• Title/Summary/Keyword: detention

Search Result 303, Processing Time 0.026 seconds

Study of analytical probabilistic models for urban flood control detention facilities in Korea (도시 홍수 저감 저류시설 설계를 위한 해석적 확률모형 연구)

  • Lee, Moonyoung;Jeon, Seol;Kim, Si Yeon;An, Heejin;Jung, Kichul;Park, Daeryong
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2021.06a
    • /
    • pp.298-298
    • /
    • 2021
  • 본 연구에서는 국내 6개 지역 서울, 강릉, 대전, 광주, 부산, 제주의 30년 치 시강우 자료에 해석적 확률모형(Analytical Probabilistic Models) 방법을 적용하여 도시 홍수 저감을 목적으로 하는 저류시설 설계를 위한 유출량 예측 정도를 지역별로 비교하고자 하였다. 강우 사상 분포의 해석적 확률모형을 적용하기 위해 무강우 시간을 결정하여 독립 호우를 결정하는데, 자기상관계수와 변동계수를 활용한 무강우 지속시간의 산정(IETD, Interevent Time Definition) 방법을 사용하였다. 해석적 확률모형인 유출량의 확률밀도함수(PDF, Probability Density Function)를 유도하기 위해서 불투수 지역과 투수 지역의 영향을 고려하여 유출계수를 적용하는 강우-유출 관계를 가지고 유출량을 정의하였다. 강우량, 강우 지속시간, 무강우시간과 같은 강우특성은 1변수 지수함수의 PDF를 따른다고 가정하였다. 확률모형 방법의 적합성을 판단하기 위해 결정된 IETD에 따라 각 지역별로 실제 강우 사상을 해석적 모델과 연속모의실험인 SWWM(Storm Water Management Model)에 적용하여 불투수율에 따른 유출량을 산정하였다. 각 방식으로 얻은 유출량 결과는 모든 지역에서 매우 유사하게 나타났고 결론적으로 우리나라에서 도시 홍수 저감을 위한 저류시설의 계획과 설계에 확률모형 방법이 적용 가능하다는 것을 확인할 수 있었다.

  • PDF

Application and Maintenance Strategies for Eco-Friendly Facilities in Landscape Trees Nurseries

  • Young Sun Seok;O Man Kwon;Yun Eui Choi
    • Journal of Forest and Environmental Science
    • /
    • v.40 no.2
    • /
    • pp.151-165
    • /
    • 2024
  • Recently, as the number of landscaping plant nurseries have increased, environmental problems such as topographical damage due to indiscriminate changes in land use, increased non-point pollution, and increased impervious areas are also occurring. In this study, we propose eco-friendly facilities and a detailed maintenance manual that can enhance the eco-friendliness and scenic beauty of landscaping plant nurseries that are increasingly located near cities. By exploring previous reports on eco-friendly facilities and related laws, we cataloged the types of eco-friendly facilities, and by referring to examples of eco-friendly facilities introduced in overseas cases and the environmental functions of agriculture, we cataloged the types of eco-friendly facilities suitable for introduction in plant nurseries. The selected facilities are rain gardens, tree boxes, vegetated filter beds, bio-retention, infiltration trench, infiltration tanks, permeable pavements, and sand filtration systems. The maintenance tasks of eco-friendly facilities were categorized and management plans were proposed, which is expected to be utilized as a basic data to prepare eco-friendly space planning and operation management plans when creating a landscape plant nurseries in the future.

Comparison of Food Supply Status of Korean(Chosun) and Taiwan Prisoners under the Period of Japanese Rule with That of French and German Prisoners in 1920~1930′s (일제하(1920~30연대) 조선과 대만 그리고 프랑스와 독일 수형인의 식품공급상황 비교)

