The performance of ground-based optical structures is highly sensitive to external environments, such as airflow in open space. In this paper, initial aerodynamic data due to ambient air flow were analyzed in optical models designed through knowledge-based design algorithm, and dynamic data acting on optical structures in turbulent flow with velocity of 50m/s were analyzed to present the initial shape design conditions of the structures. The simulation results showed that the maximum pressure, minimum pressure, and maximum differential pressure acting on the mirror are directly proportional to the sweep angle.

The purpose of this study is to suggest structural model and analyze design factors for the development of small greenhouse standardization model. The average dimensions of small greenhouse desired by urban farmers were 3.3m in width, 1.9m in eaves height, 2.7m in ridge height, 5.7m in length. The cladding materials for small greenhouse were preferred to glass, PC board and plastic film, framework to aluminum alloy and steel, and heating method in electrical energy. In addition, it was analyzed that small greenhouses need to develop structural model by dividing them into entry-level type and high-level type. The roof type that was used for entry-level type was arch shape, framework was steel pipe, cladding material was plastic film. On the other hand, high-level type was used in even span or dutch light type, framework with square hollow steel, cladding materials with glass or PC board. In consideration of these findings and practicality, this study developed four types of small greenhouses. The width, eaves height, ridges height, and length of the small greenhouses of even span type, which were covered with 5mm thick glass and 6mm thick PC board were 3m, 2.2m, 2.9m, and 6m, respectively. The small greenhouse of dutch light type covered with 5mm thick glass was designed with 3.8m in with, 2.2m in eaves height, 2.9m in ridges height, and 6m in length. The width, eaves height, ridges height, and length of the arch shape small greenhouse covered with a 0.15mm PO film were 3m, 1.5m, 2.8m, and 6m, respectively.

본 연구에서는 대면적을 지니는 CDI 모듈의 흐름 향상을 위하여 유체가 들어가는 유입구로부터 면적이 증가하는 직사각형 형태의 유로를 설계하였다. 이를 바탕으로 설계된 모듈 형태에 대해 공급수의 흐름성과 사영역의 유무를 파악하였고 CFD 전산 유체 역학 프로그램을 통해 유로 내의 내부 압력, 유선 그리고 속도 벡터 분포를 분석하였으며 실제 흐름 관측과 CFD 프로그램을 비교 분석하였다. 실험 결과 모든 유속 10, 20, 30 mL/min에서 유로 내 사영역이 거의 발생하지 않았으며 공급수의 흐름성도 일정하게 유지되어 추후 대면적을 가지는 CDI 공정에 적용이 가능할 것이라 판단된다.

These days, costumes of Korean creative dancing performances have been changed to be modernized and to be out of traditional regulation, as the representation of the Korean styles were replaced by other props and art devices. In this article, we have applied the emotions expressed in Jin-Yi Hwang’s sijos (Korean traditional poems), to Korean creative dancing costumes in modern style. chose three typical sijos from her six pieces, titled “Green mountain is like what I’ve meant”, “To Byeokgyesoo in Cheongsan-ri” and “Dongjibam ginaginbam”. In brief, Jin-Yi Hwang expressed her “everlasting love and emptiness”, “temptative conciliation” and “eager waiting” these three sijos, respectively. The character of Jin-Yi Hwang was shown in many TV soap operas and films, and the costumes were either much modernized, and not accurately based on the sijos she had written. Thus, we designed, made flat sketched, and fabricated three Korean creative dancing costumes from the three sijos, listed. We tried to highlight the aesthetic impression and the activeness of the dancing costumes, using both traditional and modern Korean fabrics. Since Korean dance costumes had not yet been inspired from Jin-Yi Hwang’s sijos, we discussed the importance of the fabric items, as well as the visual, auditory, and tactile characteristics of the costumes and dancers to emphasize Jin-Yi Hwang’s expressed emotions.

The purpose of this study is to provide basic data for setting environmental design standards for domestic greenhouses. We conducted experiments on thermal environment measurement at two commercial greenhouses where hot water heating system is adopted. We analyzed heat transfer characteristics of hot water heating pipes and heat emission per unit length of heating pipes was presented. The average air temperature in two greenhouses was controlled to 16.3oC and 14.6oC during the experiment, respectively. The average water temperature in heating pipes was 52.3oC and 45.0oC, respectively. Experimental results showed that natural convection heat transfer coefficient of heating pipe surface was in the range of 5.71~7.49W/m2 oC. When the flow rate in heating pipe was 0.5m/s or more, temperature difference between hot water and pipe surface was not large. Based on this, overall heat transfer coefficient of heating pipe was derived as form of laminar natural convection heat transfer coefficient in the horizontal cylinder. By modifying the equation of overall heat transfer coefficient, a formula for calculating the heat emission per unit length of hot water heating pipe was developed, which uses pipe size and temperature difference between hot water and indoor air as input variables. The results of this study were compared with domestic and foreign data, and it was found to be closest to JGHA data. The data of NAAS, BALLS and ASHRAE were judged to be too large. Therefore, in order to set up environmental design standards for domestic greenhouses, it is necessary to fully examine those data through further experiments.

