• 한국자동차공학회논문집
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• 제23권1호
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• pp.105-111
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• 2015

Since 2007, Insurance Institute of Highway Safety(IIHS) has conducted the new bumper test using bumper barrier to estimate the repair cost of impacted vehicle. In this study, for the front body FE model of a medium size passenger car analyzes were carried out to optimize the shape of backbeam center reinforcement bracket. First, overlap effect was examined with changing the overlap magnitude and spot welds were added along the backbeam center line for reducing the section shear deformation. Next, for an overlap model design parameter study was performed for the bracket. Thickness effect was examined and an inner reinforcement was added to the bracket. Also, the lower part of bracket was deleted and additionally the bracket length was extended. The results were discussed in terms of backbeam backward deflection, barrier backstop intrusion and weight. Compared with the current design, the final model showed 44.1% bracket weight reduction with 30.0% decrease of backbeam deflection.

• 복식문화연구
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• 제5권4호
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• pp.130-158
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• 1997

This study outputs calculation of regression of each items for production of torso basic pattern according to 6 body types as the result of another study and intends to present drawing method of torso model by short measure method modified and supplied and supplied by experiments of wearing clothing. SAS(Statistical Analysis System) is used for figures management and methods for analysis used are Frequency Analysis, Means Analysis, Regression Analysis, Correlation Analysis, etc. Results are as follows. 1. Correlation analysis is used to output the size necessary for torso prototype drawing by sort measure method and waist front length, back length, crotch length, shoulder point-cerricale-shoulder point, bust circumference, waist circumference, weight, etc, are set up as representative items calculation of regression of each type is suggested. 2. In the result of experiment of the first wearing clothing intended for 5 in each type and the whole 30, to develop torso prototype drawing method by short measure method, as we find some problems of the shape and propriety of neck root circumference line, the position of shoulder point, pulling or hold armpit parts, waist circumference line, the degree of dissatisfaction is high, so the second experiment of wearing clothing is propriety of each part is improved, all items except the length and quantity of shoulder dart, waist in back bodice, clearance quantity of hip circumference, and the place of shoulder line in side bodice. So, it was modifed and supplied and then the third torso prototyped drawing method by shout measure method was suggested. The third prototype drawing method was suggested, by modifying and supplying.

• International Journal of Automotive Technology
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• 제6권2호
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• pp.141-148
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• 2005

In order to reduce the time and costs of improving the performance of vehicle suspensions, the techniques for optimizing damping and air spring characteristic were proposed. A full vehicle model for a bus is constructed with a car body, front and rear suspension linkages, air springs, dampers, tires, and a steering system. An air spring and a damper are modeled with nonlinear characteristics using experimental data and a curve fitting technique. The objective function for ride quality is WRMS (Weighted RMS) of the power spectral density of the vertical acceleration at the driver's seat, middle seat and rear seat. The objective function for handling performance is the RMS (Root Mean Squares) of the roll angle, roll rate, yaw rate, and lateral acceleration at the center of gravity of a body during a lane change. The design variables are determined by damping coefficients, damping exponents and curve fitting parameters of air spring characteristic curves. The Taguchi method is used in order to investigate sensitivity of design variables. Since ride and handling performances are mutually conflicting characteristics, the validity of the developed optimum design procedure is demonstrated by comparing the trends of ride and handling performance indices with respect to the ratio of weighting factors. The global criterion method is proposed to obtain the solution of multi-objective optimization problem.

• 한국의류산업학회지
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• 제18권2호
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• pp.216-224
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• 2016

Recently, the interest in a garment that accentuates a fit and slender body continues to be highly desirable. Customers frequently want to wear a slim designed jacket that fits well, reflecting the trends of being young and slim. Accordingly, this research collected information on brands with ready-to-wear slim fit tailored jackets that target female customers in their 30s. By identifying the jacket pattern design and production state by brand, and evaluating the appearance when wearing the jacket, I was able to draw up the following conclusions. First, the fit highlights many problems because of the difference between the model size of brands that targeted domestic women in their 30s and the standard somatotype of them. This can be solved by considering the somatotype of women in their 30s when choosing the models. Second, the relative simplicity of the pattern should allow a slim fit tailored jacket to be produced that fits the front, back and side well. This would lead to the development of a jacket that would fit better as well as allowing for ease of movement. Similar to this, the model size of domestic brands changes frequently and customers prefer the size of a slim model instead of the size suitable for a target's somatotype. This results in a limit on the levels of satisfaction regarding brand targets for body types. Accordingly, it is hoped that this research will become the standard data for the development of a slim fit tailored jacket that will fit women in their 30s well.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.954-960
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• 2001

Axial fans are widely used in heavy machines due to their ability to produce high cooling of engines. At the same time. the noise generated by these fans causes or serious problems. This work is concerned with the low noise technique of discrete. The prediction model. which allowed the calculation of acoustic pressure at the frequency and it's harmonics, has been developed by Farrasat and the Helmholtz-Kir. The newly developed Helmholtz-Kirchhoff BEM for thin body is used to calculate the sound field of the fan that is located in a engine room. To calculate the unsteady resultant force over blade. Time-Marching Free-Wake Method are used. The fan noise of fan sys unsymmetric engine-room is predicted. In this paper. the discussion is confined to and discrete noise of axial fan and front Part of engine room in heavy equipments.

