• 한국태양에너지학회 논문집
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• 제31권6호
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• pp.103-110
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• 2011

The aim of this study was to analysis the Heating/cooling performance and Daylighting performance of Solar Window System built in apartments. the solar window is the idea to integrate daylight as a third form of solar energy into a PV/Solar Collector system. The process of this study is as follows: 1)Solar Window system was designed through the investigation of previous paper and work. 2)The simulation program(Lightscape3.2) was used in daylighting performance analysis. the reference model of simulation was made up to analysis daylighting performance on Solar Window system. 3)The simulation program(ESP-r, Therm5.0, Window6.0) was used in energy performance analysis. the reference model of simulation was made up to analysis energy and daylighting performance on Solar Window system. 4)The Size of Simulation model for daylighting and heating/cooling energy analysis was $148.5m^2$ 5)The lighting performance analysis was carried out with various variants, such as the size and installed area of Solar Window system. 6)Energy performance simulation was carried out with various variants, such as Integrated U-value of Solar Window system according to its position, installed angle and insulation thickness. Consequently, When Solar Window system is equipped with balcony window of Apartment, Annual heating and cooling energy of reference model was cut down at the average of $4.1kWh/m^2$ or 4.2%.

• 보건교육건강증진학회지
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• 제31권5호
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• pp.109-120
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• 2014

Objectives: This study was to examine the associations between obesity level and major chronic diseases in older population in Korea, using different obesity indicators. Methods: Data was from the 2008 KloSA Biomarker pilot, a nationwide sample of 514 non-institutionalized subjects (age $63.6{\pm}9.8$ years; women 57.2%). Anthropometric information was collected by home visiting nurses. Portable bioimpedence devices(Omran HBF359) were used for measuring fat mass. Obesity cut-offs used the Asian criteria of $BMI{\geq}25$, $WC{\geq}90/85cm$, and $fat%{\geq}25/35$ for men and women. Chronic disease prevalence was defined by physician-diagnosed history of 8 specified diseases. Results: Prevalence of chronic diseases significantly increased with increment of obesity level by BMI, WC and fat %. Odds ratios of acquiring chronic diseases remained significant in the obese group (BMI OR 2.76, 95%CI 1.82-4.19; WC OR 2.73, 95%CI 1.81-4.11; Fat OR 1.87 95%CI 1.26-2.78), after adjusting for age, sex, marital status, education, work participation, household income, smoking, drinking, and exercise. Conclusions: Obesity measured by all three indicators, BMI, WC, and fat mass cannot be disregarded, accentuating the significant effect on increases in disease risks among older population. BMI and WC measure appeared better to assess the risks of chronic diseases.

• 한국환경과학회지
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• 제16권6호
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• pp.735-743
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• 2007

A grouting method is the way to effectively prevent pollutants from spreading into the ground during the digging process of groundwater. This study, based on the comparative study of grouting methods being generally accepted, suggests various construction methods which are suitable for geological structure as follows: In Jeju Island, it is very likely that rocks may fall in shuttered zones such as cracks, joints, scoria layers, and clinker layers. For this reason, it is recommended that materials be injected from the bottom toward the top, not from the top to the bottom. In the case where the amount of injected materials become too large in the areas of cracks or joints because of high level of permeability coefficient, grouting materials which smeared into surrounding areas may cause unwanted cut in the aquifer of the bottom level. To avoid this, the amount of water should be reduced from the typical water-cement ratio of 1:2, and grouting materials with larger grading should be used. If the deep excavation of ground is made in Jeju Island, it is likely to have lots of voids because of geological characteristics. Based on the results of this research, it is found that to construct interior casing, the centralizer should be attached to the casing to prevent the casing from being in contact with the counter fort. The grouting in Jeju Island should be thicker than usual. To avoid over-use of grouting materials, to prevent grouting in more than necessary zone, and to facilitate grouting of void areas, the flexible selection of materials is required. And, to exactly figure out the interior of dug well, an examination through CCTV should necessarily be performed when grouting work is in progress.

• 한국항해항만학회지
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• 제31권10호
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• pp.905-910
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• 2007

최근에 선박이 대형화, 고속화되면서 선수 충격파 영향으로 인하여 선체 또는 화물에 잦은 손상을 초래하기도 하고, 극판적인 상황에서는 선박이 절단되기도 한다. 본 논문에서는 내항성능 평가요소 중 하나인 상하가속도 값을 선교에 설치된 선체감시장치를 이용하여 해상상태별 변화량을 계측하고, 이를 모형시험 및 이론계산 결과와 상호 비교하였다. 또한 ITTC에서 제시하는 내항성능 기준치와도 비교함으로써 실습선 한바다호의 내항성능을 확인하였다. 이러한 결과는 앞으로 경험할 수 있는 다양한 해상상태에서의 작업가능성 및 위험성 정도의 예측을 가능하게 함으로써 선박의 안전운항에 큰 도움이 될 것으로 판단되며, 또한 다양한 실선계측 자료를 통하여 조선소에서는 보다 우수한 성능의 선박 건조가 가능하리라 본다.

