In this study, the characteristics of wind pressure distribution on circular retractable dome roofs with a low rise-to-span ratio were analyzed under various approaching flow conditions by obtaining and analyzing wind pressures under three different turbulent boundary layers. Compared to the results of previous studies with a rise-to-span ratio of 0.1, it was confirmed that a lower rise-to-span ratio increases the reattachment length of the separated approaching flow, thereby increasing the influence of negative pressure. Additionally, it was found that wind pressures varied significantly according to the characteristics of the turbulence intensity. Based on these experimental results, a model for peak net pressure coefficients for cladding design was proposed, considering variations in turbulence intensity and height.

In this study the characteristics of wind pressure that are depending on the open type of retractable dome roof were analyzed according to the wind pressure coefficient and wind pressure spectrum. The analysis results showed that the open type and shape of the roof both had a significant impact on the wind pressure changing. In case of the edge to center open type, the wind pressure has not changed much because of the complex turbulence of flow and open area. On the other hand, in case of the center to edge open type, it has confirmed that wind pressure increases due to the separation of flow in windward and open area.

The fluctuating wind pressure of the low rise ratio(f/D=0.1) for the elliptical dome roof was analyzed to compare it with the previous studies of circular dome roofs. Wind tunnel test were conducted on a total of 10 wind directions from 0° to 90° while changing wall height-span ratios(H/D=0.1-0.5). For this, meanCP, rmsCP and wind pressure spectrum were analyzed. The analysis result leads to find differences in the shape of the spectra in the spanwise direction and leeward of the elliptical dome according to the wind direction variations of the elliptical dome roof.

Wind tunnel tests were conducted to analyze the wind fluctuating pressures on a circular closed and open dome roof with a low span rise. Two dome models with various geometric parameters (height/span ratios and open ratios) were used for fixed span rise ratio dome and wind pressure spectrum were analyzed. The applicability was examined in comparison with the spectral model proposed in the previous studies. The analysis results show that the wind pressure spectrum of open dome roof tends to increase power in the high frequency range and the second peak is found in the area different from the closed dome roof. In addition, according to the comparison analysis with the previous proposed spectral model, it was found that it is not applicable to the closed and open dome roofs with low rise ratio due to the different peak frequencies.

In this paper, the mean and fluctuating pressure coefficients derived from the results of wind tunnel tests on closed and open dome roofs were analyzed. The distribution characteristics of the fluctuating pressure according to the opening ratio and the height change were discussed. The analysis results showed that when the roof is open, the overall wind pressure decreases due to the open space, but more fluctuation occurred than the closed dome roof.

This study investigates the wind pressure characteristics of elliptical plan retractable dome roof. Wind tunnel experiments were performed on spherical dome roofs with varying wall height-span ratios (0.1~0.5) and opening ratios (0%, 10%, 30% and 50%), similar to previous studies of cirular dome roofs. In previous study, wind pressure coefficients for open dome roofs have been proposed since there are no wind load criteria for open roofs. However, in the case of Eeliptical plan retractable dome roof, the wind pressure coefficient may be largely different due to the presence of the longitudinal direction and transverse direction. The analysis results leads to the exceeding of maximum and minimum wind pressure coefficients KBC2016 code.

선충포식성 곰팡이는 선충을 포획하기 위하여 다양하고 특수한 기관을 사용한다. 국내 성주지역의 참외 경작지 뿌리 주변의 토양에서 3차원 접착 고리를 형성하여 선충을 포획하는 곰팡이를 분리하였다. 곰팡이의 미세형태 구조를 관찰한 결과 분생포자병은 직립형으로 길이는 290~528 (342.8) μm으로 길었으며, 계란형의 30.5 × 20.3 μm 크기를 가진 1~3개의 분생포자를 형성하였다. 균주의 rDNA의 5.8 S 영역의 염기서열을 분석한 결과, Arthrobotrys속의 계통군에 속하였으며, 특히 Arthrobotrys sinensis와 99%의 유사성을 보였다. 형태적 특징과 분자생물학적 계통 분석을 바탕으로 본 균주는 A. sinensis로 확인되었으며, 이는 국내 미기록종으로 식물기생성선충의 생물학적 조절을 위한 하나의 자원이 될 수 있다.

