• Journal of information and communication convergence engineering
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• v.10 no.3
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• pp.237-241
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• 2012

In wireless sensor networks, the importance of transporting data correctly with reliability is increasing gradually along with the need to support communications between the nodes and sink. Data flow from the sink to the nodes requires reliability for control or management that is very sensitive and intolerant of error; however, data flow from the nodes to the sink is relatively tolerant. In this paper, with emphasis on the data flow from the sink to the nodes, we propose a mechanism that considers accurate transport with reliability hop-by-hop. During the process of sending the data, if errors occur or data is missing, the proposed mechanism supports error recovery using a fixed window with selective acknowledgment. In addition, this mechanism supports congestion control depending on the buffer condition. Through the simulation, we show that this mechanism is accurate, reliable, and proper for transport in wireless sensor networks.

• The KIPS Transactions:PartC
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• v.8C no.3
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• pp.345-350
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• 2001

IP 네트워크 상에 TCP 데이터 트래픽의 제공은 처리율과 공정성을 향상시키기 위해 특별한 기법이 필요하다. 여기에는 DT와 RED와 같은 많은 기법들이 제안되었다. RED 알고리즘은 폭주를 회피하고 적은 지연과 높은 처리율을 유지하기 위한 목적으로 제안되었다. 현재의 TCP/IP 환경에서 TCP 근원지는 Slow-Start 단계에 들어감으로써 드롭된 패킷에 반응하지만, 네트워크 이용률은 급속히 떨어진다. 폭주를 탐지하고, 이를 무작위로 선택된 연결에 통보하므로써 RED는 글로벌 동기화 및 공정성 문제를 유발한다. 본 논문에서는 성능을 향상시키기 위해 공정성을 유지하고, 글로벌 동기화 문제를 해결할 수 있는 능동적인 큐 관리 알고리즘을 제안한다. 제안된 알고리즘은 버퍼크기와 임계치 변화에 따른 goodput, 처리율, 공정성의 평가인자를 이용하여 기존의 기법인 DT, RED와 비교 분석을 수행하고, 제안된 기법의 타당성을 보인다.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.444-446
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• 2003

This paper deals with an allocation strategy for the resources of direct load control program, which is considered the operating states in power systems. The existing approaches, load shedding priority algorithm, curtailment payback based algorithm and mixed curtailment algorithm, are based on the uniform allocation strategy. These approaches are not taken into account the operating states in power systems. So, under the critical operating condition, direct load control resource is evaluated by introducing the congestion factor.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.241-245
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• 1998

본 논문에서는 이동호스트에게 멀티미디어 데이터 전송 시 고려되어야 할 주요 특징과 문제점을 검토하고 이때 발생하는 문제점을 해결하기 위해 Mobile-IP환경에서 네트워크 링크의 공유에 의해 자원을 효율적으로 사용할 수 있는 멀티캐스트 방법을 기반으로 하고 이러한 멀티캐스트를 위한 인터넷 라우팅 프로토콜로는 링크-상태(link-state)알고리즘을 기반으로 하는 MOSPF(Multicast Open Shortest Path First)를 이용한다. 또한 인터넷상에서 라우터들이 멀티캐스트 그룹에 속하는 호스트들을 추적하기 위한 방법으로 IGMP(Internet Group Management Protocol)을 제안 사용하였다. 기존에 제안되어 사용되어지고 있는 UDP/IP based multicast를 사용할 경우에 패킷손실이나 전송지연 등을 위한 어떠한 성능도 보장받지 못하고 많은 대역폭이 요구되는 실시간 패킷들은 중계기의 트래픽 폭주(congestion) 현상에 의해 손실될 가능성이 높다. 이를 해결하기 위한 방안으로 실시간 데이터 전송 및 QOS를 제공하기 위해 RTP/RTCP 프로토콜을 접목시키는 방식을 기술하였다.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.131-140
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• 2005

Heart failure is a clinical syndrome comprised of a number of symptoms and signs associated with congestion and/or hypoperfusion. Specific pharmacologic therapies have been developed to slow disease progression from early to more advanced stages. Once symptoms have developed, aggressive multimodality interventions are instituted to alleviate symptoms and improve clinical status and quality of life; especially in those patients that present symptoms. Recently, an evolving adjunctive therapeutic modality, that involves using implanted electrical devices: cardiac resynchronization with or without implantable cardioverter defibrillators (ICD). has been used for management. Cardiac resynchronization therapy (CRT) is a proven treatment for selected patients with heart failure-induced conduction disturbances and ventricular dyssynchrony. When used in combination with stable, optimal medical therapy, CRT is designed to reduce symptoms and improve cardiac function by restoring the mechanical sequence of ventricular activation and contraction. This review summarizes the rationale, procedure, clinical trials, and clinical indications for CRT.

