• 한국과학교육학회지
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• 제34권6호
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• pp.583-592
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• 2014

이 연구는 글쓰기를 활용한 논의-기반 모델링 전략이 학생들의 모델링 능력에 미치는 영향을 알아보는 것을 목적으로 하였다. 또한 논의-기반 모델링 전략에서 다중표상의 적용여부가 학생들의 모델링 능력에 미치는 효과를 비교하였다. 이를 위해 남녀공학 중학교 1학년 세 개 학급(66명) 중 두 개 학급(43명)은 실험집단으로, 한 개 학급(23명)은 비교집단으로 선정하였다. 논의-기반 모델링 전략을 적용한 두 개 실험집단 중에서 한 개 학급은 AbRM집단(Argument-based multimodal Representation and Modeling, 논의-기반 다중표상 및 모델링 집단, 22명), 다른 한 개 학급은 AbM집단(Argument-based Modeling, 논의-기반 모델링 집단, 21명), 나머지 한 개 학급은 비교집단(23명)으로 선정하였다. 논의-기반 모델링 전략은 인지 과정, 해석 과정, 적용과정으로 구성되어 있다. 실험집단은 논의-기반 모델링 전략의 인지과정과 해석 과정을 공통적으로 수행하고 적용 과정에서 차이를 두었다. AbRM집단은 논의-기반 다중표상 및 모델링을 적용하였고, AbM 집단은 논의-기반 모델링을 적용했으며, 비교집단은 전통적 수업방식을 적용하였다. 논의-기반 모델링 전략이 학생들의 모델링 능력에 미치는 영향을 분석한 결과, AbRM집단의 경우 통합적 모델링 수준에서 다른 두 집단보다 통계적으로 유의미하게 높았고, AbM집단은 비교집단보다 유의미하게 높았다. 모델링 능력 검사의 하위요소인 문제인식, 과학개념 구조화, 주장-증거 적절성, 다중표상 지수에서 AbRM집단의 경우 모든 하위요소에서 AbM집단과 비교집단 보다 통계적으로 유의미하게 높았으며, 그 다음으로 AbM집단이 비교집단 보다 통계적으로 유의미하게 높았다. 이러한 결과로부터 논의-기반 모델링 전략은 모델링의 목적인 의사소통을 위해 자신이 만든 모델을 논의와 글쓰기를 통해 과학적 언어를 사용하여 스스로 정리하거나 표현하고, 다른 사람의 의견을 듣고 교환하는 과정을 통해 모델을 평가하고 수정하는 일련의 과정을 통해서 학생들의 모델링 능력의 향상에 효과적임을 보여주었다.

• 한국농공학회논문집
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• 제54권6호
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• pp.53-63
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• 2012

The objectives of this study were to develop a linked watershed-waterbody modeling system and to assess the impacts of indirect wastewater reuse on irrigation water quality. The Osan stream watershed within Gyeonggi-do of South Korea was selected for this study. The linked modeling system was composed of the SWAT (Soil and water assessment tool) and QUALKO2 models. The SWAT model was calibrated and validated using the stream discharge and water quality data from 2010 to 2011. Runoff and non-point source pollutants from each subbasin and stream discharge from 1980 to 2009 were simulated by the SWAT model and applied to the QUALKO2 model. The QUALKO2 model was calibrated and validated under the conditions of low water and normal discharges, respectively. Finally, The 10-day irrigation water quality from April to September was simulated. The statistical measures of coefficient of determination ($R^2$), reliability index (RI), and efficiency index (EI) were used to evaluate the system performance. The $R^2$, RI and EI values ranged from 0.5 to 1.0, 1.03 to 1.92, and -35.03 to 0.95, respectively. The 10-day irrigation water quality showed the concentrations of BOD and coliform exceeded the water quality guidelines for wastewater reuse. The linked modeling system can be a useful tool to estimate non-point source pollutant loads in watershed and to control the water quality of effluent from a wastewater treatment plant and irrigation water in the downstream waterbody.

• 한국정보통신학회논문지
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• 제23권7호
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• pp.764-770
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• 2019

본 연구에서는 "4차 산업"과 관련된 논문들의 세부 연구 주제를 파악하기 위하여 텍스트 마이닝 기법을 이용하여 논문들을 분석하였다. 이를 위하여 2016년부터 2019년까지 한국학술지인용색인(KCI)에서 "4차 산업"이라는 키워드로 논문을 검색하여 총 685편의 논문을 수집하였다. 논문 수집을 위해서는 Python 기반의 웹 스크랩핑 프로그램을 사용하였으며, 자료 분석을 위해서는 R 언어로 구현된 LDA 알고리즘 기반의 토픽 모델링 기법들을 활용하였다. 수집된 논문들에 대한 Perplexity 분석 결과, 9가지 토픽이 최적으로 결정되었고 수집된 논문들의 9가지 대표 토픽들을 Gibbs 샘플링 방법을 사용하여 추출하였다. 분석 결과, 인공지능, 빅데이터, 사물인터넷, 디지털, 네트워크 등이 상위 주요 기술들로 나타났으며, 산업, 정부, 교육 현장, 일자리 등 4차 산업과 관련한 다양한 분야에서 주요 기술들로 인한 변화에 대한 연구들이 이루어져 왔음을 확인할 수 있었다.

