• Journal of Biosystems Engineering
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• 제40권1호
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• pp.19-27
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• 2015

Purpose: A system to measure the visibility of agricultural tractor operators was designed and evaluated according to ISO standards, and a blind area diagram around the tested tractor was created based on the manual method recommended by the National Institute for Occupational Safety and Health (NIOSH). Methods: A visibility measurement system was designed and evaluated based on the ISO 5006 and ISO 5721-1 standards. Two bulbs used to simulate the operator's eyes were mounted on a bar with a supporting frame. A wooden frame was used to determine the seat index point position. The 12-m visibility test circle was divided into six sectors of vision, and the test tractor was placed at the center of the circle. Artificial light was supplied in the darkened environment, and shadow or masking effects were measured manually around the 12-m circle. Results: When the bulbs were placed at the operator's eye level, front visibility was good; no masking was found in the "A" vision sector, but larger masking widths were found in the "B" and "C" vision sectors. Since the masking width exceeded 700 mm, additional tests, such as movement of the light sources to both sides of the operator's eye level, were performed. Less than six masking effects were found in the semi-circle of vision to the front, and more than one masking was found in the "B" and "C" visual fields. The minimum distance between the centers of two masking effects exceeded 2500 mm when measured as a chord on the semi-circle of vision. A blind area diagram was created to define the exact nature of the blind spots and mirror visibility. Conclusions: Visibility evaluation is an effective way to enable proper and safe operation for agricultural tractor operators. Inclusion of this visibility evaluation test in the general testing process might aid tractor manufacturers.

• 한국위성정보통신학회논문지
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• 제3권2호
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• pp.1-6
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• 2008

시공간 부호(Space-time codes; STC)는 부가적인 대역폭 요구 사항 없이도 다중경로 환경에서 부호화 이득을 얻을 수 있는 효율적인 방식이다. 위성시스템에서도 시공간부호를 이용하여 지상 중계 장치와의 협동 다이버시티 이득 구현이 가능함이 제안되어 왔다. 특히 위성 DMB 시스템에서는 방송 서비스의 단방향 특성으로 인하여 전송 다이버시티를 이용하여 성능을 향상시키는 것이 매우 효율적이라고 할 수 있다. 본 논문에서는 차세대 위성 DMB 서비스의 성능을 향상시키는데 기여할 수 있는 여러 가지 STC 방식의 성능을 비교한 결과를 제시한다. 본 논문에서 제시하는 방식들은 위성과 지상의 중계기가 서로 협동적으로 동작하여 STC 부호화 이득을 얻을 수 있도록 하는 방식이다. 또한, 향후 이런 방식들을 개발함에 있어서 고려해야 할 점들을 기술한다.

• 농촌계획
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• 제6권2호
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• pp.82-93
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• 2000

The concept of sustainable development in rural area, which is focused on both preservation of nature and human's amenity, has been common paradigm. The purpose of this study is to suggest the development directions for the environmentally friendly rural house. The planning items for developing sustainable rural house were selected through literature survey, case study, and their adaptation evaluation. The establishment of principles and the evaluation of planning items were analyzed by a survey to experts. The results are as follows : 1) It is showed that sustainability evaluation of rural village is rated as above the moderate degree, but rural house is rated as 3.4(average score). Especially, there were lowly evaluated the utility, material, structure and inner environment in rural house. 2) It is revealed that 76.7% of planning items are located in both the upper left and upper right hand quadrant of the action grid, which is drawn by the importance-performance analysis(IPA). And any item is not found in the lower right hand quadrant(Possible Overkill). 3) Two basic principles and eight optional principles we identified by analysis of factor and regression. The rural zone is identified as major effective element for applying planning items into the rural house development. So it is desirable to apply the items differently by the rural zone type. 4) In view of sustainable development, it is desirable for rural village to have about 50 houses, and for rural house to have $155{\sim}180$ pyung(坪) as lot size, 30% as ratio of building, and 60% as building volume.

