• Journal of Chest Surgery
• /
• v.26 no.10
• /
• pp.753-760
• /
• 1993

The CarboMedics valve is a bileaflet prosthesis with excellent hemodynamic characteristics, but the long term surgical experience with this valve, its durability and its biocompatibility are unknown. During a 5 year period from october 1988 to July 1993, 748 prostheses [402 mitral, 261 aortic, 58 tricuspid, 27 pulmonic] were inserted in 552 patients [mean age 40.2 years]. The operative mortality was 6.6% [37/560, 13.2% in age group below 15 years and 5.7% above 15 years]. and the main causes of death were complex congenital malformation and left ventricular failure. Follow up was totaled 1182 patient- years and mean follow up was 28.3 months/patient. No structural failure has been observed. Hemorrhage was the most frequent valve related complication[1.78% / Patient-year]. Embolism occurred at a rate of 0.93% / Patient-year. There were 5 cases of valve thrombosis [0.42% / Patient-year, two fatal]. There occurred 11 late deaths[6 valve related] and 42 valve related complications. Actuarial survival at 5 years is 97.18 0.94% and actuarial complication free survival at 5 years is 89.07 1.54%. In summary, the CarboMedics valve stands for a durable valve substitute, with low valve related complications.

• International Journal of Contents
• /
• v.13 no.4
• /
• pp.29-38
• /
• 2017

The objective of this study was to determine the status of current chapel courses and analyze the necessity of online chapel courses. Students' interest, failure experience, perceived problems, and advantages of current chapel courses were examined. Students' preference, intention of sincerity, and perceived effectiveness of online chapel courses were also determined. Finally, hypothesis tests for the differences of students' interest, failure experience, perceived problems and advantages of current chapel courses, preference, intention of sincerity, and perceived effectiveness of online chapel courses according to gender, school year grade, major of study, and religion were performed. Students' low interest in chapel courses was verified. Even Christian students' interest was below 3 points out of 5-point Likert scale. However, students whose religion was not Christianity felt more coercion and had less interest in chapel courses. They wanted virtualization of chapel courses more. They had more willingness to faithful participation in online chapel courses. This research suggests that virtualization of chapel courses as a solution to chapel resistance is dependent on student's characteristics such as religion, major field of study, and mindset.

• Korean Journal of Culture and Social Issue
• /
• v.11 no.2
• /
• pp.73-108
• /
• 2005

This study examines the failure experience and aspirations for future among Korean adolescents and their parents using indigenous psychological analysis. The first part of this paper reviews the achievement literature that has used indigenous psychological analysis. The second part of this paper provides an empirical analysis of 482 students (primary=117, middle school=88, high school=72, and university=205) and 507 parents of the adolescents (fathers= 236, mothers=271). The open-ended questionnaire developed by Park and Kim (1999) was adopted for the study that asked the respondents to list the most painful experience, the person that was the most responsible for the failure, and the most important reason for the failure. The section on aspirations for the future asked the respondents to list the achievement that they would most likely to succeed, the person that they need assistance from, the type of support they need from the person, and the most important factor that would lead to them to success. The results indicate that for students the most painful failure was related to academic failure and for adults, it was related to family life. The person that was most responsible for the failure was reported by both samples be themselves. As for the most important factor that influenced their failure was a lack of self-regulation, such as a lack of effort and persistence. For the aspiration for future, students listed academic and occupational success and for adults listed harmonious family life as the most important. For social support, the adolescents listed their parents and adults listed their spouse as the person that they need assistance from. As for type of support, they listed emotional support to be the most important. As for the most important factor that would contribute to their success, majority of students and adults listed self-regulation. Based on these results and previous indigenous studies indicate, the following four conclusions could be drawn: (1) the emphasis of self-regulation as the most important reason for their past achievement, the future success and the lack of self-regulation for their failure; (2) the importance of receiving emotional support from family members; (3) the importance of educational aspiration and achievement for providing the basis of economic development; and 4) the importance goal of achieving harmonious family life.

• Journal of Technology Innovation
• /
• v.26 no.3
• /
• pp.69-97
• /
• 2018

This study explored the influence of failure experience of Korean pharmaceutical industries on the innovative activities of corporations from the perspectives of R&D and knowledge search. Previous studies have defined the cause of the failure or studied the reasons for the decline. However, studies analyzing the influence of failure on the innovative activities of corporations are rare. This study set a research period of 10 years for the Korean pharmaceutical industry to conduct a longitudinal analysis of the influence of the influence of failure on innovation activities and the influence of innovation activities on radical innovation. A summary of the research results is as follows. Firstly, failure of corporations induce exploratory innovation activities, and the extent differs greatly from the size of financial slack resource. Secondly, experiences of corporations' failure were not significant from the perspective of knowledge search. Thirdly, the interaction between the corporation's exploratory innovation activities and knowledge search had a positive (+) relationship with radical innovation performance. This study is significant in that it suggested empirical evidence by verifying the positive influence of failure to learning and innovation unlike previous researches viewing failure negatively, and suggested the direction of future studies based on these research results.

