• KIPS Transactions on Computer and Communication Systems
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• v.9 no.3
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• pp.45-58
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• 2020

In the current trend of increasing network traffic due to the popularization of cloud service and mobile devices, WAN bandwidth is very low compared to LAN bandwidth. In a WAN environment, a WAN optimizer is needed to overcome performance problems caused by transmission protocol, packet loss, and network bandwidth limitations. In this paper, we analyze the data deduplication algorithm of WANProxy, an open source WAN optimizer, and evaluate its performance in terms of network latency and WAN bandwidth. Also, we evaluate the performance of the two-stage compression method of WANProxy and Zstandard. We propose a new method to improve the performance of WANProxy by revising its data deduplication algorithm and evaluate its performance improvement. We perform experiments using 12 data files of Silesia with a data segment size of 2048 bytes. Experimental results show that the average compression rate by WANProxy is 150.6, and the average network latency reduction rates by WANProxy are 95.2% for a 10 Mbps WAN environment and 60.7% for a 100 Mbps WAN environment, respectively. Compared with WANProxy, the two-stage compression of WANProxy and Zstandard increases the average compression rate by 33%. However, it increases the average network latency by 2.1% for a 10 Mbps WAN environment and 5.27% for a 100 Mbps WAN environment, respectively. Compared with WANProxy, our proposed method increases the average compression rate by 34.8% and reduces the average network latency by 13.8% for a 10 Mbps WAN and 12.9% for a 100 Mbps WAN, respectively. Performance analysis results of WANProxy show that its performance improvement in terms of network latency and WAN bandwidth is excellent in a 10Mbps or less WAN environment while superior in a 100 Mbps WAN environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.2083-2090
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• 2006

In an proposed Context-Aware SOA(Service Oriented Architecture) based OSGi(Open Service Gateway initiative) platform, Service provider manages relative kinds of services in an integrative basis from various sensors, puts each service in a SOAP (Simple Object access Protocol) message, and register thorn to the UDDI(Universal Description Discovery and Integration) server of service registry, service requester retrivel the specified kinds of services and call them to service provider. Recently most context-aware technologies for ubiquitous home network are mainly putting emphasis on RFID/USN and location-based technology. Because of this, service-oriented architecture researches have not been made enough. Under the environment of an OSGi service platform, various context-aware services are dynamically mapping from various sensors, new services are being offered for the asking of users, and existing services are changing. Accordingly, the data sharing between services provided, management of service life cycle, and the facilitation of service distribution are needed. Taking into considering all these factors, this study has suggested an Context-Aware SOA based eclipse SOA Tools Platform using OSGi platform that can transaction throughtput of more than 546 TPS of distributional Little's Law from ATAM(Architecture Tradeoff Analysis Method) while remaining stable other condition.

• KIISE Transactions on Computing Practices
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• v.21 no.10
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• pp.658-669
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• 2015

The paradigm of game development changes with technological trends. If the system can analyze and determine undefined inputs, users' input choices are not restricted. Therefore, game scenarios can have multifarious flows depending upon the user's input data. In this paper, we propose a method of including an output plan in the game system that is based on the user's input but is not restricted to predefined choices. We have implemented an experimental game on the Android platform by combining network communication and APIs. The game interface works as follows: first, the user's input data is transmitted to the server using HTTP protocol; then, the server carries out an analysis on the input data; and finally, the server returns the decision result to the game device. The game can provide users a scenario that corresponds to the decision results. In this paper, we used an image file for the user's input data format. The server calculates similarities between the user's image file and reference images obtained from the Naver Image Search API and then returns determination results. We have confirmed the value of integrating the game development framework with other computing technologies demonstrating the potential of the proposed methods for application to various future game interfaces.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.559-571
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• 2003

ENUM(tElephon NUmbering Mapping) is protocol that brings convergence between PSTN Networks and IP Networks using a unique worldwide E.164 telephone number as an identifier between different communication infrastructure. The mechanism provides a bridge between two completely different environments with E.164 number; IP based application services used in PSTN networks, and PSTN based application services used in IP networks. We propose a new way to organize and handle ENUM Tier 2 name servers to improve performance at the name resolution process in ENUM based application service. We build an ENUM based network model when NAPTR(Naming Authority PoinTeR) resource record is registered and managed by area code at the initial registration step. ENUM promises convenience and flexibility to both PSTN and IP users, yet there is no evidence how much patience is required when users decide to use ENUM instead of non-ENUM based applications. We have estimated ENUM response time, and proved how to improve performance up to 3 times when resources are managed by the proposed mechanism. The proposition of this thesis favorably influences users and helps to establish the policy for Tier 2 name server management.

• Pediatric Infection and Vaccine
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• v.22 no.3
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• pp.136-142
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• 2015

The Korean Society of Pediatric Infectious Diseases (KSPID) has participated in the task force team consisting of government authorities as well as civil medical experts and facilities to block the spread of Middle East Respiratory Syndrome in 2015. KSPID posted the "Middle East Respiratory Syndrome (MERS) Pop-up" in the homepage of The Korean Pediatric Society and The Korean Society of Pediatric Infectious Diseases. KSPID also released the "Guidelines for testing for MERS in children and adolescents" and the "Instructions for the Operation of National Safe Hospital" for children and adolescents in a timely manner. Such actions were aimed to prevent unnecessary anxieties, studies and isolation of pediatric patients with respiratory symptoms and signs caused by other common microbial etiologies as being suspected for MERS patients. This strategy relieved the doctors and parents from unnecessary fear and prevented the loss of unnecessary health care costs, and has proven to be a well-judged guideline and management protocol as evaluated after the final end of MERS outbreak. KSPID and its members should support the presence of pediatric infectious disease (PID) specialists in every medium size hospitals in Korea by developing the need for consultation fees for PID consultation in the hospital based practice and promoting the potential for cost savings related to prevention of health care associated infections and optimal prescription of antimicrobial agents. KSPID and its members need to approach and develop a communication plan to political decision makers to demonstrate and convince them of the importance of a PID specialist service.

