• Journal of dental hygiene science
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• v.12 no.6
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• pp.617-623
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• 2012

This study was performed to measure the accuracy of different gypsum materials by a white light dental scanner. A master model with the prepared lower full arch tooth was used. The type IV and scannable stone were used for 20 stone casts (10 casts each) duplicated a master model of mandible. The distance between the reference points were measured and analyzed by the Delcam $Copycad^{(R)}$ (Delcam Plc, UK) 3D graphic software. The t-student test for paired samples were used for statistical analysis. The mean differences to master model for type IV stone and scannable stone model were 0.29~0.56 mm, and 0.17~0.35 mm, respectively. There were statistical differences in dimensional accuracy for full arch impression between the master model and type IV/scannable stone (p<0.05). Two different gypsum materials showed clinically acceptable accuracies of full arch digital impression produced by them. Besides, in both gypsum materials, the differences to the master model detected appear to provide enough accuracy for clinical application.

• Journal of the Korean Association of Geographic Information Studies
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• v.3 no.4
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• pp.63-72
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• 2000

The objective of this study was to identify the applicability of AGNPS(Agricultural Nonpoint Source Pollution) model using RS data; Landsat TM merged by KOMPSAT EOC and GIS data. AGNPS model which is well-known distributed nonpoint source pollution model was used as the assessment tool. This model has the capability to adjust the level of pollutant load from farmstead and the fertilization level of upland field. A small agricultural watershed($4.12km^2$) which has 20 livestock farmhouses located in Gosan-myun, Ansung-gun was selected. AGNPS data were prepared by using Arc/Info, GRASS, ER-Mapper and Idrisi. Four storm events in 1999 were used for runoff calibration, and 2 storm events which were measured in hourly-base at 4 locations along the stream were used for water quality(TN, TP) calibration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.537-543
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• 2016

This paper suggests a class model to improve the English oral proficiency for intermediate low English speaking learners. Utilizing the four English skills (reading, writing, listening and speaking), the class model focuses on the learners' schema and discussion strategies. To enhance the learners' motivation and match their cognitive capacity, 10 discussion topics were prepared by surveying the learners. A pilot experiment was conducted to investigate the teaching effects of the discussion class model with 26 college students majoring in English in Seoul. The participants' oral proficiency was measured both before, and after the instructions by OPIc (Oral Proficiency Interview in computer). As a result of the experiment, the percentage of participants whose oral proficiency levels were lower than intermediate mid decreased from 82% to 47%. In addition, the percentage of participants with higher oral proficiency than intermediate low was increased dramatically from 18% to 53%, which supports the claim that through discussion, the class learners' diverse and creative ideas need to be expressed in a formal and intelligible language. Finally, through the findings of the study, the possibility of a discussion class can be expected, regardless of the learners' low level of oral proficiency.

• Journal of Digital Convergence
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• v.9 no.4
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• pp.191-200
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• 2011

Smart work is a new paradigm of the way of working for knowledge workers. We propose a model which determines the levels of smart work. As the determinants, we identify freedom from both space and time. As an extension of the model by adding a new determinant of the mobilization of social intelligence, we show that a new smart work model, smart work 2.0, can be derived. For successful implementation of smart work 2.0, we also provide strategic suggestions, along with the implication of the study and future research direction.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.99-111
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• 2002

전산기술의 발달에 힘입어 근래에 모의실험을 이용한 연속교통류의 미시적 분석이 활발히 수행되고 있고 다양한 모의실험 전산모형이 소개되고 있다. 미시적 연속교통류 전산모의실험은 차량추종모형과 차로변경모형을 적용하여 다양한 운전자들의 차량운행행태를 모사하여 분석하는 실험이다. 전산모형은 난수를 토대로 차량의 자유속도와 초기 발생 차로를 배정하기 때문에 낮은 자유속도를 할당받은 차량이 높은 속도의 차로(예:1차로)로 발생되는 경우가 발생한다. 많은 모의실험모형이 사용하고 있는 차로변경의 가정이 "운전자는 자신이 원하는 속도(자유속도)를 유지한다"는 것이며 그러한 가정만의 적용으로 인해 현실적이지 않은 차로 이용률이 결과되고, 따라서 전산모형을 통한 교통류 흐름분석에 문제를 제공하고 있다. 본 논문에서는 미국 도로국에서 20여년 동안 개발되고 수정되어왔으며 현재 실용적으로 가장 많이 사용되고 있는 Freeway Simulation(FRESIM) 전산모형이 내재한 차로변경모형을 토대로 고속도로 기본구간에서의 선택적 차로변경모형을 제시한다. 제시된 모형에서는 (1)저속의 선행차량이 고속의 후행차량에게 차로를 양보하는 가정이 새롭게 추가되고 (2)FRESIM모형에서 사용하는 상수값을 국내 현장조사를 통하여 도출된 분포식을 통한 값으로 대체하였다. 수집된 자료분석결과 연속 교통류에서의 15% 차두시간은 1.34초이며 차로변경시간은 평균 2.22초인 F분포를 따르고, 자유속도는 정규분포를 따르는 것으로 결과되었다. 모의실험결과 무작위난수를 토대로 배정된 차로로 생성된 차량들이 새롭게 제시된 차로변경모형의 적용으로 현장 차로이용률을 95% 신뢰수준에서 모사하는 것으로 분석되었다.

