• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.52-55
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• 2005

An experiment was conducted to evaluate the efficacy of continuous lateral shoot pinching and gradual adjustment of drip irrigation lines in improving plant health as well as fruit yield and quality in white-spined cucumber grown in the greenhouse. Grafted white-spined cucumber seedlings were established at a density of 18,000 plants per ha in a greenhouse. Main stems were pinched at 21st node. Each of the lateral shoots was pinched at the 3rd node and 2-3 fruits per lateral shoot were harvested. Drip irrigation lines were gradually adjusted to provide water to the area of maximum root concentration. Plants grown with these combined treatments produced $55\%$ more lateral shoots and 38% more marketable yield, as compared to the control.

• Journal of Korean Society of Transportation
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• v.20 no.6
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• pp.45-56
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• 2002

In this research we estimated regional gross fixed capital stock of transport sector, such as road railroad, airport and seaport during 1968-1997 in Korea. We also compared our estimation results with those of Korea and Japan. As basic analytic method, we used the regional allocation method. To estimate regional gross fixed capital stock of transport sector, we used the basic data on national wealth surveys in 1997, regional land price index and regional facilities index in transport sectors. We used the most reasonable data in the process of estimation after reviewing the collected data In order to get the reasonable capital stock by regions. we chose the allocation index which can minimize the difference between the estimated result and the real regional capital stock in the process to allocate the total gross capital into the regions. Compared our results with those of other researches in Korea, estimates in our research project could be said more accurate than those.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.41-47
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• 2010

Purpose: The purpose of this study was to compare the functional abilities of the low bulb obturators with those of high bulb obturators in terms of patients' evaluation. Material and methods: This study included 11 maxillectomy patients who underwent postoperative prosthodontic rehabilitations. Two obturators of the same design except for different bulb heights, were fabricated for each of the maxillectomy patient. After two months of alternate use, the functions of the obturators were measured by investigating the patients' subjective evaluations in terms of convenience, speech, nasality, leakage, and mastication and identifying their preferred prostheses. Wilcoxon signed rank test was used as a statistical method (P < .05). Results: There were no significant differences in patient evaluations of low and high bulb obturators (P >.05). And patients' preferences varied. Conclusion: In extreme situation such as in mouth opening limitation, the use of low bulb obturators can be recommended and result in comparable speech function to that of obturators with high lateral walls.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.565-567
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• 2000

필기 한글 인식에서 원래 패턴의 모양을 유지하는 골격선 추출은 중요하다. 세선화에 의존하는 기존 방법은 작은 잡음에 민감하다는 단점을 안고 있다. 본 논문은 필기 한글 패턴에 적합한 새로운 골격선 추출 방법을 제안한다. 먼저 한글 패턴은 T-접점과 B-접점이라는 두가지 모양 특징을 중심으로 분할할 수 있다는 관찰에 근거하여 유사블록으로 이루어진 부품 집합으로 분할한다. 또한 세 개 이상의 획이 복잡한 형태로 만나는 지점을 결합 부품으로 분할한다. 그런 다음, 각 부품에서 접점의 형태에 따라 결합 부품을 추가 탐지한다. 결합 부품과 인접한 부품들의 연관 관계에 따라 골격선을 구하고, 골격선의 연결성을 보장하기 위해서 선분 연장을 수행한다. 본 논문에서 기존의 방법과의 비교를 위해 다섯 가지 비교 기준을 설정하고, 이를 기반으로 비교 분석하였다. 본 논문에서 제안한 방법이 여러 기준에서 세선화-기반 방법보다 우수함을 보였다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.677-680
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• 2006

이 논문은 무선 센서 네트워크에서 최소 파워 구성 방법을 이용하여 에너지를 효율적으로 사용하면서 네트워크의 수명을 늘리고 지연(delay)을 줄이는 방안을 제시한다. 지금까지 에너지를 효율적으로 사용하기 위해 topology control, power-aware routing, sleep management 방법을 각각 독립적으로 연구되었는데 최소파워 구성은 위의 3가지 방법을 통합 최적화하여 에너지 효율적 사용 문제에 접근한다. 이러한 최소파워 구성 방법을 이용하여 선택적 웨이트 컨트롤(Selective weight control) 알고리즘을 제안하여 네트워크 전체 수명을 연장시키고 지연을 줄일 수 있다. 이 알고리즘은 각 노드가 주기적으로 잔류에너지를 인접노드들과 공유하여 에너지 랭크(rank)값을 유지한 상태에서 최소 에너지 경로를 사용하면서 에너지가 주위 노드들보다 작아질 때는 에너지가 많은 노드가 경로에 포함이 되도록 하여 특정 노드가 에너지 고갈되지 않고 네트워크내의 각 노드가 고르게 에너지를 소모하게 한다.