• 소프트웨어공학소사이어티 논문지
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• 제24권3호
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• pp.91-99
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• 2011

국가 방위를 위한 무기체계의 획득은 다른 분야와 비교할 때 상대적으로 비용이 과다히 소모되고, 획득자원의 시험과정 등이 매우 위험하며 획득결과의 품질이 매우 중요하다. 이러한 무기체계 획득의 특성으로 인해서 모의실험이 필수적으로 이루어지고 있으며, 이를 시뮬레이션 기반 획득(SBA, Simulation Based Acquisition) 이라고 한다. 그런데, 모의실험을 위한 모델개발 및 이의 실행분석이 갖는 비용이 무시할 수 없는 수준이기 때문에 모의실험이 갖는 효과도에 대한 분석에 대한 연구필요성이 제기되어 왔다. 본 연구에서는 이러한 효과도 분석에 요구되는 4가지의 지표를 제시하고, 이 지표들이 기존 연구에 어떻게 적용될 수 있는지에 대한 사례분석을 수행하였다. 비록 기존 연구들이 이러한 지표를 고려하지 않았지만, 본 논문에서 명시하고 있는 효과도에 대한 고찰을 통해 모의실험의 국방 획득 과정에서의 필요성을 확인 할 수 있다.

• 한국정보시스템학회지:정보시스템연구
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• 제31권1호
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• pp.289-304
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• 2022

Purpose The development of the network and mobile industries has induced companies to invest in information systems, leading a new industrial revolution. The Journal of Information Systems, which developed the information system field into a theoretical and practical study in the 1990s, retains a 30-year history of information systems. This study aims to identify academic values and research trends of JIS by analyzing the trends. Design/methodology/approach This study aims to analyze the trend of JIS by compounding various methods, named as TLS mining analysis. TLS mining analysis consists of a series of analysis including Term Frequency-Inverse Document Frequency (TF-IDF) weight model, Latent Dirichlet Allocation (LDA) topic modeling, and a text mining with Semantic Network Analysis. Firstly, keywords are extracted from the research data using the TF-IDF weight model, and after that, topic modeling is performed using the Latent Dirichlet Allocation (LDA) algorithm to identify issue keywords. Findings The current study used the summery service of the published research paper provided by Korea Citation Index to analyze JIS. 714 papers that were published from 2002 to 2012 were divided into two periods: 2002-2011 and 2012-2021. In the first period (2002-2011), the research trend in the information system field had focused on E-business strategies as most of the companies adopted online business models. In the second period (2012-2021), data-based information technology and new industrial revolution technologies such as artificial intelligence, SNS, and mobile had been the main research issues in the information system field. In addition, keywords for improving the JIS citation index were presented.

• Journal of Preventive Medicine and Public Health
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• 제50권2호
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• pp.83-90
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• 2017

Objectives: The aim of this study was to model the avoidable burden of the risk factors of road traffic crashes in Iran and to prioritize interventions to reduce that burden. Methods: The prevalence and the effect size of the risk factors were obtained from data documented by the traffic police of Iran in 2013. The effect size was estimated using an ordinal regression model. The potential impact fraction index was applied to calculate the avoidable burden in order to prioritize interventions. This index was calculated for theoretical, plausible, and feasible minimum risk level scenarios. The joint effects of the risk factors were then estimated for all the scenarios. Results: The highest avoidable burdens in the theoretical, plausible, and feasible minimum risk level scenarios for the non-use of child restraints on urban roads were 52.25, 28.63, and 46.67, respectively. In contrast, the value of this index for speeding was 76.24, 37.00, and 62.23, respectively, for rural roads. Conclusions: On the basis of the different scenarios considered in this research, we suggest focusing on future interventions to decrease the prevalence of speeding, the non-use of child restraints, the use of cell phones while driving, and helmet disuse, and the laws related to these items should be considered seriously.