  • 허채옥
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.13 no.4
    • /
    • pp.267-283
    • /
    • 2003
  • This study reviewed the prisoners' dietary lift status under the world panics and Japanese food shortage based on the data of the 1920~1930's prisons' main dish supplies in Chosun, Shinchu boys' prison in Taiwan, Franue correction center in France and Moabit detention house in Germany. 1. The status of main dish food supply of Chosun prisons in 1920~1930's was as follows: 1) Meals were provided with 12 rates depending on the working activities. There were big differences in energy supply between 1$^{st}$ rate of 6045.0 ㎉ in the Mockpo prison and 12$^{th}$ rate of 1855.8 ㎉ in the Masan prison in accordance with the grain supply ratio and the diet rates. 2) The average ratio of energy provided with protein, fat and carbohydrate(PFC ratio) was 20.0: 20.2: 59.8. The supplies of protein and fat were relatively high because main dish was mostly composed of soybean. The soybean was used in 20 ~60% of main dish in prisons except Gaesung. 3) It was estimated that PFC ratio(8.3: 8.1 : 83.6) in Gaesung boys' prison was not appropriate for growing boys because the soybean supply was low. 2. The overall comparison of nutrition supply of prisons in Chosun, Taiwan, France and Germany was as follows: 1) The daily supplies of energy in Keongsung prison was 3966.5 ㎉, of which the PFC ratio was 18.9: 16.6: 64.5. This showed that the PFC ratio seemed to be balanced, even though the total amount of energy is too high and the ratios of protein and fat were somewhat high and somewhat low, respectively. 2) The main dish of the Taiwan boys' prison was provided with 6 rates and the side dish in the from of weekly cycle menu. The energy intakes from 1$^{st}$ rate of 2862.9 ㎉ to 6$^{th}$ rate of 1388.9 ㎉ were not quite enough for growing boys. It was estimated that the amounts of protein and fat taken were small but the quality was not that bad because animal protein such as protein small fish and fried tofu were supplied. 3) In the French Frenue correction center and the German Moabit detention house, the daily total amounts of energy were 2771.3 ㎉ and 2678.7 ㎉, respectively, which was estimated as appropriate compared with standard energy amount of 3000 ㎉ at that time and the current energy RDA of 2500 ㎉ for adult. The ratio of PFC was 16.2: 12.0: 71.8 in Frenue correction center and 12.4: 14.3: 73.3 in Moabit detention house, which showed that the amount of fat was slightly lacked. From this study, it was suggested that the prisons in Chosun and Taiwan under the Japanese rule and European prisons after the world panic were making an efforts to supply prisoners the appropriate amount of energy. The only question remains is that this data may be from only the food supply plan not from the data the prisoners took in real.eal.

  • PDF

The Evaluation of Food Service Menus in an Immigration Detention Center (외국인 보호소 급식 식단 품질에 대한 인식 및 만족도)

  • Kim, Hye-Jin;Kim, Woon Joo;Lee, Young Eun
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.42 no.2
    • /
    • pp.286-305
    • /
    • 2013
  • The purpose of this study was to investigate the recognition and satisfaction with the menu quality of food services in an immigration detention center. The survey was conducted from January 22, 2010 to April 22, 2010 by questionnaires. A survey with 265 respondents was conducted and data analyzed by the SAS Program. In analyzing leftovers, the most common was kimchi (37.61%), followed by breads (21.52%), and beans/bean curd (17.99%). The common cause for leftover were undesirable taste (31.84%), sickness or a lack of desire for eating (19.85%). In terms of cooking methods, stir-frying, broiling, and frying were highly preferred to steaming, boiling, and salting. In the analysis of preferences in the taste and satisfaction of food service, there were significant differences in hot, sour, bitter, and light tastes (p<0.05, p<0.01, p<0.001). Satisfaction was low with hot and light tastes, whereas sour and the bitter tastes showed a high degree of satisfaction. In the opinions for quality improvement, most immigrants wanted a tastier food supply (58.69%), a diverse food supply (40.54%), and clean utensils (36.68%). In the analysis of the gap between importance and performance, food taste, variety, and sanitation were recognized as poorly performed, causing major dissatisfaction with the food. The overall satisfaction score was 'average' (3 points out of 5 points) with 3.26 points. The satisfaction score showed insignificant difference depending on religions and duration of stay in Korea, but showed significant differences depending on nationality (p<0.001).

Research on improvement of water purification efficiency by porous concrete using bio-film (생물막을 이용한 다공성 콘크리트의 수질정화 효율 개선에 대한 연구)

