• Journal of Digital Convergence
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• v.12 no.3
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• pp.1-6
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• 2014

This paper examines the relationship between education and marriage in South Korea, based on a 2 percent data of the 2000 census. The result found strong educational homogamy and wife-hypergamy over the five age cohort, 21-30, 31-40, 41-50, 51-60, and 61-70. For the primary, junior secondary, upper secondary and tertiary educational levels, the chance of marrying within the same educational level was stronger for primary and tertiary education. In terms of trends, the educational homogamy increased across the four cohorts. We note that while upward marriage was stronger for women (hypergamy), it decreased over time.

• 주택과사람들
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• s.193
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• pp.98-103
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• 2006

최근 이스탄불의 골든혼 해협에서 보스포러스 해협으로 이어지는 신시가지의 부동산 시장이 초강세를 보이고 있다. 2005년 10월에 시작된 유럽연합 가입 협상을 계기로 터기의 부동산 시장이 본격적인 상승 탄력을 받으며 세계의 주목을 받기 시작한 것. 보스포러스 해협 주변에는 고급주택 및 신축 붐이 일고 있고 고층 아파트 위주로 가격이 상승하고 있는 이스탄불의 주택 시장을 직접 취재했다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.4 s.119
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• pp.430-439
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• 2007

In this paper, we propose a broadband TEM horn antenna optimized using a genetic algorithm. The characteristics required for the TEM horn are the broad matching bandwidth from 2 GHz to 10 GHz and high gain in broadside with a small gain deviation within that bandwidth. In addition, a broadband balun is designed to improve the portability and to reduce the total size of the antenna. The measured return loss of the proposed TEM horn with the broadband balun is less than -10 dB(VSWR<2) from 2 GHz to 10 GHz. Compared to a conventional triangular type TEM horn, the proposed antenna shows about 80 % reduced volume and gives the broadside gain about 12 dBi with a gain deviation less than 6 dB from 2 GHz to 10 GHz. The time domain measurement shows less than 0.4 ns group delay and the pulse measurement using the transmitting signal with the rising time of 58.5 ps shows the received pulse with the rising time of 66.5 ps, which is less than 10 % rising time variation.

• Plant Journal
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• v.18 no.3
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• pp.28-40
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• 2022

As the proportion of renewable energy generation is expected to increase, public power generation businesses need to actively consider implementing the expansion of biomass mixing, In this study, the biomass co-firing rate is being changed from 0wt.% to 5.0wt.% at 500MW coal-fired power plant, measuring the major operation characteristics of the pulverizer. First, the composition analysis and grinding characteristics of lignocelluosic biomass were examined, and the effect of volume increase on dirrerential bowl pressure difference, motor current, coal spillage, outlet temperature, and internal fire count was analyzed. As the co-firing rate increased, it was confirmed that the difference in the differential bowl pressure, motor current, and coal spillage treated increased, and the outlet temperature was minimal. The number of internal fires is difficult to find a clear correlation, but it has been confirmed that it is highly likely to occur in combination with other driving factors.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.29-34
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• 2009

Recently, we have a lot interest in a sudden rise of oil prices and a change weather for the earth warmming, so, development of new alternative fuels need in order to spare fossil fuel and reduce exhaust emissions for air pollution prevention. Biodiesel, which can be generated from natural renewable sources such as new or used vegetable oils or animal fats, may be used as fuel in diesel engine of compression ignition engine. In this paper, the combustion characteristics between neat diesel oil and biodiesel blends(10 vol.% biodiesel and 20 vol.% biodiesel) were tested using four stroke, direct injection diesel engine, especially this biodiesel was produced from soybean oil at our laboratory. This analysis showed that cylinder pressures, the rate of pressure rises and the rate of heat releases were decreased as the blending ratios of biodiesel to diesel oil increased because of lower heating value of biodiesel in spite of increased oxygen content in biodiesel.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2008.12a
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• pp.133-138
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• 2008

