• 제목/요약/키워드: Changes of state of water

검색결과 362건 처리시간 0.03초

Effect of Rainfall Patterns on the Response of Water Pressure and Slope Stability Within a Small Catchment: A Case Study in Jinbu-Myeon, South Korea

  • Viet, Tran The;Lee, Giha;Oh, Sewook;Kim, Minseok
    • 한국지반환경공학회 논문집
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    • 제17권12호
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    • pp.5-16
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    • 2016
  • This study aims to assess the influence of rainfall patterns on shallow landslides initiation. Doing so, five typical rainfall patterns with the same cumulative amount and intensity components comprising Advanced (A1 and A2), Centralized (C), and Delayed (D1 and D2) were designed based on a historical rainstorm event in Jinbu. Mt area. Those patterns were incorporated as the hydrological conditions into the Transient Rainfall Infiltration and Grid-based Regional Slope-stability Model (TRIGRS) to assess their influences on groundwater pressure and changes in the stability of the slope. The results revealed that not only the cumulative rainfall thresholds necessary to initiate landslides, but also the rate at which the factor of safety decreases and the time required to reach the critical state, are governed by rainfall patterns. The sooner the peak rainfall intensity, the smaller the cumulative rainfall threshold, and the shorter the time until landslide occurrence. Left-skewed patterns were found to have a greater effect on landslide initiation. Specifically, among five rainfalls, pattern (A1) produced the most critical state. The severity of response was followed by patterns A2, C, D1, and D2. Our conclusion is that rainfall patterns have a significant effect on the cumulative rainfall threshold, the build-up of groundwater pressure, and the occurrence of shallow landslides.

변온저장(變溫貯藏)에 따른 백미(白米)의 품질변화(品質變化)에 관(關)한 반응속도론적(反應速度論的) 연구(硏究) -1. 유효(有效) Lysine의 감소(減少)에 관(關)하여- (Kinetics of Quality Changes in Rice Stored under the Temperature Fluctuation -1. Loss of Available Lysine in Polished Rice-)

  • 김무남;강문선;전순실
    • 한국식품영양과학회지
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    • 제13권2호
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    • pp.181-187
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    • 1984
  • Lysine is known as a limiting amino acid in rice. In addition, it is considered to be important in that it is easily non-activated by the browning reaction during processing or storage. The present study was designed to utilize a kinetic approach to analyse the effect of temperature and water activity on available lysine loss in rice. Simplified kinetic models were used to obtain the various kinetic parameters for available lysine loss in rice subjected to accelerated shelf-life tests (ASLT). These kinetic parameters were then used to predict protein quality loss under the non-steady state storage. The predicted losses were compared to the actual losses. As expected, available lysine loss was increased with increased temperature and water activity. The activation energies and $Q_{10}$ values for available lysine loss ranged from 4.03 to 5.10 Kcal/ mole and 1.22 to 1.27, respectively, The shelf-lives at $25^{\circ}C$, the time to reach 25% loss of the available lysine, which was derived from the accelerated shelf-life tests showed 67 to 107 days according to $a_w$'s. The amount of loss for the fluctuating condition was greater than that occurring at the mean temperature of $45^{\circ}C$. Actually, the differences in effective temperature for the fluctuating storage were between about 4 and $6^{\circ}C$. In predicting the extent of loss using constant state data, the predicted shelf-lives were 2 to 7 days shorter than the actual storage values.

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DNCB로 아토피가 유도된 NC/Nga생쥐에서 천연 탄산 온천수의 온도별 항아토피 효과 (The anti-atopic effect of natural carbonated hot spring water on DNCB-induced NC/Nga mice under different temperature)