한국 최초의 서양화가인 고희동의 회화는 1920년대 중반 서양화에서 전통회화로 회귀하였다. 이 논문에서는 그가 서양화에서 전통회화로 회귀하게 된 과정을 검토한 다음 전통회귀 이후 그가 남화가로 분류된 사실에 주목하여 그 배경과 의미를 규명하였다. 고희동의 회화가 전통으로 회귀한 이후 조형표현에 나타난 특징은 두 가지 즉, 서양화법의 특징을 도입하여 절충적인 특징을 드러내거나 관념산수의 전통을 이으며 필선 중심의 묘사나 단일시점이 아닌 분절적인 시점을 설정하는 특징을 보였다. 특히 1940년대에 고희동이 조선남화연맹의 창립 회원으로서 활동하며 이상범, 노수현, 변관식 등과 함께 남화가로 활동한 사실은 그의 전통회귀가 일본인의 동아시아회화사 인식에 바탕을 둔 남화를 그리는 화가로 분류되었음을 의미한다.

The biggest impact on the cladding design of buildings is wind loads. Wind tunnel tests were conducted to examine the applicability of current wind load standards about membrane retractable roof spatial structure. A dome model with a circular shape that is retractable to the center of the dome was made (Opening ratio = 0, 10, 30, 50). In addition, height adjustable turntables were made and tested with five patterns with H/D = 0.1, 0.2, 0.3, 0.4 and 0.5. The maximum wind pressure coefficient and the minimum wind pressure coefficient for the cladding were analyzed and the experimental wind pressure coefficient were compared with the current wind load standards, KBC2016 and AIJ-RLB(2015). The experimental value and the reference value of the enclosed roof were very similar and showed possibility of application, but opened roof case was found that the reference value was underestimated.

The identification of damping ratios in buildings is a well-known problem and appears to be of important and crucial interest in the safety and serviceability design. When compared to an estimation of the stiffness, i.e. natural frequency, and mass, the damping ratio is the most difficult quantity to determine. Many previous studies have examined the characteristics of damping ratios from ambient vibration, but the measurement time is roughly within 2 hours. In this paper, characteristics of damping ratios and natural frequencies of 4 story RC building were investigated using long-term ambient vibration. Free vibrations were obtained using random decrement technique, and damping ratios were evaluated by the envelop function, continuous wavelet transform, and logarithmic decrement. It was found that although the natural frequencies show little variations with time, the damping ratios show some variations with time and the largest variations found in the damping ratios obtained from the continuous wavelet transform. The damping ratios from the envelop function showed the smallest mean and standard deviation. And the probability distribution of damping ratios seems to follow the logarithmic normal distribution.

Vortex-induced vibration and instability vibration of tall buildings are very important fluid-structure interaction phenomenon, and many fundamental questions concerning the influence of body movement on the unsteady aerodynamic force remain unanswered. For tall buildings, there are two experimental methods to investigate the characteristics of unsteady aerodynamic forces, one is forced vibration method and the other is free vibration method. In the present paper, a free vibration method was used to investigate the unsteady aerodynamic force on tall building whose aspect ratio is 9 under boundary layer simulating city area. Wind pressures on surfaces and tip displacements were measured simultaneously, and the characteristics of tip displacements and generalized forces were discussed. It was found that variation of across-wind displacements showed different trend between the case when wind speed increases and wind speed decreases, and the fluctuating generalize forces in across-wind direction of vibrating model are larger than that of static model near the resonant wind speed and approach to the static value. And for higher wind speed range, there were two peaks in across-wind power spectra of generalize forces of vibrating model, which means that two frequency components are predominant in unsteady aerodynamic forces.

Aerodynamic performance of solar wing system has been evaluated through wind tunnel test. The test model has 12 panels, each supported by 2 cables. The panels were installed horizontally flat, and gaps between panels were set constant. Sag ratios of 2% and 5%, and wind directions between 0° and 90° were considered. Mass of test model was determined considering the mass of full scale model, and Froude number and Elastic parameter were satisfied by adjusting the mean wind speed. From the wind tunnel test, it was found that the aerodynamic performance of the solar wing system is very dependent on the wind directions and sag ratios. When the sag was 2%, the fluctuating displacements between the wind directions of 0° and 30° increase proportionally to the square of the mean wind speed, implying buffeting-like vibration and a sudden increase in fluctuating displacement was found at large mean wind speed for the wind directions larger than 40°. When the wind direction was larger than 60°, a sudden increase was found both at low and large mean wind speed. When the sag ratio is 5%, distribution of mean displacements is different from that of sag ratio of 2%, and the fluctuating displacements show very different trend from that of sag ratio of 2%.

