• 상하수도학회지
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• 제19권6호
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• pp.749-757
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• 2005

The present study analyzed actual cases of designed flow estimation method and designed flow rate of sewage pipe lines. In order to examine the effects of peak-hour demand factor estimation with given daily highest peak loading, we analyzed its effects on designed flow rate with changing the peak-hour demand factor from 2.0 to 10.0. The results of this study are as follows. When reviewing the recent designs, we found that 59.4% of pipe line with 250mm and 300mm diameter, which fall under minimum allowable pipeline did not meet the minimum velocity which is specified as 0.6m/sec in design standards. The pipe line that have minimal access population or have very low slope did not satisfy the minimum velocity. In estimating the designed sewage flow, the applied daily highest peak loading and hourly highest peaking loading were the load factor for the entire population of the planned area, and for the peak loading of the initial pipes connected to a very small population, we applied the same factor as that applied to the entire area and, as a result, the hourly highest flow was underestimated. Because, in case of the initial pipes, the method of applying the same peak loading to all subject areas is highly possible to produce underestimated design flow, when estimating the designed flow of the initial pipes connected to a small population need to adopt a rational flow factor according to the size of population. For this, it is considered to investigate and analyze raw data on daily and hourly variation of sewage flow.

• 패션비즈니스
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• 제26권1호
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• pp.30-40
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• 2022

This study aims to provide basic information on the changes in lower body measurements and shapes of women in their 20s for developing better fitting slacks patterns and a more applicable sizing system that can be widely utilized for women of all ages. Factor and cluster analysis were performed on 1,360 women's direct measurement data within the age group from the 5^th (2004) and 7^th (2015) Korean Human Body Measurement Investigation. The factor analysis identified four factors and explained 82.54% of the total variance; Factor 1, horizontal measurements of lower body; Factor 2, vertical lengths of lower body; Factor 3, measurements of leg and hip areas; Factor 4, lengths of hip and crotch areas. The cluster analysis categorized the lower body shapes of each age group into four shapes; Shape 1, a petite lower body with short legs; Shape 2, a long lower body with medium built; Shape 3, an obese abdomen and legs; Shape 4, a short and slim lower body. Shape 4 (36.5%), Shape 2 (31.2%), Shape 1 (27.8%), and Shape 3 (4.5%) were placed in the order of frequency from the highest to lowest among all the age groups. The findings of this study showed gradual changes in the lower body measurements and shapes of women in their 20s and relevant physical features of each age group. They can be utilized for developing women's slacks patterns with better fitting and more comfort.

• 대한토목학회논문집
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• 제28권2D호
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• pp.155-162
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• 2008

본 연구에서는 전체 시간대별 교통량을 관측하지 못하여 설계시간교통량을 구할 수 없는 지점에 대하여 설계시간계수를 추정하는 방법에 대하여 분석하였다. 수시조사는 연 1~5회 조사되며, 이러한 지점에서는 설계시간교통량을 구할 수 없어 설계시간계수를 구할 수 없다. 분석을 위하여 2006년 일반국도 상시조사 지점의 시간대별 교통량을 이용하여 분석하였다. 설계시간계수를 추정하기 위하여 시간대별 교통량의 변동을 반영하는 시간대별 교통량의 변동계수(Coefficient of Variance), 시간대별 교통량의 표준편차, 첨두시간교통량(peak hour volume)과 도로의 특성을 파악할 수 있는 중차량비율, 주야율, AADT와 중방향계수 등의 변수를 독립변수로 하여 각 변수들과 설계시간계수와의 상관분석 및 회귀분석을 이용하여 설계시간교통량을 추정하였다. 산점도를 통하여 독립변수와 종속변수의 관계를 분석한 결과 대부분의 변수들이 곡선의 형태를 띠는 것으로 나타나 선형회귀분석보다 곡선회귀분석이 더 적합한 것으로 나타났다. 곡선회귀분석으로 분석한 결과 AADT를 독립변수로 하여 분석한 대수모형이 결정계수가 가장 높은 것으로 나타났다.

