• Journal of Wetlands Research
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• v.22 no.4
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• pp.275-285
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• 2020

In this study, after estimating VCI (Vegation Condition Index), TCI (Thermal Condition Index) and VHI (Vegetation Health Index) from the NDVI (Normalized Differentiation Vegetation Index) and LST (Land Surface Temperature) remotely sensed at major sites in Korea during the 2001-1919 period, the correlation between these indices and various drought indices is analyzed for the purpose of assessing the effects of ecological drought. The relative impact of VCI and TCI on vegetation health was found to vary by region. The effects of drought on vegetation in Korea's forest areas could be more clearly identified in TCI than in VCI. It is suggested that the revised VHI, reflecting the relative influence of VCI and TCI, can better explain the effects of drought on vegetation.

• YAKHAK HOEJI
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• v.42 no.5
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• pp.513-518
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• 1998

Fluoxetine is a nontricyclic antidepressant which blocks serotonin reuptake selectively. Its N-demethyl metabolite, norfluoxetine is also selective inhibitor of serotonin uptake . This study was carried out to compare the bioavailability of Myung-in fluoxetine (20mg/cap.) with that of Prozac$^{\circde{R}}$. The bioavailability was conducted on 24 healthy volunteers who received a single dose (80mg) of each drug in the fasting state, in a randomized balanced 2-way crossover design. After closing, serial blood samples were collected for a period of 48 hours, Plasma was analyzed for fluoxetine and norfluoxetine by a sensitive and validated HPLC assay. The major pharmacokinetic parameters ($AUC_{0-48\;hr}$, Cmax, Tmax , $AUC_{inf.}$, MRT. $T_{1/2}$, Vd and Cl) were, calculated from the plasma fluoxetine concentration-time data of each volunteer. The microcomputer program, 'WinNonlin' was used for compartmental analysis. A two-compartment model with first-order input, first-order output and no lag time was chosen as the most appropriate pharmacokinetic model. The data were best described by using a weighting factor of $1/y^2$. Though the plasma fluoxetine concentrations of Myung-in fluoxetine were higher than those of Prozac$^{\circde{R}}$ at all observed time from 7.9% to 16.9% (P<0.05 at 6.7 and 10 hr), the bioavailability of Myung-in fluoxetine appeared to be bioequivalent with that of Prozac$^{\circde{R}}$. There were no statistical significant differences between the two drugs in all pharmacokinetic parameters including $AUC_{0-48\;hr}$ of norfluoxetine.

• International Journal of Control, Automation, and Systems
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• v.2 no.4
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• pp.423-434
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• 2004

In this paper, we introduce a new topology of Self-Organizing Polynomial Neural Networks (SOPNN) based on genetically optimized Multi-Layer Perceptron (MLP) and discuss its comprehensive design methodology involving mechanisms of genetic optimization. Let us recall that the design of the 'conventional' SOPNN uses the extended Group Method of Data Handling (GMDH) technique to exploit polynomials as well as to consider a fixed number of input nodes at polynomial neurons (or nodes) located in each layer. However, this design process does not guarantee that the conventional SOPNN generated through learning results in optimal network architecture. The design procedure applied in the construction of each layer of the SOPNN deals with its structural optimization involving the selection of preferred nodes (or PNs) with specific local characteristics (such as the number of input variables, the order of the polynomials, and input variables) and addresses specific aspects of parametric optimization. An aggregate performance index with a weighting factor is proposed in order to achieve a sound balance between the approximation and generalization (predictive) abilities of the model. To evaluate the performance of the GA-based SOPNN, the model is experimented using pH neutralization process data as well as sewage treatment process data. A comparative analysis indicates that the proposed SOPNN is the model having higher accuracy as well as more superb predictive capability than other intelligent models presented previously.reviously.

