• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.535-539
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• 2009

Evapotranspiration (ET) is one of the main factor to understand the hydrologic cycle on land surfaces of entire globe. It accounts for about 65% of precipitation returning to the atmosphere. Accurate estimation of the ET is essential to many applications of water resources management, hydrology, meteorology, climatology, and agriculture. Over the past few decades, there have been extensive efforts to develop and validate a number of ET models. Priestley-Taylor (P-T) and Food and Agriculture Organization Penman-Monteith (P-M) models are generally recognized as simple, but great operational approaches to estimate ET over different land cover types. In this study, we compare/validate different models of increasing complexity, P-T, P-M, and Common Land Model (CLM) in croplands, IA.

• 품질경영학회지
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• 제41권4호
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• pp.673-681
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• 2013

Purpose: The purpose of this study is to investigate the design optimization modeling of screening procedures based on the assessment of misclassification errors. Methods: Misclassification errors due to measurement variability are derived for normally distributed quality characteristics. Further, an optimization model for ensuring the level of outgoing quality is proposed and demonstrated through an illustrative example. Results: It is shown that two types of misclassification errors (i.e., false acceptance and false rejection) may be properly compromised through an analytical assessment of measurement errors and an optimization modeling. It is also discussed that a variety of optimization modeling may be enabled based on the derivation of measurement errors. Conclusion: It may be concluded that the design of screening inspection may further be facilitated by including the effect of measurement errors on the performance of screening inspection procedure.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.467-470
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• 2009

Variable loads along the drive-train are attributed to frequent failures of gears, bearings, and other components. Wind parameters cannot be controlled and therefore any turbine load-reducing remedies must be established based on proper insights into the wind-turbine interactions. A novel control concept to performance optimization of wind turbines is presented. This proposed concept is based on analysis of the turbine status reflected in the SCADA data. Modern computational techniques are used to optimize performance of a wind turbine from tree basic perspectives: drive-train, power output, and power quality. The proposed approach demonstrates that gains in the metrics representing the three perspectives and the corresponding control goals can be significantly improved for any wind turbine. The solution is applicable different turbine types operating in different wind regimes, e.g., winds of different speeds and variability. Simple and transparent parameters allow an operator to determine a balance between the operations and maintenance, technical, business objectives. The proposed modeling framework was embedded in software. The software tool has been tested on the data collected from 1.5 MW wind turbines.

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.23-38
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• 1999

This study addresses the reference spent fuel and its characteristics for developing a geological repository concept. As a disposal capacity of the reference repository system to be developed, spent fuel inventories were projected based on the basis of the Nuclear Energy Plan of the Long-term National Power Program. The reference spent fuel encompassing a variability in characteristics of all existing and future spent fuels of interest was defined. Key parameters in the reference fuel screening processes were the nuclear and mechanical design parameters and the burnup histories for existing spent fuels as of 1996 and for future spent fuels with the more extended burnup the initial enrichment and its expected turnup. The selected reference fuel was characterized in terms of initial enrichment, bumup, dimension, gross weight and age. Also the isotopic composition and the radiological properties are quantitatively identified. This information provided in this study could be used as input for repository system development and performance assessment and applied in fuel material balance evaluation for the various types of back-end fuel cycle studies.

• 음성과학
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• 제7권1호
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• pp.217-232
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• 2000

In this study, I investigate the role of post-consonantal fundamental frequency (F0) as a cue for automatic distinction of types of Korean stops and affricates. Rather than examining data obtained by restricting contexts to a minimum to prevent the interference of irrelevant factors, a relatively natural speaker independent speech corpus is analysed. Automatic and statistical approaches are adopted to annotate data, to minimise speaker variability, and to evaluate the results. In spite of possible loss of information during those automatic analyses, statistics obtained suggest that vowel F0 is a useful cue for distinguishing manners of articulation of Korean non-continuant obstruents having the same place of articulation, especially of lax and aspirated stops and affricates. On the basis of the statistics, automatic classification is attempted over the relevant consonants in a specific context where the micro-prosodic effects appear to be maximised. The results confirm the usefulness of this effect in application for Korean phone recognition.

