• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.12
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• pp.84-89
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• 2010

In this paper, a novel voltage-controlled oscillator (VCO) using the microstrip square open loop dual split ring resonator is presented for reducing the phase noise. The square-shaped dual split ring resonator having the form of the microstrip square open loop is investigated to reduce the phase noise. Compared with the microstrip square open loop resonator and the microstrip square open loop split ring resonator as well as the conventional microstrip line resonator, the microstrip square dual split ring resonator has the larger coupling coefficient value, which makes a higher Q value, and has reduced the phase noise of VCO. The VCO with 1.7V power supply has the phase noise of -123.2~-122.0 dBc/Hz @ 100 kHz in the tuning range, 11.74~11.75 GHz. The figure of merit (FOM) of this VCO is-214.8~-221.7 dBc/Hz dBc/Hz @ 100 kHz in the same tuning range. Compared with VCO using the conventional microstrip line resonator, VCO using microstrip square open loop resonator, the phase noise of VCO using the proposed resonator has been improved in 26 dB, 10 dB, respectively.

• Korean Journal of Social Welfare
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• v.61 no.2
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• pp.33-60
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• 2009

This study aimed at examining whether the national rental housing supplied by Korea National Housing Corporation (KNHC) is truly contributing to the upward mobility of housing in low-income households without their own house by comparatively analyzing whether those who moved out of the national rental housing made upward, horizontal or downward housing type mobility. The subjects of this study included 333 people who had moved out of three national rental housing complexes in Cheongju, Chungcheongbuk-do in 2007, which had opened to the first residents two years ago. A telephone survey involving the subjects was carried out. Collected data were analyzed through frequency analysis, cross tabulation analysis and multiple regression analysis, with using the type of residential mobility(downward mobility, horizontal mobility or upward mobility) according to "housing size" and "housing costs" as a dependent variable, and personal and family environment and economic environment as independent variables. According to the results of the analysis, 76.4% of the households made an upward mobility, 1.6% remained little changed, and 22% moved downward in terms of "housing costs," compared to before moving into the national rental housing and while living there. Furthermore, in terms of "housing size" 61.8% of the households moved upward, 16.5% remained little changed and 19.7% moved downward. The variables affecting the upward mobility of housing type included the number of income earners in a household, income earner's occupation and education level. Income earner's amount of income, age and family to support, on the other hand, turned out to have little effect on the upward mobility. Based on the results of the study, the following suggests were made for the supply of effective national rental housing. First, various features of each type of residential mobility should be reflected. Second, national rental housing residents' self-sufficiency should be enhanced to help them move upward in housing type.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.6
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• pp.679-685
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• 2011

This paper presents an algorithm identifying devices that generate observed mixed signals that are collected at main power-supply line. The proposed algorithm, which is necessary for low cost electric power monitoring system at appliance-level, that is non-intrusive load monitoring system, divides incoming mixed signal into multiple time intervals, calculating difference-signals between consecutive time interval, and identifies which device is operating at the time interval by analysing the difference-signals. Since the features of one device can remain when the time interval is short enough and the features are independent and additive, well-known classification algorithms can be used to classify the difference-signals with features of N individual devices, otherwise $2^N$ features might be necessary. The proposed algorithm was verified using data mixed in a laboratory with individual devices's data collected from field. When maximum 4 devices operate or stop sequentially and when features satisfy the requirements of proposed algorithm, the proposed algorithm resulted nearly 100% success rate under the constrained test condition. In order to apply the proposed algorithm in real world, the number devices shall increase, the time interval shall be smaller and the pattern of mixture shall be more diverse. However we can expect, if features used follow guidelines of proposed algorithm, future system could have certain level of performance without the guideline.

