• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.1
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• pp.13-18
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• 2023

Objective: Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke secondary to large vessel occlusion. However, recanalization failure rates of interventions were about 20% in literature studies. We report our experience of unsuccessful MT with a focus on technical reasons. Methods: From December 2010 to June 2021, six hundred eight patients with acute ischemic stroke due to large artery occlusion received MT using a stent retriever with or without an aspiration catheter in our institution. We divided the reasons for failure into six categories. We analyzed the reasons for failure by dividing our experience time into 3 periods. Results: A total of 608 cases of thrombectomy for large vessel occlusion were identified in the study period. The successful recanalization rate was 90.4%. In most of the cases (20/57, 35%), the thrombus persisted despite several passes, and the second most common cause was termination of the procedure even after partial recanalization (10/57, 18%). Similar proportions of in-stent occlusion, distal embolization, and termination due to vessel rupture were observed. On analysis of three periods, the successful recanalization rate improved over time. Conclusions: MT fails due to various reasons, and intracranial artery stenosis is the main cause of MT failure. With the development of rescue techniques, the failure rate has gradually decreased. Further development of new devices and techniques could improve the recanalization rates.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.48-52
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• 2002

The fault analysis of the CNC machine tool which is controlled sequentially by PLC is generally based on ladder diagram. When machine tool has faults, it takes a lot of operator's experiences and times to identify logical relationship because ladder diagram is a step structured language. Therefore the technologies of finding out fault reasons automatically is necessary. In this paper, the SFG(Switching Function Generator) system is developed to analysis fault reasons correctly. The SF(Switching Function) and SSF(Step Switching Function) generated from SFG based on ladder diagram are experimented to identify the performance of SFG.

• The Korean Journal of Community Living Science
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• v.19 no.4
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• pp.581-595
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• 2008

This study attempts to provide the main reasons and decision-making processes for marriage migration from a Vietnamese' perspective. For this purpose, in-depth interviews were conducted in Vietnam. Interviewees are those who got married to foreigners but are waiting for visas and parents whose daughters are marriage migrants. According to 23 interviewees, the main reasons of marriage migration are as follows: individual aspiration, sacrifice for others, and the circumstantial effects or love. Individual aspiration, in particular, leads to an active pursuit of international marriage. Parental involvement in the decision-making process is rarely found. Decision seems to be wholly made by the female migrant herself based on an individualistic orientation.

• Education of Primary School Mathematics
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• v.2 no.2
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• pp.75-83
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• 1998

The present study investigated why students do not like math using deep-level interview method. The reasons of why students dislike math were classified into three： socio-cultural, and individual factors, and math itself. Socio-cultural factors include the environments where students are reared, family, and school culture. Individual factors mean competitive disposition, preconception of math, active disposition, and conflicts with friends or teachers. Finally, students seem to dislike math because math itself is a difficult subject. In addition, textbook and instruction are also difficult, or they are lack of fundamental math knowledge. There may be other reasons of why students do not like math subject. In spite of those reasons, there should be some efforts to analyze why students dislike math and to help the students have interests in math.

• Korean Journal of Health Education and Promotion
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• v.28 no.5
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• pp.73-82
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• 2011

Objectives: This study is to gain an understanding of the characteristics of suicides committed by university students in Korea by assessing news reports. Methods: A total of 97 news reports on university student suicides on daily newspapers and TV newscasts from 2000 to 2011 are included in this study. Analyses were performed on sociodemographic characteristics of suicided university students and temporal and other characteristics of the suicides. Results: Suicide rate was higher among males than females. The most frequently used method of suicide was jumping off while the most common place was the students’ residence. Issues related to academic and financial problems topped as the reasons for suicide. There were no differences in the reasons for committing suicide by school year and enrollment, but the location and season of committing suicide differed by reasons for suicide. Conclusions: Implication of this study, discussion on the results and suggestions for suicide prevention are discussed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.204-205
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• 2013

