• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.61-68
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• 2010

Purpose: This article attempted to determine the factors affecting the preload and screw loosening. Methods: Available clinical studies from 1981 to 2008 from the PUBMED that presented screw loosening data and review articles regarding screw joint stability were evaluated. Eleven studies dealing the biomechanical principles of the screw mechanics were reviewed. Moreover, the results of our data were included. Results: The frequency of screw loosening was consequently reduced due to the advancement in torque tightening with torque wrench, screw material, coating technique for reducing the frictional force, and thread design, etc. If preload in the screw falls below a critical level, joint stability may be compromised, and the screw joint may fail clinically. The types of fatigue failure of screw were divided to adhesive wear, plastic deformation, and screw fracture. Conclusion: An optimum preload is essential to the success of the implant-abutment complex. To maintain optimum preload, using a torque wrench and re-tightening at recall time were needed.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.3
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• pp.171-185
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• 2000

The treatment objectives of the complete oral rehabilitation are : (1) comfortably functioning temporomandibular joints and stomatognathic musculature, (2) adherence to the basic principle of occlusion advocated by Schuyler, (3) anterior guidance that is in harmony with the envelope of function, (4) restorations that will not violate the patient's neutral zone. There may be many roads to achieving these objectives, but they all convey varing degrees of stress and strain on the dentist and patient. There are no "easy" cases of oral rehabilitation. Time must be taken to think, time must be taken to plan, and time must be taken to perform, since time is the critical element in both success and failure. Moreover, a systematized and integrated approach will lead to a prognosis that is favorable and predictable. This approach facilitates development of optimum oral function, comfort, and esthetics, resulting in a satisfied patient. Such a systematized approach consists of four logical phase : (1) patient evaluation, (2) comprehensive analysis and treatment planning, (3) integrated and systematic reconstruction, and (4) postoperative maintenance. Firstly, we must evaluate the mandibular position. The results of a repetitive, unstrained, nondeflective, nonmanipulated mandibular closure into complete maxillomandibular intercuspation is not so much a "centric" occlusion as it is a stable occlusion. Accordingly, we ought to concern ourselves less with mandibular centricity and more with mandibular stability, which actually is the relationship we are trying to establish. The key to this stability is intercuspal precision. Once neuromuscular passivity has been achieved during an appropriate period of occlusal adjustment and provisionalization, subsequent intercuspal precision becomes the controlling factors in maintaining a stable mandibular position. Secondly, we must evaluate the planned vertical dimension of occlusion in relationship to what may now be an altered(generally diminished), and avoid the hazard of using such an abnormal position to indicate ultimate occlusal contacting points. There are no hard and fast rules to follow, no formulas, and no precise ratios between the vertical dimension of occlusion. Like centric relation, it is an area, not a point.

• Journal of Elementary Mathematics Education in Korea
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• v.23 no.1
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• pp.59-74
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• 2019

According to previous studies, it shows that the metacognitive ability that makes the positive element of the problem solver positively affects the problem-solving process of mathematics. In order to accurately grasp causality, this study investigates the specific characteristics of the meta-affect factor in the process of problem-solving. To do this, we analyzed the types and frequency of data collected from collaborative problem-solving situations composed of 4th~6th grade mathematically gifted children in small group of two. As a result, it can be seen that the type of meta-affect in the problem-solving process of mathematically gifted children is related to the correctness rate of the problem. First, regardless of the success or failure of the problem-solving, the meta-affect appeared relatively frequently in the meta-affect types in which the cognitive factors related to the context of problem-solving appeared first, and acted as the meta-functional type of the evaluation and attitude. Especially, in the case of successful problem-solving of mathematically gifted children, meta-affect showed a very active function as meta-functional type of evaluation.

• Journal of Korea Entertainment Industry Association
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• v.15 no.4
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• pp.359-367
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• 2021

This study tried to examine the factors that affect the entrepreneurial intentions in the field of culture and tourism industry. Through this, it was attempted to present strategic implications for start-up plans to prospective entrepreneurs in the cultural tourism industry. As a result of the study, the following implications were drawn. First, prospective entrepreneurs in the field of culture and tourism industry need to analyze the start-up items they want to start and systematically design a start-up plan based on market research. Also, by analyzing various start-up cases, it is necessary to secure various prior experiences of failure and success. Second, prospective entrepreneurs in the field of culture and tourism industry will need to increase their interest in starting a business by completing various entrepreneurship education conducted by more diverse institutions and schools than now, and they will have to increase the sense of achievement and willpower that can appear in education. In addition, by making efforts to create human relationships through various entrepreneurship education, efforts should be made to show the utilization of human networks and information sharing when starting a business. Lastly, prospective entrepreneurs in the field of culture and tourism industry should visit startup-related institutions and receive education and advice from experts in order to acquire various information. In addition, efforts should be made to provide more diverse start-up support by obtaining information on start-ups implemented by the state.

