• Korean Journal of Remote Sensing
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• v.25 no.3
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• pp.271-285
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• 2009

Multi-temporal satellite imagery can be changed into a transform image that emphasizes the changed area only through the application of various change detection techniques. From the transform image, an automated change detection model calculates the optimal threshold value for classifying the changed and unchanged areas. However, the model can cause undesirable results when the histogram of the transform image is unbalanced. This is because the model uses a single threshold value in which the sign is either positive or negative and its value is constant (e.g. -1, 1), regardless of the imbalance between changed pixels. This paper proposes an advanced method that can improve accuracy by applying separate threshold values according to the increased or decreased range of the changed pixels. It applies multiple threshold values based on the cumulative producer's and user's accuracies in the automated binary change detection model, and the analyst can automatically extract more accurate optimal threshold values. Multi-temporal IKONOS satellite imagery for the Daejeon area was used to test the proposed method. A total of 16 transformation results were applied to the two study sites, and optimal threshold values were determined using accuracy assessment curves. The experiment showed that the accuracy of most transform images is improved by applying multiple threshold values. The proposed method is expected to be used in various study fields, such as detection of illegal urban building, detection of the damaged area in a disaster, etc.

• Journal of Korean Clinical Nursing Research
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• v.17 no.1
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• pp.101-112
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• 2011

Purpose: The purpose of this study is to develop a detailed clinical model for recording initial nursing assessment items, and to test the applicability of the model to facilitate semantic interoperability for sharing and exchanging nursing information. Methods: First, the researchers extracted items by analyzing initial nursing assessment records. Second, defining characteristics were identified by analyzing nursing records and reviewing the literature. Third, value sets for defining characteristics were identified and types and cardinalities of defining characteristics were defined based on the value sets. Finally, the detailed clinical model was tested through evaluation by experts and comparison with the initial nursing assessment in a clinical setting. Results: Sixty-one detailed clinical models were developed with 178 defining characteristics and value sets. The experts evaluation and comparison with the initial nursing assessment in a clinical setting showed that the detailed clinical model developed in this study was valid. Conclusion: Use of this detailed clinical model can ensure that the Electronic Health Record contains meaningful and valid information and supports semantic interoperability of nursing information. This use will promote quality in the nursing records and eventually quality of nursing care.

• Journal of Korea Multimedia Society
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• v.25 no.10
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• pp.1448-1456
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• 2022

This paper studies a model to diagnose efficiency reduction of inverter using Multilayer Perceptron(MLP). In this study, two inverter data which started operation at different day was used. A Multilayer Perceptron model was made to predict photovoltaic power data of the latest inverter. As a result of the model's performance test, the Mean Absolute Percentage Error(MAPE) was 4.1034. The verified model was applied to one-year-old and two-year-old data after old inverter starting operation. The predictive power of one-year-old inverter was larger than the observed power by 724.9243 on average. And two-year-old inverter's predictive value was larger than the observed power by 836.4616 on average. The prediction error of two-year-old inverter rose 111.5572 on a year. This error is 0.4% of the total capacity. It was proved that the error is meaningful difference by t-test. The error is predicted value minus actual value. Which means that PV system actually generated less than prediction. Therefore, increasing error is decreasing conversion efficiency of inverter. Finally, conversion efficiency of the inverter decreased by 0.4% over a year using this model.

• Communications for Statistical Applications and Methods
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• v.30 no.1
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• pp.75-94
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• 2023

The growing trend of cyber risk has put forward the importance of cyber risk management. Cyber risk is defined as an accidental or intentional risk related to information and technology assets. Although cyber risk is a subset of operational risk, it is reported to be handled differently from operational risk due to its different features of the loss distribution. In this study, we aim to detect the characteristics of cyber loss and find a suitable model by measuring value at risk (VaR). We use the loss distribution approach (LDA) and the time series model to describe cyber losses of financial and non-financial business sectors, provided in SAS^® OpRisk Global Data. Peaks over threshold (POT) method is also incorporated to improve the risk measurement. For the financial sector, the LDA and GARCH model with POT perform better than those without POT, respectively. The same result is obtained for the non-financial sector, although the differences are not significant. We also build a two-dimensional model reflecting the dependence structure between financial and non-financial sectors through a bivariate copula and check the model adequacy through VaR.

