• 한국산림과학회지
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• 제84권4호
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• pp.409-414
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• 1995

발생된 소음(騷音)이 사철나무 수벽(樹壁)의 높이, 두께 및 밀도(密度), 발음점(發音點)의 거리(距離)와 높이, 그리고 수음점(受音點)의 거리(距離)와 높이 등에 따라 얼마나 어떻게 감쇄(減殺)되는 지를 비교 분석한 결과를 요약하면 다음과 같다. 1. 수벽설치전(樹壁設置前)에 대한 설치후(設置後)의 소음 감쇄량(減殺量)은 6.8dB, 감쇄율(減殺率)은 10.6%로 각각 산출되었으며, 이때 t-value는 1% 수준에서 유의성이 인정되었다. 2. 소음의 감쇄효과(減殺效果)와 상관이 가장 높은 요인은 수벽의 밀도(r=-0.768)였으며, 다음으로 수음점의 거리, 수벽의 두께, 발음점의 높이 순으로 부의 상관이 높게 나타났다. 3. 소음 감쇄효과에 기여하는 요인을 편상관계수에 의하여 알아보면, 수벽의 밀도(r=-0.959)가 가장 높았고, 다음으로 수음점의 거리(r=-0.906), 수벽의 두께(r=-0.753) 순으로 높게 나타났다. 4. 수벽의 형상(形狀), 그리고 발음점 및 수음점의 위치(位置)에 따라 소음 감쇄효과를 예측할 수 있는 추정식은 $Y=69.520-1.672X_1-1.656X_2-0.066X_3-0.248X_4-3.134X_5-0.222X_6-0.343X_7$로 도출되었으며, 이때 추정식의 결정계수 $r^2$는 0.950으로 높게 나타났다. 5. 소음 감쇄효과를 나타내는 준부분 상관계수는 수벽의 밀도, 수음점의 거리, 수벽의 두께, 수벽의 높이 순으로 크게 나타났다. 따라서 사철나무 수벽에 의하여 소음 감쇄효과를 높이고자 할 때에는 수벽의 밀도, 수음점의 거리, 수벽의 두께 및 발음점의 거리 등을 적의 조절(調節)하여야 할 것으로 사료된다.

• 한국가구학회지
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• 제17권4호
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• pp.109-114
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• 2006

An investigation was carried out for the annual ring width, longitudinal tracheid diameter and wall thickness in different tree heights for Pinus koraiensis Sieb. et. Zucc. The annual ring width increased along with the tree height, however the tracheid diameter and wall thickness decreased with the tree height. Tracheid wall thickness was found the thickest at 2.0m from the above ground samples and it increased gradually from pith to bark. Radial tracheid diameter was found to be larger than that of tangential tracheid diameter in earlywood. But, it was found to be the opposite in latewood. In earlywood, the average values of tracheid wall thickness was found the range of $2.1-3.0{\mu}m$, whereas, in latewood, it was $2.4-4.2{\mu}m$.

• KIEAE Journal
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• 제12권2호
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• pp.93-101
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• 2012

In this study, we measured the Index of Greeness(I.O.G) and analyzed factors that affect in downtown street of Seoul. The aim of this article is to provide an ways of improving I.O.G, with an emphasis on accuracy of measurement. We utilized the autimatic measurment techniques proposed by Tonosaki to solve the problem of accuracy in measurement. The result is as follows : Firstly, the average I.O.G of Gwanghwamun Plaza is 15.76%, Jongno is 11.48% and Dasanro(from Yaksu station to Beotigogae station) is 6.36%. According to the comprehensive analysis in three reseach areas, it shows that I.O.G is intimately linked with planting method, species of trees and the presence of wall planting. Secondly, it was analyzed that grass and ground-cover planting promote I.O.G better than other method. The I.O.G of photo which contains grass is 45.47%. According to the comparative analysis between tree planting and multi-planting method, the presence of lower planting showed a difference about 8.77% of I.O.G.. From the persipective of I.O.G, tree planting with two lines is more effective than one. The difference of two ways is about 3.24%. Thirdly, it is an efficint way to use the wall planting or vertical planting in order to promote I.O.G.. In Dasanro, The I.O.G of photo which contains wall planting or vertical planting is 45.47% in contrast to the average of I.O.G. is 6.36%. Fourthly, the difference of I.O.G between broadleaf tree and needleleaf tree was larger than we thought. If look closely confined to this study, the I.O.G of street planted by Pine is 3.61% and Eastern Sycamore Family Bottonwood is 12.55%.

