• Journal of Information Processing Systems
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• v.7 no.1
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• pp.29-42
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• 2011

Wireless sensor networks are composed of a large number of sensor nodes with limited energy resources. One critical issue in wireless sensor networks is how to gather sensed information in an energy efficient way, since their energy is limited. The clustering algorithm is a technique used to reduce energy consumption. It can improve the scalability and lifetime of wireless sensor networks. In this paper, we introduce a clustering protocol with mode selection (CPMS) for wireless sensor networks. Our scheme improves the performance of BCDCP (Base Station Controlled Dynamic Clustering Protocol) and BIDRP (Base Station Initiated Dynamic Routing Protocol) routing protocol. In CPMS, the base station constructs clusters and makes the head node with the highest residual energy send data to the base station. Furthermore, we can save the energy of head nodes by using the modes selection method. The simulation results show that CPMS achieves longer lifetime and more data message transmissions than current important clustering protocols in wireless sensor networks.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.119-125
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• 1998

In recent years there has been a huge increase in demand for new various communication services due to the rapid advances in wireless communication. These new emerging services give rise to the interference with the existed radio system. As the new representative systems NGSO/MSS systems have been developed, using NGSO, especially Low Earth Orbit (LEO), satellites such as Iridium, Globalstar systems to provide the rapid transfer of information and the positioning services for the moving persons whenever they want to communicate, even if wherever they are. In this paper we have analysed on the interference between the feeder link of NGSO/MSS and M/W fixed system, that is the interference from the mobile satellite earth station into M/W station, as well as the interference from M/W station into the mobile satellite earth station, and the coordinated area.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.271-276
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• 2000

A railway station forecourt is the first place in a city that may make an impression on first time visitors. Their first impression is influenced by the view of the city from the station. This study had two objectives: one was to clarify the evaluation structure of a station forecourt landscape and the other was to clarify the effect of landscape elements on public preference using multivariate analysis, and to discuss the problems of designing a station forecourt. In order to accomplish these objectives, psychological experiments based on photos of station forecourts were carried out, and the relationship between public preference and landscape elements was analyzed. A significant relationship between public preference and elements of a station forecourt landscape was quantitatively observed and several problems inherent to station forecourt design were identified.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1123-1140
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• 2019

Many Internet of Things (IoT) applications involving bursty traffic have emerged recently with event detection. A power management scheme qualified for uplink bursty traffic (PM-UBT) is proposed by distinguishing between bursty and general uplink traffic patterns in the IEEE 802.11 standard to balance energy consumption and uplink latency, especially for stations with limited power and constrained buffer size. The proposed PM-UBT allows a station to transmit an uplink bursty frame immediately regardless of the state. Only when the sleep timer expires can the station send uplink general traffic and receive all downlink frames from the access point. The optimization problem (OP) for PM-UBT is power consumption minimization under a constrained buffer size at the station. This OP can be solved effectively by the bisection method, which demonstrates a performance similar to that of exhaustive search but with less computational complexity. Simulation results show that when the frame arrival rate in a station is between 5 and 100 frame/second, PM-UBT can save approximately 5 mW to 30 mW of power compared with an existing power management scheme. Therefore, the proposed power management strategy can be used efficiently for delay-intolerant uplink traffic in event-driven IoT applications, such as health status monitoring and environmental surveillance.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.216-219
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• 1998

이 논문에서는 IMT-2000(International Moblie Telecommunication-2000)시스템에서의 멀티미디어 트래픽을 전송하기 위한 핸드오프 처리절차를 제안하였다. 이 절차에는 기본 코드채널(Fundamental Code Channel)과 부가 채널(Supplemental Code Channel)을 제어하기 위한 핸드오프관련 메시지들이 포함되었다. 부가 채널코들를 사용하기 위한 협상은 전송되는 트래픽의 크기에 따라 핸드오프 초기화 동안 수행된다. 그리고 MS(Moblie Station), BTS(Base Station transceiver Subsystem) 및 BSC(Base Station Controller)사이에서의 핸드오프 처리를 위한 호 흐름도와 상태천이도 (State Transition Diagram)도 설계하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.8
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• pp.924-927
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• 2016

In this paper, we consider a cumulative distribution function (CDF)-based opportunistic scheduling for downlink transmission in a cellular network consisting of a base station and multiple mobile stations. We present a closed-form formula for the average starvation period of each mobile station (i.e., the length of the time interval between two successive scheduling points of a mobile station) over Markov time-varying channels. Based on our formula, we investigate the starvation period of the CDF-based scheduling for various system parameters.

• The Transactions of the Korea Information Processing Society
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• v.5 no.7
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• pp.1813-1828
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• 1998

본 논문에서는 기능별로 태스크를 설계하고 프로세스간 통신을 위하여 공유 메모리를 사용하여 wet station 모니터링 시스템을 구현한다. 롯트라는 반도체 웨이퍼 단위를 처리하기 위하여 레시피 명령을 설계하고 이 레시피에 의한 롯트의 배치 처리 과정을 모니터링하는 방법에 대하여 논한다. 설계된 태스크 및 레시피, 공유 메모리를 구현하여 실제 장비에 적용한 결과 각 태스크들이 레시피 명령에 따라 공유 메모리를 매개로 하여 배치 작업을 진행하였고 그 과정을 그래픽 화면을 통해 시각적으로 모니터링 할 수 있었다.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.4
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• pp.137-146
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• 1993

We consider single server feedback queueing systems with priorities. In the model, there are J stations and job classes. Jobs of class i arrive at station i according to a Poisson process, and have a general service time distribution. We derive the generating functions of the number of jobs at each station just after a busy period and the formula for the mean sojourn time that a specific tagged job spends at station j from its arrival to departure from the system.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.493-495
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• 2004

본 논문은 도시계획과정에서 도시설계안을 행정가, 설계자, 지주, 인근거주자 등에게 제시하고 이들의 요구사항을 실시간으로 반영할 수 있는 도시설계를 위한 가상현실 협업시스템인 AR-Station을 소개한다. 본 시스템은 다양한 참여자들 간의 원활한 의사소통과 협업을 위하여 가상 도시 모델을 시각화하기 위한 Hybrid Scene Graph와 직관적인 인터랙션을 제공하기 위한 탠저블 인터페이스를 사용한다. 참여자들의 작업공간은 시스템과 참여자들 사에의 상호작용이 효율적으로 이루어지도록 반영공간과 인터랙션공간으로 구분하여 설계하고 구현하였다.

• Journal of Embryo Transfer
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• v.28 no.2
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• pp.79-85
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• 2013

The recent development in genetic assisted selection (combining traditional- and genome assisted selection method) and reproduction technologies will allow multiplying elite cow in Hanwoo small farm. This review describes the new context and corresponding needs for genome assisted selection schemes and how reproductive technologies can be incorporated to get more genetic gain for cow genetic improvement in Hanwoo. New improved massive phenotypes and pedigree information are being generated from commercial farm sector and these are allowing to do genetic evaluation using BLUP to get elite cows in Korea. Moreover cattle genome information can now be incorporated into breeding program. In this context, this review will discuss about combining the reproductive techniques (Multiple Ovulation Embryo Transfer; MOET) and genome assisted selection method to get more genetic gain in Hanwoo breeding program. Finally, how these technologies can be used for multiplication of elite cow in small farm was discussed.