• Title/Summary/Keyword: Maintenance and Repair

Search Result 1,062, Processing Time 0.023 seconds

Distribution of Fish Species in Wetland Protected Areas in South Korea

  • Chu, Yeounsu;Yoon, Jungdo;Cho, Kwang-Jin;Kim, Mijeong;Lim, Jeongcheol;Lee, Changsu
    • Proceedings of the National Institute of Ecology of the Republic of Korea
    • /
    • v.2 no.1
    • /
    • pp.42-52
    • /
    • 2021
  • In order to secure basic data on biodiversity for wetland conservation and management used the data from Wetland Protected Area surveys conducted in South Korea (2015-2019) to analyze the distribution of fish from a total of 15 orders, 45 families, 134 species, and 12,972 individuals. The predominant species identified were Zacco platypus (Temminck and Schlegel) (19.47%) and Zacco koreanus (Kim, Oh and Hosoya) (8.16%). Of all emergent species, 52.9% (n=71 species) were freshwater species, 26.9% (n=36) were brackish species, 3.0% (n=4) were migratory species, 27% (n=36) were marine species, and 9.0% (n=12) were riffle benthic species. Overall, 5.2% (n=7 species) were endangered species, 3.0% (n=4) were exotic species, and 23.1% (n=31) were Korean endemic species. The eight identified Wetland Protected Areas (WPA) were classified based on their habitat characteristics and on the analysis of their emergent fish communities, as estuarine (n=2), coastal dune (n=1), marsh (n=2), stream (n=2), and stream-marsh (n=1) types. The environmental factors revealed to have the greatest influence on the species diversity of emergent fish were maintenance and repair, installation of reservoirs, and construction of artificial wetlands around them. The present study offers basic information on the diversity of fish species in different Wetland Protected Area types that can be used to inform conservation and management decisions for WPA.

Sediment monitoring for hydro-abrasive erosion: A field study from Himalayas, India

  • Rai, Anant Kr.;Kumar, Arun
    • International Journal of Fluid Machinery and Systems
    • /
    • v.10 no.2
    • /
    • pp.146-153
    • /
    • 2017
  • Sediment flow through hydropower components causes hydro-abrasive erosion resulting in loss of efficiency, interruptions in power production and downtime for repair/maintenance. Online instruments are required to measure/capture the variations in sediment parameters along with collecting samples manually to analyse in laboratory for verification. In this paper, various sediment parameters viz. size, concentration (TSS), shape and mineral composition relevant to hydro-abrasive erosion were measured and discussed with respect to a hydropower plant in Himalayan region, India. A multi-frequency acoustic instrument was installed at a desilting chamber to continuously monitor particle size distribution (PSD) and TSS entering the turbine during 27 May to 6 August 2015. The sediment parameters viz. TSS, size distribution, mineral composition and shape entering the turbine were also measured and analysed, using manual samples collected twice daily from hydropower plant, in laboratory with instruments based on laser diffraction, dynamic digital image processing, gravimetric method, conductivity, scanning electron microscope, X-ray diffraction and turbidity. The acoustic instrument was able to capture the variation in TSS; however, significant deviations were found between measured mean sediment sizes compared to values found in the laboratory. A good relation was found for turbidity ($R^2=0.86$) and laser diffraction ($R^2=0.93$) with TSS, which indicated that turbidimeter and laser diffraction instrument can be used for continuous monitoring of TSS at the plant. Total sediment load passed through penstock during study period was estimated to be 15,500 ton. This study shall be useful for researchers and hydropower managers in measuring/monitoring sediment for hydro-abrasive erosion study in hydropower plants.

A Study on the Remote Control for Exit Sign Using High Efficiency LED (고효율 LED를 이용한 유도등의 원격제어에 관한 연구)

  • 백동현;홍석표
    • Fire Science and Engineering
    • /
    • v.16 no.2
    • /
    • pp.1-7
    • /
    • 2002
  • In the normally, exit sign is always lighting on status by the connected to normal electrical source. So, there are happened to rise of the economical cost such as power consumption, maintenances and repair replacement of lamp etc. This paper are study on the new exit sign circuits by using high efficiency LED that is available for remote control and reduceible to power consumption, maintenance cost by the way of compensation fluorescent and incandescent lamps. As a results on the study, exit sign lamp is capable of control and supervisory in trigger angle by the remote control switch, widely and easily. And then, the response time was very fast in 600〔$\mu$s〕and also it can be find that the rising and fall time of oscillate circuit is maximum 200〔ns〕 as high sensitively. Finally, it obtain to the result that reducible of electrical power consumption and not required for replacement of lamp by using the high efficiency LED lighting source.

