• 태양에너지
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• 제8권2호
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• pp.26-38
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• 1988

If proper design and selection of the working fluid are made the power generation system of temperature difference could achieve more efficient results than others. This paper is to analysis the production of its power generation due to several parameters. Making the power generation system, the characteristics of power output are investigated to obtain its basic data for design. This results of this experiment are as follows. 1. The most proper working fluid in the system is Freon-22 having high stability and difference between the outlet pressure, $P_E$ of evaporator and outlet pressure, $P_c$ of Condenser. 2. With the increase of temperature difference between evaporator and condenser, the output in the system increases linearly. 3. The generation efficiency is largely dependent on the type or form of propeller, nozzle and optimum design of heat exchanger.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.1942-1947
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• 2007

A thermoelectric module can be used for cooling or power generation. The basic requirements to achieve a significant thermoelectric performance are the same for both generators and coolers. Thermoelectric modules with $Bi_2Te_3$ materials are usually employed in the cooling applications below room temperature but it can also be used for the power generation in the similar temperature range. In the present study, the power generation with a $Bi_2Te_3$ thermoelectric module has been investigated. The temperature difference between the hot and cold sides of the module is maintained with electric heater and cold water from the circulating water bath. The result shows that the electric current generated increases with temperature difference and decreases with the load resistance. However, the voltage increases with both the temperature difference and load resistance. The electric power increases with temperature difference and it has the maximum value when the load resistance is about 4 ${\Omega}$ for a given device.

• 가정과삶의질연구
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• 제20권3호
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• pp.125-138
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• 2002

The first purpose of this study is to inquire into the effect of new generation housewives'etiquette awareness on their etiquette implementation. For this purpose, this study will search the levels of new generation housewives'etiquette awareness and etiquette implementation, how the etiquette awareness and etiquette implementation vary according to their background variables, and the effect of new generation housewives'etiquette awareness as well as the background variables on their etiquette implementation. The major findings are as follows . First, the level of etiquette awareness was somewhat higher than that of etiquette implementation. Second, generally, their etiquette awareness didn't show a significant difference by the socio-demographic variables, but showed a significant difference by the psychological variables including communication level and humanism/materialism value orientation. Third, new generation housewives'etiquette implementation showed a significant difference only by monthly income like etiquette awareness. Meanwhile, as the psychological variables, etiquette implementation showed a significant difference by all Psychological variables except sex-role attitude. fourth, according to result of looking into relative influence of socio-demographic variables, psychological variables, and etiquette awareness about etiquette implementation, etiquette awareness was a significant variable which affects etiquette implementation.

• 가정과삶의질연구
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• 제14권2호
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• pp.97-110
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• 1996

The purpose of this study was to compare the caregiver burden and rewards in new generation and middle-aged couples. Data were collected from 207 new generation couples and 196 middle-aged couples who had either of older parents and lived in Seoul. Major findings are as fallows; 1. The burden were constituted with restriction of privacy physical burden strain psychological burden economic cost and guilt. The rewards were constituted with recognition pride maturity improving relationship and assistance of household and childcare. 2. The caregiver burden of new generation and middle-aged wives were hgiher than husbands. Hwever the caregiver rewards of new generation and middle-aged husbands were higher than wives. 3. The caregiver burden of middle-aged husbands were higher than new generation husbands bur there was no significant difference between new generation and middle-aged wives. 4. The caregiver rewards of middle-aged wives were higher than new generation wives but there was no significant difference between new generation and middle-aged husbands.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.169-173
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• 2016

Terahertz (THz) generation by a GaP ridge waveguide with a collinear modal phase-matching scheme based on cascaded difference frequency generation (DFG) processes is theoretically analyzed. The cascaded Stokes interaction processes and the cascaded anti-Stokes interaction processes are investigated from coupled wave equations. THz intensities and quantum conversion efficiency are calculated. Compared with non-cascaded DFG processes, THz intensities from 11-order cascaded DFG processes are increased to 5.48. The quantum conversion efficiency of 177.9% in cascaded processes can be realized, exceeding the Manley-Rowe limit.

