• Journal of Chest Surgery
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• v.32 no.6
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• pp.549-555
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• 1999

Background: Patients who are considered for major pulmonary resection are generally evaluated by spirometry and clinical assessment to predict morbidity and mortality. Despite this, none has yet proved to be a convenient and reliable estimate of risk. Material and Method: A retrospective analysis was performed in 167 patients who were diagnosed for lung cancer, bronchiectasis, pulmonary tuberculosis, and other benign pulmonary disease, and who underwent major lung resections. The relationship of 25 preoperative or postoperative variables to 19 postoperative events were classified into categories as operative mortality, pulmonary or cardiovascular morbidity, and other morbidity was assessed. Logistic regression analysis and $\chi$2 analysis were used to identify the relationship of the operative risk factors to the grouped postoperative complications. Result: The best single predictor of complications was the percent predicted postoperative diffusing capacity (pulmonary morbidity, p<0.009; cardiovascular morbidity, p<0.003: overall morbidity, p<0.004). Conclusion: The diffusing capacity of the lung for carbon monoxide was an important predictor of postoperative complications than the spirometry, and it usually should be a part of the evaluation of patients being considered for pulmonary resection.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.4
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• pp.373-378
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• 2002

This paper presents the results of an electromagnetic field uniformity of a triangular reverberation chamber that can be used alternatively for analysis and measurement of electromagnetic interference and immunity test. Equilateral triangular reverberation chamber and Schroeder diffusers were designed and fabricated for this purpose. FDTD simulation method was applied to analyze the field distribution inside of two different types of reverberation chambers. As a result, the electromagnetic field uniformity was improved inside of triangular reverberation chambers, and the measured field uniformity was improved by 1 ∼4 ㏈ compared to the ones without diffusers.

• Fire Science and Engineering
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• v.17 no.3
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• pp.61-73
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• 2003

Most of the accidents occurred from the chemical plants are related to the catastrophic gas release events when the large amount of toxic materials is leaked from its storage tank or transmitting pipe lines. In this case, the greatest concerns are how the spreading behaviors of leakages are depended on the ambient conditions such as air stability and other environmental factors. Hence, we have focused on the risk assessments and consequential analysis for chlorine as an illustrative example. As appeared in the result, Fire & Explosion Index depicted it a bit dangerous with presenting the comprehensive degrees of hazard 90.7. And as a result of Phast6.0/ALOHA, the trends of each scenario appeared considerably identical although there are some differences in the resulting effects according to the input data for the Gas Model. The consequence analysis is performed numerically based on the dense gas mode. In the future, using more correct input data, material properties, and topographical configuration, the method of this research will be useful for the guideline of the risk assessment when the release of toxicants breaks out.

• Asia Marketing Journal
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• v.11 no.1
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• pp.73-92
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• 2009

Consumers influence other consumers' brand choice behavior by delivering a variety of objective or subjective information on a particular product, which is called WOM (Word-Of-Mouth) activities. For WOM activities, WOM senders should choose messages to deliver to other consumers. We classify the contents of the messages a consumer chooses for WOM delivery into two categories: Subjective (positive or negative) evaluation and objective information on products. In our study, we regard WOM senders' activities as a choice behavior and introduce a choice model to study the relationship between the choice of different WOM information (WOM with positive or negative subjective evaluation and WOM with objective information) and its influencing factors (information sources and consumer characteristics) by developing two bivariate Probit models. In order to consider the mediating effects of WOM senders' product involvement, product attitude, and their characteristics (gender and age), we develop three second-level models for the propagation of positive evaluations, of negative evaluations, and of objective information on products in an hierarchical Bayesian modeling framework. Our empirical results show that WOM senders' information choice behavior differs according to the types of information sources. The effects of information sources on WOM activities differ according to the types of WOM messages (subjective evaluation (positive or negative) and objective information). Therefore, our study concludes that WOM activities can be partially managed with effective communication plans influencing on consumers' WOM message choice behavior. The empirical results provide some guidelines for consumers' propagation of information on products companies want.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.235-240
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• 2009

Simulation method based on probability was developed to evaluate the durability of reinforced concrete structures about chloride attack. The effects of the probability parameters(surface chloride ion concentration, initial combined chloride ion concentration, the depth of cover thickness of concrete, and the chloride ion diffusion coefficient), probability distribution function and it's variation were calculated using the Monte Carlo method and Fick's 2nd law. From the durability design method proposed in this study, the following results were obtained. 1) The effects of the distance from the coast and the chloride ion diffusion coefficient to the corrosion probability were quite high. 2) The effect of the variation of each parameters was relatively low.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.119-122
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• 2011

