• Transactions on Electrical and Electronic Materials
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• 제8권2호
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• pp.53-57
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• 2007

In this study, a novel slurry containing ceria as the abrasive particles was analyzed in terms of its frictional, thermal and kinetic attributes for interlayer dielectric (ILD) CMP application. The novel slurry was used to polish 200-mm blanket ILD wafers on an $IC1000_{TM}$ K-groove pad with in-situ conditioning. Polishing pressures ranged from 1 to 5 PSI and the sliding velocity ranged from 0.5 to 1.5 m/s. Shear force and pad temperature were measured in real time during the polishing process. The frictional analysis indicated that boundary lubrication was the dominant tribological mechanism. The measured average pad leading edge temperature increased from 26.4 to $38.4\;^{\circ}C$ with the increase in polishing power. The ILD removal rate also increased with the polishing power, ranging from 400 to 4000 A/min. The ILD removal rate deviated from Prestonian behavior at the highest $p{\times}V$ polishing condition and exhibited a strong correlation with the measured average pad leading edge temperature. A modified two-step Langmuir-Hinshelwood kinetic model was used to simulate the ILD removal rate. In this model, transient flash heating temperature is assumed to dominate the chemical reaction temperature. The model successfully captured the variable removal rate behavior at the highest $p{\times}V$ polishing condition and indicates that the polishing process was mechanical limited in the low $p{\times}V$ polishing region and became chemically and mechanically balanced with increasing polishing power.

• 한국전산구조공학회논문집
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• 제27권4호
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• pp.321-328
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• 2014

도시방재업무의 기본은 대상지역의 지형과 지물(시설물)에 대한 상호적 이해와 그에 관한 정보관리로부터 시작된다. 도시방재업무를 보다 효율적으로 수행하기 위해서는 관련 정보를 모두 수용할 수 있는 일관된 프레임 하에서 데이터를 수집하고, 모델을 생성하며, 정보를 축적하고 관리할 수 있어야 한다. 본 연구에서는 도시 객체를 대상으로 표준화된 도시정보모델을 생성하는 방법 및 정보관리의 관점에서 도시모델을 방재업무에 효과적으로 활용할 수 있는 방안을 제시하였다. 이를 위해 방재모형 생성에 필요한 도기 객체를 분류하고, 객체별 필요속성을 도출하는 과정을 거쳐, 방재정보를 포함한 관련 정보를 효율적으로 관리할 수 있는 통합 데이터 스키마인 CityGML기반의 개방형 도시정보모델의 생성 방안을 제시하였다. 또한 예제모델의 구현과 검토를 통해 제시된 도시정보모델 구축 방법론의 방재업무 적용성과 활용성을 확인하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.142-142
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• 2023

Humans inevitably and continuously produce wastewater in daily life worldwide. To decrease the degradation of river water bodies and aquatic ecosystem therein, humans have built systems at different scales to collect, drain, and treat household-produced wastewater. Particularly, municipal wastewater treatment plants (WWTPs) with centralized controls have played a key role in reducing loads of nutrients in domestic wastewater for the last few decades. Notwithstanding such contributions, impaired rivers regarding water quality and habitat integrity still exist at the whole river basin scale. It is highly attributable to the absence of dilution capacity of receiving streams and/or the accumulation of the pollutant loads along flow paths. To improve the perspective for individual WWTPs assessment, the first crucial step is to achieve systematic understanding on spatial distribution characteristics of all WWTPs together in a given river basin. By taking the initiative, our former study showed spatial hierarchical distributions of WWTPs in three large urbanized river basins in Germany. In this study, we uncover how municipal WWTPs in the contiguous United States are distributed along river networks in a give river basin. The extended spatial scope allows to deal with wide ranges in geomorphological attributes, hydro-climatic conditions, and socio-economic status. Furthermore, we identify the relation of the findings with multiple factors related to human activities, such as the spatial distribution of human settlements, the degree of economy development, and the fraction of communities served by WWTPs. Generalizable patterns found in this study are expected to contribute to establishing viable management plans for recent water-environmental challenges caused by WWTP-discharges to river water bodies.

• 한국산림과학회지
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• 제99권5호
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• pp.736-743
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• 2010

This study examined the ecological attributes of classified forest community by cluster analysis in the mixed forest of Mt. Seokbyung Experimental Forest of Gangwon-Do. The vegetation data were collected in randomly established 51 sample plots (2.04 ha) and analysis adopted the cluster analysis, importance value index, and Shannon's diversity index. Main results were as follows; 1) the study area was classified into 4 clusters (A, B, C and D). 2) The cluster A was dominated by Pinus densiflora with an importance value of 71.6%. The most dominant species in the cluster B and cluster C were Larix leptolepis (57.1%) and Quercus mongolica (40.2%), respectively. Finally, The cluster D was dominated by P. densiflora (30.6%) and Q. mongolica (31.0%) with the mixed forest. 3) In the P. densiflora community (cluster A), distribution of DBH class showed a reverse J-shaped curve. In the L. leptolepis community (cluster B), individuals of dominant species had the bell-shaped distribution. Oak species indicated uniform distribution of DBH class (under 25 cm) in the mixed P. densiflora - Q. mongolica community (cluster D). 4) The species diversity index of the communities in descending order were: Pinus densiflora - Q. mongolica community > Larix leptolepis community > Pinus densiflora community > Quercus mongolica community.