• Journal of information and communication convergence engineering
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• v.21 no.4
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• pp.329-336
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• 2023

This paper introduces an edge AI-based scene-specific object detection system for long-term traffic management, focusing on analyzing congestion and movement via cameras. It aims to balance fast processing and accuracy in traffic flow data analysis using edge computing. We adapt the YOLOv5 model, with four heads, to a scene-specific model that utilizes the fixed camera's scene-specific properties. This model selectively detects objects based on scale by blocking nodes, ensuring only objects of certain sizes are identified. A decision module then selects the most suitable object detector for each scene, enhancing inference speed without significant accuracy loss, as demonstrated in our experiments.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.782-787
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• 2004

Internet Engineering Task Force (IETF) has been considering the deployment of the Random Early Detection (RED) in order to avoid the increasing of packet loss rates which caused by an exponential increase in network traffic and buffer overflow. Although RED mechanism can prevent buffer overflow and hence reduce an average values of packet loss rates, but this technique is ineffective in preventing the consecutive drop in the high traffic condition. Moreover, it increases a probability and average number of consecutive dropped packet in the low traffic condition (named as "uncritical condition"). RED mechanism effects to TCP congestion control that build up the consecutive of the unnecessary transmission rate reducing; lead to low utilization on the link and consequently degrade the network performance. To overcome these problems, we have proposed a new mechanism, named as Extended Drop slope RED (ExRED) mechanism, by modifying the traditional RED. The numerical and simulation results show that our proposed mechanism reduces a drop probability in the uncritical condition.

• Journal of the Korean Society of Costume
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• v.64 no.3
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• pp.47-61
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• 2014

Dongdaemun Fashion District has been successfully positioned as the main hub for fashion product distribution in Korea since 1960 thanks to its unique and successful fashion merchandising system. This system enables the distributors to respond quickly to consumer need and inexpensive price. However, at the present time, Dongdaemun Fashion District has been facing serious challenges from new types of retail stores such as fast fashion brands like ZARA and online shopping malls. To achieve this result, statistical analysis was performed using data from 68 employees of wholesalers in the Dongdaemun Fashion District. They were required to answer questions regarding the marketing system supporting program, amenities like restrooms, and traffic congestion. For the case study, C.I.S, a successful global wholesale system in Italy, was selected. C.I.S has 130 offices offering professional services in the field of trade, legal and tax issues, and insurance. This study suggests cooperation among related wholesalers in order to make an area management plan in the Dongdaemun Fashion District. Also, for the wholesalers to build up product information system and infrastructure for the Global marketing strategy.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.648-653
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• 2006

It pollute the earth environment with systematic industrialization. Also the congestion of cities that ignore ecosystem threaten habitation environment of human. For ESSD make progress to many researches internal and external. However we don't develop model for internal environment, research evaluation of ecological polis for this. The present research put in operation that make up question experts. In the event many people know necessity of ecological development. But It point out reality with many phases. One side we need to educate, publicize about environment. make good model and cultivate process.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.4
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• pp.127-134
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• 2013

While there are many services that can check current traffic condition and application program such as bus arrival alarm are developed, since it only provide simple alarm and check level of information, it is still insufficient in many senses. Therefore, the program that try to develop in this study is the system that predict arrival time to destination and inform the bus passengers by applying real time traffic information. The system developed related to this study is still very inadequate. In the system developed in this thesis, when the user input the current bus number and destination using smart-phone, relevant server acquire the bus route information from bus information DB, and analyze real time traffic information based on the information from traffic information DB, and inform customer of expected arrival time to destination. In this thesis, traffic congestion can be eased off and regular operation of public transportation can be improved with reliable destination arrival alarm. Also, it is considered that pattern of bus users can be analyzed by using these information, and analyzing average transport speed and time of public transportation, travel time depending on various situation can give a boost to study related to transportation information and its development.