• 한국연소학회지
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• 제9권4호
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• pp.1-8
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• 2004

Zone conditional formulation for the Reynolds average reaction progress variable is used to derive an asymptotic expression for turbulent burning velocity. New DNS runs are performed for validation in a statistically one dimensional steady state configuration. Parametric study is performed with respect to turbulent intensity, integral length scale, density ratio and laminar flame speed. Results show good agreement between DNS results and the asymptotic expression in terms of measured maximum flame surface density and estimated turbulent diffusivity in unburned gas.

• 한국심리학회지 : 문화 및 사회문제
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• 제19권2호
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• pp.235-257
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• 2013

본 연구는 여가강박 척도를 개발하고 타당화하기 위해 수행되었다. 이를 위해 여가강박을 개념화한 김용희의 연구(2008)를 바탕으로 도출한 문항들을 수정 및 통합하여 21개의 여가강박 예비문항을 구성하였다. 여가강박 예비문항을 사용하여, 200명의 기혼 직장인(30~50대)을 대상으로 탐색적 요인분석을 실시한 결과, 11개의 문항으로 구성된 2개의 하위요인(여가집착, 여가고정관념)이 여가강박의 요인구조로 가장 적합한 것으로 나타났다. 이러한 여가강박 요인구조의 타당성을 확인하기 위해 또 다른 기혼 직장인(30~50대) 200명의 응답자들로부터 자료를 수집하여 확인적 요인분석을 실시한 결과, 본 연구에서 추출한 2개 요인구조의 타당성이 지지되었고, 여가강박 척도의 총점 및 하위 요인들의 내적 합치도가 적절하였다. 전체 참가자(n=400)를 대상으로, 본 연구에서 개발된 여가강박 척도가 이와 유사한 개념을 측정하는 기존 척도들과 변별되는지 확인한 결과, 여가의 부정적 경험과 관련된 여가제약 및 여가불안 척도들은 물론, 강박증적 성향을 측정하는 강박증 및 일중독 척도들과 구분됨을 확인했다. 또한, 여가강박 척도의 준거관련 타당도를 확인한 결과, 여가강박 정도는 여가 정보탐색, 새로운 여가 참여의향 및 여가시간 증가의향과 유의미한 정적상관을 보여, 여가강박 척도가 준거변인들과 유의하게 관련되어 있는 것으로 밝혀졌다. 본 연구는 개념상으로만 존재하던 여가강박의 구성요인들을 확인하고 각 하위요인의 특성을 탐색했으며, 여가강박 척도의 요인구조에 대한 안정성 및 변별타당도와 준거타당도를 검증했다는 점에서 그 의의를 가진다.

• Journal of the Korean Data and Information Science Society
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• 제20권5호
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• pp.905-912
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• 2009

We propose a doubly penalized kernel machine (DPKM) which uses heteroscedastic location-scale model as basic model and estimates both mean and volatility functions simultaneously by kernel machines. We also present the model selection method which employs the generalized approximate cross validation techniques for choosing the hyperparameters which affect the performance of DPKM. Artificial examples are provided to indicate the usefulness of DPKM for the mean and volatility functions estimation.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권2호
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• pp.142-148
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• 2005

This paper proposes a cell age model for Penicillium chrysogenum fed-batch cultivation to supply a qualitative insight into morphology-associated dynamics. The average ages of the segregated cell populations, such as growing cells, non-growing cells and intact productive cells, were estimated by this model. A combined model was obtained by incorporating the aver-age ages of the cell sub-populations into a known but modified segregated kinetic model from literature. For simulations, no additional effort was needed for parameter identification since the cell age model has no internal parameters. Validation of the combined model was per-formed by 20 charges of industrial-scale penicillin cultivation. Meanwhile, only two charge-dependent parameters were required in the combined model among approximately 20 parameters in total. The model is thus easily transformed into an adaptive model for a further application in on-line state variables prediction and optimal scheduling.

• Journal of Preventive Medicine and Public Health
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• 제40권2호
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• pp.108-113
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• 2007

When conducting large-scale cohort studies, numerous statistical issues arise from the range of study design, data collection, data analysis and interpretation. In genomic cohort studies, these statistical problems become more complicated, which need to be carefully dealt with. Rapid technical advances in genomic studies produce enormous amount of data to be analyzed and traditional statistical methods are no longer sufficient to handle these data. In this paper, we reviewed several important statistical issues that occur frequently in large-scale genomic cohort studies, including measurement error and its relevant correction methods, cost-efficient design strategy for main cohort and validation studies, inflated Type I error, gene-gene and gene-environment interaction and time-varying hazard ratios. It is very important to employ appropriate statistical methods in order to make the best use of valuable cohort data and produce valid and reliable study results.