• 한국환경복원기술학회지
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• 제15권1호
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• pp.133-140
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• 2012

The study of Arundinaria munsuensis Y. Lee to this day was limited to the field of morphological species classification since its first discovery at Jiri mountain in the late 1990s. This native plants, one of Korean endemic species found in Jiri Mt. necessitates further studies about its use as revegetation plants or groundcover plants in urban areas. This study was launched from this need followed by summaries of results below related to its usage. This targeted species is a native Korean species which its natural distribution on the subalpine zone has merit for the wide range of climatic adaptation. Also, the coverage rate reached 78.3% in three years mostly by rhizome growth with an expectation of full coverage in four years providing less maintenance needs after planting. The net price for the construction of pot seedling methods of this plants is relatively economical than other normal revegetation construction methods. For these reasons, drilling for the plants on cut and fill soil slopes driven from pot seedling adapts Arundinaria munsuensis Y. Lee as efficient revegetation plant. Total construction cost for pot seedling work($30cm{\times}30cm$) of Arundinaria munsuensis was approximately 21,000won which is in reasonable price range when compared to other revegetation construction methods of disturbed slopes. As a native Korean plant, Arundinaria munsuensis has wide range of climatic adaptation with less maintenance requirement after planting. This study may suggest a strong possibility of Arundinaria munsuensis as a pot planting material in sloped area.

• 한국안전학회지
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• 제11권1호
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• pp.16-26
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• 1996

A.Satyanarayana와 다른이들은 [1.2.5]에서 domination이론을 사용하여 네트워크의 정확한 신뢰도 계산을 위한 새로운 topologic formel을 발견하였다. 이들은 이식을 통하여 그래프 G로 표현되는 어떤 시스템이나 네트워크의 신뢰도 계산을 위하여 path 또는 k-tree를 사용한 Inclusion-Exclusion식에 나타나는 항들(=2$^{m}$ -1, m은 path나 k-tree의 수)중 서로 소거되지 않는 항들은 그래프 G의 acyclic k-부분그래프(subgraph)와 1대 1로 상응되며, cyclic-과 k-부분그래프들에 상응되는 항들은 소거되어지거나 Inclusion-Exclusion식에 나타나지 않는 -결국 신뢰도계산에 필요없는- 항들임을 밝혔다. 이들은 이성질을 이용하여 그래프 G의 정확한 신뢰도계산을 위한 빠른 알고리즘을 제시하였다. 이 알고리즘은 결국 그래프 G의 path나 k-tree를 기초로 하는 Inclusion-Exclusion식에서 나타나는 항들중 소거되지 않는 항들에 1:1로 대응하는 acyclic k-subgraph만을 찾아 신뢰도계산을 할수있게 하여 준다. 이때 acyclic k-subgraph들은 각각의 domination을 갖으며, 이들은 Inclusion-Exclusion식에서 대응되는 항의 부호들의 합과 같다. 본 논문에서는 첫째로 신뢰도계산을 위하여 주어진 어떤 그래프 G에서 G를 구성하는 선(edge)을 기초로 하는 어떤 임의로 주어진 family M(G) (예: cutset이나 path, 또는 k-tree 등의 family)에 의한 (부분)그래프의 domination에 대한 성질을 관찰하고 몇가지 식을 유도한후, k-tree의 family K(G)를 기초로 한 어떤 그래프의 domination과 Inclusion-Exclusion식과의 관계를 고찰하고, 이식의 강력함과 응용의 가능성을 A. Satyanarayana의 topologic formel의 재증명을 통하여 보인다.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4149-4155
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• 2013

더 빠른 절삭속도와 이송속도를 위한 고속가공은 표면품위와 재료제거율의 증가를 초래한다. 이 논문은 고속가공을 위한 정면밀링커터를 사용한 가공에서 획득된 진동특성에 관한 절삭조건의 영향을 연구하였다. 이 논문에서, 직교배열 테이블에 기초한 다구찌 실험계획법은 고속 정면밀링커터를 사용한 진동특성을 연구하기 위해 적용되었다. 실험조건은 직교배열 $L_{27}(3^{13})$ 을 사용하였다. 실험의 계획과 분석은 S/N비(신호 대 잡음비)와 분산분석을 이용하여 진동에 관한 절삭조건의 영향을 연구하기 위해 수행되었다. 절삭 파라미터 즉 이송속도, 챔퍼길이, 절삭속도 그리고 절삭깊이는 진동 특성치를 고려하여 최적화 되었다.