Several water tanks installed in the building were damaged during the Gyeongju earthquake (2016) and the Pohang earthquake (2017). Since a water tank for fire protection is very important component, seismic safety should be ensured. In this study, an interaction between a water tank and a building was studied by the dynamic analysis of the RC building with the water tank. In case the water tank was installed on the roof of the RC building, it was confirmed that it did not significantly affect the response of the building. Based on the result, dynamic response characteristics of the water tank in the building were studied using two SDOF models represented dynamic behavior of the water tanks under earthquake. An earthquake time-history analysis was carried out with variables of aspect ratio of the tank, story of the building, and installed location in the building using three kinds of earthquakes.

In this paper, a pico hydro turbine employing low head circulation water at fish farms is designed and evaluated. Due to the advantages of simple structures, small head requirements, and low-cost investment, the constant thickness propeller turbine is considered as a feasible solution. The design process based on the free vortex method is presented in full detail, and a 4-blade runner is built using BladeGen. The turbine performance is analyzed both numerically and via experimental methods. Despite slight differences, the results show similar trends between CFD simulations and experiments carried out on factory test-rigs in a wide range of working conditions. At the design flow rate, the turbine achieves the best efficiency of 70 %, generating 3.5 kW power when rotating at 420 rpm. The internal flow field, as well as the turbine's behavior, are investigated through the distribution of blade streamlines, pressure, and velocity around the runner. Moreover, the pressure coefficient on the blade surface at 3 span positions is plotted while the head loss for each simulation domain is calculated and displayed by charts.

본 연구의 목적은 In-DEBS (In-situ Demonstration of Engineered Barrier System) 시험장치에 대한 설계안을 도출하고, 현장실증용 공학적방벽재의 생산을 위한 최적 제작조건을 도출하는 것이다. 이와 관련하여 그간 한국원자력연구원에서 수행한 실증실험 수행경험과 문헌분석 그리고 선진핵주기 고준위폐기물처분시스템(AKRS)을 근거로 시험장치를 설계하였다. 또한 처분용기와 벤토나이트 완충재는 시험제작을 통해 최적의 제작조건을 도출하였고, 예비 성능평가를 통해 제작된 공학적방벽재의 성능을 검증하였다. In-DEBS 현장시험을 위해서 AKRS의 1/2.3 규모로 설계하였으며, 고른 온도분포의 핵연료 모사를 위하여 설계 전력량 4.2 kW의 알루미늄 재질 몰드히터를 사용하였다. 한편 In-DEBS에 사용될 공학규모 이상의 균질 완충재 블록을 제작하기 위해 플롯팅 다이(floating die) 방식의 프레스 재하 및 냉간등방압프레스(CIP; Cold Isostatic Press) 기법을 국내 최초로 완충재 제작에 적용하였다. 연구결과 AKRS 완충재 블록 제한요건(건조밀도 › 1.6 kg·cm-3)을 충족하기 위해서는 1차로 40 MPa 이상의 플롯팅 다이 프레스 압력을 가하고, 2차로 50 MPa의 CIP 압력이 소요됨을 확인하였다. 또한 완충재 블록 내 센서설치를 위하여 CNC (Computer Numerical Control) 기법을 이용하여 센서위치를 정교하게 성형하였다

In this theoretical study, a design and performance analysis theory of a micro flowrate and high pressure air-compressor is developed. The governing equations are from the gas state equation and fluid dynamic theories because the working fluid in the air compressor is in a gas phase. A case study was conducted to design a reciprocating type of air compressor which the target performance was 0.6liter/min in the volume flowrate with 5atg in air pressure at 1,600rpm rotational speed. Geometrical size of the model air compressor designed is 10mm in stroke, 20mm in bore with 4.79 compression ratio. From the performance analysis of the model compressor, it was found that the air volume flowrate produced was 0.6liter/min with 5.81atg in pressure. The design theory of a micro-size high-pressure air compressor developed in this study is expected to be very useful design tools in NANO technology industry.

