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        검색결과 1,543

        162.
        2018.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        기후변화로 인한 곰솔림과 소나무림의 세력은 약해질 것으로 예상되고 있으나, 곰솔과 소나무에 대한 식재요구도는 여전히 높은 실정이다. 이에 본 연구는 한반도 난온대림지역에 속하는 부산일대, 남동부지역에 주요 조경수목인 소나무 림과 곰솔림을 대상으로 자연림의 생육밀도를 파악한 후 난온대림에 적합한 생태적 식재밀도를 제시하고자 하였다. 연구는 한반도 남동부에 해당하는 부산광역시를 중심으로 소나무림 22개소, 곰솔림 60개소를 선정하여 100m² 방형구 를 설치하여 조사구 내 출현하는 교목, 아교목층 수종의 흉고직경 및 개체수를 조사한 후, 회귀분석을 통해 평균흉고직 경급별 적정 개체수 산정을 위한 회귀식을 도출하였다. 회귀분석 결과, 흉고직경의 생장에 따른 교목층 생육개체수 예측모형의 결정계수는 곰솔림 0.700, 소나무림 0.533으로 단일 요인에 의한 설명력으로는 매우 높은 것으로 분석되었 다. 예측 회귀모형은 곰솔림의 경우 Y= 31.176e -0.055χ , 소나무림의 경우 Y= 38.351e -0.059χ (X=흉고직경, Y=개체수 /100m²)였다. 남동부지역의 곰솔림과 소나무림의 생육밀도는 중부지방보다 다소 높았다.
        4,000원
        163.
        2018.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        독특한 경관특성과 높은 보존적 가치에도 불구하고, 사구와 관련된 곤충 다양성 연구는 매우 부족한 편이다. 따라서 본 연구에서는 태안해안국립공원에서 주로 관찰되는 사구와 방풍림(해송)에서 서식하는 지표성 딱정벌레류 군집 구조에 대한 비교 연구를 수행하였다. 2014년 6월 중순부터 10월 중순까지 함정트랩을 이용하여 방풍림 5개 지점과 사구 3개 지점을 조사하였다. 조사 결과, 총 2,335개체의 지표성 딱정벌레류를 채집하였으며, 이들은 15속 30종으로 동정되었다. 사구에서는 24종이 채집되었는데, 둥근칠납작먼지벌레(158개체)와 등빨간먼지벌레(153개체)가 우점하였다. 반 면, 방품림에서는 14종이 채집되었고, 둥근칠납작먼지벌레(1,630개체), 윤납작먼지벌레(130개체) 및 붉은칠납작먼지벌 레(42개체)가 우점하였다. 방풍림과 사구의 지표성 딱정벌레류 종 구성의 유사도는 27.4%로 낮았다. 본 연구 결과는 태안해안국립공원에서 발견되는 사구 지형이 방풍림과 비교해서 다른 곤충 군집을 보유하고 있음을 보여주고 있으며, 이는 향후 곤충 보전을 위한 중요한 정보가 될 것이다.
        4,000원
        164.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Korea’s five leading industries-chemical, automobile, shipbuilding, metal and electronics-have been the growth engines of the Korean economy for the last 30 years. However, with their performance weakening in the past few years, Korea’s annual growth rate has dropped to less than 2%. Just as the Japanese economy struggled through the lost decades, Korea’s leading industries have been facing signals of arriving at a Strategic Inflection Point (“SIP”) since the mid-2000s. The objective of this study is to present an appropriate value strategy for Korean firms in leading industries to gain sustainable competitive advantages. This paper examines the following issues : First, it diagnoses the signs and timing of SIP for the five leading industries. Second, this study examines 78 Korean and Japanese firms in order to understand the adaptation strategies of the highest and lowest performing firms from a value strategy point of view. Third, it empirically analyzes the correlation between the indicators of value strategy and the accounting performances of the Korean and Japanese firms. The data set used in the cluster analysis were collected from KISLINE database of NICE Information Service and annual reports. The findings in the case analyses of high and low performing companies show that high value-added specialty chemical materials and electronic component manufacturers that had a strong focus on value creation were defined as high performing companies. And in the cosmetic and automobile industries, companies with a strong emphasis on value appropriation gained high performance. Furthermore, the study conducted a cluster analysis based on two indicators R&D and advertisement expense. The analysis shows that a significant gap exists in the operating incomes among three groups classified under the value strategy. The study recommends that Korean firms are requested to increase R&D expenditure, conduct M&A and collaborate with companies that own source technologies to narrow the technology gap and improve their segment portfolio from commodity to value-added products.
