• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.638-641
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• 2004

Returned laser pulse has certain relationship with vegetation canopy structure (canopy closure, height, LAI, biomass). This study attempts to analyze the characteristics of airborne laser scanner data over very dense forest canopy. Discrete pulse laser scanner data were obtained on April 25, 2004 along with digital aerial color imagery. Using forest stand maps, 14 sample stands of 7 species groups were selected and the elevations from the first and last laser return were compared. From the preliminary analysis, we found that the difference between the first and last return was higher with deciduous forest stand than in coniferous stand. Although difference between the first and the last laser returns often corresponds to tree height, it would not be the case for the forest site having very dense canopy structure.

• Applied Biological Chemistry
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• 제15권1호
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• pp.41-47
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• 1972

새로 육종된 다수성 품종인 IR 667-수원 213과 진흥을 사용하여 출수후 군락구조의 등적 변화를 질소영양과 관련하여 비교분석한 결과 다음과 같았다. 1. 군락주조 패턴 (출수기 건물중 수직분포)은 진흥에서는 수직형이고 IR 667에서는 수평형이었다. 2. 엽면적 밀도 (또는 무게)의 수직분포 패턴이 IR 667은 중앙부 우세형으로 진흥은 상부 우세형으로 분류되었다. 3. 군락구조 보존패턴과 엽면적 백분율 분포패턴은 엽면적밀도의수직분포패턴을 따랐다. 4. 군락보존력은 IR 667이 약하여 군락보존율이 낮으며 이는 엽의노화가 빠른것을 나타낸다. 5. 질소영양이 군락구조패턴에 거의 영향을 주지 않지만 질소의 느린공급(유황입힌요소)은 구조의 중앙부를 보존하여 상부우세형을 중앙부 우세형으로 변환 시키려는 경향을 보였으며 그것이 수량 증가의 원인이 된것같다. 6. 증앙부우세형과 상부우세형은 곡실생산에서의 상위엽의존형과 하위엽 의존형에 각기 잘 적합한것 같다.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.74-83
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• 2009

This study is subway station canopy evaluation to improve the landscape of a street furniture design. From a survey of the professional abstracted the design elements of subway station canopy in Daegu. And then, it practiced a canopy design appreciation by the analysis of appreciation items. The results are as follows. First, this research analyzes each quality a classified by the four characteristics at the subway station. In general station case, the slope roof was consistent in used to be unified. If the symbol of the express station wasn't common in cross-section or material. In addition, the design evaluation in the lower canopy were evaluated. Therefore, in case of the city installed in the canopy, the characteristic of city gateway and the symbolic characteristic of a design that is required. Second, subway station canopy existed in widely opened site come out a lower rating about safety. Therefore, considering the safety light device or system need to do. Third, if the horizontal or sloping roof shape come out in a lower rating, the highly evaluated curve shape is considered to apply. Forth, a structure material of the canopy was highly evaluated the aluminum composite panels and structural steel pipes. Therefore, to improve a beauty of the city, to give rhythm to a structure material of the canopy of the aluminum composite panels and structural steel pipes will be desirable to use as the main ingredient.

• 한국군사과학기술학회지
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• 제18권4호
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• pp.369-375
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• 2015

In this paper, transparent circuit analog radar absorbing structure with angular stability for stealth aircraft canopy was proposed and designed. To obtain wideband electromagnetic absorption, optical transparency and smaller thickness, we proposed the novel FSS(Frequency Selective Surface) for X-band and implemented the resistive FSS and PEC(Perfect Electric Conductor) plane using ITO(Indium Thin Oxide) coating with optical transmissivity of 90 %. Reflection loss characteristics for different incident angles of both TE(Transverse Electric) and TM(Transverse Magnetic) polarizations are presented through simulations. We then fabricated the proposed structure to verify the simulation results. The comparisons between the simulation and measured results show good agreements. The results also show that the proposed radar absorbing structure can provide better frequency stability for different incidence angles and polarizations as well as optical transparency. We can apply this proposed structure to the canopy of stealth aircraft and other stealth applications for visible transparency.

• 기술사
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• 제34권5호
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• pp.29-33
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• 2001

This paper summarizes the design and construction of the roof canopy structure for the SEOUL 2002 World Cup Main Stadium with a design inspired by Korean traditional beauty emphasizing images of the Pangpae kite. The stadium has also been designed for maximization of its post-World Cup utility to be used on as every basis by the citizens. The stadium canopy is a unique spatial network of truss members with a tensile membrane roof suspended from 16 masts. The canopy covers 40,950 ㎡. which is clad with a pre-stressed tensile membrane of PTFE coated fiberglass fabric and the glass.

• Current Optics and Photonics
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• 제1권2호
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• pp.113-117
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• 2017

With the increasing use of high-power laser diode bars (LDBs) and stacked LDBs, the issue of thermal control has become critical, as temperature is related to device efficiency and lifetime, as well as to beam quality. To improve the thermal resistance of an LDB set, we propose and analyze a bypass heat sink with a top canopy structure for an LDB set, instead of adopting a thick submount. The thermal bypassing in the top-canopy structure is efficient, as it avoids the cross-sectional thermal saturation that may exist in a thick submount. The efficient thickness range of the submount in a typical LDB set is guided by the thermal resistance as a function of thickness, and the simulated bypassing efficiency of a canopy is higher than a simple analytical prediction, especially for thinner canopies.

