• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.4
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• pp.344-350
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• 2014

Multi Function Display(MFD) of Korean Utility Helicopter(KUH) is the component of mission management/display control system and displays image information(navigation, flight, survivability, digital map, maintenance) acquired from Mission Computer(MC) while the aircraft is operated. It is an essential equipment for pilots to perform flight mission and it has functions of display scene control, data display, built in test(BIT) and brightness control. In this paper, it is analyzed the cause of abnormal display(flickering) on MFD and summarized the design changes to solve the defect. It is also described system safety analysis and suggested verification results of flight/ground test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.76-82
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• 2019

This study has done to search for a solution to remove risk limitedly caused by separating weapon system acquisition from operation and maintenance at the view point of Logistic Commander who's responsible for stable operation and maintenance after acquiring weapon system. At the System development stage, unverified overhaul development plan may cause additional manpower and costs after the development, and furthermore it is likely to have risk to lower reliability of the military. Thus, research and development agency should write overhaul development plan at the System development stage, and it should be verified through evaluation and verification test. Secondly, during research and development, institutional supplementation is needed to calculate human and material resources writing overhaul development plan. Thirdly, it should be able to analyze proper operation & maintenance plan and cost for overhaul plan at the pre-investigation stage. Fourthly, the base which can develop overhaul concept and overhaul factors should be included in the need and need determination document. Lastly, for the weapon system which has small amount of high power figure, project management should be performed to be able to specify at the each acquisition level of weapon system to realize Article 28, clause 3 and 4 of Defense business law.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.5
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• pp.121-132
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• 2009

The agency which is responsible for work related to the restoration of vegetation on the quarry in Hong Kong is the Geotechnical Engineering Office of Civil Engineering and Development Department (CEDD). CEDD's environmental management system was certified as ISO 14001 : 2004 in 2006 and diverse instructions and technical documents about the restoration of the quarry were published and used for the performance of work and the implementation of the project. The restoration of the quarry is being carried out to respond to short-term and long-term goals. The general instructions for the restoration of vegetation says that a plant, when selected, should be self-sustainable with minimum maintenance required, have a high growth and survival rate, be tall enough to cover the rock slope faces, and preferably produce colourful flowers. These instructions prescribe the vegetation introduction technology, planting seasons, structural material of the vegetation works, maintenance and management, tree nursery operation, means of water supply, etc. This report introduced the outline of work on restoring vegetation carried out at Anderson Road, Shek O, Lam Tei, Turret Hill, Lamma, all large-sized quarries. In addition, it additzed Anderson Road's master plan. It is hoped that the Hong Kong examples so introduced are referred to in terms of institutional and technical considerations related to the nation's project for restoring quarries.

• International Journal of Highway Engineering
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• v.19 no.4
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• pp.9-18
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• 2017

PURPOSES : This study evaluates the reasonableness of the recommended amount of deicing chemicals based on historical data for snow removal. The result can be used to aid decision-making for the reservation of cost-effective de-icing chemicals. METHODS : First, the recommended amount of de-icing chemical to use and historical usage data were evaluated to identify specific usage characteristics for each region. Road maintenance length and snow-removal working days were analyzed over the past five winter seasons. Next, differences in the recommended amount of chemical to use and actual use were compared using the Kolmogorov-Smirnov test. Last, the two types of data were analyzed using a chi-square test to verify if the two distributions of variation pattern are statistically significant. We found that there are significant differences between the data from each region during the past five winter seasons. RESULTS : The results showed that the equation for calculating the amount of de-icing chemical to use appears to be revised. CONCLUSIONS : The results imply that the equation for calculating the amount of de-icing chemical to apply as a national standard is very important when the public agency makes decisions related to snow-removal.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.219-224
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• 2020

This study is based on the principle of solar power system and fire breakout. The result of the survey indicates that a solar power system is vulnerable to fire due to lack of maintenance after the installation. Currently the national fire safety agency does not have standards and legal provisions for the installation and maintenance of solar power facilities. Therefore, it increases the risk of fire breakouts as well as possibility of electric shock for the firefighters during fire fighting. This results possible damages to the human and equipments. In this study is proposing an automatic fire extinguishing system to reduce the power generation of solar panels during fire breakouts. Also, propose an over load current alarm system and fire prevention measures for fire fighters. The results of this study will be used as basic data for further fire testing of solar power systems.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.3
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• pp.37-49
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• 2007