        4,600원
        165.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The distribution of benthic macroinvertebrates was investigated at 1,157 sites of 7 main water systems in Korea, including 442 sites of Han River system (Namhan River, Bukhan River, Han River main stream, Anseongcheon, etc.), 305 sites of Nakdong River system (Nakdong River, Hyeongsan River, Taehwa River, etc.), 199 sites of Geum River system (Geum River, Sapgyocheon, Mangyeong River, Dongjin River, etc.) 102 sites of Seomjin River system (Seomjin River), 102 sites of Yeongsan River system (Yeongsan River, Tamjin River, etc.), and 7 sites of Jeju stream system. A total of 151 families were found in the whole survey sites, including 141 families in Han River, 122 in Nakdong River, 115 in Geum River, 106 in Seomjin River, 113 in Yeongsan River, and 50 in Jeju. Chironomidae (20.8%) was the most dominant species in Korea, followed by Hydropsychidae (17.1%), Baetidae (12.6%), Tubificidae (10.3%), Heptageniidae (8.6%), Ephemerellidae (6.3%), Asellidae (2.7%), Leptophlebiidae (2.4%), Planariidae (1.7%), and Tipulidae (1.6%). Substrates compositions consisted of large sand (22.6%), large gravel (18.4%), silt (10.5%), and boulder (8.2%). The mean stream width was 133.5 m and the mean watercourse width was 61.7 m. The mean water depth and velocity were 30.2 cm and 33.1 cm s-1, respectively. Results of cluster analysis based on distributional characteristics of benthic macroinvertebrates were divided into six groups according to the frequency of benthic macroinvertebrate taxa which appeared in the study area. Finally, altitude, current velocity and substrate composition were the most influencial factors determining the distribution patterns of macroinvertebrate communities.
        4,200원
        166.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        'Dakyeong' (Avena sativa L.), a winter oats for forage use, was developed by the breeding team at National Institute of Crop Science, RDA in 2016. It was derived from a cross between ‘CI7505’(IT133304) and ‘Swan’(IT197920). Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Iksan and Jeonju, respectively. After preliminary and advanced yield test for 2 years, ‘SO2004009-B-B-10-8-3-9’, designated as a line name of ‘Gwiri91’, were subsequently evaluated for earliness and forage yield during 3 years in four parts such as Jeju (upland), Yesan (upland), Iksan (upland), and Jeonju (paddy), from 2014 to 2016, and finally named as ‘Dakyeong’. Cultivar ‘Dakyong’ has leaves of dark green color, thick diameter culm and long grain of brown color. Over 3 years, the heading date of ‘Dakyeong’ was about 5 days earlier than that of check cultivar ‘Samhan’ (April 30 and May 5, respectively), and their average forage dry matter yield harvested at milk-ripe stage was higher 12% (15.7 tone ha-1) than 14.0 tone ha-1 of check cultivar. Cultivar ‘Dakyeong’ was lower than the check cultivar ‘Samhan’ in terms of the protein content (6.1% and 7.0%, respectively) and total digestible nutrients (62.1%, and 62.5%, respectively), while the TDN yield was more than the check (7.79 tone ha-1 and 7.64 tone ha-1, respectively). Fall sowing cropping of ‘Dakyeong’ is recommended only in areas where average daily minimum mean temperatures in January are higher than -6°C, and it should not be cultivated in mountain areas, where frost damage is likely to occur.
        4,000원
        167.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        There has been growing concern over the emissions of formaldehyde and VOCs from automotive interior materials, as these could have an important impact on the in-vehicle air quality (IVAQ) of automotive vehicles. Odor, the components of which may include VOCs, refers to the automotive interior smell emitted directly or indirectly from any part of an automotive interior, based on human olfactory senses and a comfort evaluation of vehicle quality. The objective of this paper is to compare the instrument analysis with the sensory characteristics of an odor using GC/MS/Olfactometry. From the test, it was possible to identify the cause of odor, which can be difficult to distinguish among multiple odors, through the simultaneous performance of instrumental analysis and sensory evaluation.
        4,000원
        168.
        2018.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Oats (Avena sativa L.), which are known as one of the forage crops of Korea, have good livestock palatability and are popular to cattle farmers because of their high dry matter. However, the cultivation of double cropping in the rice field was reluctant due to the late maturing for farmers to plant rice continuously. 'Hi-early', a winter oats for forage use, was developed by the breeding team at National Institute of Crop Science, RDA in 2016. It was derived from a cross between ‘517A2-121’(IT133383) and ‘CI7604’ (IT133379). Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon, Iksan and Jeonju, respectively. After preliminary and advance yield test for 2 years, ‘SO2004015-B-B-23-1-3-7’, designated as a line name of ‘Gwiri92’, were subsequently evaluated for earliness and forage yield during 3 years in four parts such as Jeju (upland), Yesan (upland), Iksan (upland), and Jeonju (paddy), from 2014 to 2016, and finally named as ‘Hi-early’. Cultivar ‘Hi-early’ has the characteristics of medium leaves of green color, thick diameter culm, and medium grain of brown color. Over 3 years, the heading date of ‘Hi-early’ was about 9 days earlier than that of check cultivar ‘Samhan’ (April 26 and May 5, respectively). Average forage fresh yield of ‘Hi-early’ harvested at milk-ripe stage was similar to check cultivar (40.2 tone ha-1 and 40.0 tone ha-1, respectively), and dry matter yield also was similar to check cultivar (14.2 tone ha-1 and 14.0 tone ha-1, respectively). Cultivar ‘Hi-early’ was lower than the check cultivar ‘Samhan’ in terms of the protein content (6.2% and 7.0%, respectively) and total digestible nutrients (61.0%, and 62.5%, respectively), while the TDN yield was more than the check (7.91 tone ha-1 and 7.64 tone ha-1, respectively). Fall sowing cropping of ‘Hi-early’ is recommended only in areas where average daily minimum mean temperatures in January are higher than -6°C, and it should not be cultivated in mountain areas, where frost damage is likely to occur.
