• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1075-1080
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• 2021

In this paper, we designed a 24.4GHz 2-channel TX and 4-channel RX patch array antenna mounted on a short-range vehicle radar system to simultaneously measure the range and speed of a single object within a single measurement cycle. The antenna was designed and fabricated using Rogers' RO4350B(ε_r=3.48, 0.5T) board. Through measurement, it was confirmed that the design specifications of antenna gain (> 10dBi or more) and radiation pattern (Elevation HPBW > 10deg.) were satisfied at 24.4 GHz frequency.

• Korean Journal of Human Ecology
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• v.23 no.6
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• pp.1191-1204
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• 2014

Even though a Han-bok, or traditional Korean costume, should be inherited since it is invaluable part of our culture, research on Han-bok is scarce. Since the development of a Jeogori pattern, the upper garment of Korean traditional clothes, is done mostly based on the chest size, the design does not completely consider on wearer's body shape. Moreover, unless made by an expert, trial and error is almost always necessary to improve the fit of the clothes. In this research, a Jeogori pattern was suggested that improves the fit based on the shape of the upper back(straight or bent) of a female in her late 20s who often wears a Han-bok and is comfortable when moving. Using a 3D virtual clothing system, the optimum pattern was selected based on the body shape. The final selection was made, and each subjects tried the garment on to evaluate the comfort when moving, along with its appearance, based on a seven point Likert scale. As a result, for a straight body shape, the optimum ease for the front bust width was 2.5cm, and that for the back bust width was 2.0cm. The optimum center back dart was 1.0cm. The optimum Geodae width was 7.6cm, and the optimum back Geodae point was 2.0cm. For the bent body shape, the optimum ease for the front and back bust was 2.0cm. The optimum Geodae width was 8.4cm, and the optimum back Geodae point was 1.5cm. Furthermore, if the Hwajang slope was set at half of the vertical distance between the laterals of the neck and shoulder, a fitted silhouette appeared, which is preferred nowadays. In the appearance evaluation, the final pattern designed in this research received higher scores than the original design(straight; p<.001, bent; p<.05). The results of the evaluation of the comfort when moving also showed higher scores for the final pattern that was designed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.31-36
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• 2014

A study on the indoor positioning system has been active recently for the location based service indoors. In the 3 dimensional positioning system based on the acoustic signal and TDOA technology, the error characteristics of the estimated source position would be changed depending on the number of microphones and the pattern of the microphone array. In this paper, the estimated position error according to the measured distance error between the microphones and the signal source is analyzed, and the optimum microphone array is decided considering the estimated position error patterns and the total amount of the estimated position error.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.4
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• pp.149-166
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• 2021

This study tried to suggest a drafting method to draft tight fit torso patterns suitable for adult males with a sway back somatotype and a bend forward somatotype by setting and distributing the ease through the completion of the somatic surface pattern using the 3D body surface segment method. It was intended to be presented as a drafting method. As for the research method, the suitability of the somatic surface patterns and the tight fit torso patterns were confirmed by the evaluation of virtual wear, and the patterns were modified and supplemented. The research results are as follows. In the first evaluation of the tight fit torso patterns, the average, for 55 evaluation items, was 3.92 points for the sway back somatotype and 3.89 points for the bend forward somatotype. In the second evaluation, the bend forward somatotype was 4.51 points and the sway back somatotype was 4.62 points. The chest circumference ease amount for the bend forward somatotype and the sway back somatotype are 6.5% (6.8 cm) and 7% (6.8 cm) of the chest circumference, respectively, and the distribution of the front and back ease is the same at 4:6 (2.72 cm:4.08 cm). The waist circumference ease amount is 6.5% (5.8cm) and 6.5% (5.6 cm) of the waist circumference dimensions, and the distribution of the front and backease are 5:5 (1.45 cm: 1.45 cm) and 4:6 (2.24 cm: 3.36 cm), respectively. The completed tight fit torso patterns were converted into institutional formulas and presented as a drafting method.