• Journal of the Korean Home Economics Association
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• v.48 no.1
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• pp.83-96
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• 2010

This study was conducted to derive useful predictive variations for the qualitative supply of homes to provide information to real estate venture businesses and other business owners in neighborhood amenities and significant basic information to housing suppliers and policy makers. For this purpose, a number of apartment dwellers in Seoul were surveyed to examine their housing satisfaction, difference in housing satisfaction according to variables, and any relevant correlations. In detail, 500 apartment dwellers in Seoul were surveyed from September 1, 2009 to September 20, 2009 to gather resources that were processed through SPSS 14.0 to find percentage of frequency, mean, standard deviations, t-test, ANOVA, and Duncan Multiple Ranger's Test. The following were the findings of this study: First, housing satisfaction of apartment dwellers in Seoul was above average with the highest satisfaction with neighborhood environment. Second, satisfaction with amenities was significantly affected by dweller-related variables. Gangnam dwellers were more satisfied with housing environment and community environment than Gangbuk dwellers. By age, people in 20s and 30s showed high satisfaction with housing environment. Satisfaction with community environment was high among 20s, 30s and 40s. Satisfaction with management conditions was high among 20s. Also, satisfaction was high when housing period was between 1 and 10 years. By size, dwellers in 40py or larger homes showed high satisfaction with housing environment and management conditions. Dwellers in 30py and 40py or larger homes were satisfied with community environment. By ownership, dwellers with ownership of their homes showed high satisfaction. Third, there was a significant difference in satisfaction with neighborhood and social environments according to dweller-related variables. By region, dwellers of Gangnam area showed high satisfaction with neighborhood environment. By age, people in 20s, 30s and 40s showed high satisfaction with neighborhood environment. Also, satisfaction with neighborhood environment was high when housing period was around 10 years. By size, dwellers in 30py and 40py or larger homes were satisfied with neighborhood and social environments. Fourth, there was a close correlation between satisfaction with housing environment and satisfaction with community environment, and between satisfaction with community environment and satisfaction with management conditions. Thus, most dwellers that were satisfied with one variable of housing environment showed high satisfaction with other variables.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7656-7666
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• 2015

The purpose of this study was to explore the determinants of subjective happiness among Korean adolescents and to supply basic data for enhancing to subjective happiness among Korean adolescents. This study used the 2014 Korean Youth Health Risk Behavior On-lin Survey data. It conducted a secondary data analysis of 72,060 cases. It conducted frequency analysis, t-test, ANOVA and multiple regression analysis by SPSS 18.0. Although various independent variables influenced on emotional support(t=44.335, p<,001), gender(t=27.730, p<.001), grade(t=25.347, p<.001), economic status(t=-25.345, p<.001), living arrangement(t=-6.158, p<.001), school record(t=-7.512, p<.001), father's educational status(t=-2.378, p<.001), subjective health status(t=46.062, p<.001), depression(t=-23.837, p<.001), sleep(t=19.871, p<.001), level of stress(t=-78.685, p<.001), alcohol(t=-13.481, p<.001) and drug use(t=-2.671, p<.01), smoking(t=-11.988, p<.001), breakfast(t=4.443, p<.001), activity(t=4.757, p<.001) were key factors of subjective happiness among Korean adolescents. The findings of this study were as follow: male middle students, who had emotional support, higher economic status, school record and father's educational level, living with family showed higher levels of subjective happiness. It also having good subjective health status, not depressed, more sufficient sleep, lower stress, no experience of drinking, smoking and drugs, more physical activity and having breakfast showed higher levels of subjective happiness.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.355-362
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• 2018

This study was performed to develop the mass propagation system using tissue culture technique to supply the seeds of Elephant garlic (Allium ampeloprasum L.) which has difficulty in propagation. Immature spathe of Elephant garlic was cultured on Murashige & Skoog (MS) medium supplemented with two plant growth regulators, naphthaleneacetic acid (NAA) and kinetin. After 6 weeks of culture, the highest number of shoot (14.9/explant) was obtained when the immature spathe with 10 cm length was cultured right after harvesting. In MS medium supplemented with 2 mg/L kinetin and 0.5 mg/L NAA, the most vigorous growth characteristics was observed, the shoot number was 14.9/explant, its length was 11.3 cm, and its fresh weight was 2.5 g. When the bulblets were cultured in MS medium with 2 mg/L kinetin and 0.5 mg/L NAA, the addition of 30 mg/L adenine improved their proliferation and growth significantly, the highest bulblet formation rate (48%) was obtained. The addition of 7% sucrose also increased the bulblet formation rate at the highest frequency of 98.2%. The shoots were shown be more vigorously proliferated at the secondary subculture stage rather than primary culture stage, their propagation rate was 80% after subculture.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.440-452
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• 2021

