• Journal of Korean Society of Water and Wastewater
• /
• v.21 no.1
• /
• pp.47-55
• /
• 2007

The waste water treatment facility at rural and mountainous region in catchment areas of dams should be small scale. The wastewater treatment facility of small scale has some specification as follows;1)simple process, 2)low maintenance cost, and 3)high removal efficiency. So, we developed the bioreactor which can be satisfied with the specification of small scale waste water treatment facility. The bioreactor consisted of the anoxic and oxic zone. The two zones were effectively separated by cone type baffle. By the effective separation through CTB, the nitrification and denitrification reaction occurred effectively. Therefore, the removal efficiency of total nitorgen (TN) increased compared to other types of baffle. And, we put into the bio activated media in oxic zone to increase the concentration and activity of microbiology. The media contained the components which were made of many kinds of the minerals to increase the activity of microbiology. Additionally, we observed that the phosphate removal efficiency increased by bio activated media. This is resulted from the coagulation-sedimentation reaction by mineral in components. The average removal efficiencies of TN and TP during Run 2 were 69 and 89% which were 4 and 25% higher than those during Run 1 without the MA, respectively. For BOD, COD, SS and TKN, the average removal efficiencies at Run 2 were slightly higher than those at Run 1. Therefore, we could maintain the high concentration and high activity of microbiology through bioreactor developed in this study. And the removal efficiency of TN and TP increased.

• The Journal of Sustainable Design and Educational Environment Research
• /
• v.17 no.2
• /
• pp.22-37
• /
• 2018

This study suggests desirable disaster safety education curriculum through analyzing the operational status of the school disaster safety management training course and demand survey of school staff. First, the problem of the disaster safety training course of the school is not connected with the lack of law and system and the school disaster safety job. Second, improvement of law and system and variety of training should be made to acquire professional knowledge. Third, it is necessary to divide curriculum into the following four categories, according to educational needs of public officials ; Educational administration officers course focused on facility safety, maintenance and disaster countermeasure. Educational officials in technical post course addressing approval and permission of school facility projects, seismic reinforcement of school building, etc. Educational supervisors course covering roles and responsibilities of the school safety supervisors in the event of disaster. Teaching staffs course focused on safety instructions for students. Fourth, it is found that lectures and experiential learning methods are the most desirable methods of teaching and learning, and the major ranks are earthquake disaster, fire, gas, typhoon, school road, and electrical safety.

• Journal of the Korea Convergence Society
• /
• v.11 no.9
• /
• pp.243-260
• /
• 2020

The purpose of this study is to analyze measures to promote a private finance initiative aimed at public facility regeneration in the midst of sharp increase in local financial burden due to the low birthrate and rapidly aging population. In particular, the study looked at the case of promoting a private finance initiative through a local platform aimed at public facility regeneration in Narashino, Japan. The study is based on the relevant systems and policies, and government documents and statistical data on the Narashino case. The results show that the local platform helps the local government and participants share business expertise and experiences, leading to improvements in their expertise and business capability. The local platform allows them to identify and discuss potential business ideas in advance, which in turn encourages private investment business.

• Journal of the Society of Disaster Information
• /
• v.17 no.1
• /
• pp.39-52
• /
• 2021

Purpose: Recently, due to increasing usage of high-tech equipment for facility inspection, the need of verifying high-tech equipment is being emphasized. Therefore, the purpose of this paper is to develop performance evaluation methodology of tunnel scanners that inspect tunnel facilities. Method: This paper describes literature reviews regarding the performance evaluation methodology of high-tech based equipment for facility inspection. Based on these investigations and expert advisory meetings, this paper suggests a performance evaluation methodology of tunnel scanner. Result: First evaluation indicator states minimum performance standards of tunnel scanners. Second evaluation indicator is related to tunnel scanner quality. Conclusion: The performance evaluation methodology can provide reliable equipment performance catalogues, helping users to make a proper selection of equipment. Also, developers of equipment can get authorized verification of performances, preventing poor maintenance of facilities.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.42 no.3
• /
• pp.399-407
• /
• 2022

Energy absorption facilities installed on roads should follow the performance standards of the real-car crash test of 'Installation and Maintenance Guidelines for Roadside Safety Facilities'. However, due to different installation conditions, such as differing structure widths on roads, some energy absorption facilities do not provide adequate performance. In order to apply varied environments on roads, an energy absorption structure was designed in this study with 150 mm height and four layers of W-shape guardrail at 200 mm intervals, and the performance was verified using LS-DYNA computer simulation. Through a real-car crash test, the performance of the facility designed by LS-DYNA was tested and was found to meet the performance of the CC2 category for crash cushions. The conclusion of the comparison demonstrates that the simulation and the real-car crash tests are both significant.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.31 no.2
• /
• pp.39-44
• /
• 2023

