• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.3
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• pp.182-187
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• 2018

In this study, 20.8% of a p-type Si bifacial solar cell was used to develop a photovoltaic (PV) module to obtain the maximum power under a limited installation area. The transparent back sheet material was replaced during fabrication with a white one, which is opaque in commercial products. This is very beneficial for the generation of more electricity, owing to the additional power generation via absorption of light from the rear side. A new model is suggested herein to predict the power of the bifacial PV module by considering the backside reflections from the roof and/or environment. This model considers not only the frontside reflection, but also the nonuniformity of the backside light sources. Theoretical predictions were compared to experimental data to prove the validity of this model, the error range for which ranged from 0.32% to 8.49%. Especially, under $700W/m^2$, the error rate was as low as 2.25%. This work could provide theoretical and experimental bases for application to a distributed and microgrid network.

• Journal of the Korean Home Economics Association
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• v.27 no.3
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• pp.89-102
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• 1989

The purpose of this survey was to find out the actual conditions of living and housing needs of three generation family in the sharing apartment houses in Sang-Gye area. 1. General family type was one which is living with single parent (female), middle-aged couple and their children togeter. 2. Their main mobility to move in this houses was because of the special design of sharing apartment houses. 3. Most of actual dwelling activities of old parents and middle aged couple were performed in condition of space-integration except a few activities. 4. The "Space-compromise type" was proved as the most ideal type of three generation sharing house in our country. In which, private spaces (such as bed rooms and bath rooms) are planned to be used seperately, public spaces (such as living room and dining room) together. 5. It would be better if massionette type was taken in the case of more than 30 pyung (net area).net area).

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.856-857
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• 2008

Wave power generation as an environmentally -friendly energy has received the attention. In this paper, therefore, the tubular type Permanent Magnet Linear Synchronous Generator (PMLSG) is proposed for wave power generation. The characteristics of tubular type PMLSG are investigated by analysis using a Finite Element Analysis (FEA). Moreover, the operating performance of generator under no-load and load with variable resistance is examined. And Taguchi method is applied for considering tolerance in manufacture. The results of FEA show that proposed tubular type PMLSG is a useful solution for small-scale wave power generation.

• Journal of the Korean institute of surface engineering
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• v.47 no.4
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• pp.210-214
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• 2014

We investigated emission characteristics of tandem organic light emitting devices (OLEDs) with p-type materials as charge generation layer. The tandem OLEDs were fabricated by using $MoO_x$, $WO_x$, C60 and HATCN as p-type material or not using p-type material for charge generation. When HATCN was used as p-type material, it showed high current density at low applied voltage, but increase of efficiency was small because of charge unbalance in emitting layer. In case of tandem OLED not using p-type material, applied voltage increased remarkably because of difficulty of hole injection. In case of $MoO_x$, $WO_x$ or C60 as p-type material, current emission efficiency increased greatly. In particular, current emission efficiency of tandem OLED using $MoO_x$ as p-type material increased up to 3 times than current emission efficiency of single OLED. The Commission Internationale de l'Eclairage (CIE) 1931 color coordinates were changed by overlapping of 504 nm emission wavelength. As a result, emission efficiency of tandem OLED improved compared with single OLED, but driving voltage also increased by increase of organic layer thickness.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.6
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• pp.51-61
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• 2007

In this paper, Air-interface protocols of ISO 18000-6 Types and EPCglobal Classes applied to RFID system in UHF band are analyzed, and those anticollision algorithms are realized. Also, the each algorithm which improves the performance of standard protocol is proposed, and the performance is compared when clock period of link timing is a identical condition on $12.5{\mu}s$. As the result, when 500 tags exist simultaneously inside reader interrogation zone, the tag recognition performance of a standard protocol is better in preceding order of Class-1 Generation-1, Type B, Type A, Class-0 and Class-1 Generation-2. And also the performance of improved protocol is better in ascending order of Type B, Type A, Class-1 Generation-1, Class-0 and Class-1 Generation-2. Therefore, performance of tag recognition remarkably depends on the regulated clock period in the protocol and link timing between a reader and a tag.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.5
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• pp.39-50
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• 2018