Economic Feasibility Study for Commercial Production of Bio-hydrogen (해양바이오수소개발 사업의 상업생산을 위한 예비경제성평가)

  • Park, Se-Hun;Yoo, Young-Don;Kang, Sung Gyun
    • Ocean and Polar Research
    • /
    • v.38 no.3
    • /
    • pp.225-234
    • /
    • 2016
  • This project sought to conduct an economic feasibility study regarding the commercial production of bio-hydrogen by the marine hyperthermophilic archaeon, Thermococcus onnurineus NA1 using carbon monoxide-containing industrial off-gas. We carried out the economic evaluation of the bio-hydrogen production process using the raw material of steel mill by-product gas. The process parameter was as follows: $H_2$ production rate was 5.6 L/L/h; the conversion of carbon monoxide was 60.7%. This project established an evaluation criterion for about 10,000 tonne/year. Inflation factors were considered as 3%. The operating costs were recalculated based on prices in 2014. The total investment required for development was covered 30% by capital and 70% by a loan. The operation cost for the 0.5-year test and integration, and the cost for the first three months in the 50% production period were considered as the working capital in the cost estimation. The costs required for the rental of office space, facilities, and other related costs from the construction through to full-scale production periods were considered as continuing expenses. Materials, energy, waste disposal and other charges were considered as the operating cost of the development system. Depreciation, tax, maintenance and repair, insurance, labor, interest rate charges, general and administrative costs, lubrication and miscellaneous expenses were also calculated. The hydrogen price was set at US$ 4.15/kg for the economic evaluation. As a result, the process was considered to be economical with the payback period of 6.3 years, NPV of 18 billion Won and IRR of 26.7%.

A Study on the Management and Utilization of Sub-Health Center in Rural area, Paraguay [1] - Focused on Limpio, Paraguay (파라과이 농촌지역 보건지소의 시설 관리 및 이용실태에 관한 연구[1] - 파라과이 림삐오시를 중심으로)

  • Kim, Ji Eon;Kim, Min Kyu;Nam, Eun Woo
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.26 no.2
    • /
    • pp.7-17
    • /
    • 2020
  • Purpose: The purpose of this study is to identify the operational status and current management of Sub-Health Centers in Limpio, Paraguay. Second, understanding the use of Sub-Health Centers and Perceptions of Sub-Health Centers in Limpio, Paraguay. Third, Providing policy implications for strengthening the Health Delivery System in Paraguay. Methods: The survey of the current status of sub-health centers in Limpio was conducted with observation and interview. Utilization of Sub-Health centers was analyzed in the 2018 Paraguay Community Health Survey. A face to face interview was conducted to complete a questionnaire and 831 samples were collected for the study. Results: In order to perform the normal function of the sub-health center, it will be necessary to allocate manpower that meets the standard. A common problem with sub-health centers in Limpio is that they have an environment vulnerable to rain. Currently, there are no health promotion and communicable disease management programs in sub-health center. Satisfaction of users about treatment, equipment, medicines and cleanleness of rooms. Implications: First, it is necessary to allocate human resources and organize spaces according to the standard. Second, there was a problem caused by moisture, and continuous maintenance and repair are required. Third, water and sewage related facilities must be safely improved to prevent contamination of groundwater. Forth, it is necessary to implement a program that fits the role of the sub-health center. Fifth, it is necessary to form a health delivery system considering the accessibility of residents. Finally, it is necessary to discuss the location of sub-health center considering travel time of Limpio residents.

RSPM : Storage Reliability Scheme for Network Video Recorder System (RSPM : NVR 시스템 기반의 저장장치 신뢰성 향상 기법)

  • Lee, Geun-Hyung;Song, Jae-Seok;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.47 no.2
    • /
    • pp.29-38
    • /
    • 2010
  • Network Video Recorder becomes popular as a next generation surveillance system connecting all cameras and video server in network environment because it can provide ease of installation and efficient management and maintenance. But in case of data damage, the storage device in traditional NVR has no recovery scheme and it is disabled in processing real-time requests. In this paper, we propose an Reliable Storage using Parity and Mirroring scheme for improving reliability on storage device and maintaining system on realtime. RSPM uses a Liberation coding to recover damaged multimedia data and dynamic mirroring to repair corrupted system data and to maintain real-time operation. RSPM using the Liberation code is 11.29% lesser than traditional file system and 5.21% less than RSPM using parity code in terms of loss rate of damaged multimedia data.