• Current Optics and Photonics
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• 제1권2호
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• pp.138-142
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• 2017

Terahertz (THz) generation by periodically-poled $KTiOPO_4$ (PPKTP) with a quasi-phase-matching scheme based on cascaded difference frequency generation (DFG) processes is theoretically analyzed. The cascaded Stokes interaction processes and the cascaded anti-Stokes interaction processes are investigated from coupled wave equations. THz intensities and quantum conversion efficiency are calculated. Compared with non-cascaded DFG processes, THz intensities from 10-order cascaded DFG processes are increased to 5.53. The quantum conversion efficiency of 479.4% in cascaded processes, which exceeds the Manley-Rowe limit, can be realized.

• Current Optics and Photonics
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• 제2권2호
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• pp.179-184
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• 2018

Terahertz (THz) wave generation by periodically poled $BaTiO_3$ (PPBT) with a quasi-phase-matching (QPM) scheme based on cascaded difference-frequency generation (DFG) is theoretically analyzed. The cascaded DFG processes comprise cascaded Stokes and anti-Stokes processes. The calculated results indicate that the cascaded Stokes processes are stronger than the cascaded anti-Stokes processes. Compared to a noncascaded Stokes process, THz intensities from $20^{th}$-order cascaded Stokes processes increase by a factor of 30. THz waves with a maximum intensity of $0.37MW/mm^2$ can be generated by $20^{th}$-order cascaded DFG processes when the optical intensity is $10MW/mm^2$, corresponding to a quantum conversion efficiency of 1033%. The high quantum conversion efficiency of 1033% exceeds the Manley-Rowe limit, which indicates that PPBT is an excellent crystal for THz wave generation via cascaded DFG.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.9-12
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• 2005

This paper investigated the temperature history of mass concrete mock up structure considering different heat generation by varying with mixture proportion. Setting time difference between high early strength mixture (E-P) and retarding mixture (R-F30) was 14.5hours. Incorporation of $30\%$ of fly ash contributed to $10^{\circ}C$ of hydration heat reduction. In generally used C and D combination, bottom concrete shows earlier hydration, while E-J combination showed reverse tendency and thus, this method can reduce the crack occurrence. Therefore, heat generation difference method has beneficial effect on reducing crack induced by hydration heat resulting from heat generation difference between surface and center section.

• 대한전자공학회논문지
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• 제13권3호
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• pp.1-6
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• 1976

이 논문에서는 Boolean difference를 이용하여 combinational 및 sequential 논리회로에서 발생하는 기능적인 고장에 대한 test pattern을 얻는 방법을 연구하였다. 이 방법은 test pattern을 얻고자 하는 회로의 Boolean 함수의 Boolean difference를 계산하므로써 체계적으로 test pattern을 얻는 절차를 보여주고 있다. 컴퓨터에 의한 실험결과에 의하며 이 방법은 combinational 회로 및 asynchronous sequential 회로에 적합하며, clock이 있는 flip flop을 적당히 모형화함으로서 이 방법을 synchronous sequential회로에도 적용할 수 있음이 입증되었다. In this paper, a method of test pattern generation for the functional failure in both combinational and sequentlal logic networks by using exterded Boole an difference is proposed. The proposed technique provides a systematic approach for the test pattern generation procedure by computing Boolean difference of the Boolean function that represents the Logic network for which the test patterns are to be generated. The computer experimental results show that the proposed method is suitable for both combinational and asynchronous sequential logic networks. Suitable models of clocked flip flops may make it possible for one to extend this method to synchronous sequential logic networks.

• 한국의류산업학회지
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• 제25권3호
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• pp.267-279
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• 2023

The current bra market and the purchasing behavior of women of the MZ generation in Korea are reviewed in this study. Therefore, basic data for bra product planning for women of the MZ generation are presented by investigating the wearing status and satisfaction. Through online surveys, 272 questionnaires were obtained and were analyzed through frequency analysis, cross-analysis, t-test, and variance analysis. Generation M and Generation Z share digital culture, but, due to age differences, they are compared by generation. There was, however, little significant difference between these groups. In addition, there was no significant difference between groups when factoring for the time of wearing, place of purchase, and material of bras. However, there were big differences between groups depending on whether bras had wires, lace, and their size, especially in body correction items. According to the results, it is pointless to target each generation when making a bra. Also, the young generation consumers are more interested in functionality than in the design compared to 10 years ago. It will improve consumer satisfaction if two different types of bras are produced; one that corrects the body and one that fits well even if the body is less corrected.