• Structural Engineering and Mechanics
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• 제22권6호
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• pp.647-664
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• 2006

The main purpose of this paper is to investigate the effect of transient stochastic analysis on nonlinear response of earth and rock-fill dams to spatially varying ground motion. The dam models are analyzed by a stochastic finite element method based on the equivalent linear method which considers the nonlinear variation of soil shear moduli and damping ratio as a function of shear strain. The spatial variability of ground motion is taken into account with the incoherence, wave-passage and site response effects. Stationary as well as transient stochastic response analyses are performed for the considered dam types. A time dependent frequency response function is used throughout the study for transient stochastic responses. It is observed that stationarity is a reasonable assumption for earth and rock-fill dams to typical durations of strong shaking.

• 한국환경과학회지
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• 제6권4호
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• pp.303-311
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• 1997

The characteristics of spring machanism In the Cheju Island were analyzed by statistical techniques. Basic characteristics, areal and altitudinal variations, and correlations of spring data were investigated. In this study. however, the subjects of the study are the 451 springs, the whole basin of Cheju Island derided Into four groups. In this study, analyzed the spring phenomena on the basis of both the geologic elements and the topogaphic elements. Also, the spring zone In Cheju Island are classified Into three types that the mountain area, the muddle area, the coastal area in spring distribution by attitude. The quentity of spring and variability show subvariety on the average according to Meinzer's classilfication and the whole basin of spring shows various distributions from Third to Sixth. The results of this study can be utilized to evaluate the condition of groundwater development In Cheju Island.

• 지식경영연구
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• 제8권1호
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• pp.1-14
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• 2007

This paper is an exploratory study providing critical research issues in knowledge management strategy, process operations, and knowledge management system design and control in mass customization. The firms implementing mass customization provide good cases adopting recent changes in business environment including increased diversity and variability of customer needs, fast development of related technologies, and increase of the necessity of knowledge management. In this study, required knowledge management characteristics are investigated and future research issues are suggested for successful implementations of knowledge management. Research issues are extracted from the context of strategy, process, and information system for the purpose of practical adaptation and the types of mass customization are emphasized as a mediating element for fit and consistency between firms' corporate strategy and knowledge management characteristics.

• 지역연구
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• 제12권2호
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• pp.79-97
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• 1996

Local dispute resolution has evolved in response to the need for effective ways to cope with the increasing numbers and types of local disputes. Where resources are limited, where the activities of individeuals or communities affect other individuals or communities, and where interests deviate or compete, disputes are likely to emerge. Efforts to resolve local disputes vary in their particulars but generally have certain elements in common. Therefore, this study focuses upon the fundamental directions and strategies for resolving local disputes. More specifically, the purpose of this study is to examine the causes of local disputes, to suggest fundamental directions for resolving local disputes, and then to explore the strategies for resovling local disputes. In the face of rising local disputes, planners need to become more aware of the possibilities for consensual dispute than one potential path to consensus. In spite of this variability, desirable strategies in local dispute resoultion processes can be identified.

• Journal of Plant Biology
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• 제38권4호
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• pp.321-328
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• 1995

Calli obtained from basal disc explants of Allium victorialis var.platyphyllum wre grown in three kinds of nutrient media (MS, BDS, and B5), and the frequencies of mitotic index and the chromosomal aberrations were analysed. The mitotic index varied from 0.55% to 1.01% with respect to culture media and ages. The mitotic irregularities like micro-, bi- and multi-nuclei, chromosome bridge and laggards were noted in each types of calli. The chromosome number variations observed in metaphase stage were identified aneuploid and tetraploid. Structural variations such as dicentric chromosomes, centromere breakage and small chromosomes were observed. Relationship between basal medium and chromosomal variability was not observed in this study. But, in BDS medium, NAA and BA had a more effect on number variation than kinetin.