• Journal of Families and Better Life
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• v.22 no.4
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• pp.95-104
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• 2004

• KOREAN POULTRY JOURNAL
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• v.19 no.2 s.208
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• pp.34-39
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• 1987

식생활변화의 원인을 알아보기 위해서는 식생활의 패턴이 어떻게 형성되는지 살펴볼 필요가 있다. 한번 형성된 식생활패턴은 쉽게 변하지 않는다. 변하려면 여러세대가 걸린다.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.21-34
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• 1997

Retention ponds have been dug along some of the motorways in France to minimize environmental pollution by preventing pollutants from spreading over the surrounding area. A series of studies have been conducted to determine the physicochemical characteristics of the particles settling down in such a pond to evaluate the effectiveness of the pond as a trap for heavy metals such as Pb, Zn and Cd. The highly contaminated roadside soil and the uncontaminated background soil were also studied for comparison. The settling particles exhibited heavy metal concentrations of 2 to 8 times as much as the background Sologne soil, depending on the metal species. However, the heavy metal concentrations in the roadside soil were 7 to 26 times higher than those in the· settling particles. Sequential extraction experiments illustrated that the highly contaminated roadside soil consisted mainly of the readily soluble fractions (FII, FIII and FIV) for all three heavy metals, but little W which is hardly soluble. The proportion of W considerably increased up to one third of the total in the settling particles for Pb and Zn. This result as well as the large concentration differences between the roadside soil and the settling particles indicates that most of the heavy metals were lost to the surroundings even before reaching the retention pond. Cd exhibited somewhat different behavior in that the most soluble FI, which is negligible for Pb and Zn, occupied as much as one fourth of the total in the roadside soil. In addition, FV for Cd did not increase in the settling particles.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.587-599
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• 2011

The purpose of this study was to analyze variable-controlling strategy (below vcs) and the ability to infer the effect of variables in Middle school students who experienced 'Thinking Science' activities in a CASE program. For this study, 71 9th grade students experienced in CASE program for 2 years were selected as the experimental group and 72 students were selected as the control group. All students were tested with Science Reasoning TaskVII. The five types of variable-controlling strategy were extracted from students' response. According to the result of this study, the students experienced in CASE program was more successful in the variable-controlling strategy of length, quality, and shape than the control group. The types of reasoning ability of the variable effect intuitively were categorized as possibility of reasoning, impossibility of reasoning, and impossibility of reversible thinking. It has shown that the reasoning ability of the experimental group was higher than that of the control group in the length and thickness variable effect. The results of this study implied that the variable controlling activities in CASE program could be effective for learning variable controlling, and eventually, for the development of reasoning ability of the variable controlling effect. In the ability to infer the effects of variables to get difficult Intuitively, both groups were similar to the rate of cognitive level reached to the formal operation in generalization, and the student of experimental group was 1.5 times faster than the control group.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.5
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• pp.56-65
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• 2009

Stereoscopic images consist of the left image and the right image. Thus, stereoscopic images have much amounts of data than single image. Then an efficient image compression technique is needed, the DPCM-based predicted coding compression technique is used in most video coding standards. Motion and disparity estimation are needed to realize the predicted coding compression technique. Their performing algorithm is block matching algorithm used in most video coding standards. Full search algorithm is a base algorithm of block matching algorithm which finds an optimal block to compare the base block with every other block in the search area. This algorithm presents the best efficiency for finding optimal blocks, but it has very large computational loads. In this paper, we have proposed fast disparity estimation algorithm using motion and disparity vector information of the prior frame in stereo image coding. We can realize fast disparity vector estimation in order to reduce search area by taking advantage of global disparity vector and to decrease computational loads by limiting search points using motion vectors and disparity vectors of prior frame. Experimental results show that the proposed algorithm has better performance in the simple image sequence than complex image sequence. We conclude that the fast disparity vector estimation is possible in simple image sequences by reducing computational complexities.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.405-414
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• 2021

Purpose. This study was conducted to evaluate clinical usefulness by evaluating the marginal bone resorption and survival rate of an implant with a taper straight type SLA surface domestically available on the market recently. Materials and methods. 40 implants satisfying the including criteria were observed for one year of 125 implants of 83 adult men and women who had KISPLANT^® implanted from August 2016 to December 2019 at the Department of Periodontology, Chonnam National University Dental Hospital. The marginal bone level was measured on periapical radiographs taken initially and 1 year later and we analyzed implant survival and success rates. A t-test was used for the analysis of the association between the marginal bone resorption and the severity of periodontitis, supportive periodontal therapy, the inserted site, the cause of extraction, immediate placement, and systemic disease. Results. After 1 year of loading, the mesial bone resorption was 0.74 ± 1.07 mm, and the distal bone resorption was 0.53 ± 1.04 mm. The marginal bone resorption of 2 mm or more occurred at 3 implants out of 40 implants after 1 year, so the success rate of implant was 92.5% and survival rate was 100%. There was a significant difference in mesial marginal bone resorption according to the inserted site and no significant differences were found between marginal bone resorption and the other factors. Conclusion. As a result of marginal bone resorption, success rate, and survival rate in this study, we found little marginal bone resorption and high survival and success rate. It can be concluded that they represent excellent clinical results.