The rational Management of the school facilities will be able to minimize the waste of budgets, enhance total values of facilities. The purpose of this study is to propose promotion plans of the private infrastructure investment in the school facilities not only for contemplating obstacle reasons of BTL projects, but also for gripping contents about process of BTL projects. To achieve these objectives, this study 1)analyzes the major trend about private infrastructure investment, and 2)suggest extended suggestions for minimizing problems in the process of BTL projects in school facilities.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.1
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• pp.119-128
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• 2015

The role and importance of entrepreneurship is fast becoming recognized with the topic of creative economy in Korea. Especially, young generations having difficulties of finding a job choose to be an entrepreneur as a part of their career choice due to the changes in social awareness about entrepreneurship and the increase of entrepreneurship education opportunity. It is needed to approach with the analysis of young people's career choice reasons in order to provide effective entrepreneurship education to those who has the choice of career ahead. Each student has different desire to entrepreneurship lecture and education with the basis of their own motivation and goal of career choice reasons. The objective of this study is to examine career choice reasons with 1,651 science and engineering field students in universities to determine the sustainable needs of entrepreneurship education. As a result of the analysis, there is significant relationship between the satisfaction of entrepreneurship education and the intrinsic factors such as self-realization, innovativeness, role-model and independence. In addition, the satisfaction of entrepreneurship education is significantly related to the sustainable desire of entrepreneurship education. In other words, it is needed to enhance intrinsic value of the students' career choice reasons for sustainable entrepreneurship education due to successful start-ups requiring to have information and understanding process of business which comes from continuous entrepreneurship education.

• Korea journal of population studies
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• v.31 no.3
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• pp.159-178
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• 2008

The main purpose of this paper is to examine selectivity and rasons for move of internal migrants in Korea. There have only been a few studies available on the issues of selectivity and reasons for move of internal migration in Korea, mainly due to the lack of appropriate data. The main source of data for this analysis come from the raw data set of the 1997 Special Migration Survey conducted by the National Statistical Office. Analysis of selectivity of those who moved across the provincial boundary revealed that females, young adults, singles in their marital status and more educated are more likely to move. Among various reasons for move, employment related reason is the most important for all migration streams. But with different migration streams, diverse patterns are emerged. For those who moved into the Capital Region, employment related reason is outstanding. But those who moved out from the Capital Region, moved for employment as well as family related reasons. For movement within the Capital Region, housing related reason is equally important together with employment and family reason. The analysis also found that among individual attributes, age and marital status affect most significantly to the reasons for move. Education level and housing ownership are also important for explaining for variations in reasons for move.

• 한국노년학
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• v.36 no.4
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• pp.1125-1139
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• 2016

The current study examines whether retirement changes health behaviors and how the effect differs by reasons for retirement. This study conducts fixed-effects logistic regression analyses, using data from the Korean Longitudinal Study of Aging (KLoSA) over the period 2006 through 2014. Results indicates that retirees are more likely to participate in regular exercise compared to their employed counterparts. Retirement is positively associated with participation in regular exercise regardless of reasons for retirement. The odds of being engaged in smoking among retirees are 50% less relative to those for employees. However, analyses by reasons for retirement reveal that only participants who retired for health problems or reaching retirement age are less likely to smoke cigarettes compared to employed participants. Retirees show significantly lower odds in drinking compared to employees. Yet, further analyses present that only individuals who retired due to health problems are less likely to drink alcohol. Overall, these results suggest that retirement may provide opportunities for positive changes in health behaviors. The present study imply that individuals who retired due to health problems benefits most from retirement in terms of health behaviors compared to retirees who retired for other reasons.

• Asia-Pacific Journal of Business
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• v.4 no.1
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• pp.31-42
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• 2013

This study aims at discovering the reasons why some customers do not want a relationship. In line with this observation, this paper explores customers' future relationship intentions according to the reasons identified. Based upon a qualitative methodology by way of in depth interviews, we have identified seven factors (e.g., passive loyalty, negative experience, relevance, negative indifference, positive indifference, and emotional value) that lead a consumer not wanting to maintain an ongoing relationship with a company. In Study 2, the author attempts to reveal the effects of each factor over time. The findings show that psychological motivations are useful in improving CRM performance.