• 전기전자학회논문지
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• 제3권1호
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• pp.150-160
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• 1999

본 논문에서는 기존의 레지스터 전송 단계 합성기들이 가지고 있는 단점을 개선하는 새로운 레지스터 전송 단계 합성 방법을 제안한다. 기존의 레지스터 전송 단계 합성기들은, 하드웨어 기술 언어로 기술된 설계 사양을 순서회로로 변환하는 과정에서 불합리한 변환을 수행하고 순서 회로를 최적화 하는 과정에서 순서회로를 구성하는 레지스터와 조합회로를 분리하여 조합회로부만을 최적화 한다. 본 논문에서는 이러한 방식의 레지스터 전송 단계 합성기들이 가지는 단점을 지적하고, 이런 단점을 극복하기 위한 새로운 레지스터 전송 단계 합성 방법을 제안한다. 또한, 제안된 방법을 감시용 시스템의 콘트롤러 설계 및 8 비트 부호화 곱셈기에 적용한 결과를 제시함으로써 본 논문에서 제안하는 방법의 유용성을 입증한다.

• Journal of Information Processing Systems
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• 제12권1호
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• pp.57-72
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• 2016

To provide effective communication in the wireless mesh network (WMN), several algorithms have been proposed. Since the possibilities of numerous failures always exist during communication, resiliency has been proven to be an important aspect for WMN to recover from these failures. In general, resiliency is the diligence of the reliability and availability in network. Several types of resiliency based routing algorithms have been proposed (i.e., Resilient Multicast, ROMER, etc.). Resilient Multicast establishes a two-node disjoint path and ROMER uses a credit-based approach to provide resiliency in the network. However, these proposed approaches have some disadvantages in terms of network throughput and network congestion. Previously, the buffer based routing (BBR) approach has been proposed to overcome these disadvantages. We proved earlier that BBR is more efficient in regards to w.r.t throughput, network performance, and reliability. In this paper, we consider the node/link failure issues and analogous performance of BBR. For these items we have proposed a resilient packet transmission (RPT) algorithm as a remedy for BBR during these types of failures. We also share the comparative performance analysis of previous approaches as compared to our proposed approach. Network throughput, network congestion, and resiliency against node/link failure are particular performance metrics that are examined over different sized WMNs.

• 센서학회지
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• 제26권1호
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• pp.66-72
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• 2017

The three dimensional ultrasonic anemometer was constructed to reduce the disadvantages of the two-dimensional anemometer and to be free from the use environment. Three pairs of transmitting and receiving ultrasonic sensors were designed to face each other at an angle of $45^{\circ}$ to the upper and lower surfaces at intervals of $120^{\circ}$. 200 kHz ultrasonic sensor Oscillation, transmission and reception, level detection, power supply circuit were designed and U, V, W wind speed vector components were obtained by measuring the time of first received ultrasonic pulse by transmitting pulse ultrasound. It is implemented as firmware in ARM Coretex-M3 processor so that horizontal and vertical wind direction and wind speed can be converted into digital signal by vector calculation. In this study, The three-dimensional ultrasonic anemometer can complement the disadvantages of the two-dimensional anemometer (mechanical and ultrasonic), and it is expected to gradually replace the two-dimensional anemometer due to its high utilization rate by collecting additional information such as vertical wind.

• 한국유기농업학회지
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• 제2권1호
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• pp.16-23
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• 1993

The traditional farming method has very long history in the process of agricultural development. The application of chemical fertilizers production became most popular to increase quantities of agricultural production. The United States of America is one of largest countries in the world. There are at present 50 States and farming conditions are very different from each individual States. There are increasing trend of agricultural production by applying chemical fertilizers as well as sprays during last 50 years(1940-90). The disadvantages of conventional farming method were to destroy nature and human life. There were some other kinds of disadvantages such as nitriated contamination in drinking water both for human being and animals. The alternative farming method is one of new farming method reducing and/of non-application of chemical fertilizers and sprays in agricultural production. There is less economic research on alternative farming system about $5.444 economic advatages in organic farms comparing commercial farms at the same area. There are advantage of higher unit price level in orgnic products, decreasing chemical costs as well as effect of crop combinations. It is certainly necessary to have more empirical research on economic and management of alternative farming method in the United States of America. However, if there is economic advantage in alternative farming methods, the future development possibility of alternative farming method can be very bright in vear future. There might be more advantages such as soil conservation, better quality of agricultural products, better health conditions of farmer's and consumer's as well as keeping healthy environment of rural and urban areas.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권2호
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• pp.174-181
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• 2007

Today, endoscopic procedures are common in diagnostic and other surgical procedures, with endoscopically enhanced and magnified images permitting surgical access through minimal incisions. This has expanded the treatment options for many difficult anatomic sites, and the endoscope facilitated safe anatomic reduction and fixation. The use of the endoscope may reduce the disadvantages of open fracture repair and should be considered for broad application in the treatment of displaced facial bone fractures. Optical endoscopic magnification minimizes the disadvantages associated with open surgical repair, including the risk of facial nerve injury and external facial scarring, and no postoperative complications have been attributable to the endoscopic approach. This technique was used in 14 patients treated at Ulsan University Hospital, Korea, from September 2004 to August 2006, including six mandibular subcondyle fractures, five blowout fractures and three zygomaticomaxillary complex (ZMC) fractures. Careful preoperative evaluation and proper surgical technique were essential to achieve optimal results in the selected patients.

