• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.116-127
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• 2011

This study conducted landslide susceptibility analysis using logistic regression. The performance of prediction model needs to be evaluated considering two aspects such as a goodness of fit and a prediction accuracy. Thus to gain more objective prediction results in this study, the prediction performance of the applied model was evaluated considering two such evaluation aspects. The selected study area is located between Inje-eup and Buk-myeon in the middle of Kwangwon. Landslides in the study area were caused by heavy rain in 2006. Landslide causal factors were extracted from topographic map, forest map and soil map. The evaluation of prediction model was assessed based on the area under the curve of the cumulative gain chart. From the results of experiments, 87.9% in the goodness of fit and 84.8% in the cross validation were evaluated, showing good prediction accuracies and not big difference between the results of the two evaluation methods. The results can be interpreted in terms of the use of environmental factors which are highly related to landslide occurrences and the accuracy of the prediction model.

• Ecology and Resilient Infrastructure
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• v.6 no.1
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• pp.1-11
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• 2019

This study performed the impact of ecological waterway on fish community in a reach of the Dal River, Korea. Fish monitoring revealed that 9 fish species are dominant, namely Zacco platypus, Coreoleuciscus splendidus, Zacco koreanus, Pungtungia herzi, Acheilognathus yamatsutae, Rhinogobius brunneus, Tanakia signifer, Gobiobotia macrocephala, and Pseudopungtungia tenuicorpus, and account for 95% of the total fish community. The River2D model was used for the computation of the flow and the HSI model for the habitat simulation. The restoration of the waterway performed through the small dam removal, the formation of the pool-riffle structure, and the change of the bed elevation and width. Simulation results indicated that the restoration of the ecological waterway effects significantly increased by about 16% for the WUA (Weighted Usable Area) of the total fish community in optimal ecological flow conditions ($Q=7.0m^3/s$). The restoration of the ecological waterway is more advantageous to fish community.

• Ecology and Resilient Infrastructure
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• v.6 no.2
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• pp.101-108
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• 2019

This study investigated the impact of abandoned channel restoration on fish habitat using the physical habitat simulation. The study area is a 1.2 km long reach of the Cheongmi-cheon stream. In the study area, the restoration of the abandoned channel was carried out from July 2012 to December 2105. Physical habitat simulations were carried out for both cases before and after the restoration. The River2D model and habitat suitability curve were used for hydraulic and habitat simulations, respectively. Zacco platypus, which is a dominant fish species in the study area, was selected as target fish for the physical habitat simulation. Hydraulic simulations were carried out before and after restoration for various discharges. Then, composite suitability index and weighted usable area were calculated before and after restoration and changes in the physical habitat of Zacco platypus were discussed. Simulation results indicated that the abandoned channel restoration is effective in creating fish habitat and mitigating the degradation of fish habitat from the high flow condition.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3B
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• pp.311-317
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• 2009

Similarity indices between sampling sites are calculated and cluster analysis of fish community is carried out by UPGMA based on investigating fish fauna and water environment. The restoration indicators as target species of Wonju stream are selected Cottus poecilopus, Zacco temmincki, and Zacco platypus along upper, middle, and lower streams, respectively. For better habitat suitability, low flow increasing and induced water quality improving must be secured by sewer system rearrangement and watershed management. Composite habitat suitability of Zacco temmincki as target species at middle stream of Wonju stream improve significantly by low flow increasing, which is very important factor to improve habitat suitability. The changes of hydraulics of depth and velocity govern the habitat suitability in general, but the effects are not significant. Low flow increasing with the change of 10% reducing of lower channel improves the composite habitat suitability of 0.37~0.78 to their origin of 0.1~0.25, which represent the channel restoration scheme of Wonju stream for enhancing the habitat suitability of fish community.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.146-148
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• 1999

문서분류의 문제점 중의 하나는 사용하는 데이터의 차원이 매우 크다는 것이다. 그러므로 문서에서 필요한 단어만을 자동적으로 추출하여 문서데이터의 차원을 축소하는 작업이 문서분류에서는 필수적이다. DF(Document Frequency)는 문서의 차원축소의 대표적인 통계적 방법 중 하나인데, 본 논문에서는 문서의 차원축소에 DF와 주성분 분석(PCA)을 비교하여 주성분 분석이 문서의 차원축소에 적합함을 실험적으로 보인다. 그리고 비선형 주성분 분석(nonlinear PCA) 방법 중 locally linear PCA와 kenel PCA를 적용하여 비선형 주성분 분석을 이용하여 문서의 차원을 줄이는 것이 선형 주성분 분석을 이용하는 것 보다 문서분류에 더 적합함을 실험적으로 보인다.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.274-284
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• 2020