  • 고가연;박정환;장순우;김윤하;박정미;안택원
    • 혜화의학회지
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    • 제25권1호
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    • pp.119-132
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    • 2016
  • Objectives : The aim of this study is to investigate the effect of natural carbonated hot spring water (NCHW) on DNCB-induced NC/Nga mice, an atopic dermatitis (AD) model. Methods :At first, NC/Nga mice were prepared and induced to have atopic lesion on their back skin by dinitrochlorobenzene (DNCB). They swam for 20 minutes everyday in tanks where the one is filled with $28^{\circ}C$ NCHW, the other is with $25^{\circ}C$ carbonated hot spring water and another is with artificial carbonated hot spring water (ACHW). After 3 weeks, We assessed the skin clinical score and macroscopic appearance, total IgE, IgG1 levels, WBC differential counting, IFN-${\gamma}$, IL-4, IL-13, TNF-${\alpha}$ production levels and histological changes. Results : There are meaningful results of improving atopic lesion-state by relieving the count of total IgE, IgG1 levels, WBC differential counting, IFN-${\gamma}$, IL-4, IL-13, TNF-${\alpha}$ production levels and recovering skin clinical score in the group with $28^{\circ}C$ NCHW in comparison with the other groups. Conclusions : The NCHW may have potential as an effective treatment for atopic dermatitis.

Investigating the Impact of Best Management Practices on Nonpoint Source Pollution from Agricultural Lands

  • 최예환
    • 한국농공학회지
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    • 제32권E호
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    • pp.1-19
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    • 1990
  • Abstract Over the last several decades, crop production in the United States increased largely due to the extensive use of animal waste and fertilizers as plant nutrient supplements, and pesticides for crops pests and weed control. Without the application of animal waste best management, the use of animal waste can result in nonpoint source pollution from agricultural land area. In order to increase nutrient levels and decrease contamination from agricultural lands, nonpoint source pollution is responsible for water quality degradation. Nonpoint source pollutants such as animal waste, ferilizers, and pesticides are transported primarily through runoff from agricultural areas. Nutrients, primarily nitrogen and phosphorus, can be a major water quality problem because they cause eutrophic algae growth. In 1985, it was presented that Watershed/Water Quality Monitoring for Evaluation BMP Effectiveness was implemented for Nomini Creek Watershed, located in Westmoreland County, Virginia. The watershed is predominantly agricultural and has an aerial extent of 1505 ha of land, with 43% under cropland, 54% under woodland, and 3% as homestead and roads. Rainfall data was collected at the watershed from raingages located at sites PNI through PN 7. Streams at stations QN I and QN2 were being measured with V-notch weirs. Water levels at the stream was measured using an FW-l Belfort (Friez FWl). The water quality monitoring system was designed to provide comprehensive assessment of the quality of storm runoff and baseflow as influenced by changes in landuse, agronomic, and cultural practices ill the watershed. As this study was concerned with the Nomini Creek Watershed, the separation of storm runoff and baseflow measured at QNI and QN2 was given by the master depletion curve method, and the loadings of baseflow and storm runoff for TN (Total Nitrogen) and TP (Total Phosphorus) were analyzed from 1987 through 1989. The results were studied for the best management practices to reduce contamination and loss of nutrients, (e.g., total nitrogen and total phosphorus) by nonpoint source pollution from agricultural lands.

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비모수적 추계학적 일 강우 발생기 기반의 빗물이용시설 신뢰도 평가모형의 부산광역시 해운대 신시가지 적용 (Application of Rainwater Harvesting System Reliability Model Based on Non-parametric Stochastic Daily Rainfall Generator to Haundae District of Busan)

  • 최치현;박무종;백천우;김상단
    • 한국물환경학회지
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    • 제27권5호
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    • pp.634-645
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    • 2011
  • A newly developed rainwater harvesting (RWH) system reliability model is evaluated for roof area of buildings in Haeundae District of Busan. RWH system is used to supply water for toilet flushing, back garden irrigation, and air cooling. This model is portable because it is based on a non-parametric precipitation generation algorithm using a markov chain. Precipitation occurrence is simulated using transition probabilities derived for each day of the year based on the historical probability of wet and dry day state changes. Precipitation amounts are selected from a matrix of historical values within a moving 30 day window that is centered on the target day. Then, the reliability of RWH system is determined for catchment area and tank volume ranges using synthetic precipitation data. As a result, the synthetic rainfall data well reproduced the characteristics of precipitation in Busan. Also the reliabilities of RWH system for each of demands were computed to high values. Furthermore, for study area using the RWH system, reduction efficiencies for rooftop runoff inputs to the sewer system and potable water demand are evaluated for 23%, 53%, respectively.