• Food Science and Preservation
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• v.8 no.1
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• pp.23-29
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• 2001

To extend the freshness of late autumn Chinese cabbage, the packaging and loading effects on the quality were investigated during cold storage. Judging from overall quality during storage period, late autumn Chinese cabbage could be stored by 3 months at 0$\^{C}$ cold storage. However, late autumn Chinese cabbage was not acceptable for long-term storage because of its marketability and the storage cost. Among 3 packaging methods(PP-net, carton and plastic container) for stored Chinese cabbage, plastic container and carton were more effective than PP-net packaging for the freshness prolongation. Gas composition in the plastic bags during storage was not significantly different among packaging conditions and O$_2$ and CO$_2$ concentrations were 13∼18% and 0.75∼7.48%, respectively, MAP with plastic film was effective for the quality retention because of low oxygen composition and high humidity condition in the bags.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.6
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• pp.21-27
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• 2009

As portable electronic systems being used more often, it becomes a more important issue to lengthen the lifetime of the power battery of the system, for instance, by developing batteries of a higher efficiency. A simple as well as practical method to lengthen the lifetime is to use multiple batteries that are connected in parallel. But in this paper we present a new idea in using multiple batteries, with which the residual energy of the battery can be used in the sense of recycling. The idea is based on a usual phenomenon that a battery cell that has been used until its voltage has dropped below a reference level may still have some residual energy, due to which the voltage can recover when the cell takes a rest for a while. As a practical realization scheme of this idea, a multi-cell configuration method with a cell selection switch is introduced, and its feasibility has been examined by performing experimental observations on the behavior of battery discharge. It has been found that the lifetime of an Alkaline primary battery cell can be lengthened approximately by one or two hours with the proposed method.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2006.09a
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• pp.59-79
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• 2006

The successful execution of shield tunnelling depends on the cutting ability of cutter. So the selection of shape, size and material of cutter according to geology condition is important work. Since shield tunnelling method was first invented in 1881, the cutting tool for rock has been developed owing to various experiments and researches, the study for soil, however, is insufficient. This paper introduces the shield tunnelling that will be carried out on weathered rock section (920m) of Seoul Subway Line 7 Extension C703. The shape and the material of cutter are discussed required for execution without replacement of cutter tool as well as for advance of excavation efficiency. In addition the estimation method of cutter abrasion in case of excavation on weathered soil is proposed and verified. Specially, the coefficient of abrasion for different soil and cutter is proposed by means of investigation into construction example of foreign country.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.3
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• pp.153-159
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• 2018

Many researches have been carried out on carbonation, a representative deterioration in underground structure. The carbonation of RC (Reinforced Concrete) structure can cause steel corrosion through pH drop in concrete pore water. However extension of service life in RC structures can be obtained through simple surface protection. Unlike the conventional deterministic maintenance technique, probabilistic technique can consider a variation of service life but it deals with only normal distributions. In the work, life time-probability distributions considering not only normal but also log distributions are induced, and repair cost estimation technique is proposed based on the induced model. The proposed technique can evaluate the repair cost through probabilistic manner regardless of normal or log distribution from initial service life and extended service life with repair. When the extended service life through repair has log distribution, repair cost is effectively reduced. The more reasonable maintenance strategy can be set up though actual determination of life-probability distribution based on long term tests and field investigations.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.83-92
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• 2005

We try to evaluate the stock level of Korean transportation infrastructure comparing Korean SOC stock level with those of OECD countries. In order to do so, we work on indices to show the transportation infrastructure stock levels of various countries. Among several indices, we select the effective road-extension rate per population density and the effective railroad-extension rate per population density corresponding to road and railroad. We compare Korean road and railroad stock levels with those of OECD countries, to make use of the effective road-extension rate per population density and effective railroad-extension rate per population density. We choose the Britain, Greece, Portugal, and Sweden to compare Korea because their sizes of population and territory are similar to those of Korea. Using International comparison, we arrive at the conclusion that Korean road and railroad stock levels are 63.4% and 53.2% of those of four countries respectively. In addition, we estimate the target level of road and railroad stocks and compute the target level of investments in road and railroad based on the result.