• 한국멀티미디어학회논문지
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• 제13권10호
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• pp.1534-1546
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• 2010

센서 네트워크에서는 에너지 소비를 줄이기 위해 다양한 계층적 클러스터링 방법이 제안되었다. 그러나 대부분의 연구에서 나타나는 문제점은 노드의 실제 배치를 생각하지 않고 일방적인 그리드 형태의 구조 또는 무작위 적인 클러스터 구조를 구성하는 것이다. 이렇게 구성된 클러스터는 클러스터의 크기와 포함된 노드의 수가 불균형하기 때문에 큰 에너지 효율을 보이기 힘들다. 그래서 본 논문에서는 실제 노드들이 배치가 된 후 R-Tree의 노드 분할 및 병합 알고리즘에 착안하여 보다 더 효율적인 클러스터를 구성할 수 있는 방법인 CSM(Clustering using Split & Merge algorithm)을 제안한다. 다양한 실험결과 CSM은 기존 방법보다 에너지 효율적인 클러스터링을 생성함으로써 최대 1.6배의 에너지 효율을 보였다.

• 한국자동차공학회논문집
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• 제5권2호
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• pp.162-172
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• 1997

We investigated passby noise measurement method in a small-sized semi-anechoic chamber satisfying the American based SAE J1470 Recommended Practice to facilitate the measurements. We have tired two passby noise prediction methods. One is line array microphone method in which the free space sound field is decomposed into its eigenfunctions in the spherical coordinates and rearranged according to the order of the spherical Hankel function. However, due to the characteristics of the spherical Hankel function, it is impossible to distinguish the function's characteristics according to the order in farfield. Consequently it can be applied in the transient region of the nearfield and the farfield. The other method is nearfield acoustic holography(NAH). Although measuring hologram for the several operational engine speeds by conventional scanning method is time-consuming work, we can greatly reduce the measuring time by selecting the appropriate engine speed through preexperimental knowledge. To verify this method we experimented with the outdoor passby noise measurements and the passby noise prediction in the small-sized semi-anechoic chamber for the identical passenger vehicle and obtained reasonable and acceptable results.

• Journal of Preventive Medicine and Public Health
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• 제41권6호
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• pp.387-396
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• 2008

Objectives : During the past two decades, food deprivation and hunger have been recognized to be not just the concerns of only underdeveloped or developing countries, but as problems for many affluent Western nations as well Many countries have made numerous efforts to define and measure the extent of these problems. Based on these efforts, the theory and practice of food security studies has significantly evolved during the last decades. Thus, this study aims to provide a comprehensive review of the concept and measurement of food security Methods and results : In this review, we introduce the definition and background of food security, we describe the impact of food insecurity on nutrition and health, we provide its measurements and operational instruments and we discuss its applications and implications. Some practical information for the use of the food security index in South Korea is also presented. Conclusions : Food security is an essential element in achieving a good nutritional and health status and it has an influence to reduce poverty The information about the current understanding of food security can help scientists, policy makers and program practitioners conduct research and maintain outreach programs that address the issues of poverty and the promotion of food security.

• Journal of Construction Engineering and Project Management
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• 제5권1호
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• pp.1-10
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• 2015

In construction, stakeholders of extended project team play a key role in the overall project performance. Successful integration of stakeholders demands for good management practices at strategic, operational and project levels. Targets and measures to improve the stakeholder performance encourage the creativity and willingness of stakeholders of extended project team to develop the better ways to achieve the project objectives. This paper presents a generic descriptive method, showing how stakeholder's ability and influence impacts on project performance in the construction sector. The findings of a series of interviews with key informants are presented and the following main conclusion is drawn: improving project performance through stakeholder's contribution and measuring their performance can strengthen the project performance. This innovative approach which redefines the process of improving the project performance in construction projects will be of interest to those who intend to manage the projects in practice as well as to those who interested in advancing theory.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.39-46
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• 2005

에너지 절약형 증류시스템인 열복합 증류탑의 에너지 사용량은 적으나 운전이 어렵기 때문에 실제공정에 활용이 잘되지 않고 있어 에너지 사용은 적으면서 운전성이 개선된 3탑 증류 시스템을 제안하여 상업적인 실제공정인 헥산제조공정에 활용할 때의 에너지 절약성능과 실제 활용에서 생겨나는 문제에 대해 조사하였다. 에너지 회수구조를 활용할 경우, HYSYS를 이용한 시뮬레이션의 결과 기존의 2탑 증류 시스템에 비해 18%의 에너지 절감효과가 있음을 알았으며 2탑 증류시스템에 비해 제어루프의 수는 증가되지만 3가지 제품의 조성 조절이 쉽고 각 탑의 운전압력을 쉽게 조절할 수 있는 장점을 갖고 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1128-1133
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• 2003