• 정보관리학회지
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• 제15권3호
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• pp.73-93
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• 1998

본 연구는 문헌의 내용구조와 이용자의 정보요구는 밀접한 관련성이 있기 때문에 문헌의 본문을 내용 단위구조로 분할하여 색인한다면 기존의 전문데이터베이스 구축방식에 비해 검색효율을 향상시킬 수 있다는 가설을 설정하고 이를 검증하는데 목적이 있다. 이 가설을 검증하기 위하여 먼저 학술논문의 내용구조 모델을 설정하고, 이 모델을 기반으로 컴퓨터 관련분야 70여편의 학술논문을 대상으로 실험용 전문데이터베이스를 구축한 다음, 이에 대한 검색효율을 측정하여 내용구조 기반 전문검색시스템의 성능을 실험적으로 평가하였다.

• Steel and Composite Structures
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• 제36권2호
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• pp.197-211
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• 2020

Application of the steel ring as a type of seismic fuse has been one of the efforts made by researchers in recent years aiming to enhance the ductility of the bracing systems which in turn, possesses various advantages and disadvantages. Accordingly, to alleviate these disadvantages, an innovative bracing system with a diamond scheme equipped with a steel ring is introduced in this paper. In this system, the braces and yielding circular damper act in parallel whose main functionality is to increase ductility, energy absorption and mitigate drawbacks of the existing bracing systems, in which the braces and yielding circular damper act in parallel. To conduct the experimental tests, specimens with three types of rigid, semi-rigid and pinned connections were built and subjected to cyclic loading so that their performance could be analyzed. Promisingly, the results indicate both great applicability and efficiency of the proposed system in energy absorption and ductility. Moreover, it was concluded that as the braces and damper are in parallel, the use of a steel ring with smaller size and thickness would result in higher energy absorption and load-resisting capacity when compared to the other existing systems. Finally, to assess the potential of numerically modeling the proposed system, its finite element model was simulated by ABAQUS software and observed that there is a great agreement between the numerical and experimental results.

• 정보관리학회지
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• 제26권3호
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• pp.335-353
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• 2009

RFID 시스템이 1990년대 말에 처음으로 도서관에 도입된 이래, 13.56MHz 주파수를 활용하는 HF 시스템과 900MHz 주파수를 활용하는 UHF 시스템에 대한 논란도 계속하여 확대되고 있다. 이에 본 연구에서는 HF RFID 시스템과 UHF RFID 시스템의 특징을 분석하고, 도서관 현장에서 적용되는 실제 상황에서의 장단점을 규명하고자 하였다. 이를 위해 국내 도서관의 RFID 시스템 도입현황과 국내의 대표적인 4개의 도서관 RFID 시스템의 도입사례(HF, UHF 각각 2개 도서관)를 분석하였다. 또한 HF RFID 시스템과 UHF RFID 시스템의 기능적 특징, ISO/DIS 28560에서의 주파수 논의, 각 시스템의 공급자 및 사용자 의견도 조사되었다.

• 지식경영연구
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• 제17권2호
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• pp.205-229
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• 2016

Owing to the current economic downturn, one of the most important goals of the organizations who are actively involved in Information Technology Outsourcing (ITO) is the cost efficiency. We focus on supplier firm's domain understanding to make the cost efficiency; therefore, we examine how the disadvantages from lower domain knowledges affect outsourcing performance moderated by outsourcing ratio and knowledge change environments. That is, if clients can endure disadvantage from service providers' lower domain knowledge, they can achieve cost efficiency by choosing lower domain knowledge suppliers with less expensive cost. To examine performance gap depending on the environments, we applied 'A Learning Model of IT Outsourcing' which is suggested by previous literature. As a result, we suggest five strategies for clients to contract with suppliers which have lower domain knowledge: (1) Prepare the strategy to endure disadvantages from the early stage. (2) Make the strategy depending on outsourcing ratio. (3) Knowledge transfer between organizations is important. (4) Make a short-term contract if they do not have good environments for organizational learning. (5) Client's knowledge change environments are more important than those of supplier's. Finally, we offer various implications for clients and suppliers in IT outsourcing.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.663-664
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• 2018

근 100년간 자동차 디자인은 많은 변화가 있었지만 사이드 미러는 변하지 않았다. 이는 4차 산업 혁명이라는 시대에 뒤떨어진 고착상태이며 많은 단점을 가지고 있는 아날로그 방식이다. 이에 따라 사이드 미러를 카메라로 대체함으로써 디지털 방식으로 바꾸고 '거울'이 가지는 한계성 및 단점들을 개선하였다. 또한 연 5~10%의 연비 절감, 위협 자동 감지 등의 추가적인 여러 이점을 얻을 수 있다. 이 프로젝트에서는 호환성이 뛰어난 라즈베리파이를 메인보드로 사용하고 적외선 거리 센서, 모니터 모듈을 연결하여 상황별 자동 위협감지 및 사고 예방에 초점을 두었다.