• Journal of KIISE:Computer Systems and Theory
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• 제26권12호
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• pp.1539-1547
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• 1999

캐리-세이브 가산기 (CSA)는 회로 설계 과정에서 빠른 연산 수행을 위해 가장 널리 이용되는 연산기 중의 하나이다. 그러나, 현재까지 산업체에서 CSA를 이용한 설계는 설계자의 경험에 따른 수작업에 의존하고 있고 그 결과 최적의 회로를 만들기 위해 매우 많은 시간과 노력이 소비되고 있다. 이에 따라 최근 CSA를 기초로 하는 회로 합성 자동화 기법에 대한 연구의 필요성이 대두되고 있는 상황에서, 본 논문은 연산 속도를 최적화하는 효율적인 CSA 할당 알고리즘을 제안한다. 우리는 CSA 할당 문제를 2단계로 접근한다: (1) 연산식의 멀티 비트 입력들만을 고려하여 최소 수행 속도 (optimal-delay)의 CSA 트리를 할당한다; (2) (1)에서 구한 CSA 트리의 수행 속도 증가가 최소화 (minimal increase of delay) 되는 방향으로 CSA들의 캐리 입력 포트들에 나머지 싱글 비트 입력들을 배정한다. 실제 실험에서 우리의 제안된 알고리즘을 적용하여 연산식들의 회로 속도를 회로 면적의 증가 없이 상당한 수준까지 줄일 수 있었다.Abstract Carry-save-adder (CSA) is one of the most widely used implementations for fast arithmetics in industry. However, optimizing arithmetic circuits using CSAs is mostly carried out by the designer manually based on his/her design experience, which is a very time-consuming and error-prone task. To overcome this limitation, in this paper we propose an effective synthesis algorithm for solving the problem of finding an allocation of CSAs with a minimal timing for an arithmetic expression. Specifically, we propose a two step approach: (1) allocating a delay-optimal CSA tree for the multi-bit inputs of the arithmetic expression and (2) determining the assignment of the single-bit inputs to carry inputs of the CSAs which leads to a minimal increase of delay of the CSA tree obtained in step (1). For a number of arithmetic expressions, we found that our approach is very effective, reducing the timing of the circuits significantly without increasing the circuit area.

• Journal of KIISE:Information Networking
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• 제28권3호
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• pp.347-354
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• 2001

This paper proposes and analyzes an error control scheme which tries to recover the transmission error within the deadline of a message on FDDI networks. The error control procedure does not interfere other normal message transmissions by delivering retransmission request via asynchronous traffic as well as by delivering retarnsmitted message via overallocated bandwidth which is inevitably produced by the bandwidth allocation scheme for hard real-time guarantee. The receiver counts the number of tokens which it meets, determines the completion of message transmission, and finally sends error report. The analysis results along with simulation performed via SMPL show that the proposed scheme is able to enhance the deadline meet ratio of messages by overcoming the network errors. Using the proposed error control scheme, the hard real-time network can be built at cost lower than, but performacne comparable to the dual link network.

• Journal of the Korean Society of Marine Environment & Safety
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• 제19권1호
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• pp.85-92
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• 2013

Many efforts will have to be made on securing the stable supply of the energy due to the worldwide trend of controlling the utilization fossil fuels inducing global climate change. Renewable portfolio standard enforced to power companies over 500 MW capacity from 2012. Tidal current energy is one of the most interesting renewable and clean energy resources that have been less exploited. Especially, Korea has worldwide outstanding tidal current energy resources and it is highly required to develop a tidal current energy conversion system(TECS) in coastal region. So, we examine a tidal in-stream energy using a numerical model and estimate a tidal current potential for commercialization of tidal current power plant in the sea of the Bunamgun-do. Available tidal energy resources is also analytically estimated using a tidal farm method and the annual energy production of an optimal TECS arrays will be calculated with taking into account interference of lateral and longitudinal spacing.

