• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.69-72
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• 2003

In this paper new control strategy of series resonant converter system for control power supply is suggested. Frequency controlled series resonant converter system is robust to load variations because it is POSR(parallel output series resonant) type. And it provides stable output voltage by changing switching frequency to input voltage variations. Firstly, operation analysis about suggested series resonant converter system was carried. Then simulations using ACSL(Advanced Continuous Simulation Language) and experiments to actual system were carried to prove characteristics of suggested system.

• Journal of Korea Society of Digital Industry and Information Management
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• v.4 no.4
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• pp.51-62
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• 2008

In this paper, the proposal system can achieve the more safety of RFID System with the 2-step authentication procedures for the enhancement about the security of general RFID systems. After authentication RFID Tag, additionally, the proposal system extract the characteristic information in the user image for acquisition of the additional authentication information of the user with the camera. In this paper, the system which was proposed more enforce the security of the automatic entrance and exit authentication system with the cognitive characters of RFID Tag and the extracted characteristic information of the user image through the camera. The RFID system which use the active tag and reader with 2.4GHz bandwidth can recognize the tag of RFID in the various output manner. Additionally, when the RFID system have errors, the characteristic information of the user image is designed to replace the RFID system as it compare with the similarity of the color, outline and input image information which was recorded to the database previously. In the result of experiment, the system can acquire more exact results as compared with the single authentication system when it using RFID Tag and the information of color characteristics.

• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.1212-1220
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• 2013

In general, for a large power system like DC distribution system for buildings, several power converters are modularized for parallel operation. However, in parallel operation, inconsistency of parameters in each module causes circulating current in the whole system. Circulating current is directly related to loss, and, therefore, it is most important for the safety of the power system to supply the suitable current to each module. This paper proposes a control method to reduce circulating current caused during parallel operation. Accordingly, the validity of parallel operation system including response characteristics and normal state was verified by simulation and experiment result.

• Agribusiness and Information Management
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• v.3 no.1
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• pp.38-66
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• 2011

The dissemination process of agricultural research and development (R&D) results has somewhat different characteristics from that of typical R&D results. However, these characteristics are not adequately considered on the basis of an examination of the current performance system, the resulting management plans, and strategies for the application and dissemination of the results of agricultural R&D in Korea. The performance evaluation indicator exposed the problem of the inadequate consideration of the characteristics of each of these areas, particularly the lack of unified R&D-related institutions and the inadequacy of the system to monitor outcomes. To address these shortcomings in the agricultural R&D programs in Korea, the policies pertaining to agricultural R&D performance, results management, and dissemination in the U.S. and Japan were examined. Based on these investigations, we proposed strategies to improve the agricultural R&D policies in Korea.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.12
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• pp.3416-3435
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• 2023

Task offloading in vehicular networks is hot topic in the development of autonomous driving. In these scenarios, due to the role of vehicles and pedestrians, task characteristics are changing constantly. The classical deep learning algorithm always uses a pre-trained neural network to optimize task offloading, which leads to system performance degradation. Therefore, this paper proposes a neural network fine-tuning task offloading algorithm, combining with location prediction for pedestrians and vehicles by the Payne model of fluid dynamics and the car-following model, respectively. After the locations are predicted, characteristics of tasks can be obtained and the neural network will be fine-tuned. Finally, the proposed algorithm continuously predicts task characteristics and fine-tunes a neural network to maintain high system performance and meet low delay requirements. From the simulation results, compared with other algorithms, the proposed algorithm still guarantees a lower task offloading delay, especially when congestion occurs.

