• Journal of the Korean Solar Energy Society
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• v.36 no.5
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• pp.19-30
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• 2016

In this study, realize voltage regulation $220Vac{\pm}10%$ or less, frequency fluctuation $60Hz{\pm}1%$ or less over the independent operation and grid-connected operation technologies for power stabilization relates to the ESS designed and manufactured in conjunction with solar installations and solar to compensate the output reduction due to the polarization of the solar module through the polarization prevention technology for preventing the optical module efficiency is lowered, in conjunction with the BMS inverter efficiency was more than 92%, more than 90% of the charging efficiency to the target. This study was designed in conjunction with the ESS solar power plants, grid-connected operation and independent operation, Peak-Cut, it can stabilize the grid via the Peak-Shifting operation

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.229-238
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• 2013

This study was conducted to analyze on the operational cost of logging operations in the whole-tree logging operation system by tower-yarder and swing-yarder, and in the cut-to-length logging operation system by excavator with grapple in order to spread efficient logging operation technique and to establish the logging operation system. In the results of the analysis of operation cost, in case of the whole-tree logging operation system, the operation cost was 2,099 won/$m^3$ in felling by chain saw, 28,286 won/$m^3$ in yarding by tower-yarder, 18,265 won/$m^3$ in yarding by swing-yarder, 18,939 won/$m^3$ in bucking by excavator with grapple and chain saw, 20,484 won/$m^3$ in forwarding and accumulation by wheel type mini-forwarder, 12,701 won/$m^3$ in forwarding and accumulation by excavator with grapple and small forwarding vehicle. In case of the cut-to-length logging operation system, the operation cost was 10,160 won/$m^3$ in felling and bucking by chain saw, 7,567 won/$m^3$ in cut-to-length extraction by excavator with grapple, 6,982 won/$m^3$ in branches and leaves extraction by excavator with grapple, 3,040 won/$m^3$ in the operation road construction by excavator with grapple, 20,484 won/$m^3$ in forwarding and accumulation by wheel type mini-forwarder, 12,701 won/$m^3$ in forwarding and accumulation by excavator with grapple and small forwarding vehicle.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1064-1069
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• 2014

The railway signalling system plays an essential role in the headway and routing control for a safe and efficient train operation. The reliable and safe operation of the system is very important because the failure of the railway signalling system can lead to the collision, derailment, or unexpected stop of a train. So far, the conventional wayside signal mode (ATS: Automatic Train Stop) has been generally used as the railway signalling system. However, this system is highly linked to a risk of major accidents resulted from human mistakes such as missing a signal or careless control of train speed. Accordingly, the onboard signal mode (ATC: Automatic Train Control) as an alternative of ATS has been recently introduced and applied to transmit effectively the information on speed control of a train by using computers and communication equipment. In the process of replacing the obsolete signal system, it is necessary to switch over the system while providing passengers with normal services. Therefore, the integration of a railway signaling system compatible for both ATS and ATC and its interface is discussed in this study. In particular, the implementation scenario required for operation planning of the integrated system was designed, and the results as well as effects of its applicability test were also presented.

• Journal of the Society of Disaster Information
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• v.10 no.2
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• pp.282-286
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• 2014

This study is to present an improvement of physical security system operation by survey on the install and operation of physical security system of 90 facilities. The level of CCTV operation is higher than Access Control system and Intrusion Detection System. But the level of maintenance and management of physical security system is low. The rate of install of X-ray Inspection device show the concern on material detection, although the rate is low. The level of install and operation for the Integration of physical security system is low, so integration of security personnel and security system is necessary for the effective operation. For reinforcement of access control management, security gate and preparing of some obstacles are required with RFID.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.9 no.2
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• pp.77-89
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• 2001

Recently, the development of an airship that flies through the stratosphere was undertaken in Korea by Korea Aerospace Research Institute like other countries. With the consideration of new operation concept, it is on the rise that the current certification requirements and operation system is not sufficient to secure safety and reliability. This study was performed to establish the certification requirements and operation system. The amendment of airworthiness standards was reviewed by each articles, and the new procedures, as a level of national regulations, for operation was proposed. The results gained through this study can be utilized effectively in the development and operation of subjected airship.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.108-108
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• 2003