• 토지주택연구
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• 제2권4호
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• pp.553-558
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• 2011

말뚝두부와 기초판의 연결방법으로서 기존의 강선남김방식은 시공성이 좋지 않고, 말뚝두부에 파손 및 균열이 발생할 가능성이 높을 뿐만 아니라 현장 인명사고가 자주 발생하여 최근에는 대안적인 방법으로서 원커팅에 의한 철근보강 방식이 제안되어 사용되고 있다. 하지만 이러한 방법들은 역학적인 성능규명에 의하여 그 상세가 구체적으로 제안 또는 검증된 사례가 없다. 이 연구는 원커팅 철근보강 방식에 있어서 최적 보강상세를 제안 할 목적으로 후 타설된 말뚝 내 속채움 콘크리트와 말뚝간의 전단마찰 저항력의 부족으로 인한 파괴를 실험을 통하여 규명하고, 적정 채움 깊이를 제안하였다. 실험결과에 근거하여 말뚝 부착파괴 강도를 안전측의 값으로 0.4MPa를 가정한다면, 부착파괴 이전에 철근이 항복에 도달하도록 하기 위해서 속채움 콘크리트의 깊이는 최소한 PHC 450과 PHC 500의 경우 600mm 이상, PHC 600의 경우 1,000mm 이상 확보하여야 할 것으로 판단된다.

• 한국유통학회지:유통연구
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• 제1권1호
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• pp.41-63
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• 1996

In spite of economy has a critical cycle such as, production, distribution and consumption, we hardly concentrated our study to distributional system and behavior. Especially in Korea, Traditional idea had tried to ignore the people who work in this economic value at all. Manufacturers, other than retailers and wholesalers, had a belief that the manufacturing can control distributional channels forever. Unfortunately, technological and educational advances caused the quality equalization among developing and developed countries as well as among big and small manufacturers in their products. By this reason, economists are searching the economists dark continet' mentioned by Peter Drucker as a new source of wealth. According to a report by well-known economic research institute in Switzerland, Korea has classified in the lower level group in terms of international compatitive power. At the same time, business firms complain that they are suffering from lack of SOC and infrastructures. As an important mean to overcome the economic bottleneck, economists suggest in improve our distributional atmosphere. Basically, distributional study has two sub-fields as: commercial and physical distributions, Distributional system mainly concerns about to shorten the distances of time and space between production and consumption. The closer the distances, the higher efficiency can be achieved. Building distributional system will cost, but tile results will save social costs. Based on this idea, economists proposed several ways to cut the distances and to save costs, Naturally, they hope their beliefs can be adapted by business firms and governments. But frequently, their theories doesn't make any fruit. This paper has studied about the composition of joint transportational and distributional systems. And, even though there's no Marshall in tile real world at this point authors are trying to define the transportational and physical distributional costs, the most powerful factor that can impact to economic decision making.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.293-300
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• 2008

Efficient designing of SRM Grains in the field of Rocketry is still the main test for most of the nations of world for scientific studies, commercial and military applications. There is a strong need to enhance thrust, improve the effectiveness of SRM and reduce mass of motor and burning time so as to allow the general design to increase the weight of payload/on board electronics. Moreover burning time can be increased while keeping the weight of the propellant and thrust in desired range, so as to give the time to control / general design group in active phase for incorporating delayed cut off if required. A mathematical design, optimization & analysis technique for Slotted Tube Grain has been discussed in this paper. In order to avoid the uncertainties that whether the Slotted Tube grain configuration being designed is best suited for achieving the set design goals and optimal of all the available designs or not, an efficient technique for designing SRM Grain and then getting optimal solution is must. The research work proposed herein addresses and emphasizes a design methodology to design and optimize Slotted Tube Grain considering particular test cases for which the design objectives and constraints have been given. In depth study of the optimized solution have been conducted thereby affects of all the independent parametric design variables on optimal solution & design objectives have been examined and analyzed in detail. In doing so, the design objectives and constraints have been set, geometric parameters of slotted tube grain have been identified, performance prediction parameters have been calculated, thereafter preliminary designs completed and finally optimal design reached. A Software has been developed in MATLAB for designing and optimization of Slotted Tube grains.