• Journal of the Institute of Electronics Engineers of Korea TC
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• 제38권8호
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• pp.19-29
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• 2001

The recent explosion in the Internet applications, Internet. host number and the traffic in the IP backbone network is posing new challenges for transport network. This requires a high-speed IP backbone network that has a substantially higher bandwidth than the one offered by current networks, which prompts the development of all-optical network. To obtain optical network utilization gains, we need a software which establishs logical topology to make possible the efficient use or physical topology, and control the optical network in combination with the IP layer routing protocols. Finally, the logical topology is required higher efficient than physical topology. For this an efficient algorithm for the routing and wavelength assignment(RWA) in the WDM all-optical network is necessary. In this paper, two kinds of heuristic algorithms to establish logical topology for WDM networks and arc applied to the design of logical topology of domestic backbone network. These algorithms are found to work quite well and they arc compared with each other in terms of blocking rate, etc.

• Journal of the Korea Society for Simulation
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• 제28권3호
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• pp.25-40
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• 2019

Today, container terminals are fiercely competing to attract an increasing number of containers. As a way to improve terminal productivity, this study proposes two dispatching rules for yard truck allocation priorities. First, Multi-Attribute Dispatching Rule(MADR) is an allocation method to calculate the weighted sum of multiple factors affecting container terminal productivity and priority them. Especially, the workload of the quay crane was considered one of the factors to reduce the residence time of the ship. Second, Cycling Dispatching Rule(CDR) is the effective way to increase the number of double cycles that directly affect terminal productivity. To identify the effects of combinations of pooling and dispatching, a comparative experiments was performed on 8 scenarios that combined them. A simulation environment has been developed for experiments and the results have demonstrated that the combination of terminal level pooling and Multi-attribute Dispatching could be an excellent combination in KPIs consisting of GCR and delayed departure of ships, etc.

• Journal of Korea Port Economic Association
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• 제30권3호
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• pp.39-58
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• 2014

Korea and China have maintained sea routes between two nations through the shipping conference which was established in May 1993. Due to this effort, the market of Korea-China car ferry on Yellow sea makes growth year by year. The car ferry business has shown fierce competition because it has huge impacts on regional and national level economy. In this respect, the aim of this research is to analyze the structural analysis for ports of Korea-China car ferry using Shift Effect(SE) method. As a results, passengers and cargo volumes of Incheon port continuously transfer to Pyeontaek and Gunsan port. Moreover, absolute growth rate of Incheon port do not reach the potential growth rate. The competitiveness power of Incheon port has lower position compared to Pyeontaek and Gunsan port. The cargo volumes of ports located on western coast of Korea have increased recently, however, passengers and cargo volumes of Incheon port have shown lower increasing rate compared to average of Korean western coast ports. For Incheon port, high value added cargoes which give large profit on port side, have to be attracted. Moreover, Incheon port has to become a specialized port.

• The Journal of the Convergence on Culture Technology
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• 제9권5호
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• pp.613-618
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• 2023

The advancement of Information and Communication Technology (ICT) is accelerating innovation across society, and the defense sector is no exception as it adopts technologies aligned with the Fourth Industrial Revolution. In particular, the Army is making efforts to establish an advanced Army TIGER 4.0 system, aiming to create highly intelligent and interconnected mobile units. To achieve this, the Army is integrating cutting-edge scientific and technological advancements from the Fourth Industrial Revolution to enhance mobility, networking, and intelligence. However, the existing addressing system, IPv4, has limitations in meeting the exponentially increasing demands for network IP addresses. Consequently, the military considers IPv6 address allocation as an essential process to ensure efficient network management and address space provisioning. This study proposes an approach for IPv6 address allocation for the future military, considering the Army TIGER system. The proposal outlines how the application networks of the Army can be differentiated, and IP addresses can be allocated to future unit structures of the Army, Navy, and Air Force, from the Ministry of National Defense and the Joint Chiefs of Staff. Through this approach, the Army's advanced ground combat system, Army TIGER 4.0, is expected to operate more efficiently in network environments, enhancing overall information exchange and mobility for the future military.

• Journal of Agricultural Extension & Community Development
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• 제19권4호
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• pp.1041-1066
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• 2012

This article aims to analyse the change factor of the industry in rural area. As the regional economy is consist of variety industry in local Revitalization of Rural Economy should consider the growth factor of industry. Analytical method is Shift-Share analysis, analysis data is used GRDP of the 5 target area. Analysis is showed that Agriculture, forestry and fishing is leading position. but Farm population decreased rapidly underway. Side work farmer and industry population is increasing rapidly. the Regional Economic growth inhibitory of 5 Gun is the weakness of the internal factor. especially Competition component is than industry-Mixed component. and the Growth of Agriculture, forestry and fishing is external factor. To improve the regional economy, 5 Gun must improve the fault. and the growth of Agriculture, forestry and fishing should promote the consumption of local products to as the local food system.

