• 한국건설관리학회논문집
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• 제19권5호
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• pp.43-52
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• 2018

일반적으로 공사비에 대한 연구는 직접비 위주로 행해졌으며, 간접비를 면밀하게 산정하는 모델에 대한 연구가 부족하다. 본 연구의 목적은 국내 건설시장에서 큰 축을 차지하는 아파트 건설공사 현장의 현장관리비를 예측하기 위한 모델을 제시하는 것이다. 아파트 건설공사 현장 다수의 전체공사기간 동안의 실비사용 데이터를 분석하여 곡선접합 분석을 통해 공정률별 1일당 현장관리비를 도출할 수 있는 9차방정식을 제안하였으며, 이를 활용하여 300억 규모의 공사의 경우의 현장관리비를 추정하는 결과를 보여줌으로서 활용가능성을 설명하고 있다. 선행연구에서는 총 현장관리비의 규모의 변화패턴을 직접적으로 확인할 수 있는 다항식을 도출한 사례는 없었던 점에 비추어 본다면, 본 연구에서 제시한 모델은 그 편의성과 면밀성에 합리적 근거를 토대로 현장관리비를 예측할 수 있다는 점에서 연구의 기여도가 있다.

• Structural Engineering and Mechanics
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• 제8권2호
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• pp.165-180
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• 1999

The cost effectiveness of using steel roof systems for residential buildings is becoming increasingly apparent with the decrease in manufacturing cost of steel components, reliability and efficiency in construction practices, and the economic and environmental concerns. While steel has been one of the primary materials for structural systems, it is only recently that its use for residential buildings is being explored. A comprehensive system for the design of residential steel roof truss systems is presented. In the first stage of the research the design curves obtained from the AISI-LRFD code for the manufactured cross-sections were verified experimentally. Components of the truss systems were tested in order to determine their member properties when subjected to axial force and bending moments. In addition, the experiments were simulated using finite element analysis to provide an additional source of verification. The second stage of the research involved the development of an integrated design approach that would automatically design a lowest cost roof truss given minimal input. A modified genetic algorithm was used to handle sizing, shape and topology variables in the design problem. The developed methodology was implemented in a software system for the purpose of designing the lowest cost truss that would meet the AISI code provisions and construction requirements given the input parameters. The third stage of the research involved full-scale testing of a typical residential steel roof designed using the developed software system. The full scale testing established the factor of safety while validating the analysis and design procedures. Evaluation of the test results indicates that designs using the present approach provide a structure with enough reserve strength to perform as predicted and are very economical.

• 패션비즈니스
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• 제25권4호
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• pp.36-60
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• 2021

This study aimed to provide basic data for establishing a sizing system for menswear by investigating body size changes and body shapes in adult men in their 30s to 50s. Data on 52 different upper body categories collected from 4,314 people during the 5-7th Size Korea surveys were analyzed. The waist height, hip height, torso and arm lengths, and torso and upper limb circumferences increased while the arm joint sizes decreased. According to factor analysis, factors 1 and 2 referred to 'the horizontal size of the upper body and limbs' and the 'torso height and upper limb length', respectively, while factors 3 and 4 represented 'shoulder size' and 'upper body length' respectively. In clustering analysis, types 1 and 2 were 'short and fat' and 'tall and thin,' respectively, while types 3 and 4 represented 'tallest and chubby' and 'shortest and small' respectively. Torso length increased in the 30 to 40s in type 1 while torso circumference increased in the 30s and late 40s in type 2. In type 3, shoulders got bigger in the 30s. In type 4, torso circumference increased in the early 30s, and torso length increased in the late 40s. 'Thin' was a typical body shape in the early 30s. Among early 40s men, distribution evolved from 'small' to 'thin.' In the late 40s, while the percentage of 'small' decreased, the ratio of 'obese' increased. In the 50s, 'small' was the most common.