  • Kim, Tae-Hoon;Li, Feng-Qi;Ahn, Tae-Woong;Choi, I-Song;Oh, Jong-Min
    • Journal of Environmental Impact Assessment
    • /
    • v.20 no.6
    • /
    • pp.815-821
    • /
    • 2011
  • This study aims to estimate the biological decomposition capacity of MPC(Microorganism Porous-Concrete). MPC has specific surface area formed by inside pores, and bio compound was added to those pores to reduce pollutants loading. To evaluate the water purification capacity of MPC, we carried out the comparative studies using different media types [GPC(General Porous-concrete), CPC(Compound porous-concrete), LPC(Lightweight aggregate porous-concrete)] under the condition of CFSTR, and different retention times (30, 60 and 120 min). We also estimated the purification capacity of MPC under different concentrations of pollutant loadings. The MPC showed higher efficiency in water purification function than other conventional porous concretes with efficient decrease rates of SS, BOD, COD, and nutrient concentrations. In the comparison experiment for different retention times, MPC showed the highest removal efficiency for all tested pollutants in the longest retention time(120 min). In the long period test, the removal efficiencies of MPC concrete were high until 100 days after the set up of the operation, but began to decrease. Outflow flux was invariable compared with inflow flux so that extra detention time for media fouling such as back washing is not needed. But the results suggested that appropriate management is necessary for long-term operation of MPC. As the final outcome, MPC using bio organisms is considered to be efficient for stream water purification when they used as substrates for artificial river structure.

Flood Inundation Analysis in Urban Area Using XP-SWMM (XP-SWMM 모형을 이용한 도심지역 침수해석)

  • Kim, Jinsu;Lee, Wonho
    • Journal of the Korean GEO-environmental Society
    • /
    • v.16 no.1
    • /
    • pp.29-36
    • /
    • 2015
  • Current domestic research is to demonstrate the effectiveness and efficiencies of flood prevention measures through one-dimensional numerical analysis and this study's object is to help water managers to make the efficient decisions by applying the two-dimensional urban run off model XP-SWMM model in the flooded area and comparing with the flood prevention measures. Statistics were analyzed, based on the data collected from Cheongju Weather Service from 1967 to 2011 for 45 years. 50 years Flood frequency simulations of water flow capacity analysis of the target area for flooded areas $539,548m^2$, inundation depth 1.0 m, was analyzed by inundation time of 48 minutes. When comparing with the constructions of bypass road and underground storage facilities to increase the water flow capacity of A1 small drainage areas as flood protection, if you install a batching target underground detention basin with a capacity of $13,500m^3$, it is expected that the flood by rainfall with frequency of 50 years will be resolved completely. In preparation for extreme weather in the future flood mitigation measures, underground storage tank installation is considered a better efficient way.

Comparative Study of the System for Decentralized Rainwater Management in Korea and Germany (한국과 독일의 분산식 빗물관리를 위한 제도 비교 연구)

  • Han, Young-Hae;Lee, Tae-Goo
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.34 no.4 s.117
    • /
    • pp.84-95
    • /
    • 2006
  • This study begins by examining the reason for the lack of urban planning that takes the water cycle into consideration. While there are institutions that support environmentally friendly development or smooth water circulation, these designs are not reflected in planning nor in the real world. After reviewing foreign case studies, policy suggestions and possible policy implications for Korea are derived. In Korea, there is not a sufficient level of relevant laws or institutions systematically established to make it possible to deal with rainwater in a decentralized way. Instead, facility standards or guidelines are considered separately for the control of water and for preventing natural disasters. And even though an environmentally friendly approach is stipulated in relevant laws in terms of spatial planning, there are no planning systems or implementation tools to actualize this kind of approach. The factors that make decentralized rainwater management possible in urban planning are analyzed based on the case study of Germany. Germany requires developers to plan in order to achieve ecological urban development. In addition, as a detailed implementation tool to promote conservation of the water cycle, the law provides for various kinds of measures such as restrictions on the proportion of impervious surface area according to the use of the land, required compensation measures for environmental degradation following development, introduction of a fee for rainwater runoff and the establishment of ecological landscape planning. The actual reason these measures can be implemented however is the provision of planning guidelines and design criteria for rainwater utilization, absorption and containment, and the construction of a database for various environmental information.