도심 건축물의 고층화가 빠르게 진행됨으로 인하여 국내외의 외장재 화재사고가 빈번히 발생하고 있다. 현재 국내 건축법에서는 외벽 마감재에 관한 관련법이 제정되어 있으나, 외장재의 수직 화재 확산에 대한 구체적인 화재안전성능 확보 기준 및 표준 시험 방법 등이 마련되어 있지 않다. 본 연구에서는 해운대 화재사고에 대한 사례 분석을 통하여 국내 제도 개선방향을 검토하고자 하였으며, 새로운 외장재 수직화재확산 성능 평가 기준 및 시헙법 도입을 제안하고자 하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2007.11a
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• pp.209-223
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• 2007

B2C, B2B와 같은 인터넷 상거래뿐만 아니라, 전자정부를 통한 G2C 등에서 보는 바와 같이, 공공 및 민간 IX(Internet exchange)를 통한 인터넷 상호연동 인프라는 명실상부한 사회 신경망으로 기능한다. 따라서 전통적인 사회간접자본인 도로, 항만, 전력 등에서와 마찬가지로, 그 구축 및 운영에서의 안정성과 신뢰성에 대한 요구가 점차 강화되고 있다 본 연구는 인터넷 상호연동망의 안정성과 신뢰성을 제고하기 위한 방안을 위험관리 관점에서 제안한다. 먼저, 인터넷 상호연동의 강건성(robustness)을 높이기 위한 방어기제와 더불어 상호연동 대안들을 개발한다. 이들 대안은 장애시에 작동하는 별도의 상호연동 비상망을 운영하는 방재형과, 지역적으로 분산된 상호연동 허브(IX)를 운영하여 장애에 따른 피해 확산을 방지하는 분산 허브형으로 구분된다. 본 논문에서는 또한 대안들의 위험효율성(risk efficiency)을 체계적으로 비교/평가하기 위하여 경영공학 방법론에 의한 위험평가 프레임워크를 개발하고, 이를 투자수준이 상이한 여러 대안들에 적용한다. 몬테카를로 시뮬레이션을 통한 ROI(Risk On Investment) 분석 결과, 방재형 대안이 비용 대비 위험효율성 측면에서 최선의 후보로 평가되었다.

• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.61-67
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• 1996

Environmental Impact Assessment (EIA) in Korea has worked toward environmental conservation and decision making since the Environmental Impact Statement of 1981. In order to implement the EIA process effectively, we have developed a system for and various methods of EIA. Among these methods, the Geographic Information System (GIS), which was introduced recently in Korea, can be used to integrate geographic and attribute data effectively. So GIS begins to increase the necessity of the application in EIA process. This study includes the integration method of the GIS and air dispersion model on the odor impact assessment of $NH_3$ emission in landfill sites. First, it computes surface values by grids using the Digital Elevation Model (DEM). Second, it presents predicted data considering topography and climate by grids. Third, it shows the overlaying analysis of the administrative map including population and odor predictive data. The results could systematically analyze impact areas, and assess residential impact by alternatives. Integration analysis of the air predictive model and GIS as a residential area assessment can support negotiations of public and proponent in EIA.

• The Journal of Society for e-Business Studies
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• v.12 no.2
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• pp.155-194
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• 2007

Currently, Ubiquitous Computing Technology(UCT)-based service scenarios play an important role in estimating the potential of UCT-based service. The purpose of the study is to propose a multidimensional evaluation(ME) methodology for UCT-based service scenarios regarding their possibilities of realization for the future. Our approach contributes to extend service level management in Information Technology Service Management(ITSM) by evaluating the level of a new service in advance. ME consists of three dimensions: technological evaluations, business-oriented evaluations, and user-oriented evaluations. The three types of evaluations are mutually harmonized to check the overall possibility of realization and validity for certain UCT-based service scenarios. Theoretically, ME is developed to overcome the extant evaluation methods for UCT-based service scenarios, which are limited in the number of evaluation criterions. It is also conceived to cope with the limitation of economical evaluation methods (e.g., technological valuation, estimation of financial outcomes such as ROI, ROA, etc. that are difficult to give meaningful results because most of UCT-based services are not fully realized so far. From the practical perspectives, in addition, our approach can be applied to a variety of scenarios due to its domain-independent approach.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.533-536
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• 2007

최근 웹 표준의 준수와 웹 접근성 향상을 위한 노력이 기업체에서 뿐만 아니라 공공기관 등에서도 확산되고 있으며, 필수 요소로 자리매김하고 있는 추세이다. 인터넷을 사용하는 환경은 개인용 컴퓨터의 윈도우 기반에서 인터넷을 사용하는 환경과 시대에서 벗어나고 있다. 학생들의 인터넷 사용 환경도 핸드폰, PDA 등의 모바일 기기를 이용한 다양한 플랫폼으로 확산되고 있는 실정이며, 이에 따라 교육용 홈 페이지에서도 웹 접근성 향상을 위한 노력이 필요한 때이다. 이 논문에서는 한국형 웹 콘텐츠 접근성 지침에 대하여 알아보고, 일선 학교에서 운영하는 교육용 홈 페이지에서 웹 접근성 향상을 위한 방법으로 웹 콘텐츠 접근성 지침에 따른 평가 방법을 도입하는 방안을 제안한다.