• 한국수소및신에너지학회논문집
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• 제32권4호
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• pp.245-255
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• 2021

Various studies about metallic bipolar plates have been conducted to improve fuel cell performance through flow field design optimization. These research works have been mainly focused on fuel cells for vehicle, but not fuel cells for building. In order to reduce the price and volume of fuel cell stacks for building, it is necessary to apply a metallic flow field, In this study, for a metallic flow field applied to a fuel cell for building, the effect of a change in the flow field shape on the performance of a polymer electrolyte membrane fuel cell was confirmed using a model and experiments with a down-sizing single cell. As a result, the flow field using a metal foam outperforms the channel type flow field because it has higher internal differential pressure and higher reactants velocity in gas diffusion layer, resulting in higher water removal and higher oxygen concentration in the catalyst layer than the channel type flow field. This study is expected to contribute to providing basic data for selecting the optimal flow field for the full stack of polymer electrolyte membrane fuel cells for buildings.

• 한국의류산업학회지
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• 제21권3호
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• pp.318-325
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• 2019

This study analyzes current self-nail tips and nail-tip satisfaction. The study method selected from 3 domestic and 3 overseas companies analyzed current self-nail tips based on brand recognition and sales rate. A questionnaire was conducted on 261 adult women in their 20s and 50s about the satisfaction of nail care and self-nail tips. The results are as follows. As a result to analyze the current nail tips, there were products that did not contain the type of nail tip or the composition and ingredients of the glue. An online survey of the sizes of the current nail tips indicated differences in the sizing system method and that the presented sizes are different. The response rate was the highest for the survey results on why self-nail tips were preferred for respondents who prefer self-nail tips because the price was cheap. The reason why they did not prefer self-nail tips was that the degree of completeness was lower and the fitness was not good. In addition, it showed a high response rate in that the adhesive strength was poor and the size did not fit the nails. Therefore, it is necessary to develop a size for nail types by ergonomic design and develop a self-nail tip that can reduce nail damage.

• 자원리싸이클링
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• 제28권2호
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• pp.31-39
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• 2019

인쇄회로기판(PCB) 제조 공정 중 발생된 슬러지로부터 구리성분을 건식제련방법으로 회수하기 위해서 슬러지를 원료로 한 펠렛화 연구를 진행하였다. 슬러지 펠렛화를 위해 건조, 해쇄, 입도분급의 전처리 실시하였고, 혼합 및 압축장치를 포함한 펠렛화 기기를 개발하였다. 제조된 펠렛의 물리적 특성평가는, 슬러지 입도, 펠렛화 압축 횟수를 변화시키면서 비파괴 낙하횟수, 압축강도를 측정하였다. #140 mesh over의 입자를 제거한 경우, 펠렛의 특성은 0.6 MPa, 9.3회로 향상되었으며, 여기에 #325 under 입자를 한번 더 제거한 경우 0.82 MPa, 19.0회로 더욱 더 향상되었다. 이는 조립자의 경우, 충진밀도를 감소시키고, 미립자의 경우 성형에 요구되는 점결제의 투입량을 증가시키기 때문에 나타난 결과로 판단된다.

• 융합정보논문지
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• 제9권2호
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• pp.85-93
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• 2019

현재 승강기의 크기에 관한 공인된 표준이 존재하지 않는다. 각 승강기 제조 회사들은 EN-CODE와 국내검사기준에서 정의하는 용량대비 최대사용 카 바닥 면적을 이용하여 승강기의 용량 산출 기준에 맞는 최대 허용 바닥 면적을 설정하고 자신들의 기준으로 승강기 크기를 결정하고 있다. 본 논문에서는 승강기 크기를 보다 쉽게 결정 할 수 있는 방법을 제시한다. 이를 위해 승강로의 치수를 입력하면 승강기의 크기를 계산해주는 프로그램을 구현하였다. 이 프로그램은 건물의 이미 결정된 승강로 크기에 따라 승강기 요소들을 고려하여 현재 사용 중인 EN-CODE와 국내검사기준에 맞는 승강기의 크기를 계산해 주어 빠른 의사결정과 승강기 설치에 있어서 유용한 도구가 될 것이라 사료된다.

