• 산업공학
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• 제18권4호
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• pp.402-411
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• 2005

Secondary batteries with high performance are essential in widespread use of modern portable devices such as cellular phones and laptop computers. High energy density, long cycle life, and safety are some of important requirements for secondary battery. To achieve such characteristics, a mixing proportion of electrolyte solution ingredients in the battery should be carefully chosen. In this paper, using statistical design of mixture experiments (DOME), we attempt to find an optimum condition of designing the secondary battery. DOME has a distinct feature in that the experimental region is represented by simplex, rather than hypercube, because the sum of blend proportions should be unity. Several designs based upon this point have been proposed for mixture experiments. Among them, an extreme vertices design is employed in this paper because there are a couple of blend constraints to be considered. In order to investigate how the mixing proportion interacts with other manufacturing factors, a fractional factorial design is also included across the extreme vertices design. As a result, we find that the blend proportion of solution ingredients has a significant effect on battery performances. By simultaneously optimizing two battery capacities, this paper proposes an optimum blend proportion according to process factor settings.

• 한국의류학회지
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• 제30권11호
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• pp.1598-1607
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• 2006

The purpose of this study was to analyze the proportion of gathered skirts using a three-dimensional measurement system. And in this experiment, we have attempted to accumulate three-dimensional data of wearing model and find out adequate methods for analyzing shape of clothes. The experimental design consists of two factorial designs. We established three different kinds of fabrics, ratio of gathers. The measurement tool for three-dimensional model was whole body 3D scanner(Exima-WBS2H). Analysis program used in experiment is RapidForm 2004 PP1 and Pattern Design 2000. Data analysis utilizes SPSS WIN 10.0 Package. As the results show, there were different effect of gather and proportion of shapes among the measurements of width, thickness and areas made by different lines of vision in cross-sectional silhouette. And there were difference shapes of section area at each part of gathered skirts between vertical-outline silhouette and vortical-plane silhouette made by gathering conditions. And also the cross-sectional silhouettes and vertical silhouettes were related to shape of clothes.

• 산업공학
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• 제11권3호
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• pp.23-40
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• 1998

In this paper, a method to determine the optimal configuration of operating policies in an integrated-automated manufacturing system using the Taguchi method and computer simulation experiments is presented. An integrated-automated manufacturing system called direct-input-output manufacturing system(DIOMS) is described. We only consider the operational aspect of the DIOMS. Four operating policies including input sequencing control, dispatching rule for the storage/retrieval(S/R) machine, machine center-based part type selection rule, and storage assignment policy are treated as design factors. The number of machine centers, the number of part types, demand rate, processing time and the rate of each part type, vertical and horizontal speed of the S/R machine, and the size of a local buffer in the machine centers are considered as noise factors in generating various manufacturing system environment. For the performance characteristics, mean flow time and throughput are adopted. A robust design experiment with inner and outer orthogonal arrays are conducted by computer simulation, and an optimal configuration of operating policies is presented which consists of a combination of the level of each design factor. The validity of the optimal configurations is investigated by comparing their signal-to-noise ratios with those obtained with full factorial designs.

• 경영과학
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• 제31권2호
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• pp.33-48
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• 2014

It is important to maintain on operational availability of aircraft during wartime. The KF-16 fighter, the backbone of the ROKAF (Republic Of Korea Air Force), has a single engine. Therefore, the engine has a critical influence on operational availability. The purpose of this study is to estimate optimal levels of spare part inventories concerning both engines and modules. That is provided by linear programming methods utilizing a developed meta-model. For drawing out the meta-model, we develop a simulation model which can consider wartime demands. In the previous study, $2^k$ factorial design method is used to check the influence of each independent variable. That method requires relatively many scenarios because every extreme value combination of independent variables should be checked. However, this study adopts NOLH (Nearly Orthogonal Latin Hypercube) as an experimental design. By adopting NOLH, this study increases not only efficiency but also accuracy. That is proven by comparing the validity of the developed meta-model on both experimental designs. This study also utilizes the OptQuest simulation tool in ARENA to derive the optimal level of spare stocks. By comparing the result of OptQuest to that of the developed meta-model, the validity of this study is secured.

• 복식문화연구
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• 제12권3호
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• pp.354-368
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• 2004

The purpose of this study is to investigate the effect of Shirts-color(Different-color, Same-color) and Hat color(Red, Blue, Beige, Grey), Hat design (Beret, Cloche, Bowler, and Capeline) on impression formation. The experimental materials developed for this study were a set of stimulus and response scales. The 7-point semantic thirty stimuli color pictures of various combination of hair length, hair style, and type of hat design were manipulated by computer drawing. The subjects were 360 undergraduates living in Seoul, Kyunggi and Kyungnam. The experimental design was composed of 3 factorial designs. The result of the study can be summarized as follows; Impression factor of the stimulus consisted of the 5 different dimensions. (concentration of attention, attractiveness, gracefulness, activity, tenderness). Concentration of attention, elegance, and tenderness in case of a hat as a clue, elegance and tenderness in case of the color of upper clothes as a clue, and all the factors except attractiveness and elegance in case of the type of hat as a clue were significant factors to differences of appearance. In regarding the effect of interaction between each variable, the combination of Hat color and Shirts-color had significant effects on tenderness, Hat color and type of hat design on concentration of attention, elegance and activity.