NO3-N Removal of A Reed Wetland Cell Constructed for Purifying Effluent from A Night Soil Treatment Plant During Its Initial Operating Stage (분뇨처리장 방류수정화 갈대습지셀의 초기운영단계 질산성질소 제거)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.7 no.5
    • /
    • pp.100-106
    • /
    • 2004
  • $NO^3$-N removal was examined from July 2002 to December 2002 of a surface-flow constructed treatment wetland cell, which was a part of a treatment wetland system composed of four wetland cells and one distribution pond. The system was established on rice paddy near the Kohung Estuarine Lake located at the southern part of the Korean Peninsula. The lake and the paddy were formed by a salt marsh reclamation project. Effluent from a secondary-level treatment plant was funneled into the system. The investigated cell was created in June 2002. Its dimensions were 87 m in length and 14 m in width. It had an open water zone at its center, which was equivalent to 10 percent of its total area. Reeds(Phragmites australis) were transplanted from natural wetlands into the cell and their stems were cut at about 40 cm height from their bottom ends. Average 25 $m^3$/day of effluent from the plant was funneled into the cell by gravity flow and average 24.2$m^3$/day of its treated effluent was discharged into the Sinyang Stream flowing into the lake. Its water depth was maintained about 0.2 m and its hydraulic detention time averaged 5.2 days. The average height of the reed stems was 45.2 cm in July 2002 and 80.5 cm in September 2002. The number of stems averaged 40.3 stems/$m^2$ in July 2002 and 74.5 stems/$m^2$ in September 2002. The reeds were established initially well. $NO_3$-N loading rate of influent and effluent averaged 173.7 and $93.5mg/m2{\cdot}day$, respectively. Removal of $NO_3$-N averaged $80.2mg/m2{\cdot}day$ and its removal rate by mass was about 50 %. Considering the initial operation of the cell and the inclusion of the cold months of November and December in the analysis period, the $NO_3$-N removal rate was good.

Total Phosphorus Removal Rate of a Subsurface-Flow Wetland System Constructed on Floodplain During Its Initial Operation Stage (고수부지에 조성한 수질정화 여과습지의 초기운영단계 총인 제거)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.6 no.6
    • /
    • pp.49-55
    • /
    • 2003
  • Total phosphorous removal rate was examined of a subsurface-flow treatment wetland system which was constructed on floodplain in the down reach of the Kwangju Stream in Korea from May to June 2001. Its dimensions were 29 meter in length, 9 meter in width and 0.65 meter in depth. A bottom layer of 45 cm in depth was filled with crushed granite with about 15~30 mm in diameter and a middle layer of 10 cm in depth had pea pebbles with about 10 mm in diameter. An upper layer of 5 cm in depth contained course sand. Reeds(Phragmites australis) were transplanted on the surface of the system. They were dug out of natural wetlands and stems were cut at about 40 cm height from their bottom ends. Water of the Kwangju Stream flowed from a submerged dam into it via a pipe by gravity flow and treated effluent was funneled back into the Stream. The number of reed stems increased from 80 stems/$m^2$ in July 2001 to 136 stems/$m^2$ in September 2001. The hight of stems was 44.2 cm in July 2001 and 75.3 cm in September 2001. The establishment of reeds at early operating stage of the system was good. Volume and water quality of inflow and outflow were investigated from July 2001 through December 2001. The average inflow was 40 $m^3$/day and hydraulic detention time was about 1.5 days. The concentration of total phosphorous n influent and effluent was 0.83 and 0.33 mg/L, respectively. The removal rate of total phosphorous averaged about 60%. The removal efficiency was slightly higher, compared with that of subsurface-flow wetlands operating in North America, whose retention rate of total phosphorous was reported to be about 56%. The good abatement rate could be attributed to sedimentation of particle phosphorous in pores of the media and adsorption of phosphorous to the biofilm developed on the surface of them. Increase of standing density of reeds within a few years will develop root zones which may lead to increment in the phosphorous retention rate.

Characteristics of Coagulants Distribution by the Pumping Rate in Pump Diffusion Mixer (Pump Diffusion Mixer에서 압력수량에 따른 응집제 확산분포 특성)

  • Park, Youngoh;Kim, Ki-Don;Park, No-Suk;Lim, Jae-Lim;Lim, Kyung-Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.22 no.1
    • /
    • pp.65-71
    • /
    • 2008
  • This study collected the latest 30-year (1976~2005) continuous rainfall data hourly recorded at 61 meterological observatories in Korea, and the continuous rainfall data was divided into individual rainfall events. In addition, distribution charts of average rainfall event-depth were created to facilitate the application to the overflow risk-based design of detention storage basin. This study shows that 4 hour is appropriate for SST (storm separation time) to separate individual rainfall events from the continuous rainfall data, and the one-parameter exponential distribution is suitable for the frequency distribution of rainfall event depths for the domestic rainfall data. The analysis of the domestic rainfall data using SST of 4 hour showed that the individual rainfall event was 1380 to 2031 times, the average rainfall event-depth was 19.1 to 32.4mm, and ranged between 0.877 and 0.926. Distribution charts of average rainfall event-depth were created for 4hour and 6 hour of SST, respectively. The inland Gyeongsangbuk-do, Western coastal area and inland of Jeollabuk-do had relatively lower average rainfall event-depth, whereas Southern coastal area, such as Namhae, Yeosu, and Jeju-do had relatively higher average rainfall event-depth.