• 농업과학연구
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• 제39권3호
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• pp.319-325
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• 2012

This study investigated the user's attitude to the nature trail called Gubulgil in Gunsan reservoir area and evaluated the quality of user's satisfaction of the trails and their facilities by importance-performance analysis (IPA). User's evaluation was achieved through questionnaire survey and total 283 pieces of subjects were used for the analysis. The results are as follows. Firstly, importance value of circularity of trails was very high, and it has great implication to ordinary trails which connect ecological, historical and cultural spots routinely and linearly. Secondly, through the IPA, relatively dissatisfied attributes were parking lots, direction boards, storytelling, convenient facilities and encountering of wildlife. Expansion of parking lots can cause the environmental disruption, so running a shuttle service from Gunsan downtown to the reservoir at weekends can be more reasonable. In case of ecological and historical information delivery, softwares like storytelling contents with sense of realism as well as hardwares of informative signboards are very important in nature trails. Encountering wildlife in trails is fascinating experience but it means visitors may disturb wildlife habitats. So route design should be done very carefully not to intrude their territories.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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• pp.253-260
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• 1999

The recycling cell formation problem means that disposal products me classified into recycling part families using group technology in their end of life phase. Disposal products have the uncertainties of product status by usage influences during product use phase and recycling cells are formed design, process and usage attributes. In order to treat the uncertainties, fuzzy set theory and fuzzy logic-based neural network model are applied to recycling cell formation problem far disposal products. In this paper, a heuristic approach fuzzy ART neural network is suggested. The modified fuzzy ART neural network is shown that it has a great efficiency and give an extension for systematically generating alternative solutions in the recycling cell formation problem. We present the results of this approach applied to disposal refrigerators and the comparison of performances between other algorithms. This paper introduced a procedure which integrates economic and environmental factors into the disassembly of disposal products for recycling in recycling cells. A qualitative method of disassembly analysis is developed and its ai is to improve the efficiency of the disassembly and to generated an optimal disassembly which maximize profits and minimize environmental impact. Three criteria established to reduce the search space and facilitate recycling opportunities.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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• pp.253-260
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• 1999

The recycling cell formation problem means that disposal products are classified into recycling part families using group technology in their end of life phase. Disposal products have the uncertainties of product status by usage influences during product use phase and recycling cells are formed design, process and usage attributes. In order to treat the uncertainties, fuzzy set theory and fuzzy logic-based neural network model are applied to recycling cell formation problem for disposal products. In this paper, a heuristic approach for fuzzy ART neural network is suggested. The modified Fuzzy ART neural network is shown that it has a great efficiency and give an extension for systematically generating alternative solutions in the recycling cell formation problem. We present the results of this approach applied to disposal refrigerators and the comparison of performances between other algorithms. This paper introduced a procedure which integrates economic and environmental factors into the disassembly of disposal products for recycling in recycling cells. A qualitative method of disassembly analysis is developed and its aim is to improve the efficiency of the disassembly and to generated an optimal disassembly which maximize profits and minimize environmental impact. Three criteria established to reduce the search space and facilitate recycling opportunities.

• 한국군사과학기술학회지
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• 제14권5호
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• pp.913-919
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• 2011

In this paper, we present a new efficient event detection algorithm for sensor networks with faults. We focus on multi-attributed events, which are sets of data points that correspond to interesting or unusual patterns in the underlying phenomenon that the network monitors. Conventional algorithms cannot detect some events because they treat only their own sensor readings which can be affected easily by environmental or physical problem. Our approach exploits spatio-temporal correlation of sensor readings. Sensor nodes exchange a fault-tolerant code encoded their own readings with neighbors, organize virtual sensor readings which have spatio-temporal correlation, and determine a result for multi-attributed events from them. In the result, our proposed algorithm provides improvement of detecting multi-attributed events and reduces the number of false-negatives due to negative environmental effects.

• 한국농공학회논문집
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• 제48권7호
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• pp.17-22
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• 2006

Potential application topics of KOMPSAT-3 image in the field of precision agriculture are suggested. The topics can be categorized as fundamental and applied ones that have contents of static and dynamic characteristics respectively. As fundamental topics, precision information of agriculture that is related to farmland and its crop attributes, precision information of rural infrastructure that is related to rural village and its facilities, precision information of stream environment that is related to rural water resources and its facilities, and precision information of eco-environment that is especially related to riparian ecology and environmental status are included. As applied topics, precision rural water resources that has thematic contents of continuous and event-based runoff, spatial and temporal soil moisture and evapotranspiration, precision agricultural watershed environment that has the contents of spatial and temporal soil loss, sediment and pollutants transport, and precision temporal and spatial crop growth that has the contents of temporal crop texture, spectral reflectance, leaf area index, spatial crop protein information.

• 한국환경과학회지
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• 제25권4호
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• pp.543-556
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• 2016

Sangju, a city in the North Gyeongsang Province, is well known as "Three Whites", representing its three main agricultural products: rice, silkworm, and dried persimmons. Therefore, development of a variety of dishes or products that can promote the consumption of dried persimmons is an urgent requirement for this region. This study was designed to provide fundamental information for revitalizing community-based specialized agriculture through scientific inquiry into medicinal foods and to develop a medicinal food menu based on the results of previous research and pre-survey. The pre-survey results and incompatibility revealed that palatability influenced people's decision to consume dried persimmons far more than pharmacological functionality. Therefore, palatability played an important part in the development of dried persimmon puddings with acceptable texture. These dishes are in high demand as they suit the tastes of variety of consumers. The inclusion of various additives lowered the sugar content in the developed foods and made the products alkalescent (pH > 7), thereby improving functionality. Unique color and flavor additives were also important criteria that determined the selection attributes of the developed medicinal foods. In addition, the additives had a positive effect on the fragrance and texture of the foods. In conclusion, the results suggested that use of additives provides significant advantages in promoting the consumption of Sangju-dried persimmons by improving both functionality and palatability.