Consumption of Water-Soluble Egg Yolk Extract on Growth Rate, Changes in Blood Cholesterol Levels, and Immune Modulation in BALB/c Mice

  • Lee, Won-Young;Lee, Ran;Kim, Hee-Chan;Lee, Kyung-Hoon;Noh, Kyung Sook;Kim, Hyoun Wook;Kim, Ji-Hyuk;Ahn, Dong-Uk;Jang, In-Surk;Jang, Aera;Lee, Hoon-Taek;Song, Hyuk
    • 한국축산식품학회지
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    • 제33권5호
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    • pp.587-594
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    • 2013
  • Egg consumption has been limited to avoid cardiovascular diseases such as atherosclerosis and hyperlipidemia, because the yolk contains high levels of cholesterol. This study was conducted to evaluate the effect of the water-soluble component of egg-yolk on the growth efficiency, immune modulation, and changes in serum lipid levels in BALB/c mice. A total 5 wk old 120 BALB/c male mice were divided into 4 groups and were fed 0, 2, 10, and 20 mg/d water-soluble egg yolk extract (WSEYE) for 5 wk. Water-soluble egg yolk extract (WSEYE) uptake resulted in a significant reduction in daily weight gain and feed efficiency rate (FER). The mouse groups treated with 2 and 20 mg/d WSEYE showed a significant increase in populations of monocytes at the third wk and B-lymphocyte activity at the fifth wk. In addition, WSEYE uptake did not influence serum immunoglobulin E levels. In serum lipid-profile studies, treatment of WSEYE did not alter total cholesterol and low-density lipoprotein levels; however, blood triglyceride levels were significantly diminished in mice treated with 2 mg/d at the third wk (p<0.05), and the level of high-density lipoprotein was significantly increased in the mice group treated with 2 and 10 mg/d WSEYE after 5 wk (p<0.05). Taken together, the data demonstrate the beneficial effects of WSEYE in the diet on immune modulation and serum lipid profiles in mouse models; therefore, this study suggests that ingestion of water-soluble fraction of egg yolk might not be related to the increased risk of heart disease, but can be an excellent candidate for maintaining health.

대수층 축열 에너지 활용 모델의 온도 분포 시뮬레이션 연구 (A study of the simulation of thermal distribution in an aquifer thermal energy storage utilization model)

  • 심병완;송윤호
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.697-700
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    • 2005
  • Aquifer Thermal Energy Storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop an ATES system which has certain hydrogeological characteristics, understanding of the thermo hydraulic processes of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermo hydraulic transfer for heat storage is simulated using FEFLOW according to two sets of pumping and waste water reinjection scenarios of heat pump operation in a two layered confined aquifer. In the first set of model, the movement of the thermal front and groundwater level are simulated by changing the locations of injection and pumping well in seasonal cycle. However, in the second set of model the simulation is performed in the state of fixing the locations of pumping and injection well. After 365 days simulation period, the temperature distribution is dominated by injected water temperature and the distance from injection well. The small temperature change is appears on the surface compared to other slices of depth because the first layer has very low porosity and the transfer of thermal energy are sensitive at the porosity of each layer. The groundwater levels and temperature changes in injection and pumping wells are monitored to validate the effectiveness of the used heat pump operation method and the thermal interference between wells is analyzed.