Deterioration Characteristics through Evaluating the Level of Deterioration of High-rise and High-density Apartments (고층고밀 아파트단지의 노후특성 평가 연구 - 1기 신도시 중 분당신도시의 아파트단지를 대상으로 -)

  • Cho, Sung-Heui;Lee, Tae-Kyung;Oh, Deog-Seong
    • Journal of the Korean housing association
    • /
    • v.20 no.6
    • /
    • pp.89-99
    • /
    • 2009
  • The purpose of this research is to determine the deterioration characteristics of high-rise and high-density apartment complexes in 1st period new towns in order to regenerate apartments as sustainable residential environments in Korea. For this purpose, the level of deterioration was evaluated by using 'evaluating indicators of the level of deterioration of high-rise and high-density apartments'. The deterioration characteristics were determined inclusively and concretely based on evaluation results. In addition, the deterioration level according to residents' awareness of the deterioration of their apartment was evaluated. This study was conducted by methods of field data collection, staff interview, field measurement, and resident survey according to the measurement of the evaluating indicators. And the re-organized questionnaire based on the evaluating indicators was utilized for a survey of resident's awareness. The results are as follows: In the physical dimensions of apartments, the deterioration characteristics included deteriorated equipment and a decline in structural performance due to the aging of the apartment, a shortage of parking spaces, and the low flexibility of the bearing wall structure, etc. In terms of the social dimensions, the apartments showed an increase in the number of elderly households, a shortage of community facilities, and a lack of the opportunity for community participation etc. In terms of the economic dimensions, the apartments showed limitations in maintenance & repair and a lack of environmentally friendly features.

A Study on Concept of the Mobile Access Part based on the ITU's Access Network Functional Model (ITU Access Network의 기능적 모형에 근거한 이동망의 가입자 접속 부문 정립에 관한 연구)

  • Kim, Moon-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.28 no.1A
    • /
    • pp.17-24
    • /
    • 2003
  • Access network is one of the most critical components of telecommunication networks. Essentially it provides the final connection through to the subscriber and at the same it is usually the most expensive component in terms of capital investment and ongoing cost of maintenance and repair In recent, various access technologies with broadband have been developed and also are emerging newly Comparing fixed access networks, the concrete concept as well as the scope of mobile access networks or parts has not been defined yet although it is caused by peculiarities of mobile network with mobility-guarantee technology, use of RF resource, fixed-exchange and transport networks This article examines the characteristics and detailed functions of BTS, BSC, MSC and other components in CDMA mobile network under the IS-95 A/B and cdma 2000-1x standards comparing the ITU's access network functional model From the systematic and functional perspectives, futhermore, an alternative definition for access parts of mobile network is proposed.

An Experimental Study on Thermal Damage and Spalling of Concrete Lining in Tunnel Fire (터널화재시 콘크리트 라이닝의 폭렬 및 화재손상에 관한 실험적 연구)

  • Kim, Heung-Youl;Kim, Hyung-Jun;Cho, Kyung-Suk;Lee, Jae-Sung;Kwan, Ki-Hyuk
    • Fire Science and Engineering
    • /
    • v.23 no.3
    • /
    • pp.110-120
    • /
    • 2009
  • In tunnel, though the frequency of fire occurrence is relatively lower than other structures, the characteristics of sealed space tends to cause the temperature to rapidly rise to more than $1000^{\circ}C$ within 5minutes after fire, which might eventually lead to a large fire that usually results in a loss of lives and the damage to the properties, not to mention a huge cost necessary for repair and maintenance after fire. We have developed various conditions of the heating furnace and the method to install a thermo couple within the furnace based on EFNARC and KS F 2257-1. Referring to tunnel fire scenarios, it clarified the heat transfer characteristics of concrete PC panel lining depending on fire intensity (ISO, $1^{\circ}C$/SEC, MHC, RWS), and to identify the range of thermal damage, the evaluation was carried out using ITA standard. As a result, 30mm under ISO fire condition, 20mm under $1^{\circ}C$/SEC, 100mm under MHC and 50mm under RWS were measured. And when it comes to spalling, 30mm was measured under RWS and MHC.

Policy Definition Language for Service Management in Mobile Environment (모바일 서비스관리를 위한 정책정의언어)

  • Ahn, Sung-Wook;Rhew, Yul-Sung
    • The KIPS Transactions:PartD
    • /
    • v.16D no.4
    • /
    • pp.561-570
    • /
    • 2009
  • In order to manage repair and maintenance efficiently in the mobile environment, the system structure to manage service as a policy and the policy description language are needed. This research defined the structure of PEP, which is the executioner of policy in the IETF policy framework, and proposed the policy description language which can be carried out under the PEP structure. The proposed policy description language derived demand matters based on documentary data and the characteristics of mobile and the policy information model was designed with the three stage approaches and was defined as policy description language. The three stage approaches are made up of the policy domain that decides the scope to which the policy applies, the policy rules which distinguish the kinds of policy application and control, and policy grammar which contextualizes the policy structure. In order to verify the efficiency of the policy description language, scenarios are defined with the policy description language and verified it by using policy tool and proved the expansive nature by comparing and analyzing other policy description language.