• 국제초고층학회논문집
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• 제8권2호
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• pp.101-106
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• 2019

Assessing the energy performance of supertall buildings often does not consider variations in energy consumption due to the change of environmental conditions such as temperature, pressure, and wind speed associated with differing elevations. Some modelers account for these changing conditions by using a conventional temperature lapse rate, but not many studies confirm to the appropriateness of applying it to tall buildings. This paper presents and discusses simulated annual energy consumption results from a 600 m tall skyscraper floor plate located in Dubai, UAE, assessed using ground level weather data, a conventional temperature lapse rate of $6.5^{\circ}C/km$, and more accurate simulated 600 m weather data. A typical office floorplate, with ASHRAE 90.1-2010 standards and systems applied, was evaluated using the EnergyPlus engine through the OpenStudio graphical user interface. The results presented in this paper indicate that by using ground level weather data, energy consumption at the top of the building can be overestimated by upwards of 4%. Furthermore, by only using a lapse rate, heating energy is overestimated by up to 96% due to local weather phenomenon such as temperature inversion, which can only be conveyed using simulated weather data. In addition, sizing and energy consumption of fans, which are dependent both on wind and atmospheric pressure, are not accurately captured using a temperature lapse rate. These results show that that it is important, with the ever increasing construction of supertall buildings, to be able to account for variations in climatic conditions along the height of the building. Adequately modeling these conditions using simulated weather data will help designers and engineers correctly size mechanical systems, potentially decreasing overall building energy consumption, and ensuring that these systems are able to provide the necessary indoor conditions to maintain occupant comfort levels.

• 한국산업융합학회 논문집
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• 제24권1호
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• pp.31-43
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• 2021

In this study, approximate design optimization using various meta-models was performed for the structural design of active type deck support frame. The active type deck support frame was newly developed to facilitate both transportation and installation of 20,000 ton class offshore plant topside. Structural analysis was carried out using the finite element method to evaluate the strength performance of the active type deck support frame in its initial design stage. In the structural analysis, the strength performances were evaluated for various design load conditions that were regulated in ship classification organization. The approximate optimum design problem based on meta-model was formulated such that thickness sizing variables of main structure members were determined by achieving the minimum weight of the active type deck support frame subject to the strength performance constraints. The meta-models used in the approximate design optimization were response surface method, Kriging model, and Chebyshev orthogonal polynomials. The results from approximate design optimization were compared to actual non-approximate design optimization. The Chebyshev orthogonal polynomials among the meta-models used in the approximate design optimization represented the most pertinent optimum design results for the structure design of the active type deck support frame.

• 한국의류산업학회지
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• 제23권6호
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• pp.810-825
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• 2021

This study measured and analyzed clothing pressure at each measurement part of commercial body shapers to provide basic information for product design and clothing pressure standard and level. This study used five body shaper. Clothing pressure measurements were taken at 18points: Anterior area 8points, lateral area 5points, posterior area 5points. The findings of this study were as follows. As a result of measuring the clothing pressure, the body shaper 1 showed the highest pressure, and body shaper 5 showed the lowest pressure at almost of the measurement points of the three body types. In some cases, body shapers 2, 3, and 4 showed different orders of pressure depending on the measurement point. The highest measured values in most body shapers were the P1 shoulder area and the P2 bust area. The lowest measurement area differed by body type, but mainly P3 underbust area, P4 thorax area and P9 axillary area, P11 waist lateral area, P13 hip lateral area. These body shapers showed different results depending on the the manufacturers and body type of middle-aged women, and because there was no standard for the pressure value. Therefore, it is necessary to design a body shaper sizing system after accurately setting the clothing pressure value for each body part of the consumer.