• 환경생물
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• 제30권2호
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• pp.77-89
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• 2012

With the advent of the genomics era powered by DNA sequencing technologies, life science is being transformed significantly and biological research and development have been accelerated. Environmental biology concerns the relationships among living organisms and their natural environment, which constitute the global biogeochemical cycle. As sustainability of the ecosystems depends on biodiversity, examining the structure and dynamics of the biotic constituents and fully grasping their genetic and metabolic capabilities are pivotal. The high-speed high-throughput next-generation sequencing can be applied to barcoding organisms either thriving or endangered and to decoding the whole genome information. Furthermore, diversity and the full gene complement of a microbial community can be elucidated and monitored through metagenomic approaches. With regard to human welfare, microbiomes of various human habitats such as gut, skin, mouth, stomach, and vagina, have been and are being scrutinized. To keep pace with the rapid increase of the sequencing capacity, various bioinformatic algorithms and software tools that even utilize supercomputers and cloud computing are being developed for processing and storage of massive data sets. Environmental genomics will be the major force in understanding the structure and function of ecosystems in nature as well as preserving, remediating, and bioprospecting them.

• 펄프종이기술
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• 제47권5호
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• pp.80-84
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• 2015

Softness is considered one of the most important attributes of hygiene paper such as tissue and towel. Being subjective in nature, however, softness attribute has been generally believed to be impossible to evaluate using objective methods. Hallmark in his pioneering work proposed that tissue subjective softness should be mainly consisted of the bulk softness component and surface softness component. The bulk softness component can be determined by tensile stiffness; the surface softness component by surface tester. The surface friction turns out far more important than the surface roughness in determining the surface softness component. It cannot be too much emphasized that both results of the tensile stiffness and the surface friction should depend on measuring conditions such as an instrument used, sample sizes (e.g., basis weight, length, and width) and operating conditions of the instrument (e.g., gauge length, cross-head speed, size of stylus, and its scanning speed). This indicates that a direct comparison of the test results would be impossible or misleading unless they have been tested under the identical conditions. This may explain why the standard objective test method for tissue softness has not been available at present.

• 공업화학
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• 제21권5호
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• pp.570-574
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• 2010

기존 단열재의 주된 기능은 단지 열전달을 차단하는 기능과 건물로부터 열손실을 줄여주는 기능만을 수행했다. 반면, 축열재는 특정온도 범위 내에서 열에너지를 저장 또는 방출함으로써 건물에너지 사용량을 절감할 수 있다. 축열 건자재는 실내 공기온도 변화주기를 효과적으로 조절하여 일정하게 온도를 유지시킬 수 있다. 결과적으로 냉난방시스템 기능을 효율적으로 향상시킬 수 있다. 본 연구는 건축자재로 많이 이용되고 있는 석고보드에 상변화잠열물질을 축열재로 첨가하여 그 물성과 열환경 특성을 파악하였다. 또한 축열 건자재를 활용할 때 발생가능한 문제점을 확인하였다. 마지막으로 TVOC와 HCHO 함량 분석으로부터 오염물질의 배출가능성을 조사하여 축열 건자재의 환경 친화도를 검토하였다.

• 생태와환경
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• 제51권3호
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• pp.212-220
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• 2018

Ecological and ecosystem database is becoming very necessary to understand origins and relationship between human and nature and also to minimize disturbance caused by human activities. An ecological information portal can play important roles as a computing system to collect knowledge, distributed research findings and separated data from researchers. In this study, we designed and developed ecological information portal service (EcoBank 1.0) for collecting and providing ecological information for diverse classes of stakeholders. To reach the goal, we had reviewed related and comparable ecological database portals to design conceptual structure of EcoBank system including database management framework. Then, we developed some functions of ecosystem analysis for each stake-holders (researchers, general public and policy makers). As a result of this study, we successfully designed of EcoBank system covering the functions of Digital Object Identifier(DOI) publishing and data quality management process. Also, we (1) applied ecological indices for calculating biodiversity by administrative boundary for policy makers, (2) provided statistical information of econature map for general public and distribution characteristics of species for researchers. To make a successful establishment of EcoBank, we have to collect and build up related database and offer various and reliable ecological data consistently. We expect that the successful construction of EcoBank will help not only to accomplish sustainable development goals but also to raise the welfare of ecosystem in Korea.

