• Journal of Korean Society of Water and Wastewater
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• v.19 no.6
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• pp.819-826
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• 2005

To guarantee the disinfection ability in clearwell, a value of CT is considered where C[mg/l] is disinfectant residual at the exit of clearwell and T[min] means $T_{10}$, the contact time when 10% of tracer is out of clearwell after introducing the tracer at the inlet. To meet a CT value required, increasing the C value is not recommended because high C value can increase potential of producing disinfection by product like THMs. Increasing the hydraulic efficiency surrogated by $T_{10}$ is thus an option widely recommended. Right now, it is widely adopted estimating $T_{10}$ considering LW ratio only due to the suggestions of previous researches. The authors think however there are other factors to consider including shape, flow rate, configuration of inlet and outlet, and the existence of intra basin. This study is initiated to closely look at the effects of two factor on hydraulic efficiency. The factors are shape and inlet flow velocity, i.e., inflow. For that, computational fluid dynamics (CFD) model is developed and pilot test is also carried out. The results show that at a L/W ratio, disinfection ability is overestimated with larger length in shape and higher inlet flow velocity. This suggests that in determining $T_{10}$, the shapes of clearwell and inlet flow velocity should also be considered as well as L/W ratio.

• Fashion & Textile Research Journal
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• v.22 no.4
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• pp.495-503
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• 2020

This study classified lower body shape according to thigh and waist shape to improve the fit of skinny blue jeans in adult women in their 20s. We analyzed the three-dimensional automatic measurement data, three-dimensional indirect measurement data, and index data using the three-dimensional female (20-29 years old) body scan data provided by Size Korea (6^th Korean Human Dimensional Survey Project). Factor analysis was performed to classify body type. We selected and analyzed 34 items related to thigh shape based on index items, angle items, and protrusion amount items from 99 items; consequently, seven factors were extracted and 82.39% of the total variance was explained. Cluster analysis according to factor analysis classified it into 4 types, and a post-test Duncan test was conducted to classify thigh features according to classified types. As a result, the characteristics of lower body shape according to the thigh types of women in their 20s are as follows. Lower Body Type 1 is shape with a more prominent belly and less prominent thighs. Lower Body Type 2 is a slender body figure with larger hips. Lower Body Type 3 has more prominent thighs compared to the waist and belly. Lower Body Type 4 has both a prominent belly and prominent thighs.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.73-83
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• 2016

Bearing stress near anchor plates is usually very high due to prestressing force in anchorage zone of concrete structure used post-tensioned prestressed method. In order to effective utilization of cross section and crack control, appropriate size of anchorage plates should be used to prevent crack initiation and failure of concrete structures eventually. This study aims to suggest equation for effective area of bearing plate of rectangle type and circular type by Highway Bridge Design Specification and PTI etc. A shape factor according to bearing plate shape is suggested based on numerical analysis, and it can be used suitability for design of special anchorage plate dimension.

• The KSFM Journal of Fluid Machinery
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• v.10 no.2 s.41
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• pp.7-15
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• 2007

A numerical procedure for optimizing the shape of three-dimensional channel with V-shaped ribs extruded on both walls has been carried out to enhance the turbulent heat transfer. The response surface based optimization is used as an optimization technique with Reynolds-averaged Wavier-stoked analysis. Shear stress transport (SST) turbulence model is used as a turbulence closure. Computational results for average heat transfer rate show good agreements with experimental data. The objective function is defined as a linear combination of heat transfer and friction loss-related terms with a weighting factor. Three dimensionless variables such as, rib pitch-to-rib height ratio, rib height-to-channel height ratio, and the attack angle of the rib are chosen as design variables. Nineteen training points obtained by D-optimal designs for three design variables construct a reliable response surface. In the sensitivity analysis, it is found that the objective function is most sensitive to the ratio of rib height-to-channel height ratio. And, optimal values of design variables have been obtained in a range of the weighting factor.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.8
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• pp.663-671
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• 2007

In this work, shape optimization of a wire-wrapped fuel assembly in a liquid metal reactor has been carried out by combining a three-dimensional Reynolds-averaged Navier-Stokes analysis with the radial basis neural network method, a well known surrogate modeling technique for optimization. Sequential Quadratic Programming is used to search the optimal point from the constructed surrogate. Two geometric design variables are selected for the optimization and design space is sampled using Latin Hypercube Sampling. The optimization problem has been defined as a maximization of the objective function, which is as a linear combination of heat transfer and friction loss related terms with a weighing factor. The objective function value is more sensitive to the ratio of the wire spacer diameter to the fuel rod diameter than to the ratio of the wire wrap pitch to the fuel rod diameter. The optimal values of the design variables are obtained by varying the weighting factor.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.9
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• pp.1051-1057
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• 2004