• 한국의류학회지
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• 제28권3_4호
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• pp.460-471
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• 2004

The purpose of this study is to investigate the effect of hair-style (straight and wave), hair-length(short, medium, and long), and type of hat design (no-hat, beret, cloche, bowler, and capeline) on impression formation. The experimental materials developed for this study were a set of stimulus and response scales. The 7-point semantic differential response scales were designed. Thirty stimuli color pictures of various combination of hair length, hair style, and type of hat design were manipulated by computer drawing. The subjects were 360 undergraduates living in Seoul, Kyunggi and Kyungnam. The experimental design was composed of 3 factorial designs. The result of the study can be summarized as follows; Impression factor of the stimulus consisted of the 5 different dimensions (attractiveness, gracefulness, activity, concentration of attention, cuteness). Hair style greatly affected gracefulness. On the other hand, hair length made remarkable effects on attractiveness, concentration of attention, and cuteness. In addition, it has been found that the type of hat design significantly influenced on all the factors except attractiveness as independent variables. In regarding the effect of interaction between each variable, the combination of hair style and hair length had significant effects on gracefulness. In the impression formation of cuteness, the combination of hair length and type of hat design were more significant.

• International Journal of Air-Conditioning and Refrigeration
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• 제17권2호
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• pp.68-73
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• 2009

In this paper, a numerical study has been carried out to investigate the influence of volute geometries on the performance of a sirocco fan. In order to achieve an optimum volute design and explain the interactions between the different geometric configurations in the volute system, three-dimensional computational fluid dynamics and the 'design of experiment' method have been applied. Several geometric parameters, such as the volute expansion angle, the cut-off position and the bell mouth shape, are employed to improve efficiency and performance. $2^k$ factorial designs were performed to screen the most influential parameters and interactions, and showed that the cut-off position and the bell mouth shape are the most significant parameters. The optimum design was selected as a result of the response surface methodology, and effects of these parameters and their interactions were presented. From the results of computational analyses and experimental data, the performance and efficiency of the sirocco fan were successfully improved. Also, detailed effects of geometric variables of the volute system on the fan performance were discussed.

• International Journal of Fluid Machinery and Systems
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• 제4권1호
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• pp.14-24
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• 2011

In this paper, design optimization for mixed-flow pump impellers and diffusers has been studied using a commercial computational fluid dynamics (CFD) code and DOE (design of experiments). We also discussed how to improve the performance of the mixed-flow pump by designing the impeller and diffuser. Geometric design variables were defined by the vane plane development, which indicates the blade-angle distributions and length of the impeller and diffusers. The vane plane development was controlled using the blade-angle in a fixed meridional shape. First, the design optimization of the defined impeller geometric variables was achieved, and then the flow characteristics were analyzed in the point of incidence angle at the diffuser leading edge for the optimized impeller. Next, design optimizations of the defined diffuser shape variables were performed. The importance of the geometric design variables was analyzed using $2^k$ factorial designs, and the design optimization of the geometric variables was determined using the response surface method (RSM). The objective functions were defined as the total head and the total efficiency at the design flow rate. Based on the comparison of CFD results between the optimized pump and base design models, the reason for the performance improvement was discussed.

• 한국의상디자인학회지
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• 제9권3호
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• pp.19-34
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• 2007

The purpose of this research was to investigate the image dimension depending on the coloration of the Korean jacket of cromatic colors and the Korean skirt of acromatic color and to elucidate the image difference depending on the tone variation of the Korean jacket and the Korean skirt. The experimental materials used for this study were sets of stimulus and response scales(7 point semantic). The stimuli manipulated by computer simulation were 48 color pictures with various combinations of colors of jackets and skirts. The subjects were 576 female undergraduates living in Jinju city. This experiment was based on the $3{\times}4{\times}4$ factorial designs: jacket color(red, yellow and green), jacket tone(vivid, light, dull and dark), and skirt tone(N9, N7, N4 and N2). Image factor of the stimuli consisted of 4 different dimensions(youthfulness and activity, gracefulness, visibility and tenderness). Among them, the youthfulness and activity, and the gracefulness were important. According to the tone variation of Korean jacket of cromatic colors and Korean skirt of acromatic color, the images for a wearer were expressed diversely and showed the difference in image dimensions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.769-772
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• 2005

This paper deals with the aspects of die design for the multistage fine tooth hub gear in the cold forging process. In order to manufacture the cold forged product fur the precision hub gear used as the ARD 370 system of bicycle, it examines the influences of different designs on the metal flow through experiments and FE-simulation. To find the combination of design parameters which minimize the damage value, the low gear length, upper gear length and inner diameter as design parameters are considered. An orthogonal fraction factorial experiment is employed to study the influence of each parameter on the objective function or characteristics. The optimal punch shape of fine tooth hub gear is designed using the results of FE-simulation and the artificial neural network. To verify the optimal punch shape, the experiments of the cold forging of the hub gear are executed.