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Changes in Habitat Use by Female Japanese Pipistrelles (Pipistrellus abramus) during Different Stages of Reproduction Revealed by Radio Telemetry

  • Chung, Chul Un;Kim, Sung Chul;Jeon, Young Shin;Han, Sang Hoon
    • 한국환경과학회지
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    • 제26권7호
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    • pp.817-826
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    • 2017
  • We analyzed how foraging area use changed in female Pipistrellus abramus during the breeding season. Radio tracking was used to follow 12 female P. abramus in Gyeongju City, from 2013 to 2015. We followed three bats in each of four stages of reproduction: early pregnancy, late pregnancy, lactation, and post-lactation. Our data showed that the usable area of a foraging site and the area that was actually used by bats in that site were different, and foraging site use also differed according to stage of reproduction. The bats used arable land the most, with use rates of 57%, 40.4%, and 73.2% during early pregnancy, late pregnancy, and lactation, respectively. Bats in a post-lactation state did not use arable areas at all and instead foraged over bodies of water 90% of the time. There was no difference in the use of each foraging environment between bats in early pregnancy and late pregnancy. However, bats in late pregnancy and those that were lactating did use arable land to different extents, and bats that were lactating and those that were post-lactation also used arable land and bodies of water to different extents.

Overfishing and recent risk for collapse of fishery in coastal Mediterranean lagoon ecosystem (Karavasta lagoon, southeastern Adriatic sea)

  • Spase Shumka;Yukio Nagahama;Sarjmir Hoxha;Koji Asano
    • Fisheries and Aquatic Sciences
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    • 제26권4호
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    • pp.294-303
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    • 2023
  • Beside that the fish species and their sub-populations are highly important as a keystone species in the coastal and marine ecosystem, there are very few studies on their presence, distribution and temporal variations within and around the lagoon ecosystems in Albania. This paper provides an updated review on the life cycle, fishery, exploitation state and management of the main species that are subject of commercial fishing in the Karavasta lagoon, southeastern Adriatic coast of Albania. Due to the fact that lagoons represent a continuum between continental and marine aquatic ecosystems they play a crucial role in species life cycles. Further on in the circumstances of rapid utilizations and environmental changes, anomalies in salinity and temperatures, accelerated anthropogenic influences their rate of vulnerability is highly increased. Following the requirements of the Water Framework Directive, transitional water, coastal lagoons and estuaries there is a need for urgent monitoring and management approaches. The commercial species include: European eel (Anguilla anguilla), species of Family Mugilidae (Mugil cephalus, Liza ramada, Liza salienes and Chelon labrosus), Seabream (Sparus aurata), Seabass (Dincentrarchus labrax), etc. Fish productivity is oscillating from maximum value of 61.95 kg/ha is recorded in period of 1975-80 and lower value of 31 kg/ha in year 2020. Our study highlights importance of fish and fishery long-term monitoring, and contributes to understand the driving factors in productivity, migration patterns and species ecology in the vital coastal ecosystems.

이중확산의 영향을 받는 염수침입의 혼합과정 연구 (Mixing Process of Double Diffusive Salt Wedge)

  • 황진환
    • 한국해양환경ㆍ에너지학회지
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    • 제11권2호
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    • pp.92-97
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    • 2008
  • 일반적으로 해수가 강으로 침입하거나 담수가 해양으로 유입을 하면 두 유체간의 밀도차에 의한 밀도류의 성질을 가진다. 하지만, 염분과 온도가 동시에 밀도의 차를 결정하는 경우, 특히 이 중 하나가 중력과 불안정한 수직 분포를 갖게되면 이중확산이 혼합을 결정하는 중요한 요인이 된다. 본 연구에서는 고온, 고염의 수괴가 저온, 저염의 수괴로 진입할 때 기계적 혼합과 이중확산에 의한 대류가 혼합에 미치는 상대적 영향을 비교 연구하였다. 실험실에서 차갑고 염도가 없는 주 흐름에 온도가 높고 염분이 높은 밀도류를 조심스럽게 방류시켜 정상상태의 염수침입 형태를 유지하였다. 수평방향으로 따라 밀도율(Turner 1979)이 15정도 되면 온도와 염분의 유출입량비율이 가파르게 변화하였고, 전체적으로 방출구 부분에서 이중확산의 영향이 강하게 나타나게 되며 이 경우에는 총 방출량도 함께 증가하였다. 아울러 밀도율이 낮은 경우 밀도율이 높은 경우에 비해서 약 $6{\times}10$배의 높은 혼합율을 보였다.

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