        4,000원
        169.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        함정 외부 탑재 장비의 복잡한 형상에 의해서 발생하는 다중반사는 경로를 예측하기 어렵고 높은 RCS(Radar Cross Section) 의 원인이 된다. 따라서 함정의 외부 탑재 장비의 최적배치 설계가 RAS(Radar Absorbing Structure) 방법으로 고려되어야 한다. 본 논문에 서는 함정 외부 탑재 장비에서 발생하는 다중반사와 RCS를 최소화하기 위하여 함정 외부 탑재 장비 최적배치를 수행하였다. 외부 탑 재 장비 최적배치에 사용된 알고리즘은 순차적 내림차순 방법을 이용하였다. 함정 외부 탑재 장비 최적배치를 수행하기 위하여 LCS-2 type을 해석 모델로 선정하였다. 계산 비용을 줄이기 위해서 장비의 기여도 분석 및 다중반사 경로 분석 등을 통해 최적 배치를 수행 할 장비를 선정하였고 최적배치를 통해 RCS가 최소가 되는 최적배치 위치를 도출하였다. 또한 RCS 변화에 따른 레이다의 탐지거리 변 화율을 이용하여 RCS 감소효과를 분석 하였다.
        4,000원
        170.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        해상교통안전진단제도는 선박통항에 영향을 미치는 수역이나 시설의 변경 시 선박통항 안전성 여부를 사전에 평가하고자 도 입되었다. 동 제도의 도입 이후 지난 2014년 대상사업의 범위를 한정하여 길이 100미터 이상 및 최고 속력 60노트 이상인 선박을 대상사 업의 기준으로 설정하였다. 본 연구에서는 이렇게 설정된 대상선박 기준을 해사안전법의 교통안전특정해역, 유조선통항금지해역 등의 대 상선박 기준과 비교 검토하고, 안전진단 대상선박 현황 및 안전진단 제외사례를 분석하였다. 분석 결과, 교통안전특정해역에서 1,000G/T 이상, 유조선통항금지해역에서 794G/T 이상의 위험화물운반선에 대하여 안전진단이 필요한 것으로 나타났고, 여객선 및 위험화물운반선 에 대하여 보다 강화된 기준 적용 필요성이 제기되었다. 따라서 결론으로 대상선박 기준 재검토 필요성을 제시하였다.
        4,000원
        171.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        태안해안국립공원의 곤충상에 관한 연구는 1996년 1차 자연자원조사를 시작으로 2005년부터 2014년까지 조사되었다. 조사된 지점은 대부분 해안지역, 사구, 배후초지 등이었다. 채집방법은 포충망을 이용한 채어잡기(Sweeping), 흡충관 (Suction), 함정트랩(Pitfall trap), 야간조사(Light trap), 말레이즈트랩(Malaise trap)을 사용하였다. 총 17목, 215과 1,540종의 곤충상이 확인되었다. 나비목이 가장 큰 점유율을 가진 분류군으로 나타났고(34.2%), 그 뒤를 이어 딱정벌레목 (28.3%), 노린재목(12.7%), 파리목(8.5%), 벌목(7.1%), 메뚜기목(4.7%), 잠자리목(2.0%), 기타목의 순으로 나타났다. 2007년 12월에 발생한 허베이스피리트호 태안 유류유출 사고 전 후로 사질성 곤충상의 변화를 비교한 결과, 전체 조사기간 동안 대부분 딱정벌레목에 속하는 45종의 사질성 곤충이 조사되었고, 유류오염이 사질성 곤충 출현 종 수에 미치는 영향은 적은 것으로 나타났다.
