• The Journal of the Korean dental association
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• v.54 no.12
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• pp.1045-1054
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• 2016

Purpose : Aim of this study is to describe and compare clinical results and complications epending on the surgical approaches for the mandibular subcondyle fracture Materials and methods : The patients who had been diagnosed as the mandibular subcondyle fracture and underwent open reduction and internal fixation from May 2009 to December 2014 were included. They were divided into two groups depending on the surgical approaches; endoscopically assisted transoral approach and retromandibular approach. Association between the preoperative fracture classification and post-operative results was reviewed depending on the surgical approaches. Results : The number of patients selected in this study was 33. Eighteen patients (male 7, female 11) underwent open reduction and internal fixation via retromandibular approach and fifteen patients (male 12, female 3) underwent open reduction and internal fixation via endoscopically assisted transoral approach. The mean age, follow up period, and operation time were $44.29{\pm}15.19years$, $9.97{\pm}7.82months$, and $161{\pm}89.44minutes$. Post-operative results were all "good" state in the retromandibular approach group regardless of the fracture classification but two patients in the endoscopically assisted transoral approach group underwent re-operation due to "poor" results. The fracture types of two were classified as displacement and lateral override at the same time. There was no statistically significant difference between two groups. Three patients in the retromandibular approach group had experienced facial nerve palsy (17%) temporarily. No one showed malocclusion in this study. There was no significant difference on the complications such as temporomandibular disorder, local infection, and condyle resorption depending on the surgical approaches. Conclusion : In this study, there was no significant difference on the complications between the two groups but retromandibular approach has advantage over endoscopically assisted transoral approach in case of the severely displaced subcondyle fracture.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.4
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• pp.213-220
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• 2017

This study examines the limitations of existing crime mapping that relies mainly on reported crime data, suggests a crime mapping method based on experts' and users' assessments of a neighborhood environment as an alternative approach, and conducts a case study on a real-world site by applying the suggested approach. According to the results of the case analysis, while the areas adjoining arterial roads with heavy pedestrian traffic were shown as high crime risk areas in the crime map based on actual reported crime data, the areas adjoining local roads with low pedestrian traffic were high-risk areas in the crime risk area map based on experts' and residents' evaluations. This study makes a contribution to the field in that it demonstrates the detailed application process of crime risk area mapping according experts' and residents' evaluations, compares the results with those of an existing crime map, and finally shows that the former can function as a complement to the latter.

• IE interfaces
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• v.15 no.4
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• pp.409-425
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• 2002

This case study provides a market analysis methodology for overseas markets by applying statistical tools and the Six Sigma approach. The study suggests a procedure with seven steps to improve brands position in the market. These steps consist of interviewing consumers and floor salesmen of stores, surveying, analysis of correlation between brand position and customers satisfaction, analysis of relationship with companies and customer satisfaction factors, analysis of the customer satisfaction gap between companies, evaluating the importance of customer satisfaction factors, and suggestion for enhancement of brand position. The Six Sigma approach such as "Define", "Measure" and "Analyze" is used in this procedure, which is part of Six Sigma procedure, D-M-A-I-C (Define, Measure, Analyze, Improve, Control). Minitab and SAS are used for the statistical analysis.

• The Journal of Industrial Distribution & Business
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• v.6 no.3
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• pp.9-17
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• 2015

Purpose - The study's aim is to assess performance quality delivered through a performance management system. The case study first measures the effectiveness of the present performance management system of Bhushan Steel Ltd. (BSL), and then secondarily analyzes the employee training impact. Research design, data, and methodology - A case study research approach using a survey was followed. The final sample size was 50, with a simple random sampling technique used. Primary data came from the company itself and the secondary from books, the Internet, journals, etc. Results - BSL employee appraisals are used for many developmental aspects such as competence in the present job, improvements, performance development, and training needs. The results indicate that individual performance can improve if employees perceive the system as more transparent (i.e., not so confidential). Conclusions - Overall, the BSL employees think that the company appraisal system is useful; however, to make it better the company has to improve many aspects including appraisals based on supervisor observations. The company could use a self-appraisal and a 360-appraisal approach to improve such assessments.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.3
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• pp.1-8
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• 2018

Aviation industry is growing rapidly, and this growth is expected to continue. However, aircraft accident rate is still high, and 65 percent of accidents occur during landing phase due to unstable approach. Therefore, this research analyzed causes and countermeasures of unstable approach. In order to derive countermeasures, this study selected P International Airport as an example case. In addition, this research analyzed A airline's FOQA data, regional Standard Operating Procedures, and 5 years of environmental factors to identified correlation of those contributing factors. In conclusion, his research concluded following results. First of all, because of P International Airport's geological features, pilots are required to conduct Circling Approach, and this advanced maneuver increases workload at the final stage of flight. Secondarily, meteorological factors such as crosswind, seasonal rain front, local visibility contributes unstable approach. Lastly, these geological and meteorological factors are interrelated, and this uncommon environment can decrease circumstantial judgement ability of pilots and jeopardize aviation safety. As a consequence, it is recommended to reinforce the Crew Resource Management and Threat & Error Management systems so that pilots can perceive identical safety target.