• Advanced Composite Materials
• /
• v.18 no.3
• /
• pp.233-249
• /
• 2009

Safe installation and operation of high-pressure composite cylinders for hydrogen storage are of primary concern. It is unavoidable for the cylinders to experience temperature variation and significant thermal input during service. The maximum failure pressure that the cylinder can sustain is affected due to the dependence of composite material properties on temperature and complexity of cylinder design. Most of the analysis reported for high-pressure composite cylinders is based on simplifying assumptions and does not account for complexities like thermo-mechanical behavior and temperature dependent material properties. In the present work, a comprehensive finite element simulation tool for the design of hydrogen storage cylinder system is developed. The structural response of the cylinder is analyzed using laminated shell theory accounting for transverse shear deformation and geometric nonlinearity. A composite failure model is used to evaluate the failure pressure under various thermo-mechanical loadings. A back-propagation neural network (NNk) model is developed to predict the maximum failure pressure using the analysis results. The failure pressures predicted from NNk model are compared with those from test cases. The developed NNk model is capable of predicting the failure pressure for any given loading condition.

• Journal of Venture Innovation
• /
• v.5 no.2
• /
• pp.35-48
• /
• 2022

This study was conducted to analyze the effect on entrepreneurial intention and empirically analyze which factors have the greatest influence. To this end, self-achievement motivation, indirect experience, role model, awareness of entrepreneurs, and fear of business failure were set as independent variables as factors influencing entrepreneurial intention. In order to empirically analyze this, 399 valid samples for the general public were analyzed. SPSS 25.0 was used for statistical analysis. As a result of the empirical analysis of this study, self-achievement motivation, indirect experience, role model, awareness of entrepreneurs, and fear of business failure all had a positive and significant effect on entrepreneurial intention. The results of this study confirmed that self-achievement motivation had the greatest influence among the factors affecting entrepreneurial intention. It is significant in that indirect experiences and role models such as theoretical entrepreneurship lectures, special entrepreneurship lectures, and parents or acquaintances influence entrepreneurial intention.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.8
• /
• pp.1177-1183
• /
• 2013

In this paper, the analysis of inspection period bases on reliability is suggested in the field of traction power system. Even though there are several maintenance models, the most commonly used maintenance assessment has been focused on time based maintenance in real traction power systems. The maintenance intervals are selected on the basis of long-time experience. It ensures high availability and exact planning of staff. Reliability centered maintenance, which evaluates criticality and severity of each failure mode, achieves the operation, maintenance, and cost-effective improvement that will manage the risks of equipment. This paper deals with electrification in railway inspection frequency and applied reliability based inspection frequency instead of constant intervals. The distribution function of failure rate in traction power system belongs to Weibull function. Also, the fault data and the number of installed equipments for electrifications are collected. The failure history is investigated and classified in detail. Though these complicated procedures, it contribute to extend equipment lifetime and to reduce maintenance costs.

• International Journal of Contents
• /
• v.8 no.3
• /
• pp.71-78
• /
• 2012

The emergence of the Internet has provided a new outlet for consumers who experience service failure from products and services, augmenting the traditional options of entry, voice and action. Consumers' negative word of mouth through online (word-of-mouse or eWOM) far exceeds traditional word of mouth (WOM) in respect of its potential effectiveness, speed and spread. This paper tries to figure out the service failure themes in the health care industry by analyzing online word-of-mouse using the critical incidents technique (CIT). Complaint themes in the area of healthcare are identified and analyzed. The results identify that major complaint theme differed according to the site type. Also, the findings indicate that delivery and customer services are critical issues when consumer makes negative WOM.

• Nuclear Engineering and Technology
• /
• v.33 no.6
• /
• pp.596-604
• /
• 2001

This paper quantitatively presents the effects of important factors of the probabilistic safety assessment (PSA) of safety-critical digital systems. The result which is quantified using fault tree analysis methodology shows that these factors remarkably affect the system safety. In this paper we list the factors which should be represented by the model for PSA. Based on the PSA experience, we select three important factors which are expected to dominate the system unavailability. They are the avoidance of common cause failure, the coverage of fault tolerant mechanisms and software failure probability. We Quantitatively demonstrate the effect of these three factors. The broader usage of digital equipment in nuclear power plants gives rise to the safety problems. Even though conventional PSA methods are immature for applying to microprocessor-based digital systems, practical needs force us to apply it because the result of PSA plays an important role in proving the safety of a designed system. We expect the analysis result to provide valuable feedback to the designers of digital safety- critical systems.

• Journal of Technology Innovation
• /
• v.15 no.1
• /
• pp.1-26
• /
• 2007

This study's purpose is to promote the development of CT industry by analizing the causal relationship between technology factor and commercialization of Tech. in CT SMEs and Ventures. The result is that Only technology experience accumulation among technical factors(technology develpoment cost, technology experience accumulation, technology concentration, technical expertise) has a significant effect on commercialization success or failure and non-technical factors have not a significant effect on.