• 한국조경학회지
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• 제17권2호
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• pp.1-14
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• 1989

The purpose of this study was to develop the principle of space composition in Jungja of a category of korean traditional space. The results which analyzed outside space, prospect angle and preference factors for landscape with making, Jungja which has artificially constructed pond within Gyeongbug province, the subject of study were as fellows ; Size of pond was quite different in each Jungja, and its form was retangular. There was built circle island or figured ten-long life within pond. These pursued harmony of the cosmic dual force or eternal youth. Average angle of depression and horizontal angle from floor of Jungja to pond were respectively 16$^{\circ}$ 23', 48$^{\circ}$ 26'. Average angle of depression to island in pond was 13$^{\circ}$28'. Average angle of depression from floor of Jungia to wall was 2$^{\circ}$58'. With controlling height of wall, there was maintained privacy and used borrowed landscape. Tree within garden was mainly planted a deciduous tall tree, the important species of tree were bamboo, pomegranate tree, crape myrtle, etc. Variables that gave influence on landscape preference degree were things about tree and pond. On prospecting pond, these variables-feeling for shore protection, impression for water, visual depth to pond feeling for shore protection, impression for water, visual depth to pond-gave Largely influences.

• 대기
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• 제25권4호
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• pp.685-692
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• 2015

In this study, the effects of trees on flow and scalar dispersion in an urban street canyon were investigated using a computational fluid dynamics (CFD) model. For this, we implemented the drag terms of trees to the CFD model, and compared the CFD-simulated results to the wind-tunnel results. For comparison, we considered the same building configuration as the wind-tunnel experiment. The trees were located at the center of street canyon with the aspect ratio (defined as the ratio of the street width to the building height) of 1. First, the flow characteristics were analyzed in the tree-free and high-density tree cases and the results showed that the CFD model reproduced well the flow pattern of the wind-tunnel experiment and reflected the drag effect of trees in the street canyon. Then, the dispersion characteristics of scalar pollutants were investigated for the tree-free, low-density tree and medium-density tree cases. In the tree-free case, the nondimensionalized concentration distribution simulated by the CFD model was quite similar to that in the wind-tunnel experiment in magnitude and pattern. The correlation coefficients between the measured and simulated concentrations are more than 0.9 in all the cases. As the tree density increased, nondimensionalized concentration increased (decreased) near the wall of the upwind (downwind) building, which resulted from the decrease in wind speed case by the drag effect of trees. However, the CFD model underestimated (overestimated) the concentration near the wall of upwind (downwind) building.

• 인터넷정보학회논문지
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• 제18권1호
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• pp.43-50
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• 2017

본 논문에서는 한 장의 실내이미지에서 내벽구조 검출을 위한 개선된 소실점 검출방법과 세그먼트 레이블링 방법을 제안한다. AR 기술 수요의 증가로 이미지로부터 건축물의 구조를 인식하는 것과 관련된 연구가 많이 이루어 지고 있다. 그러나 폐색을 발생시키는 객체들이 많은 실내 이미지에서 실내 내부 구조를 인식하는 것은 여전히 어려운 문제이다. 소실점 검출 방법을 개선하기 위하여 육면체를 이루는 실내 내벽들 사이의 직교성을 이용하는 방법을 제안하였다. 또한 실내 이미지 내의 세그먼트들을 레이블링 하기 위하여 슈퍼픽셀 기반의 군집화 방법과 트리기반 학습기를 통한 레이블링 방법을 제안하였다. 마지막으로 실험 결과에서 제안한 방법들에 의하여 실내 구조 검출 결과가 개선됨을 보였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.279-280
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• 2007