        4,000원
        172.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out in Suwon-central plain, and Cheorwon, mid-northern plain of Korea to evaluate agricultural characteristics including heading date and yield component for North Korean rice germplasm. The difference between two regions of the heading dates of germplasm was recognized the significance and early matured group growing in Cheorwon tended to flower earlier than that of Suwon while mid-early matured group showed an opposite result. The other agricultural characteristics such as culm length, panicle length, number of panicles per hill, number of grains per panicle, and ripened grain ratio, of the two regions of all traits were highly significant, especially culm length and panicle length in Suwon were longer than those were growing in Cheorwon. Number of panicles per hill and number of grains per panicle in Suwon were more than that were growing in Cheorwon, and ripened grain ratio in Suwon was higher than that of Cheorwon. The another difference between both the regions, of 1000-grain weight was not significant while the effect of interaction between the regions and variety was highly significant. Whereas brown/rough rice ratio and milled rice yield were highly significant; higher in Cheorwon for brown/rough rice ratio and in Suwon of milled rice yield. Additionally, the results concluded that, the North Korean rice germplasm showed susceptible response to bacterial leaf blight(BLB) races such as K2. K3, and K3a but more than mid-range resistant response to rice blast.
        4,000원
        173.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A new barley(Hordeum vulgare L.) cultivar ‘Dachung’ having high forage yielding and good silage quality was developed at National Institute of Crop Science, RDA in 2015. This cultivar was derived from a cross of the ‘Sunwoo’ and ‘Keunalbori1ho’ in 2002. And it’s promising line showed both high yield and lodging resistance through the preliminary and advanced yield trials(PYT, AYT) at Iksan from 2010 to 2012. It was designated as the ‘Iksan479’. ‘Iksan479’ was conducted to regional yield trials(RYT) in six locations around Korea for three years from 2013 to 2015. And it was released as the name of ‘Dachung’. It has erect plant type, growth habit of IV and green leaf. In the paddy field its heading date was April 24 and maturing date was May 26, same day with ‘Youngyang’. Plant height of ‘Dachung’ was 99cm. Dachung’s spikes per m2 was 625. It has high rate of leaf blades, resistance to BaYMV(Barley Yellow Mosiac Virus) and better winter hardiness than that of ‘Youngyang’. The average dry matter of ‘Dachung’ was about 11.9 ton ha-1 in paddy field. And average feed quality of ‘Dachung’ was 9.0% of crude protein content, 31.3% of ADF (Acid Detergent Fiber), 54.4% of NDF (Neutral Detergent Fiber), 64.0% of TDN (Total Digestible Nutrients). ‘Dachung’ had grade I of silage quality. This cultivar would be suitable for the area above the daily minimum temperature of -8℃ in January in Korean peninsula.
        4,000원
        174.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This study analyzed the difference in a driver’s workload between using a driving simulator and field driving in tunnel, highway.METHODS: Based on the literature review, it was found that a driver’s workload could be quantified using biosignals. This study analyzed the biosignal data of 30 participants using data collected while they were using a driving simulator and during a field test involving tunnel driving. Relative energy parameter was used for biosignal analysis.RESULTS : The driver’s workload was different between the driving simulator and field driving in tunnels, highway. Compared with the driving simulator test, the driver’s workload exhibited high value in field driving. This result was significant at the 0.05 level. The same result was observed before the tunnel entrance section and 200 m after the entrance section.CONCLUSIONS: This study demonstrates the driving simulator effect that drivers feel safer and more comfortable using a driving simulator than during a field test. Future studies should be designed considering the result of this study, age, type of simulator, study site and so on.
        4,000원
        175.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Leap Motion is a virtual reality controller which allows users to interact with the virtual objects using their bare hands. However, the controller only allows the detection of hands up to 60cm from the sensor, which means that users cannot interact with virtual objects outside the same range in the virtual space. In this paper, we propose a new interaction method to overcome the limitation of the manipulation range. The movement of virtual hands in the virtual space is accelerated by the velocity of the hand movement and the range of the reachable virtual space is expended to the current view of the virtual space. Experimental results show that users can manipulate long-distance objects in a coherent and convenient way.
        4,000원
        176.
        2017.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In the present study the microstructure of low-carbon steels fabricated by controlled rolling and accelerated cooling processes was characterized and identified based on various microstructure analysis methods including optical and scanning electron microscopy, and electron backscatter diffraction(EBSD). Although low-carbon steels are usually composed of α-ferrite and cementite(Fe3C) phases, they can have complex microstructures consisting of ferrites with different size, morphology, and dislocation density, and secondary phases dependent on rolling and accelerated cooling conditions. The microstructure of lowcarbon steels investigated in this study was basically classified into polygonal ferrite, acicular ferrite, granular bainite, and bainitic ferrite based on the inverse pole figure, image quality, grain boundary, kernel average misorientation(KAM), and grain orientation spread(GOS) maps, obtained from EBSD analysis. From these results, it can be said that the EBSD analysis provides a valuable tool to identify and quantify the complex microstructure of low-carbon steels fabricated by controlled rolling and accelerated cooling processes.
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