• Journal of Korea Multimedia Society
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• v.12 no.8
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• pp.1109-1119
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• 2009

WLAN(Wireless Local Area Network) standard is currently developing with increased wireless internet demand. Though existing IEEE 802.11e demonstrates that data rates exceed 54Mbps with assuring QoS(Quality of Service), wireless internet users can't be satisfied with real communication system. After IEEE 802.11e system, Study trends of IEEE 802.11n show two aspects, enhanced system throughput using aggregation among packets in MAC (Medium Access Control) layer, and better data rates adapting MIMO(Multiple-Input Multiple-Output) in PHY(Physical) layer. But, no one demonstrates IEEE 802.11n system performance results considering MAC and PHY connection. Therefore, this paper adapts MIMO in PHY layer for IEEE 802.11n system based on A-MPDU(Aggregation-MAC Protocol Data Unit) method in MAC layer considering MAC and PHY connection. SVD(Singular Value Decomposition) method with WLAN MIMO TGn Channel is used to analyze MIMO. Consequently, Simulation results show enhanced throughput and data rates compared to existing system. Also, We use Ns-2(Network Simulator-2) considering MAC and PHY connection for reality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2293-2300
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• 2008

In ad-hoc sensor network, AODV routing information is disclosed to other nodes because AODV protocol doesn't have any security mechanisms. The problem of AODV is that an attacker can falsify the routing information in RREQ packet. If an attacker broadcasts the falsified packet, other nodes will update routing table based on the falsified one so that the path passing through the attacker itself can be considered as a shortest path. In this paper, we design the routing-information-spoofing attack such as falsifying source sequence number and hop count fields in RREQ packet. And we suggest an efficient scheme for detecting the attackers and isolating those nodes from the network without extra security modules. The proposed scheme doesn't employ cryptographic algorithm and authentication to reduce network overhead. We used NS-2 simulation to evaluate the network performance. And we analyzed the simulation results on three cases such as an existing normal AODV, AODV under the attack and proposed AODV. Simulation results using NS2 show that the AODV using proposed scheme can protect the routing-information-spoofing attack and the total n umber of received packets for destination node is almost same as the existing norm at AODV.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.1
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• pp.114-123
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• 2007

As a promising technology that enables ubiquitous computing and will lead the information technology industries of the next generation, the new field of sensor networks is one of the most active research topics today. From now on, each node, the network formation, and even the sensor network itself will interact with the generic network and evolve dynamically according to environmental changes, in a process of continual creation and extinction. In this paper, we propose a address-Internetworking scheme for interactive networking between a sensor network and the Internet based on the TCP port-numbers. The proposed scheme enables internetworking between a sensor network address scheme based on Zigbee and the Internet address scheme based on the Internet Protocol version 6 (IPv6). We implement the proposed address-Internetworking scheme using Berkeley TinyOS, Mica Motes, and IP. In addition we verify the proposed scheme by an interconnection experiment, which involves wireless sensor networks and the Internet, using IPv4/IPv6.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.1022-1025
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• 2009

USN(Ubiquitous Sensor Network) is a core infrastructure that makes come true the u-life in the ubiquitous society through various services of area such as u-city and u-Health. Therefore, we need to reseach about the domestic standards to establish the core technique of USN. Currently, the status of USN standards is most of technical standard and reseach that are technology for sensor node implementation and a protocol for energy-efficient communication and interlock with existing network. But, Standard and reseach for sensor network, integration management of heterogeneous sensor networks for USN application, sensing data management and USN database structure definition such as application and middleware are weak level. In this paper, we researched for standard development of the domestic sensor network service and relevant standard analysis to configure SWE(Sensor Web Enablement) of OGC(Open Geospatial Consortium) for standarded plattform technoloy in part of the middleware. Also we researched that it's a connection between domestic TTA (Telecommunications Technology Association) standards and SWE Standard. Finally, we researched for standard service plattform architecture on sensor network through analysis on the possibility of applying OGC-based services platform.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.2
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• pp.15-29
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• 2021

The signal intersection is the most challenging space for autonomous vehicles. To promote the safe driving of autonomous vehicles on urban roads with traffic signals, autonomous vehicles need to receive traffic signal information from infrastructure through V2I communication. Thus, a protocol for providing traffic signal information was added to the standard traffic signal controller specification of the National Police Agency. On the other hand, there are technical limitations when applying this to digital traffic signal controllers because the protocols are defined mainly for analog traffic signal controllers. Therefore, this study proposes developing a signal information linkage module to provide traffic signal information from a digital traffic signal controller to an autonomous vehicle and an algorithm improvement method that can provide accurate traffic signal information at the time of traffic signal transition.