Fungi are organisms that must be monitored and controlled in order to preserve valuable paper records. They reduce the quality of paper records by degradation and/or discoloration. As an effort to understand fungal contamination in the National Archives of Korea, the concentration of fungi in the indoor air of the unsterilized record rooms has been reported. However, what species are present in the facilities is not much known. In the present study, we examined the fungi isolated from the National Archives of Korea and found among them that there are fungal species which are newly documented in Korea. They were identified based on morphological properties and nucleotide sequences analysis of the polymerase chain reaction-amplified the internal transcribed spacer region of rDNA, calmodulin gene, and beta-tubulin gene. We report Cladosporium parahalotolerans, Cladosporium subuliforme, Ochroconis mirabilis, Penicillium angulare, and Penicillium fundyense as new instances of fungal species in Korea. Among these five species, P. angulare is known to able to produce cellulase and O. mirabilis as an opportunistic pathogen of human and animals.
In order for records to be preserved for a long time without physical and chemical transformation, the preservation environment of the library is very important, and environmental problems must be improved through periodic investigation on the preservation environment. Against this background, this study derived fine dust (PM10) and ultrafine dust (PM2.5) concentration data for the libraries, hallways, and workrooms of the National Archives of Korea over two years. There was a difference in the concentration of fine dust and ultrafine dust among facilities, and there was a change in the concentration depending on the month. Both fine dust and ultrafine dust concentrations were present at less than 10 μg/m³ in the libraries. In the hallways, both fine and ultrafine dust concentrations were highest in July. In the workplaces, the monthly fluctuations in the concentration of fine dust and ultrafine dust were large. And the concentration of fine dust and ultrafine dust in the workplaces were higher than those in the library and hallways. Overall, the concentration of fine dust and ultra-fine dust was measured below the maintenance standards stipulated by the Indoor Air Quality Management Act of the Ministry of Environment of Korea in all the investigated facilities. The results of this study are expected to be used as fundamental information to manage the indoor air quality of the facilities of the National Archives.
Temperature, humidity, and fungal concentration were investigated during the period from May 2019 to August 2021 to obtain information on the indoor air quality in the facilities of the National Archive of Koea, located at Seongnam, Daejeon, and Busan, respectively. The temperature and humidity of the undisinfected libraries was properly maintained for the preservation of papepr records. The airborne fungal concentration differed among the libraries, changed according to the season, and increased especially between June and August. Similarily, the concentration of airborne fungi in the hallways adjacent to the libraries also fluctuated depending on the season and showed a tendency to rise in the months when the ourside temperature rose. In general, the concentration of airborne fungi in the hallways was somewhat higher than that of the libraries. Importantly, it was identified that the concentration of airborne fungi exceeded the recommended standard (500 CFU/m3) by the Ministry of Environment of Korea only in the workroom where the classification and condition inspection of undisinfected records imported from outside were performed. Investigation of airborne fungal concentration from May 2021 to August 2021 showed that the 24 undisinfected libraries in Seongnam, Daejeon, and Busan were all good at 100 CFU/m3 or less. The results of this study are expected to be used as basic data to manage the indoor environment of facilities in the National Archives.
In this study, a model to optimize residual chlorine concentrations in a water supply system was developed using a multi-objective genetic algorithm. Moreover, to quantify the effects of optimized residual chlorine concentration management and to consider customer service requirements, this study developed indices to quantify the spatial and temporal distributions of residual chlorine concentration. Based on the results, the most economical operational method to manage booster chlorination was derived, which would supply water that satisfies the service level required by consumers, as well as the cost-effectiveness and operation requirements relevant to the service providers. A simulation model was then created based on an actual water supply system (i.e., the Multi-regional Water Supply W in Korea). Simulated optimizations were successful, evidencing that it is possible to meet the residual chlorine concentration demanded by consumers at a low cost.