In the era of the Fourth Industrial Revolution, the level of data-efficient utilization greatly affects the performance of the enterprise. This study was to verify the effect on organizational performance and the absorption capacity as a mediate, depending on person-job fit and person-organization fit in organizational memory affordance. According to a survey of 317 employees of large, medium and small businesses, organizations that have sufficient organizational memory have had a positive impact on both person-job fit(PJF) and person-organization fit(POF), and also on absorption capacity. In addition, the organizational memory affordance had a positive effect on absorption capacity by mediating the POF. PJF and POF had a positive effect on management performance, but only POF when mediating absorption capacity showed a positive influence relationship. This study is meaningful by comprehensively empirical analysis of the organizational IT construction environment and the members' perception of organization and job as a leading factor in absorption capacity, and simultaneously demonstrating the impact on organizational performance.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.559-571
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• 2020

This study was conducted to analyze the effects of person-environment fit on the job performance in the National Assembly legislative support organization. Job performance was classified into task performance, contextual performance, and adaptive performance. Impacts of each factors on the job performance were identified through structural equation model. From the results of analysis, it was confirmed that supplementary fit of officials of legislative support organization of the National Assembly had a positive effect on task performance, contextual performance, and adaptive performance. However, complementary-fit does not directly affect task performance, contextual performance, and adaptive performance. Rather complementary-fit affects job performance by the mediating role of variable self-efficacy. The implications of this study confirm that it is important to match between organization members and jobs in order to improve the job performance of civil servants in the legislative support organization. The necessity of introducing self-efficacy enhancement program into the education and training process of the legislative support organization was proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.11
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• pp.1050-1067
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• 2014

CAS(Close Air Support) is aircraft attack against hostile targets that are in close proximity to friendly forces. Immediate CAS is the mission that attack unplanned targets, and especially the distribution of suitable aircraft assets makes huge effect on the result of immediate CAS mission. But It is hard to find a previous studies on immediate CAS sortie distribution with aircraft suitability. This study suggests a methodology with aircraft suitability for immediate CAS sortie distribution. The methodology consists of 3 steps. Firstly, we analyze target information for situational awareness. Secondly, we calculate each aircraft's suitability value per each target based on the result of previous analysis. Lastly, we suggest immediate CAS sortie distribution based on the aircraft adoptability value to a decision maker. This methodology will provide not only quantitative analysis, but also decision making of immediate CAS sortie distribution more timely and effectively.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.1
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• pp.7-13
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• 2020

Purpose: This study was to evaluate marginal and internal discrepancy of 3-unit fixed dental prostheses (FDP) fabricated by subtractive manufacturing and additive manufacturing. Materials and methods: 3-unit bridge abutments without the maxillary left second premolar were prepared (reference model) and the reference model scan data was obtained using an intraoral scanner. 3-unit fixed dental prostheses were fabricated in the following three ways: Milled 3-unit FDP (MIL), digital light processing (DLP) 3D printed 3-unit FDP (D3P), stereolithography apparatus (SLA) 3D printed 3-unit FDP (S3P). To evaluate the marginal/internal discrepancy and precision of the prosthesis, scan data were superimposed by the triple-scan protocol and the combinations calculator, respectively. Quantitative and qualitative analysis was performed using root mean square (RMS) value and color difference map in 3D analysis program (Geomagic control X). Statistical analysis was performed using the Kruskal-Wallis test (α=.05), MannWhitney U test and Bonferroni correction (α=.05/3=.017). Results: The marginal discrepancy of S3P group was superior to MIL and D3P groups, and MIL and D3P groups were similar. The D3P and S3P groups showed better internal discrepancy than the MIL group, and there was no significant difference between the D3P and S3P groups. The precision was excellent in the order of MIL, S3P, and D3P groups. Conclusion: Within the limitation of this study, the 3-unit fixed dental prostheses fabricated by additive manufacturing showed better marginal and internal discrepancy than the those of fabricated by subtractive manufacturing, but the precision was poor.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1998.10a
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• pp.489-508
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• 1998

서비스 기업들은 경쟁우위를 달성하기위해 서비스 인카운터를 제고하는 것이 바람직하다. 서비스인카운터는 서비스파업, 서비스생산시스템, 서비스표준으로 구성되므로 이들간의 전략적 일관성에 노력을 기울여야 한다. 본 연구에서는 서비스 인카운터를 제고하기 위한 방안으로 서비스 기업의 경쟁전략과 하위전략인 MIS전략의 적합성을 경쟁전략, 서비스 생산구조, MIS과업, MIS전략구조로 파악하여 금융산업과 유통산업을 대상으로 실증분석을 수행했다. 실증분석결과 특히 경쟁전략과 MIS 과업, 그리고 경쟁전략과 서비스 생산구조간의 전략적 적합성이 가설을 높게 지지하는 것으로 나타났다.