• Korean Journal of Oriental Medicine
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• v.14 no.3
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• pp.113-119
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• 2008

In pulse diagnosis, the indentation pressure is one of the most important factors as well as the change of pulse shape and the distribution of pressure via time. But, on the oriental medical doctor's indentation pressure control, the understandings of the neurophysiological meanings and mechanisms have been lacked. So, in this paper, we considered on these issues and then proposed a proper system which can imitate the OMD's indentation pressure control mechanisms. As a result, both tactile information and kinesthetic information were found to be essential to the indentation pressure control so that a system, which can measure both the physical indent pressure and the displacement of an indentation arm, has been proposed. With this proposed system, while the indentation was being controlled through the moving step number of the step motor, the physical indentation pres sure and displacement of the indentation arm were measured. From these measured data, the relationships between the moving step number and both physical indentation pressure and displacement were revealed to have linear characteristics in early phase and to have nonlinear characteristics in latter phase. Additionally, three types of graph were generated whose X axis means the moving step number, the physical indentation pressure and the displacement respectively and Y axis means the pulse pressure. By comparing these graphs, we come to conclude that different concepts on indentation pressure control cause different diagnostic results on floating/sinking degrees for the same subject. Consequently, an indentation system for the pulse diagnosis should be able to provide both the tactile information and kinesthetic information, that is, the physical indentation pressure and the displacement of the indentation arm. In future, the proposed system should be optimized to the pulse diagnosis environment and how to combine the both information for more reliable diagnosis should be studied.

• Korea Journal of Hospital Management
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• v.7 no.2
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• pp.80-98
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• 2002

The purpose of this study was to investigate user satisfaction at Defense Medical Information System as it has been utilized as a part of National Defense Information Strategies since Aug. 2000. The subjects of this study were nurse officers and army surgeons of a hospital with 1,000 beds. The results of this study are as follows; First, according to the characteristics of the subjects, there was statistically significant difference in system satisfaction, job satisfaction and information satisfaction at Military Hospital Information System. Second, according to the intention of participation, there was a statistically significant difference in user satisfaction at Military Hospital Information System. Third, according to a level of dexterity at Military Hospital Information System, there was statistically significant difference only in job satisfaction. Fourth, factors to influence system satisfaction were one's duty, using period of Military Hospital Information System, and a level of dexterity at Military Hospital Information System. Factors to influence job satisfaction were a level of dexterity at Military Hospital Information System, one's duty and intention of participation. Factors to influence information satisfaction were one's duty, a level of dexterity at Military Hospital Information System, and intention of participation. As the first study on user satisfaction at Military Hospital Information System, this study suggests the followings. First, a plan to inspire users with intention of participating in information system should be prepared. Second, it is necessary to provide policy activities for job standardization of Military Hospital Information System and legal system improvement.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4C
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• pp.262-268
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• 2005

The unit of the digital content delivery is the web object. For the improvement of the content delivery based on the web, it id required analysis of reference characteristics of the web object. In this study, we analyze reference characteristics of the web object and evaluate the performance. Using these analysis results, we propose the digital content delivery system which is improved delivery efficiency. The goal of the proposed system are the improvement of the processing time through enhancement of the caching efficiency with reflect reference characteristics of the web object. And the experiment result, we verify the performance enhancement.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.201-207
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• 2007

In some manufacturing industries, there are many situation in which the simultaneous monitoring or control of two or more related quality characteristics is necessary. However, monitoring these two or more related quality characteristics independently can be very misleading. When several characteristics of manufactured component are to be monitored simultaneously, multivariate $x^2$ or $T^2$ control chart can be used. In this paper, establishing a early warning system(EWS) using multivariate control charts to analyze early out-of-control signals in melting process with many quality characteristics was presented. This module which we developed to control several characteristics improved efficiency and effectiveness of process control in the melting process.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.1
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• pp.39-45
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• 2011

The processes for manufacturing a product differ depending on the characteristics of the product, and the information used or generated by the processes also varies. To implement a flexible and configurable Manufacturing Execution System (MES), a Data Acquisition System (DAS) that takes into consideration the characteristics of the manufacturing system is required. In this study, we design an information acquisition system that can process the information on equipments of a shop floor in real-time and that is adaptive to the changes in the shop floor. The system has a data parser module for flexible processing of the equipment status, a data mapper module to link the equipment status with a manufacturing process, and an SOA-based data integration module to transmit the processed information to other information systems such as MES and ERP. From the results of pilot study, its maintenance is easy even if new equipment or new manufacturing processes are adopted or if the equipments are rearranged.