• Journal of the Korea Institute of Building Construction
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• v.23 no.3
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• pp.305-313
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• 2023

With an increasing interest in the commercialization of research results in the present societal climate, especially in the construction industry, preliminary product analysis plays a critical role when introducing a new product to the market. It significantly influences the product's success or failure. In this context, this study aims to investigate the utility of Importance-Performance Analysis (IPA) as a management strategy tool for preliminary analysis in the commercialization of new architectural technologies. The study specifically assesses a smart ball product engineered for pipeline inspection. The evaluation is carried out based on product quality, convenience, and usability categories. Seventeen factors are recognized as sub-items, and a survey is conducted among relevant experts and consumer groups. From the survey, four key items are chosen: "Keep up the good work," "Concentrate here," "Low priority," and "Possible overkill." Suitable strategic measures are derived for each item. By conducting a correlation analysis between product importance and performance, this study offers a method to establish priority directions for future development. This analysis assists in identifying areas that necessitate improvement or additional focus to increase the product's commercial potential. On the whole, this study contributes to understanding and applying Importance-Performance Analysis as a valuable tool in the preliminary analysis and commercialization of novel technologies in the field of architecture.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.635-647
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• 2006

Korean construction companies first advanced to the international markets in 1960's and so far have brought more than 4,900 projects which account for 193 billion dollars approximately. With the large increase of national employment and income being followed by the achievement, Korea's construction industry has made an enormous contribution to the improvement of domestic economy for the last 40 years. However, recently the increased risk in international markets as well as the sharpening competition with foreign companies promising in terms of advanced technologies and low labor cost have been driving Korean construction away from the market shares. According to ENR (Engineering News Record, 1994~2003), it is revealed that 15.1% of top 225 global contractors are suffering from loss in international construction markets. This phenomenon is largely due to the highly uncertain characteristics of international projects, which are inherently exposed to various and complicated risky situations. Furthermore, especially for Korean construction companies, it is often the case that the failure in an international construction project cannot be offset by even a sufficient number of successful domestic achievements. Therefore, not only the selective screening among the nominated projects which have strong possibility of collapse but the systematic strategies for controlling potential risk factors are also considered indispensable in international construction portfolio management. The purpose of this study is to first analyze the causal relationships of the profit-influencing variables and the project success, and develop the profitability forecasting model in international construction projects.

• Journal of the Korean Society of Radiology
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• v.82 no.3
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• pp.589-599
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• 2021

Purpose To analyze the success and complication rates and factors associated with technical failure of the ultrasound (US)-guided percutaneous thrombin injection of femoral artery pseudoaneurysms caused by vascular access. Materials and Methods Records of 30 patients with post-catheterization femoral artery pseudoaneurysms who had been treated with US-guided percutaneous thrombin injections in the department of radiology between March 2009 and June 2019 were retrospectively analyzed. The lesion was diagnosed based on US or contrast-enhanced CT. The characteristics of the patients and their lesions were analyzed. Results The mean patient age was 67.8 years. The mean diameter of the pseudoaneurysmal sac was 20.88 mm (5-40 mm). Twenty patients (66.6%) obtained complete thrombosis after the primary injection, while 10 patients (33.3%) obtained partial thrombosis. The number of patients with a low platelet count (< 130 k/µL) was significantly higher in the partial thrombosis group than in the complete thrombosis group (p = 0.02). No substantial procedure-related complications were found in any patient. Conclusion The US-guided percutaneous thrombin injection is considered an initial treatment option for pseudoaneurysms caused by vascular access because of its safety and efficacy.

• Journal of Distribution Research
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• v.17 no.5
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• pp.129-146
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• 2012