Airway wall thickness is an important bio-marker for evaluation of pulmonary diseases such as stenosis, bronchiectasis. Nevertheless, an image-based analysis of the airway tree can provide precise and valuable airway size information, quantitative measurement of airway wall thickness in CT images involves various sources of error and uncertainty. So we have developed an accurate airway wall measurement technique for small airways with three-dimensional (3-D) approach. To illustrate performance of these techniques, we used airway phantom that consisted of 4 acryl tubes with various inner and outer diameters. Results show that evaluation of interpolation and deconvolution methods of airways in 3-D CT images, and significant improvement over the full-width-half-maximum method for measurement of not only location of the luminal and outer edge of the airway wall but airway wall thickness.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.383-386
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• 2006

In this study, we propose a new fast algorithm for calculating short range forces in molecular dynamics, This algorithm uses a new hierarchical tree data structure which has a high adaptiveness to the particle distribution. It can divide a parent cell into k daughter cells and the tree structure is independent of the coordinate system and particle distribution. We investigated the characteristics and the performance of the tree structure according to k. For parallel computation, we used orthogonal recursive bisection method for domain decomposition to distribute particles to each processor, and the numerical experiments were performed on a 32-node Linux cluster. We compared the performance of the oct-tree and developed new algorithm according to the particle distributions, problem sizes and the number of processors. The comparison was performed sing tree-independent method and the results are independent of computing platform, parallelization, or programming language. It was found that the new algorithm can reduce computing cost for a large problem which has a short search range compared to the computational domain. But there are only small differences in wall-clock time because the proposed algorithm requires much time to construct tree structure than the oct-tree and he performance gain is small compared to the time for single time step calculation.

• 한국산학기술학회논문지
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• 제21권10호
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• pp.77-83
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• 2020

국토를 효율적으로 관리하고 도시문제를 과학적으로 해결하기 위해 최근 스마트시티, 디지털트윈 등 3차원 공간정보 관련 기술이 급격하게 발전하고 있다. 이러한 3차원 공간정보 구축은 주로 영상정보를 이용하여 객체를 3차원 입체화하고 실감형 영상인 텍스처링 영상을 추출하여 객체벽면에 영상을 부여하는 방식으로 수행된다. 하지만 객체 주변의 다양한 요인으로 인해 텍스처링 영상에서는 필연적으로 폐색영역이 발생한다. 이에 본 연구에서는 최근 기술인 딥러닝 기술 중에서 ResNet 알고리즘을 이용하여 건물 폐색을 유발하는 가로수에 대한 데이터셋을 만들고 이에 대한 해결방안을 제시하고자 한다. 연구결과 ResNet 알고리즘의 공간정보 적용 가능성을 판단하고 이를 적용한 레이블링 생성 SW 개발하여 실제 가로수를 대상으로 데이터셋을 구축하였다. 구축된 데이터셋을 텍스처링 영상에 적용하여 정확도와 재현율로 검출능력을 분석하였다. 분석결과를 위해 딥러닝 분야에서 많이 사용되고 있는 정밀도와 재현율을 이용한 F값을 적용하였으며 가로수 단일 객체가 포함된 건물의 측면부 영상과 경사 영상에 대해서는 높은 F값을 도출하여 우수한 성과를 확인하였으나, 같은 해상도를 가진 건물 전면부 영상에서는 그림자 등의 요인으로 F값이 낮음을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제28권10호
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• pp.1760-1768
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• 2018

The type strain Bacillus subtilis subsp. subtilis KCTC $3135^T$ was deeply sequenced and annotated, replacing a previous draft genome in this study. The tar and tag genes were involved in synthesizing wall teichoic acids (WTAs), and these genes and their products were previously regarded as the distinguishing difference between B. s. subtilis and B. s. spizizenii. However, a comparative genomic analysis of B. subtilis spp. revealed that both B. s. subtilis and B. s. spizizenii had various types of cell walls. These tar and tag operons were mutually exclusive and the tar genes from B. s. spizizenii were very similar to the genes from non-Bacillus bacteria, unlike the tag genes from B. s. subtilis. The results and previous studies suggest that the tar genes and the tag genes are not inherited after subspecies speciation. The phylogenetic tree based on whole genome sequences showed that each subspecies clearly formed a monophyletic group, while the tree based on tar genes showed that monophyletic groups were formed according to the cell wall type rather than the subspecies. These findings indicate that the tar genes and the presence of ribitol as a cell-wall constituent were not the distinguishing difference between the subspecies of B. subtilis and that the description of subspecies B. s. spizizenii should be updated.