• Journal of the Korean Society for Precision Engineering
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• 제17권6호
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• pp.162-168
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• 2000

The automatic die polishing machine by liquid honing has been developed and experimented on the surface of machined die. The goal of development in the automatic die polishing machine by liquid honing is to increase the accuracy and the productivity in die polishing. To reach this goal, the polishing machine consists of the automatic measuring device for contour of die, the nozzle and pumping system to spray the powder mixed with liquid, and the 3-axis guides. Before polishing, the measuring device with a semiconductor laser scans the surface of mould to get the data of contour. The data store a PC and use to control the nozzle head to move above a couple of centimeters on the machined surface of die. The experimental parameters are the spraying time, the pressure, the size of abrasive grain and the mixing ratio between abrasive grain and liquid. The surface roughness is measured on the polished die which are SKDl 1 and Al7075 machined by NC. The surface roughness indicates the values of Rmax 0.5${\mu}{\textrm}{m}$ for Al7075 and Rmax 1.4${\mu}{\textrm}{m}$ for SKDl 1. It reduces the polishing time significantly and reduces the monotonous work for labors. As the results, the liquid honing system is useful method to apply for the die polishing and the automatic die polishing machine using liquid honing shows that it's very effective processing ability.

• Journal of the Korean Society for Precision Engineering
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• 제29권10호
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• pp.1078-1088
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• 2012

In this paper, we present research experimental results about the different thickness T-joint welding of the high power continuous wave(CW) Nd:YAG laser for the secondary battery of a vehicle. Although the conventional method used for the secondary battery is a argon TIG welding, we utilize a laser welding to improve Tungsten Inert Gas(TIG) welding's weakness. The laser, which has a couple of advantage such as aspect ratio, low Heat Affected Zone(HAZ), good welding quality and fast productivity utilized in this work is a CW Nd:YAG laser. In order to observe laser welding sections, we used a optical microscope. Through the analysis of the metallographic, hardness, aspect ratio, and heat input, we obtained the desired data in condition of 1800 W laser beam power and 1.8 m/min and 2.0 m/min laser beam travel speeds. In order to compare electric resistances of the argon TIG welding and laser welding, we made an actual battery and the electric resistance of the laser welding is reduced by 40~45% comparing with the argon TIG welding.

• Proceedings of the KIEE Conference
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.228-230
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• 2002

Recently, electric power reliability of our country has been improved. However, there are still remaining problems which are short-duration variations like instantaneous and momentary interruption and voltage sag by nature calamity ; typhoon, lightning, snow, etc. Besides, power quality ; harmonics, caused by using power electronics equipments, become a hot issue Malfunction of controller and stop machinery, and losing the important data are caused by poor power quality at a couple of second. Due to those, UPS, which is made up battery, has being used, but there are several disadvantages ; long charge and discharge time, environmental problem by acid and heavy metal, and short life time. As generally know, micro-SMES is a method to settle those mentioned. However, there need huge system apparatuses in order to verify the effect of system efficiency and stability considering the size of micro-SMES, the sort of converter type, and various conditions ; inner temperature, magnetic field, quench characteristic of micro-SMES, and etc. In this paper, in order to bring the mentioned above to a settlement, a micro-SMES is modeled with characteristics of micro-SMES is interfaced to EMTOC program using Fortran program interface method. We obtained hopeful answers and made the simulation model of micro SMES.

• Journal of Korea Society of Digital Industry and Information Management
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• 제8권4호
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• pp.205-215
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• 2012

Due to a rapid change of business environment, many firms are eager to find the competitiveness by information technology adoption and diffusion. In this exploratory study, we examined the applicability of a previously proposed model to evaluate IT competitiveness based on the innovativeness and verified it's propriety with empirical data. As suggested by previous studies, the proposed model considers a variety of corporate and market characteristics concerned with IT adoption, and it consists of several internal and external impacting factors, which have influence on technology diffusion and its performance. For the empirical analysis, the survey data of domestic ERP adoption cases were adopted from 128 small and medium-sized enterprises(: SMEs) in IT and electrical engineering industry, and analyzed by partial least squares(: PLS) - a popular structural modeling and multivariate projection technique to latent variables. The results indicated positive supports for the research model of external and internal IT adoption factors' influences on innovativeness' performances. However, there are a couple of limitations not to show the reliability of selected measurement items and the generality of model proposed in this exploratory study.

• Solar Energy
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• 제19권3호
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• pp.85-91
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• 1999

This study represented experimental research on the flat-plate solar collector. The heat performances were measured the tube array surface temperature by thermal-couple. The solar collector($W{\times}H$) of $580{\times}1100$, various tilt angles of 30, 45, 60 degree and the internal tube number of 4, 6, 8, 10(ea) were utilized in the present investigation. It is found that the thermal concentration is higher as the tilt angle become larger and the solar tubes are more and more. In this stuby obtained results of following: The array of tubes in collector has the best nice in that the number of tube is eight and the tilt angle is 60 degree. The collect energy by each tube array shown high value by increase the number of tubes and tilt angles. In addition to, the collect energy depends on by the tilt angle than the number of tube.