본 논문에서는 과학위성 2호의 주 탑재체인 LIST의 Operation에 대한 개념을 소개하고자 한다. LIST는 태양 진공자외선(Lyman-$\alpha$)의 full disk 영상을 획득하고 분석함으로서 채층과 전이영역의 구조와 진화, ‘Quiet Sun’의 진공자외선 복사 변화 모델, 그리고 태양 진공자외선의 복사로 인한 지구 고층 대기의 변화를 밝혀내는 것이 목표이다. 이러한 목표를 성공적으로 수행하기 위해서는 LIST Operation 개념의 정립과 철저한 규정이 필요하다. 따라서 본 연구진은 Operation을 크게 두 부분으로 세분하였다. 즉, LIST의 각 구성 요소들이 유기적으로 작용, 목적하는 데이터의 성공적인 획득을 위한 ‘Technical Operation’과 획득된 데이터를 활용하여 효과적으로 분석하고 목적한 과학적 성과를 달성하기 위한 ‘Scientific Operation’으로 구분하여 규정하였다. 또한 효율적인 Data System의 관리를 위해 데이터의 흐름을 ‘LIST Observing System’, ‘LIST Data Acquisition System’, ‘LIST Data Reduction and Analysis’, 그리고 ‘LIST Data Analysis and Publication’의 네 가지 단계로 나누어 Data의 활용 중에 나타날 수 있는 위험들을 최소화 하고자 하였다.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.16 no.4
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• pp.1-8
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• 2020

For a central cooling system of a medical facility composed of absorption chiller and screw chiller, the study was conducted on how to minimize the energy cost. In consideration of the energy cost, the optimal operation method in which the operation method of the heat source is changed according to the size of the cooling load was derived through simulation analysis. When applying the optimal operation method, the indoor environment, energy consumption, and energy cost were analyzed and compared with the reference operation method.

• Korean Journal of Computational Design and Engineering
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• v.18 no.2
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• pp.120-128
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• 2013

Recently, the importance of the HVAC system (Heating, Ventilating and Air Conditioning System) is growing because comfortable working environment has emerged as important element for enhancing work efficiency. HVAC system is a general term of a system that collectively creates desired temperature and state through heating and air conditioning. HVAC system consists of many objects, so it requires a lot of constraints for its effective operation. Thus, specific strategy is needed for an optimal operation of HVAC System for plant. In this paper, manufacturing plants which have HVAC systems has been modeled and the objective function and constraints for an effective operation have been defined. And new strategy for an effective operation of HVAC system with energy simulations has been proposed.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.4
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• pp.473-477
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• 2013

The railway developed countries in Europe, Japan such as ERTMS Regional, FFB, COMBAT, it is the stage of development or testing the train control system for the signal system of branch interval of low density. Similar to the signal system used by the mainline and branch sections of low density domestic portions not suitable in terms of maintenance operational efficiency in accordance with the installation and operation in many cases. Therefore these low-density branch railway lines required that oriented train control system of wireless communication to improve the operation efficiency and line side equipment controlled on board the train. In this paper, We was published a route on setting is the operation of the new on-board oriented train control system for controlling a line converter of the train so that it is possible to improve the operational efficiency of the branch of the low density.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.2
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• pp.317-324
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• 2007

Most conventional hybrid systems using renewable energy sources have been applied for stand-alone operation, but Utility-interface may be an useful and viable option for hybrid systems. Grid-connected operation may have benefits such as reduced losses in power system distribution, utility support in demand side management, and peak load shaving. This paper addresses power control and dynamic performance of a grid-connected PV/wind/BESS hybrid system. At all times the PV way and the wind turbine are individually controlled to generate the maximum energy from given weather conditions. The battery energy storage system (BESS) charges or discharges the battery depending on energy gap between grid invertger generation and production from the PV and wind system. The BESS should be also controlled without too frequently repeated shifts in operation mode, charging or discharging. The grid inverter regulates the generated power injection into the grid. Different control schemes of the grid inverter are presented for different operation modes, which include normal operation, power dispatching, and power smoothing. Simulation results demonstrate that the effectiveness of the proposed power control schemes for the grid-interactive hybrid system.