This study was conducted to analyze problems related to non-water-soluble sanitary products during the treatment of water regeneration centers in E.T.F. and S.T.F. at a time when the demand and supply of non-water-soluble sanitary products are increasing. As a result, the improvement plan of the W.R.C. should focus on pretreatment facilities. When replacing facilities in the future, various dust removers suitable for the facility's reality will be installed in the pretreatment of S.T.F., and it is proposed to link a bar-racks screen with a comprehensive treatment device or install a comprehensive treatment device for impurities alone in the pretreatment of E.T.F.. In addition, a microscreen screen must be installed on the front end of the excretory treatment unit. to separate non-water-soluble materials, and it is necessary to secure a maintenance space for the excretory treatment unit.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.5D
• /
• pp.627-634
• /
• 2009

The BTL (Build-Transfer-Lease) contract of construction project serves as a part for early establishment of industrial foundation for social overhead capital. However, project cost of BTL contract is focused on initial construction cost. Accordingly, operation cost is lowly evaluated because there is no standard criterion for estimating maintenance cost for the facility. The low operation cost can be a factor that reduces service quality of facility operation. This study suggests a resonable method for estimating cost and manpower in the operation phase by using the existing practical data for wastewater treatment plant by BTL contract. The results of the study can be used for evaluating rough operation cost and manpower of similar plant project by facility size.

• Journal of Wetlands Research
• /
• v.18 no.4
• /
• pp.448-455
• /
• 2016

Diffuse pollution management in Korea initiated by the Ministry of Environment (MOE) resulted to the construction of pilot facilities termed Best Management Practices (BMPs). Twelve BMPs installed for the diffuse pollution management in the Kyung-An Stream were monitored since 2006. Data on the mass loading, removal efficiency, maintenance activities, etc. were gathered and utilized to conduct the evaluation of long-term performance of BMPs. The financial data such as actual construction, design and maintenance cost were also collected to evaluate the lifecycle cost (LCC) of BMPs. In this study, most of the maintenance activity was focused in the aesthetic maintenance that resulted to the annual maintenance cost of the four BMP types was closely similar ranging from 8,483 $/yr for retention pond to 8,888 $/yr infiltration system. The highest LCC were observed in constructed wetland ($418,324) while vegetated system had the lowest LCC ($210,418). LCC of BMPs was not so high as compared with the conventional treatment facility and sewage treatment plant. On the other hand, the relationship of removal efficiency on unit cost for TSS and TN was significant. This study will be used to design the cost effective BMP for diffuse pollution management and become models for LCC analysis.

• The Journal of Engineering Geology
• /
• v.26 no.4
• /
• pp.473-484
• /
• 2016

This study aims to establish a monitoring method for managing the effective maintenance of tailings dams. The monitoring of a tailings dump area involves several parameters and their investigation through a selection of evaluation items. The extents of defects and progressive failures also need to be effectively estimated. Therefore, the monitoring items can be subdivided into categories relating to the retaining wall structure (concrete wall, reinforcing stone wall, mesh gabions) and general facilities (liner, covering soil, slope, tailings, rain protection facility, leachate, planting), and quantitative evaluations can then be conducted for each condition. In doing so, we developed a systematic monitoring method that assesses the dam maintenance condition with grades and scores. The field application of the monitoring method results showed it to provide a more detailed evaluation than existing monitoring methods: the method detected an additional 16 defects missed by conventional methods. The evaluation gave scores of 89.3, 22.2, and 27.8 to the Geumjang mine tailings dam, the Gupoong mine tailings dam, and the Hwachun mine tailings dam, respectively. The advanced method can provide quantitative evaluation and perform detailed monitoring of the dams. This quantitative evaluation can be used to decide on maintenance priorities, select the main management items, and establish schedules of maintenance.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.25 no.6
• /
• pp.569-582
• /
• 2023

In recent years, the service life of major SOC facilities in south korea has exceeded 30 years, and rapid aging is expected within the next 10 years. This has led to a growing recognition of the need for proactive maintenance of these facilities. Consequently, there have been numerous research efforts to introduce smart inspection technologies into maintenance. However, the current system relies primarily on manpower for safety inspections and diagnostics, and on-site surveys rely on visual inspections. Manpower inspections can be time-consuming, and subjective errors may occur during result analysis. In the case of tunnels, there are disadvantages, such as the loss of social overhead capital due to partial closures during inspections. Therefore, institutionalizing smart safety inspections is essential, considering specific measures like using advanced equipment and updating qualifications for experts. Furthermore, it is necessary to verify and validate safety inspection results using advanced equipment before instituting changes. This could be achieved through national-level official research programs and the operation of verification and validation institutions. If smart inspection technology is introduced into maintenance, routine inspections of SOC facilities, such as tunnels, will become feasible. As a result, maintenance technology capable of early detection and proactive response to safety incidents caused by changes in facility conditions is anticipated.