• 기술혁신연구
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• 제20권2호
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• pp.1-28
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• 2012

그동안 출연연은 과학기술 발전을 선도하는 핵심 역할을 담당해 왔으나 최근에는 조직의 경쟁력 문제를 포함하여 그 미션과 역할까지 새롭게 정립해야 하는 시점에 있다. 본 연구는 ETRI를 결정적인 사례로 하여 현재 출연연이 직면하고 있는 구조적 한계와 어려움을 살펴보았다. 분석 결과 출연연의 자체 변화 노력도 문제이지만 출연연이 예산, 인력, 평가 등 통제가 어려운 구조적인 문제에 봉착되어 있음을 알 수 있다. ETRI의 경우 연구개발이나 특정기술 수준에서는 추격에서 탈추격으로 넘어서고 있으나 우리나라 출연(연) 연구 환경과 실제 일하는 방식은 추격형 체제에 머물러 있는 상황이다. 추격의 대상과 수단이 어느 정도 확실했던 추격기를 넘어 어디로 가야하며 무엇을 해야 할 것인가가 불확실한 탈추격 혁신 상황에서는 출연연의 미션 및 역할, 예산 인력 평가 체계, 사업기획 체계 및 프로세스 방식 등이 새롭게 변화될 필요가 있다.

• 한국습지학회지
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• 제12권3호
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• pp.145-153
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• 2010

안양천은 한강 지류의 국가하천으로서, 안양천 수변관리를 위한 생물상 현황조사를 수행하였다. 수변 및 주변지역 조사를 통하여 출현종 및 개체수를 파악하고 생태현황을 나타내는 민감종 및 서식지의 훼손을 방지하기 위한 외래종을 파악하였다. 안양천 수변부에서 출현한 식물상은 35목 78과 196속 230종 33변종 2품종 1잡종의 총 266종류(분류군)가 분포하는 것으로 조사되었으며, 외래종으로는 총 10목 16과 37속 47종 2변종 49분류군이 분포하는 것으로 확인되었다. 하류의 한강 합류부와 상류의 기아대교 하류부의 제방사면에서 외래종이면서 위해식물인 가시박(Sicyos angulatus)이 확인되어 이에 대한 관리대책 수립이 필요할 것으로 판단된다. 안양천 주변을 11개 권역으로 분류하여 생태계교란야생동식물 및 외래종 관리방안과 사람과 자연이 공생할 수 있는 환경창출 방안과 하천 생태축(블루네크워크) 조성방안을 제시하였다.

• 환경생물
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• 제38권3호
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• pp.392-403
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• 2020

This study analyzed the distribution characteristics of invasive alien plants on the islands of the Korean Peninsula. Ten species, Rumex acetosella, Sicyos angulatus, Solanum carolinense, Ambrosia artemisiaefolia var. elatior, Ambrosia trifida, Aster pilosus, Eupatorium rugosum, Hypochaeris radicata, Lactuca scariola, and Paspalum distichum were present on 68 islands. These ecosystem-disturbing invasive alien plants appeared extensively on the islands of Gyeonggi province and Jeollanam province. The proportion of the plants on the inhabited islands (41 places, 2.15 species on average) was higher than that on the uninhabited islands (27 places, 1.07 species on average). This means that the distribution of invasive alien plants was closely related to human activity. The distribution of Ambrosia artemisiaefolia var. elatior(32 islands) and Rumex acetosella (31 islands) was the widest, and there were distinct distribution differences according to species. In the island area, the physical environment is poor compared to the mainland, and the native space is limited. Therefore, when invasive alien species enter and settle on the island, the native island plants can be damaged more than those on the mainland. In this regard, the discussion of the distribution of invasive alien plants in the island region can contribute to the conservation of biodiversity in the region.