• 소음진동
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• 제9권1호
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• pp.97-102
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• 1999

Structure-borne noise is an important aspect to consider during the design and development of a vehicle. In this work. it was desired to identify the primary paths associated with structure-borne noise generated from the engine and front suspension. An experimental source-path-receiver model was used to characterize the system. A variety of primary sources such as engine. tires or exhaust system generate vibrations of the inner surfaces of the passenger compartment of a vehicle which subsequently radiate noise. The source was characterized by the force acting at the engine-to-body interface. and the path was characterized by pressure over force FRF's. The excitation forces were indirectly determined using dynamic stiffness of rubber mount or the system accelerance matrix. Through these analysis, path contribution diagram which is well expressed primary noise path is obtained.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.616-621
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• 2004

In this paper, the crush characteristics of a tilting train express (TTX) M-car design are evaluated with a head-on collision scenario. Its body shell is divided into three parts - front end, middle section, and rear end. For each part, crush-force relation is evaluated numerically through 3-dimensional shell element analysis with LS-DYNA. TTX's embody structure is a hybrid type structure made of steel and composite materials. Composite sandwich panels are modeled as layered shells whose layers have different material properties. And a damage material model is used to consider the effect of stiffness degradation during deformation. The crush characteristics obtained from these calculations will be used as material modeling data of full-rake collision analyses.

• 패션비즈니스
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• 제20권4호
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• pp.189-206
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• 2016

A breast model was for the human body was devised by studying a body scan and human body index of a desirable breast type. Thus, when manufacturing various 3D models, these results can accordingly become a fundamental basis for realizing a desirable breast model. This study aims to provide a basic data for designing the cup patterns of brassieres in order to improve the function and wearing comfort. The comfort of three kinds of brassieres were compared: one manufactured by the actual measured size; another manufactured as per the ratio of desirable upper and lower breast lengths; and the third manufactured by the 3D model attained by the desirable human body ratio. In this study, we suggest a process for realizing the desirable breast model using the ratio of bust breadth and waist front length, which are the components for deciding the appropriate position and size of breast, and which are easy to measure. The ideal breast shape is an equilateral triangle formed by connecting the nipple with the center of the clavicle. After deciding the interval between the nipples, this value can be used to configure the locations of nipples by drawing a tangent, with equal length, from the anterior neck point (which is the center of clavicle) to the nipple. Also, since inside points of breast do not exist, the outer point of breast, upper point of breast, and below point of breast on the same plane, and the depths from the nipple point to the respective points, are applied to simulate a 3D image, by modifications along the x, y, and z axes. Depending on the type of breast, the length from the center of shoulder to the nipple, the diameter of breast, upper length of breast, and the position of nipple, are different. In conical or protruding breast, the wearing sensation is better when the nipple point of brassiere was lifted, by modifying the upper and lower lengths of breast. Considering the wearing sensation and function of a brassiere, it was better to leave the wearer's size as it is and use a pad within the same cup, rather than increase the basal area of the breast in order to increase the volume.

• 패션비즈니스
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• 제8권4호
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• pp.22-32
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• 2004

The purpose of this research is to know the pattern of Hanbok Jegory with measuring Jegory and studying manufacturing method of the Jegory used currently. It is a purpose to find constitutional problem caused by the character of the bending somatotype and, to study the standard model of the Jegory for bending somatotyped women in old age, by comparison of this fitness for bending-somatotyped women in old age. The results obtained are as follows; 1. The kinds of measurements considered in manufacturing process are Hwajang Length, Bust girth, and the skirt length. The length of Jegory and width of Neck are also considered. 2. Manufacturers consider somatotype the most important thing when they make Jegory for women in old age. Front length, Back length and Width of the Jegory are considered secondly important. 3. The results of the comparison show that the Standard Hanbok drafting method is not suitable for drafting Jegory for bending somatotyped women in old age. 4. The suitability test for the model designed by the above methods shows that it fits in bending somatotyped women in old age better than standard drafting method. The results show the superiority of the above methods especially in the breast width, the Godae length, and the adaptedness to the body.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.241-246
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• 2001

This paper introduces modeling and solution for the dynamics of pipeline inspection gauge (PIG) flow in natural gas pipeline. Without of bypass flow, the dynamic behavior of the PIG depends on the different pressure between the rear and nose parts, which is generated by injected gas flow behind the tail of the PIG and expelled gas flow in front of its nose. With bypass flow, the PIG dynamics also depends on the amount of bypass flow across its body. The mathematical model are derived for unsteady compressible flow of the PIG driving and expelled gas, and for dynamics of the PIG. The bypass flow is assumed to be incompressible with the condition of its Mach number smaller than 0.45. The method of characteristic (MOC) and the Runge-Kutta method are used to solve the system governing equations. The simulation is performed with a pipeline segment in the Korea Gas Corporation (KOGAS) low pressure system, Ueijungboo-Sangye line. The simulation results show that the derived mathematical model and the proposed solution are effective for estimation the dynamics of the PIG with and without bypass flow under given operational condition.