme to implement it using FPGA technology.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.35-40
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• 2013

The messages on mobile terminal may contain context information such as user's location, time and preference. This paper proposes message forwarding system based on user's context. The server stores the predefined target addresses which may be mobile phone number, web server address and email address. On request for message transmission, the server tries to find a target address matching a user's context. Thus, a sender transmits messages to a representative address without knowing various receiver's addresses and a receiver can retrieve classified messages according to subject/location.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.10
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• pp.1221-1232
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• 2016

Even though there have been a surge in demand for Internet addresses, but the existing IPv4 addresses are virtually depleted. Therefore, the conversion of IPv6 is being made consistently and the need for systematic situation grasp for IPv6 adoption through the measurement index of the IPv6 is on the rise. This study investigated domestic and overseas IPv6 usage measurement techniques and cases. Through evaluating existing measurement indices, this study derives the improved indices of measuring IPv6 usage and proposes the implementation methods of them.

• Journal of Information Technology Services
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• v.10 no.3
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• pp.203-212
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• 2011

In the every day life of the people, the Internet is widely used. Currently over 1.9 billion people have one or more email addresses and over 600 million people use the Facebook. People are collaborating via the Internet more and more. When people are collaborating through the Internet, the differences of the message delivery delay are the biggest problem that disturbs the collaborative work over the network. To solve the differences of the message delivery delay, we introduce the delay-gap method. An experimental code have been implemented and the efficiency of the delay-gap is presented through the results from the experiment that have many participants.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.4
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• pp.151-161
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• 2005

For Internet service providers (ISPs), there are three common types of interconnection agreements : private peering, public peering and transit. One of the most important problems for a single ISP is to determine which other ISPs to interconnect with, and under which agreements. The problem can be then to find a set of private peering providers, transit providers and Internet exchanges (IXs) when the following input data are assumed to be given : a set of BGP addresses with traffic demands, and a set of potential service providers (Private peering/transit providers and IXs) with routing information, cost functions and capacities. The objective is to minimize the total interconnection cost. We show that the problem is NP-hard, give a mixed-integer programming model, and propose a heuristic algorithm. Computational experience with a set of test instances shows the remarkable performance of the proposed algorithm of rapidly generating near-optimal solutions.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.302-308
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• 2006

We introduce the concept of a remote distributed embedded system to integrated fieldbus based control systems in internet/Intranet. As a result fieldbus systems are opened up for remote monitoring, remote maintenance, and remote control applications using state of the art Web-technology. This paper addresses the design of a remote distributed embedded system using Internet and CAN for multi-Induction motor of Building and Industrial field. The fieldbus used the CAN based networked intelligent multi-motor control system using DSP2812 microprocessor. To build such a system, the TCP/IP-CAN Gateway which convert a CAN protocol to TCP/IP protocol and vice verse, was designed. A experimental simulation system consists of a TCP/IP-CAN Gateway in remote place and a command PC ti be connected ti Ethernet.