A numerical optimization procedure for the shape of three-dimensional channel with angled ribs mounted on one of the walls to enhance turbulent heat transfer is presented. The response surface method is used as an optimization technique with Reynolds-averaged Wavier-Stokes analyses of flow and heat transfer. SST turbulence model is used as a turbulence closure. Computational results for local heat transfer rate show reasonable agreements with experimental data. The pitch-to-height ratio of the rib and rib height-to-channel height ratio are set to be 9.0 and 0.1, respectively, and width-to-rib height ratio and attack angle of the rib are chosen as design variables. The objective function is defined as a linear combination of heat-transfer and friction-loss related terms with weighting factor. Full-factorial experimental design method is used to determine the data points. Optimum shapes of the channel have been obtained in the range from 0.0 to 0.1 of weighting factor.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.453-461
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• 1999

The estimation of fatigue life at the design stage is very important in order to arrive at feasible and cost effective solutions considering the total lifetime of the structure and machinery compo-nents. In this study the practical procedure of prediction of fatigue life by use of cumulative damage factors based on Miner-Palmgren hypothesis and probability density function is shown with a $135,000m^3$ LNG tank being used as an example. In particular the parameters of Weibull distribution taht determine the stress spectrum are dis-cussed. At the end some of uncertainties associated with fatigue life prediction are discussed. The main results obtained from this study are as follows: 1. The practical procedure of prediction of fatigue life by use of cumulative damage factors expressed in combination of probability density function and S-N data is proposed. 2. The calculated fatigue life is influenced by the shape parameter and stress block. The conser-vative fatigue design can be achieved when using higher value of shape parameter and the stress blocks divded into more stress blocks.

• The Research Journal of the Costume Culture
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• v.28 no.5
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• pp.639-651
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• 2020

This study utilized data to classify and characterize the body types of plus-size adult men aged in their 30s and 40s. Diversity is an important factor in the era of inclusive design, and discussion about size diversity to include the plus size should be accommodated. Data from 493 adult men classified as obese (with a World Health Organization criterion ≥25 BMI) were used for the analysis. The results of the study are as follows. Six independent factors were extracted using factor analysis for cluster analysis, which were then classified into five types. Type 1 (29.01%) was identified as body type I with the smallest degree of obesity. Type 2 (15.4%) was identified as body type Y with wide shoulders and a thin waist. Type 3 (14.2%) was the largest body volume (body type O), while the fourth (19.27%) identified as body type H has a large height and upper body. Lastly, type 5 (22.11%) has a long lower body and a slim abdomen, referred to as body type X. This study presents a basis for the development of various clothing sizes utilizing the body shape characteristics of plus-size men in their 30s and 40s. Follow-up research is needed to develop patterns for plus size men and to design various products.

• Korean Institute of Interior Design Journal
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• no.30
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• pp.68-77
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• 2002

From ancient to modern architecture, the light in the architecture spaces as the only changing factor, was the most important theme contributing vitality to the space and judging its character and expression. The efforts, to acquire both natural-physical light and internally experienced spiritual-supernatural light, had been revealed in several ways of the architecture from the ancient architecture. It was the main issues on the christian architecture. In this study, 1 have intended to determine how the light, the most important factor on the christian architecture symbolizing the blessing of God and forming the pious and restrained spaces has been expressed in the church spaces. For this purpose, I have compared and analysised the examples of the using the light, to the arts of the modern maestros of architecture and newly constructed churches in Korea on the way of light input pattern by the shape of windows. The results from the examples show that the most outstanding point of the modern christian architecture compare to the past, is that the natures of the inputted light has many diversities by the architects. And I reached the fact that the constructers by their own will to acquire the intended light, they are chose progressive light expressing methods through the shape of windows.

• Journal of Sasang Constitutional Medicine
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• v.25 no.3
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• pp.145-157
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• 2013

Objectives This study was aimed to reveal the characteristics of the body shape, face, voice and temperament in Taeyangin. Methods The subjects were recruited from November 2005 to August 2012. Sasang constitutional specialist in each clinics confirmed the Sasang Constitution. Taeyangin (TY) became a standard guidance to be compared with each other Sasang type. Anova test was used in analyzing continuous variables and factor analysis was conducted in temperament questionnaire in advance. Generalized propensity score with age and body mass index (BMI) was used in adjusted model. Significant level was .05 Results 1. The TY body shape were generally smaller than Taeeumin (TE) (p<0.001) and Soyangin (SY) (p<0.05) in crude. The TY body shape were still smaller than TE (p<0.05) and there was no significant difference between TY and SY except rib circumference in males and forehead circumference (p<0.05) in females in adjusted model. 2. The size of face and nose in TY was smaller than in TE and there was different between males and females' TY and others in the characteristics of eye, nose and forehead variables in crude (p<0.05). Most of differences between TY and TE were disappeared in adjusted model. 3. The vocal height and speed of TY was different other types and there was different between males and females' TY in some of frequency change rate in crude (p<0.05). Most of differences between TY and other types were similar before and after adjusted model. 4. The temperament of TY was different with SE before and after adjusted mode 1 (p<0.05). TY males showed difference in expression factor and TY females showed difference in behavior factor compared with TE respectively (p<0.05). Conclusions This study reveals characteristics of body shape, face, voice and character in the TY males females compared with each other type respectively.