Recently, Korea became the 7th country in the world which has got into the 20-50 clubs that means the population is 50 million and per capital income is $20,000. From the view point of the retail industry, it suggests that Korea should have its own self-sufficient market by itself. With abundant labor and increased disposable income, it made the consumer's needs change. Responding to the change, retail and F&B oriented retail malls are now starting to add culture, art and entertainment facilities in the configurations. Such complexity and variety of the shopping malls became trendy and many shopping complexes are scheduled to open in the near future across the country. Due to above reasons, it became the common trend to develop shopping complex all over the cities now. However, the history of the shopping mall in Korea is much shorter than developed countries such as America and Japan. Thereby, a lot of problems, trial and error have occurred in the process of developing and operating them. If development of shopping complex failed, it would return lots of damages to the stakeholder. Therefore, the corporations should develop the mall properly and government might support positively. In this study, we would like to propose on how all the mall should be developed and well managed and what are the ways for the vitalizing factors of the shopping complex after benchmarking other shopping mall cases. Through the case study, we realized that the most crucial factors for vitalizing shopping complex were interior design, merchandising and how well they operate the mall. In case of the failed shopping mall, developers sell each store to individual proprietors and never take care of them after they get the profit, which make it hard to have integrated marketing strategies. That causes the overall slump of the mall. Corporations developing the mall should operate it as well, so that it could be possible to make the mall consistently well managed and promoted. There is a certificate for the shopping mall expert in The States and Japan. However, we do not have this kind of certificate. In fact, if we judge the capability of a person who is involved in the shopping mall industry, we usually measure how many years they stick to the same industries and that is not equally the same as their competence. Therefore it is necessary to organize "Shopping Mall Associate" and introduce shopping mall license for the mall expert. Due to retail trends, we can easily see a lot of shopping facilities all over the cities but not every mall is able to be successful. We think it's essential that the government should certify the malls which are qualified for the design, merchandising and proficiency of the operation. For the qualified mall, the government could confer a benefit on the company such as reducing corporation taxes. In multi-complex shopping mall it is possible to make convenient for customers. However, if a mall failed to succeed, it would be disaster. To build a shopping complex, developers should invest huge money even take out loan so that many people would be connected to the project, which may affect their whole financial conditions. In addition, only qualified corporation should develop and operate shopping complex and the government must support and aid the developers in order to make a better shopping environment in which customers might be happy during their shopping experience.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.151-163
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• 2015

This study aims to clarify factors having effect on the turnover and entrepreneurial intention of financial institution workers. Particularly, this study analyzed the effect of job satisfaction, job insecurity, retirement expectation and retirement preparation activities. As research subjects, this study selected financial institution workers residing in Seoul and the capital area and used a total of 508 samples as analysis data. This study analyzed job satisfaction, job insecurity, retirement expectation and retirement preparation activities as factors having effect on the turnover and entrepreneurial intention of financial institution workers. The research results can be summarized as follows; Firstly, all the factors of job satisfaction had negative (-) effect on their turnover intention, and compensation satisfaction and interpersonal relation satisfaction also had negative (-) effect on their entrepreneurial intention. Secondly, since job insecurity had positive (+) effect on their turnover intention and entrepreneurial intentions, the more insecure their jobs became, the more their turnover and entrepreneurial intention increased. Thirdly, in the retirement expectation, forced frustration and continuation had positive (+) effect on their turnover intention, and forced frustration, new start and continuation also had positive (+) effect on their entrepreneurial intention. Fourthly, in the retirement preparation activity, entrepreneurial preparation, social preparation and physical preparation of retirement preparation activity had positive (+) effect on their turnover intention, but economical preparation had negative (-) effect on their turnover intention, while entrepreneurial preparation had positive (+) effect on their entrepreneurial intention. In other words, as they prepare business start-up more for retirement, their turnover and entrepreneurial intentions increase more. Although they receive higher wages than other workers in different job fields as financial institution workers, they showed significant results about turnover and entrepreneurial intentions, which indicates that job satisfaction, job insecurity, retirement expectation and preparation activities function as important variables in the relation with their turnover and entrepreneurial intentions. Such research results imply that it is necessary to develop various educational programs and turnover and business start-up support programs so that financial institution workers may have better understanding of both success and failure cases when they actually work on business start-ups.

• Tuberculosis and Respiratory Diseases
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• v.60 no.1
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• pp.65-71
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• 2006

Background : Hemoptysis, when massive and untreated, has a mortality rate of over 50 percents, is considered as one of most dreaded of all respiratory emergencies and can have a variety of underlying causes. Bronchial artery embolization (BAE) has become an established procedure in the management of massive and recurrent hemoptysis, and its efficacy is widely documented thereafter by number of articles. However, the long-term success rate of BAE is known to be unfavorable. Risk factors influencing that control failure are inevitably needed. Materials and methods : Seventy-five patients underwent bronchial artery embolization due to massive hemoptysis in Severance Hospital from Jan. 2000 to Jan. 2005. Nine patients' data were not available and could not be contacted with. Finally 66 patients' (48 males, 18 females) medical records were analyzed retrospectively during a mean follow up period of 20.4 months (ranging from 1 month to 54 months). Results : Among 66 patients whose data were available, 23(34.9%) patients had recurrent major hemoptysis. Patients' age, sex, underlying disease, previous intervention history, and number of feeding vessels had no statistical validity as risk factors of recurred major hemoptysis. But bilaterality of lesion, amount of hemoptysis, and pleural thickening were revealed as meaningful factors for predicting relapse (p = 0.008, 0.018, and 0.001, respectively). Conclusion : According to our series, patients presenting with larger amount of hemoptysis, pleural thickening of chest radiography and bilateral lesion are associated with increased risk of major hemoptysis in patients treated with BAE.