• Journal of the Korean Society for Precision Engineering
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• v.13 no.9
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• pp.114-129
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• 1996

This paper describes the whole development phase for the underwater vehicle actuating system with high hydroload torque disturbance. This includes requirement analysis, system modeling, control algorithm design, real time implementation, test and performance evaluations. As for driving control algorithms, fuzzy logic, variable structure and PD(Proportional-Differential) algorithm were designed and implemented on board controller using a single chip microprocessor. Intel 8797. And test and performance evaluation is carried out both single test and wystem integration test. We could confirm the basic performance of actuating system through the single test and gereral developing work of any actuating systems was finished with a single performance test of actuating system without system integration test. But, we suggested that system integration test be needed. System integration test is carried out using G/C HILS(Guidance and Control Hardware-In-the -Loop Simulation) which is constituted flight motion simulator, load simulator, real time host computer and the related subsystems such as inertial navigation system, power supply system and Guidance and Control Computer etc.. The most important practical contribution of this paper is that full system characteristics such as minimal control effort, enhancement of guidance and autopilot performance by the actuating system using G/C HILS technique are investigated. Through full running G/C HILS, in spite of the passing to single tests, some control algorithm resulted in failure as to stability of full system and system time frame.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.71-79
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• 2010

Thanks to the great development of technology in radiation, we are now able to reduce radiation exposure to the patients, and the radiographer and expenses in medical sector. We are also trying to produce ideal images which maintain useful information. These kinds of effort are increasing over the world. For that reason, we should get images which include necessary data of patients. Then it also can help to reduce radiation exposure to the patients. Therefore, we need to know the problems that cause a falling off in image's quality and check on generator in case of their electronic and mechanical errors. And moreover, we should anticipate the possibility of devices errors and prevent them with regular quality control. This investigation was conducted in medical institutions, institute of educations and hospitals. They are all in Seongnam-City. We used PMX-III, kVp meter to implement kVp test, mR / mAs output test, light fiel / beam alignment test, Reproducibility of exposure dose, half value layer test, reproducibility of exposure time test. in the case of hospitals, they perceive the importance of regular quality control and organize the regular quality control team so they can be satisfied with the error standard in most experiments. On the other hand, when it comes to medical institutions and institute of educations, they perceive the importance of regular quality control less than hospitals do. Radiographer need to understand the importance of regular quality control and practice it so they can get the fine ideal image with the lower dose to the patient.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.63-72
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• 2013

Recent trends in rail industry can be characterized by the multifunctionality and very high-speed modes of operations. In particular, the adoption of the unmaned or operatorless operations has been getting increased attention in which case ensuring systems safety is crucial. On the other hand, according to the result of analyzing rail accidents, the human/operator errors have turned out to be one of the key causes of the accidents. Therefore, the effort of improving the work environment of locomotive cabs is quite necessary in order to decrease the accidents. The objective of this paper is studying on how to incorporate the factors related to the train operators in the design of the locomotive cabs and also on how to evaluate the design results obtained, which is subsequently reflected in the generation of the test and evaluation procedure. The approach taken is based on systems engineering, yielding the procedure document as a result. The results obtained in the paper can be useful in confirming the design of locomotive cabs utilizing the domestic human/operator measure. Also, the way of achieving the objectives can be utilized to cover the expanded rail systems development with appropriate design activities added.

• Journal of Digital Contents Society
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• v.9 no.1
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• pp.139-147
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• 2008

It is difficult to prevent and solve the contrary function of informationized society by a coercive or physical way. It is believed that a systematic education, teachers, experts, parents and students of schools are to be united as one to put every effort on preventing the contrary function of informationized society. In this study, ICT ethics behaviour test system has been designed and implemented with the aim of setting up an appropriate sense of values and cultivating ICT ethics index of juveniles. ICT ethics behaviour test system developed is to meet the contrary function of informationized society actively so the system should prevent the negative phenomenon derived from it. And it is expected to help the system build up the ability of keeping and developing the primary function of informationized society.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1745-1754
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• 2015

This study aimed to analyze the relationship between sea temperatures and anchovy catch of Anchovy drag net fishery using annual time series data from 1970 to 2013. In the analysis, time series data on variables (CPUE, sea surface temperature, and 10m temperature) were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation among variables was found from a cointegration test. From an exclusion test, a 10m temperature would not have relations with CPUE and sea surface temperature. The result of regression analysis on sea surface temperature and anchovy catch indicated that the sea surface temperature would have positive impacts on the anchovy catch. It means that when the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch of anchovy was predicted to increase. More specifically, the result showed that when 1% of sea surface temperature increases, CPUE would be increased by 2.81%.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.318-321
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• 2007