• 전자공학회논문지
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• 제50권9호
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• pp.77-84
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• 2013

빠르게 일어나는 기술의 발전과 그 안에 내재된 문화적 현상을 결합하려는 시도를 문화 컴퓨팅, 문화 모델링이라 한다. 본 논문에서는 문화 모델링 연구 추세를 기반으로 문화 사용자 인터페이스 디자인, 특히 그 중에서도 콘텐츠를 중심으로 한 문화 기반 디자인 구조를 설명한다. 문화에 기반한 콘텐츠를 디자인하기 위해서는 콘텐츠의 문화적 특성을 도출하는 구조가 필요하다. 이를 위해 Hofstede의 문화 차원 모델과 콘텐츠 데이터를 결합하여, 콘텐츠 중심의 문화 차원 지수(CiCo) 구조를 새롭게 제안한다. 또한 도출한 CiCo와 국가별 콘텐츠 선호 패턴을 결합하여 국가별 콘텐츠 문화 차원 지수인 NiCC를 도출한다. 제안하는 CiCo와 NiCC는 기존의 Hofstede 모델에 기반하였으되, 기존 모델 대비 약 10% 개선된 설명력을 갖는다.

• 대기
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• 제28권4호
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• pp.403-414
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• 2018

Predictability of Northern Hemisphere blocking in the Korea Meteorological Administration (KMA) Global Data Assimilation and Prediction System (GDAPS) is evaluated for the period of July 2016 to May 2017. Using the operational model output, blocking is defined by a meridional gradient reversal of 500-hPa geopotential height as Tibaldi-Molteni Index. Its predictability is quantified by computing the critical success index and bias score against ERA-Interim data. It turns out that Northwest Pacific blockings, among others, are reasonably well predicted with a forecast lead time of 2~3 days. The highest prediction skill is found in spring with 3.5 lead days, whereas the lowest prediction skill is observed in autumn with 2.25 lead days. Although further analyses are needed with longer dataset, this result suggests that Northern Hemisphere blocking is not well predicted in the operational weather prediction model beyond a short-term weather prediction limit. In the spring, summer, and autumn periods, there was a tendency to overestimate the Western North Pacific blocking.

• Clinical and Experimental Reproductive Medicine
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• 제48권2호
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• pp.163-173
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• 2021

Objective: This study aimed to characterize a validated model for predicting oocyte retrieval in controlled ovarian stimulation (COS) and to construct model-based nomograms for assistance in clinical decision-making regarding the gonadotropin protocol and dose. Methods: This observational, retrospective, cohort study included 636 women with primary unexplained infertility and a normal menstrual cycle who were attempting assisted reproductive therapy for the first time. The enrolled women were split into an index group (n=497) for model building and a validation group (n=139). The primary outcome was absolute oocyte count. The dose-response relationship was tested using modified Poisson, negative binomial, hybrid Poisson-E_max, and linear models. The validation group was similarly analyzed, and its results were compared to that of the index group. Results: The Poisson model with the log-link function demonstrated superior predictive performance and precision (Akaike information criterion, 2,704; λ=8.27; relative standard error (λ)=2.02%). The covariate analysis included women's age (p<0.001), antral follicle count (p<0.001), basal follicle-stimulating hormone level (p<0.001), gonadotropin dose (p=0.042), and protocol type (p=0.002 and p<0.001 for short and antagonist protocols, respectively). The estimates from 500 bootstrap samples were close to those of the original model. The validation group showed model assessment metrics comparable to the index model. Based on the fitted model, a static nomogram was built to improve visualization. In addition, a dynamic electronic tool was created for convenience of use. Conclusion: Based on our validated model, nomograms were constructed to help clinicians individualize the stimulation protocol and gonadotropin doses in COS cycles.

• Child Health Nursing Research
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• 제26권1호
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• pp.35-46
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• 2020

Purpose: The purpose of this study was to test a model for intention to discontinuation drinking high caffeinated beverages among undergraduate students. This model was based on the Ajzen's theory of planned behavior and Becker's health belief model. Methods: Participants consisted of 201 undergraduate students. Data were collected by questionnaires from March 11 to May 24, 2019. Collected data were analyzed using SPSS/WIN 22.0, AMOS 22.0 program. Results: The assessment of the model indicated an acceptable fit (normed x²=1.65, goodness-of-fit index [GFI]=.83, adjusted GFI=.79, comparative fit index [CFI]=.92, standardized root mean square residual [SRMR]=.05, Tucker-Lewis index [TLI]=.91, normed fit index [NFI]=.87, root mean square error of approximation [RMSEA]=.07). Perceived behavior control, subjective norm, the subjective attitude was found to have a significant direct effect on the intention to discontinuation of drinking a high caffeinated beverage. The variances of this model explained 45.3% of the variance in intention to discontinuation of drinking a high caffeinated beverage. Conclusion: These results suggest that a need to increase awareness of adverse effects and potential risks of high caffeinated beverage consumption in undergraduate students. Besides, the university and government should provide education and campaigns to prevent excessive high-caffeinated beverage consumption.