• Korean Security Journal
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• no.4
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• pp.189-218
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• 2001

Mr. Cho OO, a famous ex-delinquent who has already spent 27 years in prison for his hardened stealing habit and escape, was recently again arrested by Japanese police for housrbreaking in Japan. Every Korean people would have believed that he had abandoned his habit for good, because, since his liberation in 1998 , he showed himself as a man perfectly cured. He became a believer more than ever, married a well-to-do beautiful woman, got a son from her, had a good income from his job as homme security counsellor and from several other occupations, and after all worked a lot for homeless and unfortunate. Now, his case is given as an important subject to approach for criminologists. As well as we are concerned, we thought, to explain his case criminological, it's primarily necessary to skim through the main criminological theories, and that in behalf of this case. After that, we will be able to decide which theory is mostly appropriate to explain his inveterate disease. The one we chose is the social learning theory. But this theory alone won't allow us to understand all aspects of his crime. This is why we will have to turn to several other theories to complete our explanation. But theoretical understanding alone of a criminal case is useless if it cannot suggest a remedy for it. And, we finish our study by making some suggestions on this case.

• IE interfaces
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• v.18 no.4
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• pp.412-417
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• 2005

This paper describes the development of on-line Programmable Logic Controller(PLC) laboratories to teach the detailed operation of a PLC using distance learning approach. The PLC has become a key component to provide intelligence for machines in CIM environment. This study introduces a case study that teaches PLC programming in distance learning environment. The study describes the contents of PLC laboratories and workstation set ups. The study concludes with problems found and proposes the ways to improve the on-line laboratories.

• Smart Structures and Systems
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• v.13 no.3
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• pp.473-500
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• 2014

Tuned mass dampers (TMDs) have been installed in many high-rise buildings, to improve their resiliency under dynamic loads. However, high-rise buildings may experience natural frequency changes under ambient temperature fluctuations, extreme wind loads and relative humidity variations. This makes the design of a TMD challenging and may lead to a detuned scenario, which can reduce significantly the performance. To alleviate this problem, the current paper presents a proposed approach for the design of a robust and efficient TMD. The approach accounts for the uncertain natural frequency, the optimization objective and the input excitation. The study shows that robust design parameters can be different from the optimal parameters. Nevertheless, predetermined optimal parameters are useful to attain design robustness. A case study of a high-rise building is executed. The TMD designed with the proposed approach showed its robustness and effectiveness in reducing the responses of high-rise buildings under multidirectional wind. The case study represents an engineered design that is instructive. The results show that shear buildings may be controlled with less effort than cantilever buildings. Structural control performance in high-rise buildings may depend on the shape of the building, hence the flow patterns, as well as the wind direction angle. To further increase the performance of the robust TMD in one lateral direction, active control using LQG and fuzzy logic controllers was carried out. The performance of the controllers is remarkable in enhancing the response reduction. In addition, the fuzzy logic controller may be more robust than the LQG controller.

• Proceedings of the KSRS Conference
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• v.1
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• pp.243-246
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• 2006

Wavelet approach is regarded as a useful methodology for geo-environment analysis with respect to spatial objects with periodicity and spatial pattern, compared to autocorrelation analysis, Fourier analysis, variogram analysis and so on. However, there are a few case studies for geo-lineament characterization with the actual geo-based information such as remotely sensed imagery and DEM. In this study, wavelet approach in the Uiseung caldera region are carried out to delineate characterization for geolineament spatial pattern. There are high possibilities of the development of radial lineaments from the centre of round crater due to the eruption of a volcano and the subsidence of a crater. We have grasped the directionality of the whole linear structures of the caldera via rose diagram, and then performed wavelet analysis on the profiles of orthogonal directions for main directions of the lineaments. The result of this study is likely to be used as a fundamental data in order to grasp the outline of caldera structure prior to the close estimation

• Design Convergence Study
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• v.16 no.5
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• pp.125-140
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• 2017

This study explores potential capability of a machine learning approach for monitoring urban morphology based on an evident case study. The case study conveys year 2006 investigations on interpreting urban morphology of Boston Main Streets by applying a machine learning approach. From the lesson of the precedent study, in 2016, another field research and interview was conducted to compare changes in urban situation, data commons culture, and technology innovation during the decade. This paper describes open possibilities to advance urban monitoring for morphological changes. Most of all, a multi-participatory data platform enables managing urban data system in real time. Second, collaboration with machines with artificial intelligence can intervene the framework of the urban management system as well as transform it through new demands of innovative industries. Recently, urban regeneration became a dominant urban planning strategy in Korean, therefore, urban monitoring is on demand. It is timely important to correspond to in-situ problems based on empirical research.