• The KIPS Transactions:PartD
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• v.8D no.3
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• pp.233-240
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• 2001

As software technology is in progress and software quantification is getting more important, many metrics have been proposed to quantify a variety of system entities. These metrics can be classified into two different forms : scalar metric and metric vector. Though some recent studies pointed out the composition problem of the scalar metric form, many scalar metrics are successfully used in software development organizations due to their practical applications. In this paper, it is concluded that hybrid metric form weighting external complexity is most suitable for scalar metric form. With this concept, a general framework for hybrid metrics construction independent of the development methodologies and target system type is proposed. This framework was successfully used in two projects that quantify the analysis phase of the structured methodology and the design phase of the object oriented real-time system, respectively. Any organization can quantify system entities in a short time using this framework.

• YAKHAK HOEJI
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• v.58 no.2
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• pp.99-106
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• 2014

This study explores the prescribing pattern of generic drugs and the relationship between socio-demographic factors and the use of generics in South Korea. The analysis was based on claims data of 2011 from Korean National Health Insurance. We examined utilization, costs, and market share of oral preparations by original and generic product. Multiple logistic regression was performed to evaluate the predictive factors of generic use among multi-source medications. Generics accounted for 37~41% of utilization and 34~41% of costs in the insured market of oral preparations. In the generic market, costly generics made up about 58~61%, 56~66% of volume and value, respectively. Other things being equal, institutional factors affected generic use to the largest degree. The odds of having generics were 6 times higher in clinics, 4 times higher in hospitals, and 1.7 times higher in general hospitals than in teaching hospitals. Those in metropolitan or rural area were more likely to prescribe generics than those in the capital area. While generics were frequently prescribed for off-site pharmacy (OR=1.173), the odds of having generics was 0.88 after weighting the data by units prescribed. This study empirically presented the pattern of generic prescribing, confirming the widely accepted view that costly generics were more likely to be utilized in the Korean market. Up to two thirds of the generic market consisted of costly products. The strongest factors affecting generic use were institutional variables.

• Journal of Korea Water Resources Association
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• v.39 no.12 s.173
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• pp.1067-1080
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• 2006

In empirical evaluations of public projects and public provided goods, MCDA(multicriteria decision-making analysis) has helped decision makers with an adequate policy decision-making tool since it allows taking into account a wide range of assessment criteria. As a tool for decision-making of conflict management, MCDA has demonstrated its usefulness in many public projects such as road, dam and harbor construction. In this study, to use this merit of MCDA, dam project assessment indicators from points of social, economic, environmental and practical views are developed based on sustainable development of water resources, and weighting factors are also estimated by means of questionnaire survey. In order to decide project investment rank, developed evaluation indicators are applied to 6 existing dams under investigation for a rehabilitation project. In addition to, it is recognized that the project practicability has become more important indicator as well as environmental and social issues. This is because cooperation and support from a local government and people are regarded as one of the most important problems in public projects recently.

• Journal of the Korean Society for Railway
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• v.7 no.4
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• pp.332-338
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• 2004

The two projects about the high speed train have been performed in Korea, one project is the commercial run of high speed train(KTX) from Seoul to Busan and the other is the development of original high speed train(HSR 350x). As the successful results, the service run of KTX had been launched on the 1st of April, 2004 and HSR 350x had been fabricated in June, 2002 and has been tested in the Kyoungbu line and Honam line since then. The railway has the track irregularities which cause vibrations, such as rail joints, turnout, level crossing, transition curves and super-elevation ramps, and variations in the track level(z-axis) and the gauge(y-axis). Generally, the ride comfort for railway is evaluated by using the vibrations. In this paper, the ride comfort indices according to mc 513R and ISO 10056 have been reviewed when the high-speed trains are operated on both Kyoungbu line and Honam line. Also, the ride characteristics for KTX and HSR 350x on the high speed line and the conventional line have been analyzed and evaluated. The results show that the high-speed train has no problem from the viewpoint of the comfort ride on the high speed line and the conventional line and the ride index for HSR 350x is same as that for KTX in the high speed(300 km/h).