순환식 수막시스템의 적정 수온을 결정하는데 필요한 기초자료를 제공하기 위하여 딸기를 토경재배하고 있는 실험온실에서 외부온도, 수막용수의 수온 및 야간시간대에 따른 처리방식별 온실 내부 환경변화를 비교 분석하였다. 대조구는 무수막 온실이고, 처리구는 수온이 10oC, 15oC로 각각 설정된 순환식 수막온실로서 모두 무가온 및 추가적인 보온자재의 투입이 없는 상태를 말한다. 수막이 직접 살수되는 2중 비닐하우스는 폭 5.5m, 길이 55m이고, 분당 살수되는 평균 수막유량은 38.5~44.5L로 나타났다. 3가지 처리조건 모두에서 외부온도와 내부온도는 양의 선형관련성이 매우 높게 나타났으며 처리구 (10, 15oC)의 외부온도에 대한 상관성은 유사한 수준으로 분석되었다. 보온효과는 수온 15oC 처리구가 수온 10oC 처리구보다 1.3oC 정도 우수한 것으로 나타났다. 외부온도가 약 -8.1~8.6oC 범위에서 변화할 때, 처리조건 별 최저온도는 무처리구, 수온 10oC 처리구, 수온 15oC 처리구가 외부에 비해 각각 6.4, 11.0, 12.3oC 정도 높게 유지되는 것으로 나타났다. 평균 온도는 무처리구, 수온 10oC 처리구, 수온 15oC 처리구의 순으로 높아지고 온도변화폭은 오히려 작아지는 경향을 보였다. 외부 최저 온도가 -1.3oC, 평균온도가 1.5oC인 날은 수막시스템의 수온을 10oC로, 외부 최저온도가 -4.7oC, 평균온도가 -0.2oC 인 날은 수온을 15oC로 설정해도 온실의 목표온도(5oC) 유지가 가능한 것으로 나타났다. 처리조건별 야간시간대( 일몰 후, 자정, 일출 전, 일출 후)에 따른 온실 내부와 외부의 온도는 전반적으로 일몰직후가 가장 높고, 이후 서서히 감소하여 일출직전이 가장 낮아지는 경향을 보였다. 따라서 온실의 목표온도 유지를 위해서는 일출직전 시간대에 특히 집중적인 관리가 필요하며, 순환식 수막 시스템의 수온을 획일적으로 15oC 이상으로 결정하기 보다는 외부온도 변화, 야간시간대, 재배작물에 따라 다르게 결정하는 것이 타당한 것으로 판단된다.

식물기생성선충으로 인한 피해를 경감시키고 예방하기 위한 방안으로 본 연구는 고추 시설하우스 재배지역의 토양 내 선충 발생 양상과 분포 및 밀도 조사를 하였다. 밀양시 부북면, 무안면 그리고 상남면의 고추 시설재배 32 농가의 56개 하우스로부터 71점의 토양 샘플을 수집하여 고추 재배 연작 연수 및 고추 재배 시기 등에 따른 식물기생선충의 분포와 밀도를 비교 분석하였다. 농가의 방제제 사용으로 인하여 고추 재배 연작 연수와 선충 밀도와의 유의성은 없었다. 선충의 발생 양상은 뿌리혹선충, 참선충, 둥근꼬리선충, 창선충, 위축선충 그리고 부식성선충을 포함한 기타 선충이 검출되었다. 식물기생성 선충들 중 뿌리혹선충의 밀도가 가장 높았다. 밀양시 고추 시설재배지 중 부북면, 무안면, 상남면의 순으로 뿌리혹선충의 밀도가 높은 경향을 나타내었다.

