• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.277-280
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• 2002

With significant development of power electronics technology, the proliferation of nonlinear loads such as static power converters has deteriorated power quality in power transmission and distribution systems. Notably, voltage harmonics resulting from current harmonics produced by the nonlinear loads have become a serious problem in many countries. There are already a lot of PV power generation systems installed in building systems whose harmonics are the worst object for distribution systems as a utility interactive system and also it tends to spread out continuously. In this paper, the authors propose a multy-function inverter control strategy which puts a shunt active filter function to the power inverter of the PV power generation system established on a building system. The effectiveness of the proposed system is demonstrated through the simulation of hypothetical power system using PSCAD/EMTDC.

• Journal of Engineering Education Research
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• v.19 no.3
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• pp.44-53
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• 2016

In the engineering students, MSC is the most important basic areas in education. Also, the calculus is a main subject in the MSC. So calculus has been operating the annual number of courses at the university. We introduced the concept of joint control ; the joint syllabus, test and assessment. In harsh conditions to maintain joint control system of the calculus, we built a computer-aided-system to manage web-based result processing system. In this paper, we discussed the necessity and effectiveness of joint control system for calculus.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.62-66
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• 2003

In recent, the importance and necessity of some studies on reliability evaluation of grid comes from the recent black-out accidents occurred in the world. The quantity evaluation of transmission system reliability is very important under competitive electricity environment. The reason is that the successful operation of electric power under the deregulated electricity market depends on transmission system reliability management. This paper introduces features and operation modes of the Transmission Reliability Evaluation for Large-Scale Systems(TRELSS) Version 5_1, a program made in EPRI, for assessing reliability indices of composite power system. The package accesses not only bulk but also buses indices for reliability evaluation of composite powers system. The characteristics of the TRELSS program are illustrated by the case studies using the IEEE 25buses system.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.600-601
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• 2007

When the system is larger then the past we need estimation for the customer and continuous maintenance for that. For example like kind of EMS which is the system manage huge information we wants to add and change the extra module. In this operation the first interesting is compatible with the existing system. This is connected with reliance. If you wanted to modify the system under non-standardization we have to pay much money and human resource. Thus in this paper we will mention that the improvement of system structure and necessity of adaption for standardization.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1091-1096
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• 2011

The main factors of radar signals used in electronic warfare are Radio Frequency(RF), Pulse Repetition Interval(PRI), Pulse Width(PW), Scan Parameter(SP) and so on. This radar signals may have some important information for the electronic warfare. So, there is a necessity for making a threat database to decide whether the radar signal is a threat or not. When the electronic support system collects some threat radar signals, it needs the search band to control the receivers and filter banks of the system. In this paper we propose search band implementation considering the type and center frequency of the receivers of the electronic support system.

• Journal of Navigation and Port Research
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• v.31 no.4
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• pp.289-293
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• 2007

In this paper, new application of adaptive neural network to design a ship's Rudder-Roll Damping(RRD) control system is presented Firstly, the ANNAI neural network controller is presented. Secondly, new RRD control system using this neural network approach is developed. It uses two neural network controllers for heading control and roll damping control separately. Finally, Computer simulation of this RRD control system is carried out to compare with a linear quadratic optimal RRD control system; discussions and conclusions are provided. The simulation results show the feasibility of using ANNAI controller for RRD. Also, the necessity of mathematical ship model in designing RRD control system is removed by using NN control technique.

• International journal of advanced smart convergence
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• v.9 no.4
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• pp.120-123
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• 2020

The surveillance system to prevent crime and accidents in advance has become a necessity, not an option in real life. Not only public institutions but also individuals are installing surveillance cameras to protect their property and privacy. However, since the installed surveillance camera cannot be monitored for 24 hours, the focus is on the technology that tracks the video after an accident occurs rather than prevention. In this paper, we propose a system model that monitors abnormal behaviors that may cause crimes through real-time video, and when a specific behavior occurs, the surveillance system automatically detects it and responds immediately through an alarm. We are a model that analyzes real-time images from surveillance cameras and uses I3D models from analysis servers to analyze abnormal behavior and deliver notifications to web servers and then to clients. If the system is implemented with the proposed model, immediate response can be expected when a crime occurs.

• Journal of Auto-vehicle Safety Association
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• v.15 no.1
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• pp.63-68
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• 2023

A study on the need for a safety system using driver's biometric information, vehicle automatic emergency braking system, and the e-call system that in the event of an unexpected situation such as loss of driving ability due to sudden physical abnormality of elderly drivers and drivers with health problems, and the improvement of laws for the spread of this system were studied.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.14-21
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• 2006

The purpose of this study was to investigate the necessity for the extension of education and the desirable educational period of department of food and nutrition in junior college. Questionnaire was answered by the students, professors, dietitians, and the graduates. The result is summarized as follows: 52.1% of the subjects recognized that 2 year-period of education is too short, and professor group felt significantly shorter than any other groups. Both groups of professors(45.7%) and dietitians(43.5%) had more significantly recognized the necessity for the extended period of education than the groups of students(23.0%) and the graduates(21.5%) As the causes of the necessity for the extended period of education, 48.6% of the subjects answered 2 year-period of education is too short to study and practice on the major, and professor group highly recognized that the students need more time to study and practice for the major than time to prepare for the dietitian's certificates(p<0.001). Both Groups of professors(77.8%) and the graduates(65.1%) had significantly higher answer than groups of dietitians(56.1%) and the students(56.5%) to the question that 3 year-period of education is proper(p<0.001). Therefore the educational system should be reorganized into the three year-period of education as soon as possible for the effectiveness of the education of the dietitians, for the higher acquisition of dietitian's certificate, for the increase of field education, for the development of the student's creativeness and for the various courses after the graduation.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.4
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• pp.465-474
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• 2014

PURPOSE: This study aims to provide basic materials to re-establish terms and to build the institutional framework for the home and visiting physical therapy. METHODS: For such purpose of the study conducted the research that targeted the physical therapists, who were working at the rehabilitation hospital located in Gyeonggi-do as for the survey questionnaires as to the need and awareness of development of the adequate insurance fee of home physical therapy and visiting physical therapy. RESULTS: The survey result shows the awareness is low on the term separation in referring the home physical therapy and the visiting physical therapy. On the question regarding the performance obligation in the current system of the home and the visiting physical therapies, the answers for the recognition are shown to be 58% and 88.1% while no significant differences according to ages and working periods are found in all questions (p>.05). In the meanwhile, on the question regarding necessities of the home and the visiting physical therapies, answers agreeing the necessity is shown as 96.3%. And, on the question regarding the expected effect, the score shows to be very high with 40.5 points out of 50 points and significant differences according to the age and the working period (p<.05). CONCLUSION: It directly reflects the result, as the age and the working period are longer, the necessity shows to be higher.