This study identified and evaluated conditions for continued participation of private forest owners in forest carbon offset programs. The probability of continuing forest carbon offset projects, which delays greenhouse gas emissions by extending harvesting periods, increases with increasing price of carbon offset credits, public recognition of forest value, and education level. Willingness to Accept (WTA) was estimated using a Multiple Bounded Dichotomous Choice Question, which was 17,039 KRW/tCO₂ for extending age to 60 years, and 23,070 KRW/tCO₂ for 100 years. The following findings aim to promote participation and supply of carbon offset programs in private forests according to the study outcomes. First, introducing policies supporting private forest owners bearing opportunity costs for avoiding greenhouse gas emissions by postponing timber harvest is needed. Second, educational programs for private forest owners whose awareness of and interests in the public value of forest is necessary. Third, although having participated from the beginning of the offset program, finding ways to lead continuous participation of forest owners who are less likely to accept WTA is also necessary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.350-356
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• 2018

The contact force, which is the dynamic interaction between the pantograph and the catenary, is an important indicator for evaluating the current collecting quality, which is a stable power supply characteristic to the vehicle. In this study, dynamic contact force characteristics of pantograph of HEMU-430X vehicle, which is a power-distributed high-speed train test vehicle, were analyzed according to the catenary tension and compared with the analytical results using the pantograph-catenary interaction model. As a result of comparing the test results with the analytical results, it was confirmed that the average contact force and the standard deviation of the contact force, which are the main dynamic contact force characteristics, coincide relatively well. Using the analytical model, the relationship between the catenary tension and the contact force is presented according to the vehicle speed, and the optimal catenary tension for each operation speed is presented and compared with the international standard. As a result, it was found that the results obtained from the analysis are comparable to those recommended by international standards.

• Journal of Cadastre & Land InformatiX
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• v.49 no.1
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• pp.123-144
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• 2019

The purpose of this study is to grasp factors the increasing population growth rate of the region through the regional and housing market characteristics. This paper has used multiple regression as the dependent variable (average of the population growth rate of 85cities during the last five years) and the independent variables analyzed the regional and housing market characteristics on the average. The results of the analysis, The regional and housing market variables that have had a significant impact on the regional population growth rate over the last five years are birth rate, employment rate, production available population growth rate, apartment rate, resale rights rate, and apartment turnover rate and the number of businesses per thousand and has decreased. In other words, The regions where the population increased by region for the last five years were the ones with the transfer of public institutions (innovation cities) and land development among the Seoul metropolitan area and non-Seoul metropolitan area excluding Seoul and metropolitan cities. The results of this study is intentional to suggest Policy point of view for the balanced regional development presented at the government level for other the metropolitan area, such as the small and medium cities that are undergoing population decline.

• Journal of Life Science
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• v.31 no.8
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• pp.778-785
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• 2021

The germination of cucumber seeds begins with the degradation of reserved oil to fatty acids within the lipid body, which are then further metabolized to acyl-CoA. The acyl-CoA moves from the lipid body to the glyoxysome following β-oxidation for the production of acetyl-CoA. As an initial carbon source supplier, acetyl-CoA is an essential molecule in the glyoxylate cycle within the glyoxysome, which produces the metabolic intermediates of citrate and malate, among others. The glyoxylate cycle is a necessary metabolic pathway for oil seed plant germination because it produces the metabolic intermediates for the tricarboxylic acid (TCA) cycle and for gluconeogenesis, such as the oxaloacetate, which moves to the cytosol for the initiation of gluconeogenesis by phophoenolpyruvate carboxykinase (PEPCK). Following reserved oil mobilization, the production and transport of various metabolic intermediates are involved in the coordinated operation and activation of multiple metabolic pathways to supply directly usable carbohydrate in the form of glucose. Furthermore, corresponding gene expression regulation compatibly transforms the microbody to glyoxysome, which contains the organelle-specific malate synthase (MS) and isocitrate lyase (ICL) enzymes during oil seed germination. Together with glyoxylate cycle, carnitine, which mediates the supplementary route of the acetyl-CoA transport mechanism via the mitochondrial BOU (A BOUT DE SOUFFLE) system, possibly plays a secondary role in lipid metabolism for enhanced plant development.