• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.249-250
• /
• 2015

Technological advance of power elcetronic devices using semiconductor switches in last several decades, invoke the increase of switching devices' penetration in the system like STATCOM or HVDC and also, increase the difficulty to adjust switching characteristics in the virtual simulating configuration, which are not capable of reflect the detailed phenomena. To investigate harmful effect of switching devices into the grid, detailed modeling of power electronic devices are necessary, and the first step for entire grid modelling is simulate power system in time domain model. In this paper, simple two bus system with synchronous generator and infinite bus on the other side has been compromised in two simulation environment, using PSS/E and Matlab/Simulink. Comparing the result of two simulation result will give answers to the fundamental difference between two type of simulation environment.

• Archives of design research
• /
• v.19 no.4 s.66
• /
• pp.61-70
• /
• 2006

The functions and roles in the various fields of modern society are changing into the unified and multiplex structure, which is simultaneous and virtual communication environments beyond physical space and time, by the digital IT technology. The urban traffic system is also being intellectualized in order to solve urban traffic problems and convenient services by using digital IT technology. The bus, which is the one of the most common public transportation, are suffering in the decrease of bus service quality and the bus passengers rate because of the development of other public transportation systems such as the subway and electric railway and by rapidly increasing private cars. By recognizing these problems, many domestic and overseas cities are promoting to introduce the Bus Information System (BIS) to improve service quality of buses through the intelligent traffic system. According to the construction of this new information system called the Bus Information System (BIS), the new bus stop configuration system and design plans are being required to solve the existing bus stop information system. Therefore, this research was conducted to suggest an effective BIS configuration system plan and synthetic design goals based on the investigation the problems of the information system and the BIS configuration system for Busan city. Also, this research are conducted the below actions as follows: First, the literature survey was conducted, such as theoretical documents on the bus stop and the Bus Information System(BIS), Also, the design trend of the BIS was examined through domestic and overseas BIS cases studies. Scondly, the problems related to the information system in Busan city bus stops were investigated to investigate the present state and problems of the Bus Information System (BIS). Finally, as a result of this research, the effective BIS configuration system plan and design approach methods of bus stops were proposed for by Busan city based on the above investigation results.

• Journal of the Korean Society of Industry Convergence
• /
• v.18 no.1
• /
• pp.61-66
• /
• 2015

Force feedback control is investigated for improving the quality of the haptic feedback in virtual reality applications. We proposed method for control of the haptic device using universal serial bus. and evaluated the characteristics with experimental set.

• Proceedings of the KIEE Conference
• /
• 2002.07d
• /
• pp.2665-2667
• /
• 2002

Force feedback control is investigated for improving the quality of the haptic feedback in virtual reality applications. We proposed method for control of the haptic device using universal serial bus(USB), and evaluated the characteristics with experimental set.

• Korea Journal of Hospital Management
• /
• v.1 no.1
• /
• pp.170-187
• /
• 1996

This paper proposes a change process model for organization development in health care organizations and provide an OD case exemplar of nursing service unit at Virtual Hospital. This case exemplar was written in a narrative form rather than in an argumentative form as an embodiment of organization development process as is viewed from the cultural/interpretive perspective rather than from the technical/rational one. This case exemplar illustrates the change process which consists of four interrelated components: change intervention, organizational target variables, individual organizational member, and organizational outcomes. It also demonstrates the applicability of the narrative rationality which involves narrative probability and narrative fidelity to the story where the learning organization, shared governance, and empowerment are fully emplotted and enlivened. The implications for organization development in health care organizations are discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.664-665
• /
• 2013

This paper present a method of constructing the multimedia processor architecture. The proposed multimedia processor architecture be able to handle each text, sound, and video in one chip. Also it have interactive function that is a characteristics of multimedia. Specially, the proposed multimedia processor be able to addressing nodes in memory map without software, and it is completely reconfigurable depend on data. Also it as able to process time and space common that have synchronous/asynchronous and it is able to protect continuous and dynamic media bus collision, and local and overall common memory structure. The proposed multimedia processor architecture apply to virtual reality and mixed reality.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.1
• /
• pp.93-103
• /
• 2019