A gas driven heat pump (GHP) core design comprises internal combustion engine, compressors incorporated to a cooling/heating system, rubber mountings and belt transmissions. Main excitation farces are generated by an engine, compressors themselves and belt fluctuation. It leads to high vibration level of the mount that can cause damage of GHP elements. Therefore an appropriate design of the mounting system is crucial in terms of reliability and vibration reduction. In this paper oscillation of the engine mount is explored both experimentally and analytically. Experimental analysis of natural frequencies and operational frequency response of the GHP engine mounting system enables to create simplified model for numerical and analytical investigations. It is worked out criteria f3r vibration abatement of the isolated structure. Influence of bracket stiffness between engine and compressors, suspension locations and damper performance is investigated. Ways to reduce excitation forces and improve dynamic performance of the engine-compressor mounting system are considered from these analyses. Implementation of the proposed approach permits to choose appropriate rubber mountings and their location as well as joining elements design A phase matching technique can be employed to control forces from main exciters. It enables to changing vibration response of the structure by control of natural modes contribution. Proposed changes lead to significant vibration reduction and can be easily utilized in engineering practice.

• 교육시설 논문지
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• 제20권5호
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• pp.35-42
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• 2013

It has already been four years as of 2013 since the Departmentalized Classroom System was first introduced following the Korean government's policy. However, no investigation had been made yet on whether the system is properly being managed in practice according to the presented standards, guidelines, and policy direction. Hence, an in-depth investigation and analysis were called for. In line with this, documents were researched, deliberation meetings of experts were held, and the system pilot was tested to develop indices to investigate the state of block-scheduled classes and classes for each student's academic level for the educational classes field. For the school management field, we developed indices to investigate the teachers' organization and their division of labor, administrative officers and work reduction, improvement of teachers' expertise, and the guidance of the students' school life. Based on the indices, we investigated the state of 24 schools, which manage an advanced school system, nationwide. The results showed that the Departmentalized Classroom System has now reached the settling stage, which is beyond the introductory stage, and that it needs to be systematically supplemented for it to be settled in a stable manner.

• 환경영향평가
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• 제20권3호
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• pp.411-424
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• 2011

Over the past three decades, Korea has undertaken a series of reforms to improve development policy, plans and programs, including measures to mainstream the environment across all major sectors. Despite of these efforts, there has been still the lack of capacity to fully assess the environmental impacts as well as sustainable implications of development projects and strategies. At the level of regional and sectoral development plans, the development of strategic environmental assessment SEA systems continues to remain at a relatively early stage in the region with fewer examples of fully operational processes or effective practice. This study shows a further information to our understanding of the EIA and SEA systems and their implementation in Korea. It affords a number of insights into strengths and weaknesses of the current action in different countries, and identifies an agenda of needs and options for capacity building for implementing the EIA enactment.

• 한국농림기상학회지
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• 제10권3호
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• pp.107-112
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• 2008

"Jeung-Bo-San-Lim-Gyeong-Je" (meaning "Revised Forest Management") has been well recognized as the informative document that introduces scientific knowledge and experiences of Korean ancestors regarding weather and climate. The tradition of Gwan-Cheon-Mang-Gi(i.e., empirical forecasting of short-term weather phenomena based on the status of cloud or sky) has been continuously utilized as a civilian weather forecasting method and even for very short-term weather prediction by operational forecasters these days. This agricultural technology textbook, published during the Great King Youngjo in Chosun-Dynasty, may be regarded as a poorly written document from the modern standpoint. Nonetheless, this study demonstrates that by and large the empirical knowledge contained in the book is indeed science based although their applications are limited to several hours for local forecasts in agricultural practices and daily living. For example, the wisdom of keeping water at an optimum level in a paddy field after sowing to prevent young seedlings from late frost damages was not at all different from the present technique of vinyl covered seedling nursery.

• 인터넷정보학회논문지
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• 제17권6호
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• pp.113-122
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• 2016

Information and Communication Technology (ICT) has revolutionized the world and has profound impact on the social and economic development of a country. Implementation, practice and accessibility of ICT is viewed as an integral part of any countries' strategy today. These new technologies are becoming popular due to their ability to produce, distribute and provide instant access to massive information in no time. ICT has pervaded almost every aspect of human endeavor that may include health, education, economics, governance, entertainment etc. Tourism is one such vital industry that find enormous application of ICT in its strategic and operational level, to promise long term benefits and enhance economic growth. Tourism industry in western world and some developed countries of Asia have applied ICT for more than 30 years, and have gained tremendous benefits. Nepal which is also growing as one of the favourite tourist destinations lacks proper implementation of ICT in this industry. In our study we examined how the ICT can play a vital role in developing the tourism industry of Nepal. This study is an exploratory research based on primary data collected from tourist visiting Nepal, supported by information from tour operators, government agencies, NGOs and INGOS. A framework is devised on the basis of data and information collected and finally, discussions elaborate on the prospect and challenges of implementation of ICT in tourism industry of $Nep{\grave{a}}l$.