• Journal of the Korean Society of Food Culture
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• 제15권2호
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• pp.123-137
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• 2000

Korea market of food service industry has been increased greatly since early 90's with the emergence of professional catering business and the expansion of school food service. Because of the characteristics of food service establishment, feeding many people at a time, there is always a high potential of foodborne outbreak which requires special sanitary management to prevent. Currently, many catering businesses are interested in HACCP(Hazard Analysis Critical Control Points), a new sanitary management system, and are trying to develop HACCP Plans for their food service establishment. Microbiological hazard analysis, a most important step for developing HACCP Plan, provides also basic information for evaluating sanitary aspect of prepared foods and their materials. There are not extensive data of microbiological hazard analysis for food service operations, especially for prepared foods and raw materials, which are helpful for developing a HACCP Plan. The extensive microbiological hazard analyses for 65 prepared foods and 51 raw materials selected from a couple of food service establishment were performed in this research. These results will provide useful information to determine hazards for developing a HACCP plan, and also to understand sanitary status for prepared foods and raw materials in food service establishment.

• Steel and Composite Structures
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• 제38권5호
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• pp.583-597
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• 2021

This article develops a nonclassical model to analyze bending response of squared perforated microbeams considering the coupled effect of microstructure and surface stress under different loading and boundary conditions, those are not be studied before. The corresponding material and geometrical characteristics of regularly squared perforated beams relative to fully filled beam are obtained analytically. The modified couple stress and the modified Gurtin-Murdoch surface elasticity models are adopted to incorporate the microstructure as well as the surface energy effects. The differential equations of equilibrium including the Poisson's effect are derived based on minimum potential energy. Exact closed form solution is obtained for bending behavior of the proposed model considering the classical and nonclassical boundary conditions for both uniformly distributed and concentrated loads. The proposed model is verified with results available in the literature. Influences of the microstructure length scale parameter, surface energy, beam thickness, boundary and loading conditions on the bending behavior of perforated microbeams are investigated. It is observed that microstructure and surface parameters are vital in investigation of the bending behavior of perforated microbeams. The obtained results are supportive for the design, analysis and manufacturing of perforated nanobeams that commonly used in nanoactuators, nanoswitches, MEMS and NEMS systems.

• Korean Journal of Social Welfare
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• 제61권1호
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• pp.293-322
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• 2009

This study investigated the problems of remarried wife with alcoholic problem. Specifically, this study regarded the wife's alcoholic problem as the problems of dysfunctional interaction among family members rather than an individual problem. The study had three purposes as follows. First, what were the interactions sustaining the conflict of remarried family? Second, what were the characteristics of remarried family relating to family conflict? Third, what were the interventions of family therapy to resolve the conflicts of remarried family? The total family counseling was 9 sessions, which included individual, couple, and family counseling. The study used constant comparative analysis by using open coding method to find the factors relating interactions sustaining the conflict of remarried family, the characteristics of remarried family relating to family conflict, and the interventions of family therapy to resolve the conflicts of remarried family. Also, the study used Miles and Huberman's matrix and graphical network display to show the interaction of family members. The study found intriguing factors, counteracting factors, relationship level, and relational elements to wife's alcoholic problems among family members. The study revealed husband's rigid family rules, husband's execution of patriarchal authority, husband's pursuit of family identity, and husband's emphasis of union among family members as the characteristics of remarried family. On the other hand, the study found the reinforcement of spousal subsystem, the pursuit of change in communication pattern between husband and wife, the amelioration of rigid family rules, and the acceptance of differences among family members as the intervention of family therapy to resolve the conflicts of remarried family.

• Journal of the Korea Fashion and Costume Design Association
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• 제13권1호
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• pp.113-123
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• 2011

The purposes of this study were to re-interpret the Traditional Korean Painting of Flower and Bird Patterns from a modern point of view and use them in apparel textile design. A literature review of the Traditional Korean Painting of Flower and Bird Patterns was made first, and then, through manual and Photoshop workings, two apparel textile designs were suggested. The results were as follows. First, Traditional Korean Paintings of Birds and Flowers are covered not only by decorative beauty but also by the common pure hope and ideology of loving and adoring nature, which is inherent in the symbolism and racial characteristics and high aesthetic sense appeared by ancestors' life feeling. The meaning that is symbolized by each subject matter appearing in the Transcontinental Painting of Bird and Flower is important, but the ancestors' deeper and affectionate desire is shown in the harmony and happy aspect of a picture where more than two subject matters appear, such as Song Hak do where pine is with crane, cockscomb with chicken, bamboo with beacon fire, or a couple of them with flower. Second, two kinds of textile designs were suggested. The motif of work 1 targeted professional women of activity and individuality in their late 30s to early 40s. The lotus blossom pattern was selected to present its concept, "Chic Elegance." The motif of work 2 targeted intelligent women in their mid 40s, and the peony blossom was selected to present its concept, "Romantic Elegance."

• The Journal of the Korea Contents Association
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• 제15권9호
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• pp.184-194
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• 2015

The present study set out to investigate influencing factors on family strength. The sample consisted of 249 male and female married adults who were in the class of social welfare in S cyber university. Analysis revealed that married adults' family strength level was 3.86(above the moderate). Among variables, marital status, religion, income, economic problems couple conflict, conflict with mother-in-law, children's problem, family of origin experiences were associated with family strength. Regression analysis revealed that family cooperation and harmony of family were associated with family strength among 8 sub-factors : overall emotional health of family, conflict resolution, acceptance of separation and loss, permission to others, harmony of family, family cooperation, independence in extended family, power balance in family. These findings highlight the collective characteristics of Korean family and traditional values emphasizing the harmony influences the family strength through the generation.