The purpose of this study was to examine the diverse situations and housing related consciousness affecting baby boom generation's housing and to propose new possible housing alternatives for Korean baby boom generation for their old ages. Surveys were used to conduct 1:1 interviews with the baby boom generation. This study analysed the baby boom generation's housing related consciousness regarding living in old age with/apart from their children, sense of responsibility to their children and parents, expectations of support from their children in old age, current preparedness for old age, reasons for difficulties in realizing plans for housing in old age, and housing values in old age in order to examine this generation's diverse view in relation to preparations for housing in old age. Based on the results of the analysis of variables of housing consciousness in relation to old age by each characteristic of the baby boom generation conducted in investigations of the present study thus explained, housing alternatives in old age were 1)family exchange-type housing in old age 2) multihabitation-type housing in old age 3) housing in old-age with workplaces.

• Journal of Korean Elementary Science Education
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• v.33 no.3
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• pp.566-578
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• 2014

The purpose of this study is to develop a program for elementary school students' scientific experimental design knowledge generation. This study also investigated the effects of their experimental design ability, as well as the change in the type and elaborateness of their experimental design by applying the program. The subjects of this study was 4 classes in 6th grade of an elementary school located in Seoul, KOREA. The classes were divided into experimental and comparative groups. While the treatment was applied to the experimental group, the comparative group was taught using conventional methods. The pre-test and post-test for students' capability of building scientific experimental design knowledge were conducted to compare the ability of experimental design, the change in the type and elaborateness of experimental design. The findings in this study are as follows: First, the program appeared to be effective in improving experimental design ability. Furthermore, the program appeared to be more effective in generating a higher level of the experimental design type and elaborateness. Therefore, in order to improve experimental design knowledge generation ability, the program can be utilized as effective learning model in elementary school.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.5
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• pp.691-702
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• 2002

The purpose of this study was to provide basic information on the propriety of the ready to wear garment sizes of Tween Generation(ages from 5th grade to 8th grade) who has different clothing preferences in color, styles, and design and also different body sizes and shapes from younger and older students. The objectives of the study were to ascertain (a) the body figure changes occurring during Tween Generation; (b) the coverage of manufactures'garment sizes. The body measurements of elementary school students(5th & 6th grades) and junior high school students(7th & 8th grades) provide the basic statistics for this study. The mean differences of each size within each figure type are compared by using t-teats. The differences in various manufacturers'apparel sizing and figure size are investigated. Also the body measurements and the apparel sizes of the manufacturers are compared in order to evaluate the suitability of the garment size. Results indicate that the body type factors are different in each age group. And manufactures'sizes come out to be much smaller than the actual body measurements. Young casual wear can cover junior high school students satisfactorily but for elementary school students, because of low drop-value, the overall satisfaction with filling is low.

• Journal of IKEEE
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• v.5 no.2 s.9
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• pp.121-127
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• 2001

Actual system apparatuses are necessary in order to verify the efficiency and stability of photovoltaic(PV) generation systems considering the size of solar panel, the sort of converter type, and the load conditions and so on. Moreover, it is hardly possible to compare a certain MPPT control scheme with others under the exactly same weather and load conditions as well. For the purpose of solving above mentioned difficulties in a laboratory basis, a transient simulation of PV generation system using real field weather conditions is indispensable. A straightforward simulation scheme with cost effective hardware structures under real weather conditions is proposed in this paper using EMTDC type of transient analysis simulators. Firstly, a solar cell has been modeled with VI characteristic equations, and then the real field data of weather conditions are interfaced to the EMTDC through Fortran program interface method. As a result, the stability and the efficiency analysis of PV generation systems according to various hardware structures and MPPT controls are easily possible under the exactly same weather conditions.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.300-303
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• 2002

Combined generation system of Photovoltaic and wind generation have shortcoming that is different output power according to change of weather. So, the combined generation system is required backup system that such as a storage battery to supply energy, when not enough photovoltaic and wind power source for power supply equally and continually because the energy source is changeable and stable through change of weather as irradiation. temperature, wind speed. wind direction. seasons, etc.