This research proposes an optimal flushing operation technique in an effort to prevent secondary water pollutions and accidents in aged pipes, and to improve the cleaning effect of unidirectional flushing. Water flow directions were analyzed using EPANET 2.0, while flushing and air scouring experiments in forward and reverse directions were performed in the field. In 42 experiments, average residual chlorine concentration and turbidity were improved after cleaning compared to before cleaning. It was found that even when the same cleaning method was used, further improvement of cleaning effect was possible by applying air injection and reverse direction cleaning techniques. By means of one-way ANOVA(Analysis of variance), it was also possible to statistically verify the need of actively utilizing air injection and reverse direction cleaning. Based on correlation between turbidity and TSS, the total amount of suspended solids removal was estimated for 874 flushing operations and 194 air scouring operations. The result showed that air scouring used more discharge water than flushing by an average of 4.9 m3 yet with larger amounts of suspended solids removal by an average of 145.9 g. The result of analysis on turbidity values from 887 flushing operations showed low cleaning effect of unidirectional flushing for the pipes with diameters over 300 mm. In addition, the turbidity values measured during cleaning showed an increasing tendency as pipe age increased. The methodology and results of this research are expected to contribute to the efficient maintenance and improvement of water quality in water distribution networks. Follow-up research involving the measurement of water quality at regular time intervals during cleaning would allow a more accurate comparison of discharge water quality characteristics and cleaning effects between different cleaning methods. To this end, it is considered necessary to develop a standardized manual that can be used in the field and to provide relevant trainings.
Water supply/intake pumps operation use 70~80% of power costs in water treatment plants. In the water treatment plant, seasonal and hourly differential electricity rates are applied, so proper pump scheduling can yield power cost savings. Accordingly, the purpose of this study was to develop an optimal water supply pump scheduling scheme. An optimal operation method of water supply pumps by using genetic algorithm was developed. Also, a method to minimize power cost for water supply pump operation based on pump performance derived from the thermodynamic pump efficiency measurement method was proposed. Water level constraints to provide sufficient disinfection performance in a clearwell and reservoirs were calibrated. In addition, continuous operation time constraints were calibrated to prevent frequent pump switching. As a result of optimization, savings ratios during 7 days in winter and summer were 4.5% and 5.1%, respectively. In this study, the method for optimal water pump operation was developed to secure disinfection performance in the clearwell and to save power cost. It is expected that it will be used as a more advanced optimal water pump operation method through further studies such as water demand forecasting and efficiency according to pump combination.
This study aimed to develop a method to optimize residual chlorine concentrations in the process of providing water supply. To this end, this study developed a model capable of optimizing the chlorine input into the clearwell in the purification plant and the optimal installation location of rechlorination facilities, and chlorine input. This study applied genetic algorithms finding the optimal point with appropriate residual chlorine concentrations and deriving a cost-optimal solution. The developed model was applied to SN purification plant supply area. As a result, it was possible to meet the target residual chlorine concentration with the minimum cost. Also, the optimal operation method in target area according to the water temperature and volume of supply was suggested. On the basis of the results, this study derived the most economical operational method of coping with water pollution in the process of providing water supply and satisfying the service level required by consumers in the aspects of cost effectiveness. It is considered possible to appropriately respond to increasing service level required by consumers in the future and to use the study results to establish an operational management plan in a short-term perspective.
BIM 설계에서 라이브러리의 구축 및 활용은 매우 중요하다. 기존 컨텐츠의 재활용이 가능하므로, 설계를 보다 효과적이 고 효율적으로 진행할 수 있다. 건축분야와 달리 토목분야, 특히 철도시설분야에서는 라이브러리의 구축 및 표준화가 미진하 다. 따라서 본 연구에서는 철도시설분야에 3차원 객체 라이브러리를 구축하고 표준화하고자 한다. 철도시설물 분류체계 및 관련도면을 수집 및 분석한다. 분석된 표준도면의 항목과 분류체계 항목을 매칭하였다. 각 항목별로 라이브러리가 필요한지 여부와 그럴 경우 어떤 소프트웨어가 적절한지를 검토하였다. 사용가능한 소프트웨어는 주로 Civil 3D와 Revit 등으로 나타 났다. 향후 이를 바탕으로 철도인프라 3차원 라이브러리의 속성 항목 및 명세서를 설계하고 라이브러리를 구축할 예정이다.