• Journal of Ecology and Environment
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• 제41권1호
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• pp.1-8
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• 2017

Background: Though the biomass of floral vegetation in understory plant communities in a forested ecosystem only accounts for less than 1% of the total biomass of a forest, they contain most of the floral resources of a forest. The diversity of understory honey plants determines visitation rate of pollinators such as honey bee (Apis mellifera) as they provide rich food resources. Since the flower visitation and foraging activity of pollinators lead to the provision of pollination service, it also means the enhancement of plant-pollinator relationship. Therefore, an appropriate management scheme for understory vegetation is essential in order to conserve pollinator population that is decreasing due to habitat destruction and disease infection. This research examined the diversity of understory honey plant and studied how it is related to environmental variables such as (1) canopy density, (2) horizontal heterogeneity of canopy surface height, (3) slope gradient, and (4) distance from roads. Vegetation survey data of 39 plots of mixed forests in Chuncheon, Korea, were used, and possible management practices for understory vegetation were suggested. Results: This study found that 113 species among 141 species of honey plant of the forests were classified as understory vegetation. Also, the understory honey plant diversity is significantly positively correlated with distance from the nearest road and horizontal heterogeneity of canopy surface height and negatively correlated with canopy density. Conclusions: The diversity of understory honey plant vegetation is correlated to vegetation structure and human impact. In order to enhance the diversity of understory honey plant, management of density and height of canopy is necessary. This study suggests that improved diversity of canopy cover through thinning of overstory vegetation can increase the diversity of understory honey plant species.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.72-74
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• 2003

Forest canopy density is an ideal representative of the forest habitat situations. It can directly or indirectly depict the canopy structure and gap size in the forestland, thus could be applied to assessment of wildlife’s diversit y. Since population survey of vegetation and wildlife diversities is a key issue for sustainable forest ecosystem management, many research efforts have been focused on forest canopy density using multispectral data in the last two decades. Unfortunately, prediction of canopy density using large scaling remote sensing data remains a challenging issue. Due to recent advances in hyperspectral image sensors hyperspectral imagery is now available for environmental monitoring. In this paper, we conduct experiments to monitor complicated environments of forestland that can be captured by using hyperspectral imagery and further be analyzed to test a prediction model of forest canopy density. The results show that 95% of canopy density could be well described by using 2 difference vegetation indices (DVIs), which are difference of blue and green reflectances rband_100-rband_150 and difference of 2 short wave infrared reflectancse rband_406-rband_410 With the wavelengths of band no. 100, 150, 406, and 410 specified by 462.39 nm, 534.40 nm, 918.22 nm and 924.41 nm respectively.

• 한국토양비료학회지
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• 제5권1호
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• pp.9-15
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• 1972

새로 육종(育種)된 다수성(多收性) 품종인 IR677계통(수원 213 및 214)과 진흥(振興) 및 팔달(八達)을 사용 포장상태(圃場狀態)에서의 군란구조(群落構造)를 비교분석(比較分析)하여 다음과 같은 결과(結果)를 얻었다. 1) IR667계통 (IR8${\times}$Taichung Native 1${\times}$Yukara)은 군락(群落)높이가 낮고 개벽도(開蘖度)가 크며 개엽도(開葉度)가 적고 엽장비율(葉長比率)(지엽장(止葉長)/3엽장(葉長))이 적고 4+5절간장(節稈長)이 짧으며 5절간(節幹) 직경(直俓)이 커서 결과적으로 엽면적지수(葉面積指數)가 크며 수중형(穗重型)이고 엽중비율(葉重比率)(엽중(葉重)/엽초십간중)이 큰 장점을 갖는 반면 엽폭(葉幅)이 크고 엽수(葉數)(잎수/$m^2$)가 적고 비엽면적(比葉面積)( $cm^2/g$)이 적고 노화(老化)에 의한 군락파양율(군낙파양율)이 큰 단점(短點)을 갖고있다. 2) IR667 계통은 군락구조(群落構造)의 10개(個) 구성요소(構成要素)에 의한 구조(構造)의 평가방식(評價方法)으로 제안(提案) 한 "군락평점(群落評點)"이 훨씬 높으며 결과적으로 수량(收量)도 높았다. 3) 개별엽(個別葉)의 질(質)은 장려품종이 좋은때문에 보다 높은 수량을 위한 조합(組合)은 장려품종의 엽(葉)으로 IR667의 구조(構造)를 갖는 것이다.

• 환경영향평가
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• 제17권5호
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• pp.279-288
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• 2008

Vertical forest distribution is one of the important factors to understand various ecological mechanism such as succession, disturbance and environmental effects. LiDAR data provide information, both the horizontal and vertical distribution of forest structure. The laser scanner survey provided a point cloud, in which the x, y, and z coordinates of the points are known. The objectives of this study were 1) to analyze factors of forest structure such as individual tree isolation, tree height, canopy closure and tree density using LiDAR data and 2) to compare the forest structure between outer and interior forest. The paper conducted to extract the individual tree using watershed algorithm and to interpolate using the first return of LiDAR data for yielding digital surface model (DSM). The results of the study show characters of edge such as more isolated individual trees, higher density, lower canopy closure, and lower tree height than those of interior forest. LiDAR data is to be useful for analyzing of forest structure. Further study should be undertaken with species for more accurate results.