• Journal of Environmental Science International
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• v.21 no.8
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• pp.965-975
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• 2012

Loading of NPS pollutant was valued through simulation by using BASINS/HSPF model which can simulate runoff volume in rainfall by time. For the verification of the model, it was analyzed the scatter diagram of the simulation value and measure value of water quality and runoff volume in Dongcheon estuary. Using the built model, a study on the time-variant characteristics of runoff and water quality was simulated by being classified into four cases. The result showed the simulation value was nearly same as that of the measured runoff. In the result of fit level test for measured value and simulated value, correlation of runoff volume was computed high by average 0.86 and in the water quality items, fit level of simulation and measurements was high by BOD 0.82, T-N 0.85 and T-P 0.79.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.326-335
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• 2017

This study investigates what consumption values affect attitude and behavioral intentions toward a premium lunch box at a convenience store using VAB(Value-Attitude-Behavior) model. The main survey was conducted by a research company by means of an online survey in the form of a self-administered questionnaire. The samples were limited to customers who had tried the premium lunch box before. The survey was conducted in October 2016. The collected data were analyzed by using SPSS 21.0 for Windows and AMOS 21.0. A structural equation model(SEM) was used to verify the proposed relationships among the study variables. Three factors representing the value of the premium lunch box were identified: social & functional value, economic value, and epistemic value. The finding showed that these values had a positive effect on attitude toward the premium lunch box and that attitude had a positive effect on behavioral intentions.

• Transactions of Materials Processing
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• v.24 no.6
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• pp.395-399
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• 2015

A microstructure-based finite element simulation was conducted to predict the plastic strain ratio (R-value) of a dual-phase (DP) steel. The representative volume elements (RVEs) concept was adopted for the image-based FE modeling and a 3D model was constructed using sequential 2D images. Each phase was considered with the von-Mises yield criterion and the Swift model. The Swift parameters were defined by the empirical equations based on the chemical composition. The developed model was applied to analyze the effect of residual stress on the R-value and stress distribution. In order to consider the residual stress development after cold rolling, 10 % compression was applied in the thickness direction and unloaded before the tensile stress was applied in the rolling direction. The results showed a reasonable prediction for the R-value evolution: a sharp increase at small strains was well described and a transition followed in the downward direction. The R-value evolution was analyzed using the stress distribution change on the π-plane

• Journal of Technology Innovation
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• v.4 no.1
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• pp.165-183
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• 1996

In acquiring and transferring a superior knowledge assesing the intermediate result value of a competitive R&D project is very important for a firm engaging in R&D. Most existing literatures on R&D evaluation are concerned with project selection and resource allocation. In this paper the stage of an R&D project is classified into research, exploratory development, and development. And a model is suggested which evaluates the intermediate result value before completion of development stage under duopoly and oligopolistic competition. Assessed value of the intermediate result transferred to the next tier company can be used as a minimum acceptable price to the inventor when more advanced knowledge acquired through R&D is transferred to the next tier one. The model suggested is composed of structural variables including research cost, success rates, potential profits, discount rate degree of competition. By using exponential distribution for invertion process time in each stage, we derive a formula that can assess the value of the intermediate result, and we demonstrate how the model can be applied to a competitive R&D situation through an example.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.1
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• pp.65-85
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• 1999

Objectives: To determine the effect of interpolation functions when processing the digital periapical images. Material and Methods: The digital images were obtained by Digora and CDR system on the dry skull and human subject. 3 oral radiologists evaluated the 3 portions of each processed image using 7 interpolation methods, and ROC curves were obtained by trapezoidal methods. Results: The heighest Az value(0.96) was obtained with cubic spline method and the lowest Az value(0.03) was obtained with facet model method in Digora system. The heighest Az value (0.79) was obtained with gray segment expansion method and the lowest Az value(0.07) was obtained with facet model method in CDR system. There was significant difference of Az value in original image between Digora and CDR system at a=0.05 level. There were significant differences of Az values between Digora and CDR images with cubic spline method, facet model method, linear interpolation method and non-linear interpolation method at α=0.1 level.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.939-947
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• 2020

The aim of this research was to empirical examine the influence of brand trust, perceived value on brand preference, and purchase intention for branded phones. The samples were gathered by a convenient sampling method. We collected data from 285 consumers who were visiting electronic supermarkets in Ho Chi Minh City, Vietnam. The measurement used a 5-point Likert scale ranging from 1=completely disagree, and 5=completely agree. PLS - Partial Least Squares method was performed to analyze the measurement model and the structural model. The study model was proposed from prior research. We had assessed the reliability of the scales through Cronbach's alpha and composite reliability. As well, we also had evaluated discriminant validity through the Fornell-Larcker criterion. The findings of the study demonstrated that brand trust had a significantly positive influence on brand preference. Likewise, the findings of the research also stated that brand trust had a positive impact on purchase intention. The results revealed that perceived value had a positive effect on brand preference. Furthermore, the outcomes show that perceived value had a positive influence on purchase intention as well. Furthermore, the findings of the research showed that brand preference had a positive effect on purchase intention.