Documents disponibles écrits par cet auteur

Dynamic preventive maintenance scheduling of the modules of fighter aircraft based on random effects regression model / Sohn, S. Y. in Journal of the operational research society (JORS), Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 61 N° 6 (Juin 2010) . - pp. 974–979 Titre : Dynamic preventive maintenance scheduling of the modules of fighter aircraft based on random effects regression model Type de document : texte imprimé Auteurs : Sohn, S. Y., Auteur ; K. B. Yoon, Auteur Année de publication : 2011 Article en page(s) : pp. 974–979 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Dynamic  preventive  maintenance  Fighter  aircraft  Random  effects  Weibull-inverse  gamma  regression  model  MTBF  MTTR Index. décimale : 001.424 Résumé : Proper maintenance of fighter aircraft is an important issue to control the airpower. Typical maintenance policy applied is based on the constant schedule for a given module. This kind of maintenance does not take into account varying characteristics of the module over time. In this paper, we utilize the random effects Weibull regression model for non-constant MTBF (mean time between failure) and MTTR (mean time to repair) in order to provide a dynamic preventive maintenance schedule reflecting the module's varying characteristics in a timely manner. Our study is expected to contribute to ROKA (Republic of Korea Airforce) in terms of improving the level of combat readiness of fighter aircraft. DEWEY : 001.424 ISSN : 0361-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n6/abs/jors2008167a.html [article] Dynamic preventive maintenance scheduling of the modules of fighter aircraft based on random effects regression model [texte imprimé] / Sohn, S. Y., Auteur ; K. B. Yoon, Auteur . - 2011 . - pp. 974–979. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 61 N° 6 (Juin 2010) . - pp. 974–979 Mots-clés : Dynamic  preventive  maintenance  Fighter  aircraft  Random  effects  Weibull-inverse  gamma  regression  model  MTBF  MTTR Index. décimale : 001.424 Résumé : Proper maintenance of fighter aircraft is an important issue to control the airpower. Typical maintenance policy applied is based on the constant schedule for a given module. This kind of maintenance does not take into account varying characteristics of the module over time. In this paper, we utilize the random effects Weibull regression model for non-constant MTBF (mean time between failure) and MTTR (mean time to repair) in order to provide a dynamic preventive maintenance schedule reflecting the module's varying characteristics in a timely manner. Our study is expected to contribute to ROKA (Republic of Korea Airforce) in terms of improving the level of combat readiness of fighter aircraft. DEWEY : 001.424 ISSN : 0361-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n6/abs/jors2008167a.html

Pattern recognition for evaluator errors in a credit scoring model for technology-based SMEs / Sohn, S. Y. in Journal of the operational research society (JORS), Vol. 63 N° 8 (Août 2012) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 63 N° 8 (Août 2012) . - pp. 1051–1064 Titre : Pattern recognition for evaluator errors in a credit scoring model for technology-based SMEs Type de document : texte imprimé Auteurs : Sohn, S. Y., Auteur ; M. K. Doo, Auteur ; Y. H. Ju, Auteur Année de publication : 2012 Article en page(s) : pp. 1051–1064 Note générale : Operational research Langues : Anglais (eng) Mots-clés : Credit  scoring  model  for  technology-based  SMEs  Evaluator  effect  Decision  tree  Small  and  medium  enterprise  (SME) Index. décimale : 001.424 Résumé : A credit scoring model for technology-based small and medium enterprises presupposes evaluator objectivity and evaluation consistency; however, there is always some amount of error in any technology evaluation. This can be due in part to the subjective evaluation attributes that comprise part of the credit scoring model. The evaluated values of subjective attributes can vary among evaluators. In this study, we identified the significant characteristics of both evaluator and evaluation teams in terms of evaluation error using a decision tree analysis. Our results can improve the accuracy of a wide range of evaluation procedures for technology financing. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n8/abs/jors2011105a.html [article] Pattern recognition for evaluator errors in a credit scoring model for technology-based SMEs [texte imprimé] / Sohn, S. Y., Auteur ; M. K. Doo, Auteur ; Y. H. Ju, Auteur . - 2012 . - pp. 1051–1064. Operational research Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 63 N° 8 (Août 2012) . - pp. 1051–1064 Mots-clés : Credit  scoring  model  for  technology-based  SMEs  Evaluator  effect  Decision  tree  Small  and  medium  enterprise  (SME) Index. décimale : 001.424 Résumé : A credit scoring model for technology-based small and medium enterprises presupposes evaluator objectivity and evaluation consistency; however, there is always some amount of error in any technology evaluation. This can be due in part to the subjective evaluation attributes that comprise part of the credit scoring model. The evaluated values of subjective attributes can vary among evaluators. In this study, we identified the significant characteristics of both evaluator and evaluation teams in terms of evaluation error using a decision tree analysis. Our results can improve the accuracy of a wide range of evaluation procedures for technology financing. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n8/abs/jors2011105a.html