• KDI Journal of Economic Policy
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• v.22 no.1_2
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• pp.193-283
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• 2000

외환위기 이후 재정적자가 급격히 확대되면서 재정적자에 대한 일반인들의 관심이 높아지고 있다. 그러나 재정적자가 거시경제에 구체적으로 어떤 영향을 미치는가에 대한 실증분석은 많지 않은 편이다. 본고는 재정적자가 민간저축률과 물가상승률에 미치는 영향을 살펴보고 있다. 본 논문의 결과를 요약하면 다음과 같다. 첫째, 저축률과 재정적자 사이에는 리카도 동등가설이 예측하는 것과 같은 관계가 표면적으로 발견된다. 즉, 재정지출이 변하지 않을 때 재정적자의 증가는 민간저축률을 증가시켜 국민경제 전체의 저축률은 크게 변하지 않는다. 둘째, 재정수지가 변하지 않더라도 재정지출의 증가는 민간저축을 감소시킨다. 그리고 재정수지가 변하든 변하지 않든 정부소비나 이전지출의 증가는 국민저축률을 감소시킨다. 셋째, 재정적자는 물가에 별 영향을 주지 않는다. 이 가운데 첫째와 셋째의 결과는 별로 새삼스러운 것이 되지 못한다. 그러나 둘째의 결과는 지금까지 논의되지 않았던 사실을 알려주고 있다. 특히 1980년대 말 이후 GDP 대비 재정규모가 추세적으로 증가하고 있으며, 최근의 외환위기 이후에는 금융구조조정 지원 등에 따라 재정규모가 급격히 증가하고 있고, 장기적으로는 국민연금급여 등 사회보장지출의 증가가 예상됨을 고려할 때, 재정규모 증가를 억제하는 일에 보다 적극적인 노력을 기울일 필요가 있음을 알게 된다. 한편 본고에서의 한국은행의 준(準)재정활동을 고려하지 않았으나, 이를 고려할 때에도 재정수지가 물가상승률에 별다른 영향을 미치지 않는지에 대한 추가적 연구가 필요하다고 판단된다.

• The Journal of the Acoustical Society of Korea
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• v.18 no.1
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• pp.32-37
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• 1999

Rail noise and vibration is one of the major problem for the residents living nearby railway tracks. The rail noise may inflict a considerable damage to physiological, spiritual, mental and discomfort to neighboring peoples. Therefore, residents living nearby railway were appeal many troubles. Nevertheless, in our country, adequate guidelines for the rail noise are not yet established because of the lack of basic data and insufficient research works. In this point, this study attempts to surveys the influence of rail noise in urban area using questionnaire. This study also present a basic data in establishing effective plans for rail noise in the future.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.5
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• pp.541-546
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• 2008

A novel, simple and broadband $90^{\circ}$ phase shifter was proposed and fabricated by the LTCC process. It is composed of a $180^{\circ}$ transmission line between two $90^{\circ}$ shorted transmission lines. Design equations for the proposed $90^{\circ}$ phase shifter are derived by the method of admittance parameter analysis. Based on design equations, $90^{\circ}$ phase shifter was designed and fabricated to operate in the C-band with ${\pm}2^{\circ}$ of phase deviation.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.53-54
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• 2015

기존의 IEC 61850 표준 적용 국내 디지털변전소는 Station 레벨에 한정되어 구축되어 왔다. 향후 구축될 Process 레벨을 포함한 풀(Full) 디지털 변전소 디지털화는 디지털변전소 운전에 있어 중요하고 긴급한 신호인 Process bus를 통한 SV와 GOOSE신호의 전송으로 이루어지고 있다. Process bus를 활용한 배전선로 보호용 통합 IED는 GIS 등 변전소 전력설비로부터 전압과 전류 값을 MU(Merging Unit)를 통해 공급받아 각 구간의 Bay 혹은 Bank단위로 통합적인 보호 기능을 수행하고, 주 IED와 예비 IED가 서로의 상태를 상호 감시하여 보호기능의 이중화를 이루어야 하고, Sampled Value를 처리하기 위한 정밀한 시각동기화 기능을 갖추어야 한다. 만약, Process bus 시스템의 문제로 인해, 지연과 손실이 발생한다면 변전소 보호 제어에 영향을 줄 수 있으므로 Process bus를 디지털변전소에 적용하기 위해서는 Process bus 기반의 네트워크시스템에 연결된 MU와 IED가 송수신하는 SV와 GOOSE를 손실과 지연없이 전송할 수 있는지를 분석해야 한다. 본 연구에서는 디지털변전소 네트워크 시뮬레이션 시험을 통해, 배전선로용 통합 IED의 성능검증을 위해 Process bus 네트워크 시스템을 설계하고 시뮬레이션 시험을 수행하여 이를 통해 향후 국내의 Process bus 디지털변전시스템 구축을 위한 효과적인 네트워크 시스템 설계방법을 제시하고자 한다.