• Journal of Institute of Convergence Technology
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• v.1 no.1
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• pp.34-40
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• 2011

In this paper, a hybrid design tool combining one-dimensional(1D) lumped model and three-dimensional computational fluid dynamics(CFD) approach has been developed in order to evaluate the performance of inkjet print head and droplet control process are studied to reduce the deviations between nozzles which affect the size of the printed line for the industrial application of direct writing on printed circuit boards(PCB). 1D lumped model analysis shows that it is useful tool for evaluating performance of an inkjet head by varying the design parameters. The differences in ejected volume and droplet velocity between analytical and experimental result are within 12%. Time sequence of droplet generation is verified by the comparison between 3D analysis result and photographic images acquired by stroboscopic technique. In addition, by applying DPN process, velocity and volume uniformity between nozzles is dramatically improved that the tolerance achieved by the piezoelectric inkjet printhead across the 64 nozzles is 5 to 8%. A printed line pattern is successfully obtained using the fabricated inkjet print head and droplet calibration system.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.85-92
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• 2022

In this study, we aim to design an action game that increases the user experience. In order to increase the immersion of the game, the characteristics of the game used by the user were analyzed, and the systemic and visual characteristics of the game were designed with reference to each characteristic. The proposed method uses Unity 3D to implement an interaction system between objects in the game and is designed in a way that allows users to immerse themselves in the game. To induce immersion through the visual elements of the game, 2D objects and players are placed in a 3D space, and a 2D dynamic light shader is added. It is composed of inter-combat rules and monster behavior pattern collision detection and event detection. The proposed method contained the user experience with the implementation thesis, and showed the game's possibility of leading the user's affordance.

• Journal of Power System Engineering
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• v.18 no.3
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• pp.51-58
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• 2014

Injection molding simulation provided optimized design results by analyzing quality problems while the product is in assembly or in the process of manufacturing with make automobile plastics. Frequent change of design, change of injection molding, repetition of test injection which was held in the old way can now be stopped. And quality upgrade is expected instead. This report deals with the effect which the position of injection molding automobile console gate and number has on product quality including pressure at end of fill, bulk temperature at end of fill, shear stress of end of fill, residual stress at post filling end, product weld lines and warpage results. Simpoe-Mold simulates the complete manufacturing process of plastic injected parts, from filling to warpage. Simpoe-Mold users, whether they are product designers, mold makers or part manufacturers, can identify early into the design stage potential manufacturing problems, study alternative solutions and directly assess the impact of such part modification, whatever the complexity and geometry of such parts, shell part as plain solid parts.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.212-223
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• 1995

To improve the efficiency of a power transmission system with slip elements, power split/circulation system is applied. The performance of a power split/circulation system varies widely by the change of the followings; the layout of system, the type and gear ratio of planetary gear, the performance of slip element, etc. Therefore, when one designs such a power transmission system or when one determines the economic/power mode of system, a certain performance prediction method is needed. In this study, the internal power flow pattern of a power split/circulation system is theoretically analyzed on several transmission systems. And an effective performance prediction method(so called performance locus diagram) is presented. By this method, the effects of design factors can be easily understood and the qualitative performances of system can be clearly evaluated.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.4
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• pp.701-715
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• 2016

This research compared 3 types of jacket pattern design methods for men's wear (age range 25-35) in textbooks. We are to develop research pattern with problem solving based on an analysis of three jacket patterns. The comparative analysis revealed that loose-silhouette slopers A and B scored high in functional evaluation and low in appearance evaluation. However, the tight-silhouette slim-line sloper C received high points in appearance evaluation, but low scores in functional evaluation. All three slopers were evaluated low in the back appearance. The design characteristics of the development jacket sloper were: front width, ($1/10chest{\times}2$)+0.8cm; side width, 1/10 chest+5.5cm; back width, ($1/10chest{\times}2$)+1.5cm; armscye depth, 1/8 chest+11cm; waist back length, 1/2 jacket length+5cm; and hip length, 1/2 (jacket length-waist length)+1cm. The proportions against jacket length were applied to waist length, hip length, and the position of chest/waist pockets. In addition, the back part with low appearance estimation was adjusted as comfortable with the back curve line. Appearance evaluation and 3D clothes modeling system (CLO) showed an overall improvement in the developed jacket sloper when compared to the original jacket slopers.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.9 s.174
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• pp.137-146
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• 2005

This paper describes a research work to develop a computer-aided design for the product made by progressive working of bending and piercing. An approach to the system for progressive working is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of three main modules, which are input and shape treatment, flat pattern layout, strip layout modules. The system is designed by considering several factors, such as piercing and bending sequences by fuzzy set theory, complexities of blank geometry, punch profiles, and the availability of a press equipment. Strip layout drawing generated in the strip layout module is presented in 3-D graphic forms, including piercing and bending sequences with punch profiles divided into for external area. Results obtained using the modules enable the manufacturer for progressive working of electric products to be more efficient in this field.