• 월간낙농육우
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• 제36권1호
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• pp.126-136
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• 2016

세계 최대의 원유생산을 자랑하는 유럽의 낙농산업이 갈림길에 섰다. 지난 30년간 지탱해 온 유럽연합(EU) 국가별 우유 생산량 할당제(쿼터제)가 '15년 4월부터 폐지되면서 전환기를 맞이했다. 우유 생산량 제한정책의 폐지를 맞아 유럽의 낙농업계에는 희비가 갈리고 있다. EU는 세계 낙농시장에서 주요 역할을 하고 있으며 치즈 등 많은 낙농제품을 수출하는 선진 수출국으로 EU 유제품 수급 동향이 국제가격에도 영향을 미치고 있어 전세계 낙농종사자의 이목이 집중되고 있다. 유럽의 선진 낙농국들을 중심으로 쿼터 폐지에 따른 생산량 증가를 해소하기 위해 해외 시장 개척에 집중하는 등 국가별로 쿼터제 폐지라는 거대한 산을 넘기 위해 제 각기의 노력을 펼치고 있다. 우리나라 낙농업 또한 EU 수급 상황의 영향권에 있기 때문에 이들의 움직임을 주목할 필요가 있다. 네덜란드는 국가경제에서 중요한 위치를 차지하고 있는 낙농업의 지속가능한 성장을 위해 단기적인 성장이 아닌 중장기적인 관점으로 환경문제에 적극 대응하고 있다. 역사와 전통이 갚은 치즈의 대표 본고장 스위스는 쿼터제 폐지로 낮은 가격의 원유가 범람하면서 위기를 맞은 가운데 이를 타개하기 위한 방안 마련에 초점을 맞추고 있다. EU 내에서도 많은 원유를 생산해 내고 있는 독일 낙농업계도 운영비용을 절감할 수 있는 낙농 장비로 교체하는 등 생산비 절감 방안 마련에 집중하고 있다. 여성낙농인들과 함께 작지만 강한 나라 네덜란드와, 역사와 전통을 지난 스위스, 기술집약적 낙농 강국 독일을 방문해 그들이 낙농 강국으로 성장할 수 있었던 주요 성공요인과 사례를 중심으로 둘러보고 앞으로 우리나라 낙농이 나아갈 방향을 가늠해본다.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2006년도 학술대회 1부
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• pp.593-598
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• 2006

웨어러블 컴퓨팅 환경에서 사용 가능한 키보드는 부담 없이 착용할 수 있어야 하며 충분히 빠른 속도로 문자를 입력할 수 있어야 한다. 또한 일반적인 사용자도 특별한 훈련과정 없이 쉽게 사용할 수 있어야 한다. 상용화된 웨어러블 컴퓨팅용 입력장치는 주로 소형화 QWERTY 키보드인데 공통적으로 키 수를 줄이는 방식을 택하고 있다. 그러나 줄이는 키 수에 대응하여 문자 입력을 위한 키 입력 수(KSPC: Key Strokes per Character)가 증가하기 때문에 입력효율이 저하되고 학습을 위한 요구되는 노력이 또한 증가한다. 그럼에도 불구하고 Halfkeyboard, WristPC keyboard, FrogPad 등 상품화된 키보드는 충분히 작은 사이즈가 아니어서 일상적으로 부담 없이 수용하기에는 물의가 있다. 본 연구는 이런 문제점을 해결하기 위해 키 간격을 줄여 극적으로 키보드를 소형화할 수 있는 원키 키보드라는 개념을 제안하였다. 전통적인 키보드의 경우 하나의 키에 하나의 문자가 할당되는데 반해 원키 키보드는 하나의 키 판 위에 10*5 배열의 QWERTY 키보드 문자배열을 표시하게 하였다. 또한 표시된 문자판에서 어떤 것을 선택하여 눌렀는지 손가락의 위치를 센싱하여 해당 문자를 입력하도록 하였다. 70mm*35mm 크기의 원키 키보드에 대한 실험결과 착용성과 사회적 수용성이 우수하였으며 5 세션의 시도를 통해 평균 18.9WPM 의 입력속도와 교정되지 않은 순수 에러율 0.87%를 기록하였다.