• Environmental and Resource Economics Review
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• v.25 no.1
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• pp.89-112
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• 2016

In this paper, as a determining factor of the Environment Kuznets Curve hypothesis, we analyzed the impact of technological innovation. In this paper, in order to empirically validate the role of technological innovation to an inverted U-shaped Environments Kuznets Curve hypothesis, we utilize the 2SLS considering relationship between R&D and the GDP per capita. Also, using the Panel VAR (Panel Vector Auto Regression) model to analyze with what time lag R&D per capita has impact on the emissions of greenhouse gases per capita. Empirical results show that R&D per capita(proxy of innovation) is a important factor to explain Environmental Kuznets Curve hypothesis, and that the external shock such as R&D per capita reduces greenhouse gas emissions per capita with about 3 time lag.

• Survey Research
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• v.12 no.2
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• pp.113-144
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• 2011

The purposes of the present study were (1) to identify the latent classes depending on youth employees' trajectories in job satisfaction and turnover intention and (2) to test the effects of person-job fit(major fit, education level fit, skill level fit) on job satisfaction and turnover intention using Youth Panel 2001. In order to estimate latent classes of job satisfaction and turnover intention changes simultaneously and study probabilities linking latent class membership in trajectory across the two variables, we applied dual trajectory model, an extension of semi-parametric group-based approach, Results showed that four latent classes were identified for job satisfaction, which were defined, based on the trajectory patterns, as increasing group, decreasing group, medium-level group, and high-level group. And, three latent classes estimated for turnover intention were defined as low-level group, maintaining group, and rapidly decreasing group. To test the effects of person-job fit variables, we added the variables as time-dependant variables to the unconditional latent class model. The effect of education level fit and skill level fit were found significant in the groups which are low in job satisfaction and have high in turnover intention. Findings from this study suggest the need to consider trajectory heterogeneity in the study of youth employees' job satisfaction and turnover intention to capture the dynamic dimension of overlap between the two constructs.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.259-265
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• 2024

This paper analyzed the relationship between human resource development intent, human resource development implementation, firm's competitiveness. In addition, the indirect effect of organizational commitment was also assumed. The data for the research were integrated at the company level(500 companies) and used the data of 9,516 employees collected in the 2nd survey of "the Human Capital Company Panel II" of the "Korea Research Institute for Vocational Education and Training". The structural equation modeling was useed to analyze the analysing model. According to the analysis results, HRD intent had a positively significant effect on firm's competitiveness. And HRD implementation had a positively significant effect on firm's competitiveness. From the indirect effect through bootstrapping analysis, the organizational commitment showed indirect effects from HRD intent and HRD complementation to firm's competitiveness.

• Water for future
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• v.27 no.3
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• pp.55-69
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• 1994

In order to enhance the short-term flood forecasting accuracy of the water level of the In-do Brdg., three statistical flood forecasting models are presented models are presented and the forecasting accuracies and stabilities of the models are studied. The presented statistical models are as follows: The multi-input model by the multi-regression analysis between the water level of the In-do Brdg. and the influence parameters(Model MM). The two-level multi parameter model according to the water level tendency(Model 2MP). Among the three models, the Model MM showed the lowest forecasting accuracy, the model 2MP showed the highest forecasting accuracy, although this model sometimes became unstable and diverged. The model MMP forecasted the flood less accurately than model 2MP, but it gave more stable forecasting results.

• Journal of Cadastre & Land InformatiX
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• v.50 no.2
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• pp.237-254
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• 2020

Housing vacancies have become a major issue in urban areas, there have been many efforts to address this issue at the national and local levels. The purpose of this paper is to investigate the factors contributing to housing vacancies in old town Incheon in South Korea. In particular, the research focuses on examining the effects of multiple levels of factors on housing vacancies in a comprehensive way; the three levels of factors were identified with a literature review including housing (Level 1), Neighborhood (Level 2), and Region (Level 3). A multi-level logistic regression model was used to examine the relationship between 13 factors in three spatial levels and housing vacancies. As a result, the factors in all three levels were able to explain housing vacancies including site area and shape, proximity to major roads (Level 1), ratio of houses in designated urban renewal area and slope (Level 2), and ratio of the elderly living alone, land price, changes in land price and ratio of new houses (Level 3). These results show that the combination of the physical inferiority of the housing site and the neighborhood environment and the economic and social vulnerability of the region is likely to increases the number of vacant houses. This study also suggested that a multi-dimensional policy strategy is needed to solve the problem of housing vacancies, and urban policies, such as supplying new housing or urban renewal area designation, should be carefully implemented in a way not to create housing vacancies.