Using 3D based BIM(Building Information Modeling) enables a variety of construction simulations. The is no case to simulate BIM demonstration experiment on deeply immersed virtual reality environment in korea. This paper develops a multi screen based simulation system to enable 3D based immersed environment to diverse decision making and virtual construction simulation. In a developed simulation laboratory, we can carry out BIM drawing review, disaster evacuation simulation, constructability review on wild land and design urban planning using haptic device on 3-side space with 4K resolution . Also, It can review large amount of drawings without data conversion because of compatibility with BIM software.
BIM 설계에서 라이브러리의 구축 및 활용은 매우 중요하다. 기존 컨텐츠의 재활용이 가능하므로, 설계를 보다 효과적이 고 효율적으로 진행할 수 있다. 건축분야와 달리 토목분야, 특히 철도시설분야에서는 라이브러리의 구축 및 표준화가 미진하 다. 따라서 본 연구에서는 철도시설분야에 3차원 객체 라이브러리를 구축하고 표준화하고자 한다. 철도시설물 분류체계 및 관련도면을 수집 및 분석한다. 분석된 표준도면의 항목과 분류체계 항목을 매칭하였다. 각 항목별로 라이브러리가 필요한지 여부와 그럴 경우 어떤 소프트웨어가 적절한지를 검토하였다. 사용가능한 소프트웨어는 주로 Civil 3D와 Revit 등으로 나타 났다. 향후 이를 바탕으로 철도인프라 3차원 라이브러리의 속성 항목 및 명세서를 설계하고 라이브러리를 구축할 예정이다
For the asset management of a water pipe network, it would be necessary to understand the extent of the maintenance cost required for the water pipe network for the future. This study would develop a method to draw the optimum cost required for the maintenance of the water pipe network in waterworks facilities to maintain the aim revenue water ratio and to achieve the target revenue water ratio, considering the water service providers’ waterworks condition and revenue water ratio comprehensively. This study conducted a survey with 96 water service providers as of the early 2015 and developed models to estimate the optimum maintenance cost of the water pipe network, considering the characteristics of the water service providers. Since the correlation coefficient of all the developed models was higher than 0.95, it turned out that it had significant reliability, which was statistically significant. As a result of applying the developed models to the actual water service providers, it was drawn that increasing revenue water ratio to more than a certain level can reduce the maintenance cost of the water pipe network by a great deal. In other words, it is judged that it would be the most efficient to secure the reliability of waterworks management by increasing the short-term revenue water ratio to more than a certain level and gradually increase the revenue water ratio from the long-term perspective. It is expected that the proposed methodology proposed in this study and the results of the study will be used as a basic research for planning the maintenance of water pipe network or establishing a plan for waterworks facilities asset management.
본 연구는 미래친환경 소자로 대두되는 LED(발광다이오드, Light Emitting Diode)광원을 느타리(Pleurotus ostreatus) 재배법에 적용하여 최적화된 시스템을 개발하고자 수행하였다. 느타리의 LED광원별 생육적 특성을 규명하기 위하여 대조구 1종(관행재배: 삼파장 형광등)과 실험구 2종(LED 적색광 및 청색광)으로 시험한 결과는 다음과 같다. 초발이 소요일수는 대조구 6일, 적색광(660nm) 5일, 청색광(450nm) 5.5일로 나타나 대조구보다 실험구에서 빠르게 나타났으며, 청색광보다는 적색광에서 0.5일 단축되었다. 생육일수는 대조구 8일, 적색광 및 청색광에서 7일로 대조구보다는 실험구에서 우수하게 나타났다. 또한 색감 도 대조구보다 실험구에서 우수하게 나타났고 적색광보다는 청색광에서 가장 우수하였다. 봉지당 수량성은 대조구 216.5g, 적색광 217.2g, 청색광 216.2g으로 대조구와 실험구간 큰 차이점을 나타나지 않았다. 이상 전체 재배일수는 대조구 15일, 적색광 14일, 청색광 14.5일로 대조구보다 실험구에서 빠른 재배일수를 보였다. 종합적으로 LED광원을 사용한 느타리의 생육적 특성은 초발이, 생육일수, 색감, 전체 재배일수 등에서 대조구(관행재배법)보다 우수하였다.