1) 두과작물의 생초수량과 건물수량은 작물별로 차이가 컸다. 지상부는 Red clover가 생초수량 38.6 ton/ha, 건물수량 7.86 ton/ha로 가장 많았으며, 지하부 또한 Red clover가 생초수량 30 ton/ha, 건물수량 6.2 ton/ha로 가장 많았다. 2) CP 수량 및 TDN 수량은 Red clover가 각각 1 ton/ha, 4.6 ton/ha로 유의하게 높았으며 NDF와 ADF는 수확시기가 늦을수록 높은 경향을 나타내서 Galega와 Cicer milk vetch가 가장 높았다. 또한 상대사료가치(RFV)는 공시품종 대부분이 100 이상을 나타내어 사료가치가 우수하였으며 Yellow blossom sweet clover, Crimson clover, Hairy vetch 등은 151% 이상으로 1등급에 속하였다. 3) 가축사육능력은 $K_{cp}$(2.18 head/ha/yr) > $K_{TDN}$(1.25 head/ha/yr) >K(0.04 head/ha/yr) 순으로 높게 나타났으나 이는 상당히 낮은 수준이었으며 이는 두과작물의 적은 수량으로 인한 결과라 판단되어진다. 4) 두과작물과 화본과작물 혼파시 $K_{cp}$ $K_{TDN}$ 모두 두과작물 평균 2.18, 1.25보다 높았다. 또한 Rye-Galega 8:2 비율, Rye-Winter pea 7:3 비율에서 건물수량, $K_{cp}$ $K_{TDN}$이 화본과 단파시보다 증가하여 혼파효과가 인정되었다. 특히 건물수량과 $K_{TDN}$ 관계에서 혼파 비율에 따라 건물수량에 큰 차이를 보이지 않은 반면 $K_{TDN}$은 모든 비율에서 증가하여 사료가치가 상승하였다.

• Korea journal of population studies
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• v.29 no.1
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• pp.25-56
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• 2006

This study attempts to review the increasing trend in international marriage of Koreans since 1990 and explore the pattern of socio-demographic characteristics of the married couples. This paper develops a conceptual scheme for changing pattern of nuptiality including an increase in international marriage. As the key forces behind the recent increase in international marriage of Koreans, the effects of rapid decline in fertility, rise in sex ratio at birth, urbanward migration of young women, expansion of gender-equity norms, and globalization are stressed. Micro-data from the marriage registration for the period $1990{\sim}2004$ and the divorce registration for the period $2000{\sim}2004$ are utilized. This study focuses on analyzing age at marriage, previous marital experience, education, occupation, and residence of the married couples. Attention is also focused on demographic characteristics of the divorced couples. Results of analyses reveal that there exists a great deal of diversity in international marriage of Koreans. A notable aspect is the profound differences between Korean men and women in the characteristics of their foreign spouses and themselves as well. Another prominent factor emphasized in the analysis is the nationality of foreign spouse. It is indicated that the stereotype of international marriage facilitated by marriage squeeze can be mainly applied to marriages between Korean men and foreign wives from China, southeast Asian countries and the CIS of the old Soviet Union. On the other hand, direct effects of value transformation and globalization are emphasized in the explanation of marriages between Korean men and foreign wives from more developed countries as well as marriages between Korean women and foreign husbands.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.60-67
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• 2010

Korea's large-scale incinerating facilities of domestic waste were built in the late 1980's. It was found that most of the incinerators were designed during the period and even the ones constructed afterwards have been built without any changes or modifications. However, the nature of waste fed into incinerators is undergoing a radical change due to government policies on waste collection, which is upheld by a research into changes in the heating value of domestic wastes. As a result, refractories and stokers are being damaged in many of the facilities due to overheating. On the other hand, the formation of clinkers on boilers' heating surface, which curbs he at transfer, results in problems such as a fall in used heating value and a rise in the temperature of combustion chambers. Methods are being deployed to resolve the problems-such as spraying water on piles of waste, incinerating food waste by mixing together what has been separately collected, spraying water on combustion chambers, etc. Such actions are not a fundamental solution, nor redesigning and rebuilding incineration facilities is cost-effective. This research seeks to develop a fundamental solution to address the situation.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.90-104
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• 2020

The current global economy is changing from a proprietary commercial economy to a shared economy of value sharing. In modern society, single-person households have become common type of households. The reason for the increase in single-person households is due to the rising age of first marriage, the increasing number of elderly people, which is a result of the extension of the average life expectancy, fewer marriages, more divorces, goose fathers, the separation between dwellings for work, etc. Especially a significant amount of single-person households is occupied by young people, which is common in large cities. Along with the increase in the number of single-person households, the youth has created a new demand for housing demand for single-person households. The purpose of this study is to identify which factors influence the preference of a share house as an alternative to a single-person household by making an empirical analysis. As a result of the analysis, the accessibility of a share house, the characteristics of the building and the facilities all had a significant effect on the preference.

• Survey Research
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• v.3 no.1
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• pp.65-90
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• 2002

The purpose of this study is to develope an appropriate method of the household projection in Korea. Given the data constraints, the headship rate method is selected. This method is known to be responsive to changes in demographic factors related to household formation. To project future headship rates, the method of net transition rates based on the average of two-census intervals was adopted for household heads ages 35 and over, while the log-linear formula was employed for those aged under 35. The future headship rate of Korean males shows a one-peak pattern with plateau, whereas that of Korean females marks a two-peak pattern. For a better projection of household in the future, one-person households should be treated more carefully, because they are mostly either young adults or the elderly whose activities of household formation and dissolution are very hard to forecast.