Survival analysis for technology credit scoring adjusting total perception / Moon, T. H. in Journal of the operational research society (JORS), Vol. 62 N° 6 (Juin 2011) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 62 N° 6 (Juin 2011) . - pp. 1159–1168 Titre : Survival analysis for technology credit scoring adjusting total perception Type de document : texte imprimé Auteurs : Moon, T. H., Auteur ; Sohn, S. Y., Auteur Année de publication : 2011 Article en page(s) : pp. 1159–1168 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Technology  scorecard  Perception  scoring  phenomenon  Survival  analysis  Binary  classification  Censoring  information Index. décimale : 001.424 Résumé : In the area of technology financing, the scorecard model is one of the most popular tools used to help organizations decide whether or not to grant loans to applicant firms. However, the scorecards are often filled-in based on the evaluator’s total perception rather than the individual attribute scores of which the scorecards are composed. Misleading results may occur when reversely scored individual attributes that are based on the total perception are used in the default prediction model. This paper proposes a survival model that takes into account not only the time to default but also the total perception scoring phenomenon. This proposed approach is expected to contribute to decision-making in various areas of technology, such as R&D investments, alliances, transfers, and loans. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v62/n6/abs/jors201080a.html [article] Survival analysis for technology credit scoring adjusting total perception [texte imprimé] / Moon, T. H., Auteur ; Sohn, S. Y., Auteur . - 2011 . - pp. 1159–1168. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 62 N° 6 (Juin 2011) . - pp. 1159–1168 Mots-clés : Technology  scorecard  Perception  scoring  phenomenon  Survival  analysis  Binary  classification  Censoring  information Index. décimale : 001.424 Résumé : In the area of technology financing, the scorecard model is one of the most popular tools used to help organizations decide whether or not to grant loans to applicant firms. However, the scorecards are often filled-in based on the evaluator’s total perception rather than the individual attribute scores of which the scorecards are composed. Misleading results may occur when reversely scored individual attributes that are based on the total perception are used in the default prediction model. This paper proposes a survival model that takes into account not only the time to default but also the total perception scoring phenomenon. This proposed approach is expected to contribute to decision-making in various areas of technology, such as R&D investments, alliances, transfers, and loans. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v62/n6/abs/jors201080a.html

Technology credit rating system for funding SMEs / Moon, T. H. in Journal of the operational research society (JORS), Vol. 62 N° 4 (Avril 2011) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 62 N° 4 (Avril 2011) . - pp. 608–615 Titre : Technology credit rating system for funding SMEs Type de document : texte imprimé Auteurs : Moon, T. H., Auteur ; Kim, Y., Auteur ; Sohn, S. Y., Auteur Année de publication : 2011 Article en page(s) : pp. 608–615 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Technology  rating  Technology  evaluation  Small  and  medium  enterprises Index. décimale : 001.424 Résumé : Technology evaluation has played a crucial role in selecting and supporting companies with innovative technology. Previous studies have focused on developing technology evaluation methods such as scorecard. However, technology credit rating is rarely applied, despite its convenient usage for technology financing. In this paper, we propose a technology credit rating system, called cross matrix, based on empirical data obtained from the technology scoring model and examine their properties. The proposed rating system is expected to provide valuable information for effective management of the technology credit fund. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v62/n4/abs/jors201015a.html [article] Technology credit rating system for funding SMEs [texte imprimé] / Moon, T. H., Auteur ; Kim, Y., Auteur ; Sohn, S. Y., Auteur . - 2011 . - pp. 608–615. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 62 N° 4 (Avril 2011) . - pp. 608–615 Mots-clés : Technology  rating  Technology  evaluation  Small  and  medium  enterprises Index. décimale : 001.424 Résumé : Technology evaluation has played a crucial role in selecting and supporting companies with innovative technology. Previous studies have focused on developing technology evaluation methods such as scorecard. However, technology credit rating is rarely applied, despite its convenient usage for technology financing. In this paper, we propose a technology credit rating system, called cross matrix, based on empirical data obtained from the technology scoring model and examine their properties. The proposed rating system is expected to provide valuable information for effective management of the technology credit fund. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v62/n4/abs/jors201015a.html

Technology credit scoring model considering both SME characteristics and economic conditions / Moon, T. H. in Journal of the operational research society (JORS), Vol. 61 N° 4 (Avril 2010) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 61 N° 4 (Avril 2010) . - pp. 666–675 Titre : Technology credit scoring model considering both SME characteristics and economic conditions : the Korean case Type de document : texte imprimé Auteurs : Moon, T. H., Auteur ; Sohn, S. Y., Auteur Année de publication : 2010 Article en page(s) : pp. 666–675 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Technology  evaluation  model  Environmental  condition  Small  and  medium  enterprise  Logistic  regression  model  Factor  analysis  Stress  test Index. décimale : 001.424 Résumé : In order to support small and medium enterprises (SME) with a high degree of growth potential in technology, various kinds of technology credit guarantees are issued to companies that obtain high scores by a technology scorecard in Korea. However, their default rates are reported to be very high. The main goal of this study is to propose a new technology evaluation model that accommodates not only technology-related attributes but also environmental conditions such as firm-specific characteristics and economic situations in the manner of more objective. We then show the superior prediction ability of the proposed model to the existing one. This model also enables to apply to a stress test by considering some worst environmental situations and is expected to be used for the effective management of the various technology funds for SMEs. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n4/abs/jors20097a.html [article] Technology credit scoring model considering both SME characteristics and economic conditions : the Korean case [texte imprimé] / Moon, T. H., Auteur ; Sohn, S. Y., Auteur . - 2010 . - pp. 666–675. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 61 N° 4 (Avril 2010) . - pp. 666–675 Mots-clés : Technology  evaluation  model  Environmental  condition  Small  and  medium  enterprise  Logistic  regression  model  Factor  analysis  Stress  test Index. décimale : 001.424 Résumé : In order to support small and medium enterprises (SME) with a high degree of growth potential in technology, various kinds of technology credit guarantees are issued to companies that obtain high scores by a technology scorecard in Korea. However, their default rates are reported to be very high. The main goal of this study is to propose a new technology evaluation model that accommodates not only technology-related attributes but also environmental conditions such as firm-specific characteristics and economic situations in the manner of more objective. We then show the superior prediction ability of the proposed model to the existing one. This model also enables to apply to a stress test by considering some worst environmental situations and is expected to be used for the effective management of the various technology funds for SMEs. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n4/abs/jors20097a.html