• 종양간호연구
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• 제10권1호
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• pp.59-67
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• 2010

Purpose: The purpose of this study was the development and validation of knowledge scale for patients with breast cancer (KS-Br) in Korea. Methods: The process included the construction of a conceptual framework, generation of preliminary items, and the test of validity and reliability of the scale. Thirty-seven items were developed through an evaluation process by 10 experts and 24 items were finally confirmed through item analysis. Psychometric testing was performed with a convenient sample of 303 women with breast cancer. The data was analyzed using independent t-test, Pearson's correlation, and calculation of KR-20. Results: Participants averaged 70.8% correct on the test. The KS-Br has 24 items consisting of 5 categories: incidence of breast cancer, diagnosis and treatment, symptom management, sexuality, and maintenance of daily life. Validity was supported by the use of content validity, known-group technique, and criterion-related validity. Women who had undergone education intervention scored significantly higher than women who had not (p<.001). KS-Br scores were significantly correlated with those of Mishel's Illness Uncertainty Scale (r=-.214, p<.001). Internal consistency of the KS-Br was appropriate (KR20=.805). Conclusion: This study reveals that the KS-Br is reliable and valid scale to measure the knowledge of breast cancer. Therefore, this scale can be effectively utilized to assess the knowledge of patients with breast cancer regarding their disease.

• Archives of Plastic Surgery
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• 제48권3호
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• pp.269-277
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• 2021

Background The Sunnybrook facial grading scale is a comprehensive scale for the evaluation of facial paralysis patients. Its results greatly depend on subjective input. This study aimed to develop and validate an automated Sunnybrook facial grading scale (SBface) to more objectively assess disfigurement due to facial paralysis. Methods An application compatible with iOS version 11.0 and up was developed. The software automatically detected facial features in standardized photographs and generated scores following the Sunnybrook facial grading scale. Photographic data from 30 unilateral facial paralysis patients were randomly sampled for validation. Intrarater reliability was tested by conducting two identical tests at a 2-week interval. Interrater reliability was tested between the software and three facial nerve clinicians. Results A beta version of the SBface application was tested. Intrarater reliability showed excellent congruence between the two tests. Moderate to strong positive correlations were found between the software and an otolaryngologist, including the total scores of the three individual software domains and composite scores. However, 74.4% (29/39) of the subdomain items showed low to zero correlation with the human raters (κ<0.2). The correlations between the human raters showed good congruence for most of the total and composite scores, with 10.3% (4/39) of the subdomain items failing to correspond (κ<0.2). Conclusions The SBface application is efficient and accurate for evaluating the degree of facial paralysis based on the Sunnybrook facial grading scale. However, correlations of the software-derived results with those of human raters are limited by the software algorithm and the raters' inconsistency.

• 한국콘텐츠학회논문지
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• 제22권7호
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• pp.583-598
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• 2022

본 연구의 목적은 소셜미디어 정서전염척도(Social Media Emotional Contagion Scale, SECS)를 개발하고 타당화를 하는 것이다. 전국의 20대 성인을 대상으로 결측을 제외한 총 326명을 대상으로 진행되었으며, SECS의 높은 신뢰도를 확보하였다. EFA와 CFA를 통해 SECS가 2요인 구조임을 확인하였고 한국판 정서전염 척도(K-ECS), 성인 공감척도(BES-A), Rosenberg 자아존중감척도(SES)와의 준거관련타당도를 확인하였다. SECS는 K-ECS와 BES-A의 정서적 전염과 관련된 하위요인과는 수렴하였지만, K-ECS와 BES-A 전체 척도와는 변별되었다. 이는 오프라인상에서 나타나는 정서전염과 소셜미디어상에서 나타나는 정서전염을 구별할 필요성을 시사한다. SES와는 변별되었으나 SES의 하위요인과는 일부 수렴하고 일부 변별되었다. 더 나아가, IRT를 시행하여 SECS가 높은 변별도와 적절한 심각도 문항으로 구성된 타당한 척도임을 확인하였다. 마지막으로, SECS 척도의 기준점을 제시하였고 본 연구의 의의와 제한점 및 추후 연구에 대해 논의하였다.

• 아동학회지
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• 제27권2호
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• pp.195-213
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• 2006

Development of the 3 scales comprising the present research was based on review of literature, existing screening scales, and empirical research pertaining to (Scale I) the development of social and emotional problems of children, (Scale II) parent-child relations, and (Scale III) assessment of children's environment. Professionals in each area approved a draft of the new screening scale. The clinical group was classified into normal and at-risk groups based on the Denver II scale and the Child Behavior Check List(ages 1.5-5). The clinical groups were administered the newly developed screening scale to see whether the same classification pertained. Results proved the cross-validity of the new scale.

• Near Infrared Analysis
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• 제1권1호
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• pp.1-7
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• 2000

A convenient algorithm for optimizing wavelength selection in multiple linear regression (MLR) has been developed. MOP (MLP Optimization Program) has been developed to test all possible MLR calibration models in a given spectral range and finally find an optimal MLR model with external validation capability. MOP generates all calibration models from all possible combinations of wavelength, and simultaneously calculates SEC (Standard Error of Calibration) and SEV (Standard Error of Validation) by predicting samples in a validation data set. Finally, with determined SEC and SEV, it calculates another parameter called SAD (Sum of SEC, SEV, and Absolute Difference between SEC and SEV: sum(SEC+SEV+Abs(SEC-SEV)). SAD is an useful parameter to find an optimal calibration model without over-fitting by simultaneously evaluating SEC, SEV, and difference of error between calibration and validation. The calibration model corresponding to the smallest SAD value is chosen as an optimum because the errors in both calibration and validation are minimal as well as similar in scale. To evaluate the capability of MOP, the determination of benzene content in unleaded gasoline has been examined. MOP successfully found the optimal calibration model and showed the better calibration and independent prediction performance compared to conventional MLR calibration.