In metropolitan cities have been reorganizing the routes of the city buses periodically due to changes in the spatial structure and traffic pattern and the lack of supply due to new developments. However, there is a lack of system to comprehensively evaluate the routes. Even if the evaluation index is not clearly defined, it may not be reasonable. Therefore, it is difficult to set the improvement direction when the bus route is reorganized. In this study, the existing evaluation indexes were reviewed and further investigation was conducted on the problematic indexes. In particular, the degree of curvature has been used as a very important index in the evaluation of the route system, but the existing curvature based curvature has a limitation in considering the traffic characteristics of individual users. For this purpose, a virtual city bus network was set up and the degree of curvature was calculated and compared based on the point - based curvature and stopping point based on individual user O/D. In this study, it is considered that more efficient and practical analysis and evaluation are possible in the evaluation of the city bus route system through the curvature considering the individual user O/D based on the stopping point. It is expected that it will be used at the time of reorganization of city bus route performed by individual local governments in the future.

• Journal of Advanced Information Technology and Convergence
• /
• v.10 no.2
• /
• pp.91-101
• /
• 2020

Recently, the demand for high penetration of variable renewable energy (VRE) penetration in a power system is increased. In consequence, distribution systems including microgrids confront the increased installation of VRE-based distributed generation. Despite of the high demand of VRE-based distributed generation in a distribution system, the installation of photovoltaic (PV) system in a distribution system has been restricted by various problems. In other words, the hosting capacity for high VRE penetration in a distribution system is limited. This paper analyzes the improvements of hosting capacity VRE penetration of stand-alone microgrid (SAMG) with energy storage system (ESS) by considering virtual-slack (VS) control based on power sensitivity. With the pre-defined power sensitivity, the ESS operates as virtual slack in the SAMG by controlling its bus voltage and phase angle indirectly. Therefore, the ESS enables the increase of VRE penetration in the SAMG. The proposed VS control is realized by analyzing the ESS as a virtual slack in power flow analysis based on power sensitivity. Then its validity is demonstrated with the case study on the SAMG in South Korea with practical data.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.2
• /
• pp.257-265
• /
• 2011

As the competitive market system has been introduced to the electrical power trade, the priority concern would be that the price of electrical power should be reasonable. It is because, when this rule is solid, we can avoid the distortion of competition and assure the greater efficiency in management. LMP(Locational Marginal Price) means marginal price at each bus. This components consist of energy, loss and congestion cost. At this point, the LMP result that is calculated by traditional model is changeable by the location of the slack and can not be used in bilateral Transaction. This paper proposed algorithm is proved its rationality and credibility by comparing the result of the simulation of virtual 6_bus system that is calculated by traditional method, and showed that the LMP components are changed according to the Transaction Strategy. Furthermore, It shows the effect of additional congestion cost on the transmission line that has bottle neck frequently by simulation.

• Journal of Auto-vehicle Safety Association
• /
• v.15 no.4
• /
• pp.16-22
• /
• 2023

This paper presents a proactive longitudinal motion planning algorithm for improving the safety of an automated bus. Since the field of view (FOV) of the autonomous vehicle was limited depending on onboard sensors' performance and surrounding environments, it was necessary to implement vehicle-to-vehicle (V2V) communication for overcoming the limitation. After a virtual V2V-equipped target was constructed considering information obtained from V2V communication, the reference motion of the ego vehicle was determined by considering the state of both the V2V-equipped target and the sensor-detected target. Model predictive control (MPC) was implemented to calculate the optimal motion considering the reference motion and the chance constraint, which was deduced from manual driving data. The improvement in driving safety was confirmed through vehicle tests along actual urban roads.