In the modern industrial period, the introduction of mass production was most important progress in civilization. Die-casting process is one of main methods for mass production in the modern industry. The aluminum die-casting in the mold filling process is very complicated where flow momentum is the high velocity of the liquid metal. Actually, it is almost impossible in complex parts exactly to figure the mold filling performance out with the experimental knowledge. The aluminum die-castings are important processes in the automotive industry to produce the lightweight automobile bodies. Due to this condition, the simulation is going to be more critical role in the design procedure. Simulation can give the best solution of a casting system and also enhance the casting quality. The cost and time savings of the casting layout design are the most advantage of Computer Aided Engineering (CAE).. Generally, the relations of casting conditions such as injection system, gate system, and cooling system should be considered when designing the casting layout. Due to the various relative matters of the above conditions, product defects such as defect extent and location are significantly difference. In this research by using the simulation software (AnyCasting), CAE simulation was conducted with three layout designs to find out the best alternative for the casting layout design of an automotive Oil Pan_BJ3E. In order to apply the simulation results into the production die-casting mold, they were analyzed and compared carefully. Internal porosities which are caused by air entrapments during the filling process were predicted and also the results of three models were compared with the modifications of the gate system and overflows. Internal porosities which are occurred during the solidification process are predicted with the solidification analysis. And also the results of the modified gate system are compared.

도시의 인구가 증가함에 따라 도시민의 여가 공간으로 활용되는 도심지 공원의 중요성이 가중되고 있다. 그러나 과도한 인구 밀집으로 인한 공원 이용객의 증가는 도시공원 내 범죄 발생 증가로 이어지고 있으며, 이러한 공원 내의 범죄율은 매년 증가하는 추세를 보이고 있다(경찰청통계, 2012). 특히 최근에는 시체유기와 같은 강력범죄 또한 증가 하고 있는 실정으로, 사회적 관심 공간으로서 재조명되고 있다(김석진과 박미량, 2013). 이에 환경개선을 통한 범죄 예방설계(CPTED)기법 5원칙(자연적 감시, 접근통제, 영역 성, 활용성, 유지관리)이 적용된 공원설계 지침 등이 등장하였으며, 이 같은 범죄예방설계 기법이 조경 설계 및 공원설계에 적용됨에 따라 최근 범죄예방설계의 적용 및 실증분석 연구가 진행되고 있다. 공원의 범죄예방설계 연구로는 기존 도시와 건축물에 적용되던 범죄예방설계를 공원에 적용하기 위한 지침계선 연구가 주를 이루었으며, 이에 대한 실증분석을 통해 공원 내 실효성이 있는 범죄예방설계를 제시하는 연구가 주를 이루어 진행되고 있다. 반면 공원 중 규모가 큰 소공원이나 근린공원의 경우 안전에 대한 인식과 요구도가 높아 공원 내 폐쇄 회로 텔레비전(CCTV)과 비상벨 등 다양한 범죄예방설계 요소에 대한 실증분석 연구가 다수 진행되고 있는 반면 어린이 공원의 경우 범죄예방설계 관련 연구가 다소 미비한 실정이다. 특히 어린이 공원의 경우 사회적 약자의 이용이 잦기 때문에 더욱이 안전성 확보가 절실한 실정이다. 이에 본 연구는 상대적으로 범죄예방설계에 대한 연구가 부족한 어린이공원을 중심으로 실사용자의 설문을 통해 요구도와 이용자평가를 분석하여 어린이공원에 직･간접적으로 필요한 범죄예방설계 요소를 도출하였으며, 이를 통해 어린이 공원의 범죄예방설계 적용 및 관리를 위한 보완사항 및 개선방안을 제시하고자 하였다. 어린이공원의 사용자 설문을 위한 대상지는 충청북도 충주시 어린이공원 12곳을 선정하였으며, 설문지의 경우 리커트 척도의 5점 척도를 사용하여 체크리스트와 이용자평가 를 조사하였다. 분석을 위한 체크리스트와 이용자평가는 범죄예방설계 원리를 중심으로 자연적 감시 7문항, 접근통제 및 영역성 6문항, 활용성 7문항, 유지관리 3문항으로 20문항이었으며, 수집된 설문지를 통해 요구도 분석과 이용자평 가를 진행하였다. 이용자 평가를 통한 범죄예방설계의 요구도 분석결과 자 연적 감시의 경우 휴게공간과 놀이 공간의 시야 확보가 가장 필요한 것으로 분석되었으며, 가로등에 의한 빛 차단에서 가장 낮은 요구도를 보였다. 접근통제 및 영역성의 경우 CCTV의 사각지대가 가장 요구도가 높게 분석되었으며, 지름길의 유･무가 가장 낮은 것으로 분석되었다. 활용성의 경우 휴식공간의 그늘 조성이 가장 중요한 것으로 분석되었고 생태성 증진이 다소 낮은 경향을 보였다. 유지관리의 경우 공원의 청결한 환경에서 요구도가 가장 높은 것으로 분석되었으며, 공원 내 잡초 관리가 낮은 요구도를 보였다. 이용자 평가의 경우 자연적 감시에서 시야 확보가 가장 잘 되어 있다고 평가하였으며, 가로등의 빛 차단을 가장 낮게 평가하였다. 접근통제 및 영역성은 공원경계의 명확성이 잘되어 있다고 응답하였으며 음주 및 흡연 통제가 가장 안 되어 있다고 응답하였다. 활용성의 이용자 평가 분석결과 휴식공간의 그 늘 조성이 잘되어 있다고 응답하였으며, 조경요소의 만족도 가 낮은 것으로 분석되었다. 유지관리의 경우 시설물의 유지 관리가 잘 되어 있다고 응답하였으며, 공원의 청결성이 결여 되어 있다고 응답하였다. 전반적으로 남성보다 여성의 요구도가 높았으며 현장평가에서도 낮은 점수를 부여했다.