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.4
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• pp.1-9
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• 2015

This paper proposes CAC method that is more efficient for RRM using game theory combined with Multiple Attribute Decision Making(MADM). Because users request services with different Quality of Service(QoS), the network preference values to alternative networks for each service are calculated by MADM methods such as Grey Relational Analysis(GRA), Simple Additive Weighting(SAW) and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS). According to a utility function representing preference value, non-cooperative game is played, and then network provider select the requested service that provide maximum payoff. The appropriate service is selected through Nash Equilibrium that is the solution of game and the game is played repeated. We analyze two overlaid networks among four Wireless LAN(WLAN) systems with different properties. Simulation results show that proposed MADM techniques have same outcomes for every game round.

• Journal of Environmental Impact Assessment
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• v.2 no.1
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• pp.39-55
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• 1993

The importance of urban and regional natural park increases because of the needs for preserving the natural resources and providing with natural recreation space in nature. This planning of natural park management should be established based on the research of the various natural resources in the park. But for the lack of effective data synthesizing methods and concepts, only some restricted factors for zoning plan are considered even though GIS computer system for large complex simulation is used. Therefore, in this study three ecological zoning models such as Basic Factor Model (BFM), Visual Landscape Model (VLM) and Comprehensive Ecological Model (CEM) are proposed and applied to Byounsan Peninsula Nature Park(BPNP) for comparison with the current natural park zoning. The BFM has three components -elevation, slope and vegetation. The VLM has applied with six components -elevation, slope, vegetation, road type, and the visual distance. Finally the CEM's modelling factors have included all of BFM, VLM components are added with the land use type, nature and historic resource factors. The zoning concept of BPNP was based on "Minimization" focused on the specific factors. But introduced modelling concept is "Optimization" based on the total ecological environment. So the result of the modelling has larger area for preservation and development zoning compared with the current zoning whose characteristics are ambiguous which allows the environmental destruction. The future study issues will be the determination of the weighting factor, component reconsideration based on the ground truth data and the agriculture residential area zoning.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.155-155
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• 2012

최근 집중호우에 따른 자연재해가 크게 증가하여 수문 및 기상분야에서 강우를 관측 및 예측하기 위한 레이더 활용성이 증대되고 있으며, 이에 따라 정부 각 관련부처에서는 레이더의 도입 및 확충을 위한 방안을 계획 제시하고 있다. 특히, 레이더강우 자료는 수문해석분야에서의 GIS 등 디지털정보를 이용하여 유역매개변수를 추정함에 따라 더 정확하고 상세한 수문자료 확보가 가능하게 되어, 격자기반의 분포형 강우-유출모형 등을 이용하여 수문해석을 하는데 있어 그 활용성이 크게 증가하고 있다. 그러나 레이더강우 자료의 정확성은 아직까지 만족할 만한 수준에 이르지 못하고 있기 때문에, 그 불확실성으로 인하여 레이더강우 자료의 활용 및 적용에 한계를 가지고 있는 실정이다. 본 연구에서는 지상강우를 이용한 레이더강우 보정을 위하여 SOA(Statistical Objective Analysis)보정방법을 이용하였으며, 기존 SOA방법에서의 거리에 따른 가중치($_{kd}$)와 함께 지형(고도)에 따른 가중치($W_{ike}$), 바람의 영향에 따른 가중치($W_{ikw}$)를 추가로 산정하여 적용하였으며, 이를 통하여 보정된 강우장을 생성하였다. SOA방법을 통해 생성된 강우장이 어느 정도의 강우정확도를 가지고 강우분포를 재현하는지 검증하기 위하여 2011년 7~9월의 수문학적 분석에 활용 가능한 강우사상과 낙동강유역을 대상으로, 분포형모형인 $Vflo^{TM}$ 모형을 이용하여 산정된 유출량과 관측 유출량과의 비교를 실시하였다. 또한, 유출량에 대한 오차 및 ME(Model Efficiency)를 통해 레이더강우 자료의 유출모형에서의 효율성을 검토하고자 하였다. 본 연구에서 수행된 보정 강우장에 따른 유출량 비교를 통해 레이더 강우의 정확도에 대한 정량적 평가 방법 도출이 가능할 것으로 판단된다.