국내 콩 재배 품종에 대한 선충 저항성 분석 및 국내외 유전자원 수집과 분석을 통하여 콩 씨스트 선충 피해 경감과 씨스트 선충 저항성 품종 육성 자료로 활용하고자 본 연구를 진행하였다. 국내 콩 재배품종인 75개의 자원에 대한 저항성 분석 결과 번식이 가장 적었던 품종은 장엽콩이며, 장엽콩, 새알콩, 밀양콩, 만수콩 등 4품종은 중간저항성을 나타냈으며, 알찬콩 등 33품종은 중간감수성을, 38품종은 감수성을 나타내었다. 기 보고된 콩 씨스트 선충 유전자(rhg1, rhg2, rhg3, Rhg4)를 이용한 분자생물학적 분석을 통하여 국내 품종 10품종과 HG-type에 이용되는 Lee74를 포함한 8가지 품종을 이용한 분석 결과 유전자의 유무차이가 아닌 것으로 나타났으며, sequence분석 결과 SNP차이를 확인하였고 단백질 분석 결과 rhg1 gene의 Leucine Rich Region(LRR) domain 부근에서 감수성과 저항성의 차이가 나타났으며, 콩 씨스트 선충 저항성 유전자인 rhg1의 경우 감수성에서 나타나는 차이가 3가지(H474R, R475K, K476N)가 있으며, rhg2의 경우 감수성에서 나타나는 3가지(I114F, I266N, P277L) 및 저항성에서 다르게 나타나는 2개의 G281S와 S292C 단백질 발견하였다. 본 연구를 통하여 콩 씨스트 선충 저항성 품종과 감수성품종 구분을 위한 marker로 활용 가능한 primer를 작성하였고 콩 씨스트 선충 저항성 품종 육성 자료로 이용될 수 있을 것이다.

A series of wind tunnel tests were conducted on 7 super-tall buildings with various polygon cross-sections, including triangle, square, pentagon, hexagon, octagon, dodecagon, and circular. The primary purpose of the present study is to investigate the effect of increasing number of sides on aerodynamic characteristics for super-tall buildings. Wind tunnel tests were conducted under the turbulent boundary layers whose power-law exponent is 0.27. Fluctuating wind pressures from more than 200 pressure taps were recorded simultaneously, and time series of overturning moments were calculated considering tributary area of each pressure tap. The results show that the overturning moment coefficients and the spectral values decrease with increasing number of sides, and the largest mean and fluctuating overturning moments were found for the triangular super-tall building, and the largest spectral values were found for the square super-tall building. The analysis should be conducted more in detail, but currently it can be roughly said that there seems to be a little differences in the aerodynamic characteristics for the super-tall buildings whose number of sides is larger than 5 or 6.

Recent tall buildings tend to have unconventional shapes as a prevailing, which is effective for suppressing across-wind responses. Suppression of across-wind responses is a major factor in tall building projects, and the so called aerodynamic modification method is comprehensively used. The purpose of the present study is to investigate the pressure fluctuations on tapered and setback tall buildings, including peak pressures, power spectra and coherences through the synchronous multi-pressure sensing system techniques. And flow measurements around the models were conducted to investigate the condition of vortex shedding. The results show that by tapering and setback, different distributions of mean pressure coefficients at leeward surface were found, which is caused by the geometric characteristics of the models. And the power spectra of wind pressures at sideward surface become wideband and the peak frequencies are different depending on heights, which makes the correlation near the Strouhal component low or even negative. The differences in shedding frequencies were also confirmed by the flow fields around the models.

For most of recent tall buildings, one characteristic is that their building shapes vary with height such as taper and setback, and this implies that the distribution of their structural components may also vary with height. Because of these structural variations, although the sectional shapes of these buildings are symmetric, it is difficult to say whether or not they are structurally symmetric. The acceleration responses of structurally asymmetric tall buildings are larger than those of non-eccentric buildings, thus raising the possibility of problems during strong winds and typhoons. This paper describes wind tunnel tests carried out using building models with height variations and acceleration response analyses, and discusses the resulting response characteristics. For tapered and setback buildings, although the across-wind accelerations are larger than those of a square building, the total root-mean-square accelerations remain small because of smaller along-wind and torsional rms accelerations. And it was found that the effects of statistical couplings between along-wind force and other two forces are negligible.