온실 냉난방시스템 설계용 외부기상조건의 분석 기준을 설정하기 위하여 연간 백분위 방식에 의한 냉난방 설계기온을 분석하고, 기존의 계절 백분위 방식에 의한 설계기온과 비교 검토하였다. 우리나라 전 지역을 대상으로 현재 기상청에서 제공하는 기후평년값 기준 30년간의 매 시각 기상자료를 분석에 사용하였다. 표준기상 데이터의 이용이 제한적이기 때문에 전체 기상자료를 이용하여 매년 설계용 기상조건을 구하고, 전체 자료기간의 평균값을 분석에 사용하였다. 연간 백분위 방식으로 1년 기준 총 8,760시간의 백분위수 0.4%, 1%, 2%를 냉방 설계 외기온으로, 99.6%, 99%를 난방 설계 외기온으로 제시하였다. 연간 백분위 방식을 채택할 경우 계절 백분위 방식에 비하여 전체적으로 난방설계 외기온은 6.7~9.6% 상승하는 것으로 나타났으며, 냉방설계 외기온은 0.6~1.1% 하강하는 것으로 나타났다. 동일한 온실 조건에서 최대난방부하는 연간 백분위 방식을 채택할 경우 기존의 계절 백분위 방식에 비하여 약 3.0~3.6% 정도 감소하는 것으로 나타났고, 최대냉방부하에 미치는 영향은 미미한 것으로 분석되었다. 따라서 난방설계 외기온은 연간 백분위 방식으로의 변경에 대하여 고려할 필요가 있지만, 냉방설계 외기온은 두 방법 간의 차이가 거의 없으므로 아직까지 변경할 필요는 없는 것으로 판단된다. 전체적으로 현재의 계절 백분위 방식으로 분석한 설계 외기온을 사용하여도 큰 문제는 없을 것으로 생각되지만, 기후변화의 영향을 고려하여 주기적인 설계용 기상자료의 분석 및 설계기준의 개정이 필요하고, 현재의 기후평년값 기준연도가 바뀌는 2021년 이후에는 이 기간의 기상자료를 분석하여 새로운 설계기준으로 제공해야 할 것이므로, 그 때 연간 백분위 방식에 대한 전문가 그룹의 검토를 통하여 반영할 필요가 있을 것으로 판단된다.

In this study, we analyzed the whole design of the necklace in detail, which reflects the artistic sense of handicraft in couture. The purpose of the study was to identify the characteristics of the design based on the analysis findings and to provide basic data to help fashion designers. The research method entailed analyzing trends in necklace design - viewed in fashion magazines and on websites - by year, season, brand, kind, material, color, and image. The identified necklace design characteristics were as follows. First, artistry and originality are dramatically expressed through the use of a broad range of materials. Second, due to the necklace’s role as an object of perfect beauty, in a number of images, the necklaces were presented in convergence and contrast with overall costumes. Third, the dramatic effects of layering revealed a strong presence and individualized styling. Necklaces are created with diverse sculptures by realizing the creative imagination of fashion designers. Even though they looked a little different every year, there were designs in the collections constantly. Round shape and princess length were preferred. In particular, the mix type was used to express dramatic effect by focusing neck part in entire styling which different length of necklaces were layered and worn. As a result, it meets the needs of consumers who emphasize brand differentiation and diversity, and it is believed that the role of necessities in fashion will continue and it creates economic demand in the fashion industry.