• 전기의세계
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• 제14권4호
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• pp.8-17
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• 1965

Firstly, this study has analyzed the following factors affecting the optimum specifications and design of distributive transformers: 1. Facilities installation cost per unit power output. 2. Facilities operating & maintenance cost per unit power output. 3. Production cost per unit power output. 4. Load factor. 5. Loss factor. Secondly, it has clarified the relations between the following factors and the specifications and design of distributive transformers; 1. No-load loss., 2. Load loss., 3. Voltage regulation., 4. Exciting current. Finally, it has determined the method of the most economic design for the transformers using the above factors and relations, and, for optimum the illustrative purpose, suggested their optimum specifications, way of evaluation, and merits by means of typical example.

• 디자인학연구
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• 제16권3호
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• pp.81-90
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• 2003

본 연구의 목적은 인간의 본질인 신체적ㆍ정신적 특성에 따른 제품의 새로운 분류 방식을 제시하고 이를 통해 제품의 미래를 이해하는데 있다. 연구의 목적을 위해 인간과 제품의 관계 특성을 과거와 미래를 통해 비교 분석하였고, 이 과정에서 제품을 발생학적으로 분류할 수 있었다. 연구는 그 결과를 '신체적 제품'의 미래와 '정신적 제품'의 미래로 나타냈다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권6호
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• pp.263-272
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• 2001

The paper presents the design of a segmented type synchronous reluctance motor(SynRM) to increase its torque and power factor. The main feature of a segmented type synchronous reluctance motor is the flux barrier. Thus, the design process to find optimum value of various geometric parameters including flux barrier will be explained. Optimum value of each parameter is found where the d, q inductance difference and saliency ratio are maximized because these inductance characteristics are related to torque and power factor. Finite Element Analysis will be used to simulate motor characteristics. Analysis results of redesigned SynRM show higher saliency ratio over 10 and improved value of maximum power factor.

• 설비공학논문집
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• 제25권12호
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• pp.654-659
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• 2013

This paper presents a numerical optimization of louvered fins to enhance the JF factor in terms of the design parameters, including the fin pitch, the number of louvers, the louver angle, the fin thickness, and the re-direction louver length. We carried out a parametric study to select the three most important parameters affecting the JF factor, which were the fin pitch, number of louvers, and the louver angle. We optimally designed the louvered fin by using 3rd-order full factorial design, the kriging method, and a micro genetic algorithm. Consequently, the JF factor of the optimum model increased by 16% compared to that of the base model. Moreover, the optimum model reduced the pressure drop by 17% with a comparable heat transfer rate.

• Journal of the Korean Data and Information Science Society
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• 제19권4호
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• pp.1059-1071
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• 2008

In a balanced factorial design with a nested factor where crossed factors as well as a nested factor exist simultaneously, powers of the rank transformed FR statistic for testing the main, nested and interaction effects are superior to those of the parametric F statistic. In heavy tailed distributions such as exponential and double exponential distributions, powers of the FR statistic show much higher level than those of the F statistic. Further powers of the F and FR statistic for testing the main effect show the highest level in an absolute size as compared with powers of the F and FR statistic for testing the nested and interaction effects. However powers of the FR statistic for testing the nested and interaction effects rather than the main effect are greater in a relative size than powers of F statistic for the all population distributions.

• International Journal of Fluid Machinery and Systems
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• 제3권4호
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• pp.369-378
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• 2010

The creation of the hydraulic turbine flow factor map will undoubtedly benefit its design by decreasing both the design cycle time and product cost. In this paper, the geometry and flow variables, which effectively affect the flow factor, are proposed, analyzed and determined. These flow variables are further used to create the operating condition maps by using different model approaches categorized into Response Surface Method (RSM) and Artificial Neural Network (ANN). The accuracies of models created by different approaches are compared and the performances of model approaches are analyzed. The influences of chosen variables and the combination of Principle Component Analysis (PCA) and model approaches are also studied. The comparison results between predicted and actual flow factors suggest that two-hidden-layer Feed-forward Neural Network (FFNN), and one.hidden-layer FFNN with PCA has the best performance on forming this mapping, and are accurate sufficiently for hydraulic turbine design.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.902-904
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• 1996

In this paper, we proposed the reasonable design standard and countermeasures of Demand Factor for large office buildings, that was made by the statistical way considering actual conditions, such as investicated electric equipment capacity, electric power consumption, etc. So as to save electric equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electric rates, we can be contributed by the application of the design standard. The result of saving effect is showed to confirm the practical use of the proposed Demand Factor, and also, it is believed that this proposed Demand Factor will be useful in electric equipment operation and planning.