• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.2
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• pp.111-119
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• 2019

In this study, constant power generation (CPG) algorithms are introduced for whole range power point tracking in photovoltaic systems. Currently, maximum power point tracking (MPPT) algorithm is widely used for high-power photovoltaic systems. However, MPPT algorithm cannot flexibly control such systems according to changing grid conditions. Maintaining grid stability has become important as the capacity of grid-connected photovoltaic systems is increased. CPG algorithms are required to generate the desired power depending on grid conditions. A grid-connected photovoltaic system is configured, and CPG algorithms are implemented. The performances of the implemented algorithms are compared and analyzed by experimental results.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.146-150
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• 2000

In order to prevent the defects, the optimum design of the production part, strip process layout, die design, die making and try out etc. are necessary the analysis of effective factors. For example, theory and practice of metal shearing process and it's phenomena, die structure, machine tool working for die making, die materials and it's heat treatment, metal working in field, their know how etc. are included in those factors. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. Part2 of this study reveals with ultra precision progressive die design, its making and tryout.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.121-128
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• 2012

The optimization of cooling system parameters for designing injection mold is very important to acquire the highest part quality. In this paper, the integration of computer simulations of injection molding and Analysis of Variance(ANOVA) with orthogonal array was used as a design tool to optimize the cooling system parameters aimed at minimizing the part warpage. The design optimizer was applied to find the optimum levels of cooling system parameters for a dustpan. This optimization resulted in more uniform temperature distribution over the part and significant reduction of a part warpage, showing the capability of present method as an effective design tool. The whole optimization process was performed systematically in a proper number of cooling simulations. The design optimizer can be utilized effectively in the industry practice for designing mold cooling system with less cost and time.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• Proceeding of KASS Symposium
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• 2006.05a
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• pp.175-181
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• 2006

This paper presents an efficient reanalysis algorithm, named PRAS (Partial Reanalysis algorithm using Adaptable Substructuring), for the partially changed structures. The algorithm recalculates directly any displacement or member force under consideration in real time without a full reanalysis in spite of local changes in member stiffness or connectivity. The key procedures consists of 1) partitioning the whole structure into the changed part and the unchanged part, 2) condensing the internal degrees of freedom and forming the unchanged part substructure, 3) assembling and solving the new stiffness matrix from the unchanged part substructure and the changed members.

• Journal of Korean Home Economics Education Association
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• v.13 no.1
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• pp.73-91
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• 2001

The purpose of this study was to analyze the changes in home management part in the home economics textbooks for middle school from the 1st to the 7th curriculum period. The part of home management in the all of home economics textbooks published in every curriculum period was analyzed using several external criteria of textbook. The major findings of this study were as follows : 1. The part of home management was divided into even specific areas including 'definition and process of home management'. 'time management'. 'household labor/work management'. 'family financial management'.'purchasing'. and 'consumer protection'. 2. The part of home management has been included in the middle school home economics textbooks since the 1st curriculum period. The proportion of this part in the whole textbook varied with range from 5.1% to 31.8%. 3. The areas emphasized in the beginning of curriculum period were 'family financial management'and 'household labor/work management'. and 'utilization of family resource and environment management'were the areas emphasized in the later curriculum period. 4. The titles of the middle and small unit have begun to use recent words and have represented the including contents since the 4th curriculum period. 5. The numbers of illustrations. tables. pictures. and activities have increased since the 6th curriculum period. 6. Other unrelated areas such as computer and career preparation were included in the home management part in the 1st. 2nd. and 5th curriculum period.

• Korean Journal of Human Ecology
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• v.12 no.4
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• pp.433-447
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• 2003

Since self-efficacy was suggested by Bandura(1977) as the most important factor that affects human behavior, preceding studies about self-efficacy are frequently related with children, and it is a main stream that only personal factors are chosen as related factors of these studies. Considering we don't have enough studies about family factors that reflect qualitative and relational factors of adolescents' home background, this study was aimed to seize the actual condition of self-efficacy meaning perceived and emotional faith about their own ability. These are our major concerns: 1. What kind of tendency does self-efficacy and appearance stress of adolescents, family functioning show? 2. How strong are relative influences of variables on self-efficacy of adolescents? This study was operated on July and August, 2002, aimed 378 middle school and high school students in Jeon-Nam, Mokpo area. 378 question sheets were used for analysis. Followings are results of this study. First, aimed students' average mark of self-efficacy was 2.09, which meant a normal level. And in low-ranked part, self-control-efficacy was the highest, and confidence task difficulty preference was following. Furthermore, whole self-efficacy showed a little difference from the demographic factor of adolescents. In low-ranked part, however, confidence and self-efficacy showed a somewhat difference. As students grew up, confidence decreased, and male students showed higher self-control-efficacy than female ones. Second, appearance stress and family functioning degree had a strong relation with self-efficacy. Family functioning, had important interrelation not only with whole self-efficacy but also with low-ranked part of self-efficacy. In low-ranked part, self-control-efficacy and task difficulty preference were proportional to the family functioning degree. From these results, we can find that the appearance stress was an actual factor that affected the self-efficacy of adolescents, and their self-efficacy was strongly related with family functioning degree. Accordingly, affirmative emotion in family, harmonic communication among family members and sharing housekeeping works had an immediate influence on elevation of self-efficacy.

• Journal of the Korean Geophysical Society
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• v.3 no.4
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• pp.261-268
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• 2000

Minimum magnitudes $(M_c)$ for estimation of seismicity parameters were analyzed for the earthquake catalog of Korea Meteorological Agency (KMA). The temporal variation of earthquake frequency suggests that a proper $M_c$ be 3.0 for the whole southern part of the Korean Peninsula. The b-value with $M_c$ of 3.0 is estimated to be 1.11, which is larger than those of the previous studies. To see the spatial variation of $M_c$, the southern part of the peninsula were divided into grids of $0.1{\times}0.1$ degree. At the greater portion of grid points, the local earthquake catalogs do not satisfy given statistical criteria. The grid points whose local earthquake catalogs meet the criteria mostly distribute in the eastern part. $M_c$ at these points range 2.4 to 3.5 and b values range 0.75 to 1.73 with the average of 1.08 which is comparable to that for the whole southern part of the peninsula.

• The Journal of Internal Korean Medicine
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• v.12 no.2
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• pp.52-58
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• 1991

Review of literature on the symptoms of sweat. According to comparative studies of oriental and occidental medical literature on the symptoms of sweat, following results were obtained. 1. oriental medicine 1) time: ja han (自汗), do han (盜汗) 2) body : du han (頭汗), su jog han (手足汗), sim han (心汗), eum ban (陰汗) pyun hang (偏汗) 3) kan (肝) : hwang han (黃汗), sim(心) : sin han (心汗), hyul han(血汗), bee (脾) : sig hu han (腎虛汗) sin(腎) : eum han (陰汗) By the study of the oriental medical literature, sweat were concerned with physiological function and pathological transformation of the body, 2. occidental medicine 1) NO sweat of the whole body 2) NO sweat of the part 3) much sweat of the whole body, 4) much sweat of the part. By the study of the western medical literature, sweats were tiny reaction of the· nerve and the mind.