Since human listening is very sensitive to sound, a subjective index of a sound quality is required. Therefore, in the analysis for each situation, the sound evaluation is composed with sound quality factor. Many researchers spends their effort to make a more reliable and more accurate of sound in term of sound quality index for various system noise. The previous methods to evaluation of the SQ about vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of the subjective SQ values by neural network. But these are so depended on jury test very much that they result in many difficulties. So, to reduce jury test weight, we suggested a new method using Mahalanobis distance for SQ evaluation. Threrefore, in this study Mahalanobis distance for the vehicle interior noise was derived using the objective SQ except jury test. Finnaly, the results of the SQ evaluation was analyzed discrimination between reference and abnormal group.

• Annual Conference of KIPS
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• 2017.04a
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• pp.618-620
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• 2017

Currently, IoT mobile applications are growing fast in number and complexity. As a result, the applications quality issue became crucial, hence to ensure their quality a proper testing is highly required. Testing such mobile applications is always tedious, time-consuming and expensive. To cope with these issues, we propose a testing approach using activity diagram with data flow information. The main functionality of IoT applications is exposing the meaningful data obtained from the sensors to the users by doing a lot of analysis, comparison, and computation. Therefore, our focus is on identifying and selecting the most appropriate paths at which calculation is taking place and the paths at which predicate exists. In our case study, we have used a real-world IoT mobile application and identified a total of ten test paths with two predicate uses and two computation uses through an example. With applying only this four critical paths, we can adequately test the application's core functionalities while significantly reduce the testing effort and cost.

• Korea Journal of Hospital Management
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• v.10 no.3
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• pp.1-24
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• 2005

This study purports to investigate the determinants of individual personnel rating of the employees at a university hospital in Seoul, Korea. The sample used in this study consisted of 63 nurses, 41 para-medical staff (Clinical Pathologist, and Radiologist), and 67 administrative staff. Independent variables of the study included the achievement level of the selection test (English, major subject, and interview), post-entrance development factors (education and training, career development, supervisory support, co-worker support, and organizational support), and demographic characteristics. Data for the achievement level of the entrance exam and years for the first promotion were collected from the administrative records of the study hospital, while data for the post-entrance development factors were collected from the survey with self-administered questionnaires using 5-point Likert Scale during June 10-25, 2003. Collected data were analyzed using hierarchical multiple regression. The results of the study showed that achievement level of the interview and English exam at the selection test, education and training, organizational support, and supervisory support while working at the hospital, and length of duration (below 8 years) and educational background (4-year college graduates) among demographic variables had significant positive effects on the personnel rating. The results of the study imply that hospital administrators should make an effort to improve the validity of the selection test, and to motivate the employees to receive more education and training.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.49-52
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• 2006

should be in English, A make out an economical, reliable and easy to adoptable instrument in turbine discharge measurement was restricted from lots of it's foundational condition. Not with standing the brilliant progress in new technology of these day, useful instrument for flow measurement in turbine is still ongoing. Nowaday, the increasing importance of renewable energy makes it more important that the measuring turbine efficiency as a decision making index of old turbines' replacement. In Turbine performance diagnosis, Kwater(Korea Water Corporation) got an enough ability and decent reputation for who has invested lots of time and effort for buildup and development. In Korea as a public corporation who should take a crucial roll in Turbine business, Kwater has introduced some developed new technology for other domestic concerned one. With this writing, I'd like to introduce ASFM system as a newly developed instrument that can cope with lots restriction in discharge measurement in turbine. Kwater adopted the system in 2005, and performed 2 times of trial test. The test result was good enough to use the system as a reference test method.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1193-1198
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• 2007

The total number of passengers for Line $1{\sim}4$ operated by Seoul Metro among subways that act as foot of Seoul residents was 1.43116 billion passengers in 2006 and average of 3.921 million passengers per day. The results of analysis on safety accidents that occurred recently in subways show that various complaints on subways were reduced through the expansion of safety related facilities and training but accidents caused by negligent handling by employees including engineers are increasing on the contrary. At present time where various man-made accidents break out such as wrong handling and habits of engineers in charge of driving trains and momentary mistakes, there needs effort for active management and improvement to prevent and minimize accidents. Therefore, this study has drawn out problems through surveys on aptitude test system to engineers and compared with case studies in overseas. Thus, it attempted to minimize safety accidents in subways, and derived methods for improving safety management by focusing on improving the current aptitude test system for nurturing engineers suitable to handle railway driving in the future.