This study investigated how external environmentally-friendly factors adopted to improve the quality of outdoor spaces have been designed and used in the construction of apartment complexes. The goal of this study is to determine what areas should be improved through environmentally-friendly ways to create natural outdoor spaces in apartment complexes and enhance their availability and usefulness. For this study, 21 environmentally-friendly factors were chosen and a checklist by specific item was prepared. This study examine how these items were applied to basic planning, detail design, and construction in 4 target areas. As a result, it was found that the development of environmentally-friendly residential areas was an ultimate goal of the project during basic planning and design. All target areas focused on developing an inner greens network, eco-pond, brook, and pedestrian track as well as the growth of a variety of plants. Some differences have been observed, however, in terms of method. Furthermore, due to economic and technological problems and poor construction site conditions, green walls/green roofs/pedestrian tracks/use of rainwater have not been properly promoted. These kinds of problems must be improved through the development of environmentally-friendly construction methods and materials, the expansion of natural grounds areas, economic support, a satisfactory repair and maintenance system.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.1-12
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• 2015

PURPOSES : This paper presents a description of the current issues facing road managers regarding the surface-type conversion of low-volume roads for cost savings. METHODS: The paper reviews previous works conducted toward this end, acknowledges gaps in the current research, and lays out what information is needed for further studies. RESULTS : If the cost to maintain an unsurfaced road is less than the cost of maintaining a surfaced road, then there is potential for cost savings for the management agency. However, the problem is bigger than simply maintaining the roads that already exist. If unsurfaced roads prove to be more economical than surfaced roads, then the cost to convert from a surfaced to an unsurfaced roadway, and vice versa, when necessary, must also be examined. CONCLUSIONS : No other studies have addressed the un-surfacing of a road for cost savings, and it is therefore unknown whether substantial savings can be realistically obtained by converting from a surfaced to an unsurfaced road. To determine whether a conversion policy would be a viable option, additional data and research are needed.

• International Journal of Advanced Culture Technology
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• v.9 no.2
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• pp.106-117
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• 2021

The aim is to find cyber measures in consideration of physical CPTED in order to prepare countermeasures for cybercrime prevention. For this, the six applied principles of CPTED were used as the standard. A new control item was created in connection with the control items of ISO27001. A survey was conducted on former and current investigators and security experts. As a result of the reliability analysis, the Kronbar alpha coefficient value was 0.947, indicating the reliability of the statistical value. As a result of factor analysis, it was reduced to six factors. The following are six factors and countermeasures. Nature monitoring blocks opportunities and strengthens business continuity. Access control is based on management system compliance, personnel security. Reinforcement of territoriality is reinforcement of each wife and ethics. Establishment of security policy to enhance readability, security system maintenance. Increasing usability is seeking ways to utilize, periodic incentives. For maintenance, security education is strength and security-related collective cooperation is conducted. The differentiation of this study was to find countermeasures against cybercrime in the psychological part of the past. However, they approached to find in cyber measures. The limitation of the study is to bring the concept of physical CPTED to the cyber concept.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.345-350
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• 2021

The maintenance of sensor networks, installed in a wide area has been an issue for a long time. In order to solve this problem, studies to supply energy to a sensor network using a robot has been carried out by several researchers. In this study, for a sensor network consisting of power nodes supplied with energy by multiple robots and sensor nodes around them, we propose a method of allocating a work area using a modified k-means algorithm so that the robots move the minimum distance. Through the simulation study using the energy transfer rate of the robot as a variable, it is shown that nodes of each allocated area can maintain survival, and the validity of the proposed modified k-means algorithm is verified.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.801-806
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• 2021

Rail corrugation is continuously increasing due to the lack of maintenance regulations for the amount of rail irregularities. Rail corrugation is causing various problems, such as a decrease in ride comfort and an increase in the amount of track maintenance. In this paper, the effect of rail corrugation on the track force was analyzed by measuring the rail irregularities before and after rail grinding and the track measurements (dynamic wheel load, displacement, and acceleration) for the section where the rail corrugation occurred. In addition, it was experimentally proven that the rail grinding performed to reduce the corrugation of the rail was very effective in reducing the additional forces on the track.