• Title/Summary/Keyword: Water mass changes

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Characteristics of Metal Pollutants and Dynamic EMCs in a Parking Lot and a Bridge during Storms (주차장 및 교량 강우유출수의 중금속 오염물질 특성과 동적 EMCs)

  • Kim, Lee-Hyung;Lee, Seonha
    • Journal of Korean Society on Water Environment
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    • v.21 no.4
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    • pp.385-392
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    • 2005
  • The control of nonpoint source pollution is essentially needed to successfully perform the Total Maximum Daily Load program. Of the various land uses in the nonpoint source, the paved areas such as a parking lot and a bridge are stormwater intensive land uses because of high imperviousness and high pollutant mass emissions. This research was performed to understand the magnitude and nature of the stormwater emissions with the purposes of quantifying stormwater pollutant concentrations and mass emission rates from a parking lot and a bridge. Two monitoring sites in Kongju city were equipped with an automatic rainfall gages and an automatic flow meter for accumulating the data such as rainfall, water quality and runoff flow rates. This paper will summarize the metal concentration changes during the storm duration and metal EMCs to characterize the concentration profiles in a parking lot and a bridge. Also a new concept, dynamic EMC, will be proposed to find the relationship between EMC and first flush effect. It can be used to determine the economical treatment criteria in best management practices.

A Study on Change of Sea Water Quality due to the Development Plan of Ilgwang Harbour (일광항의 항만개발에 따른 수질변화에 관한 연구)

  • 이중우;국승기
    • Journal of Korean Port Research
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    • v.12 no.2
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    • pp.303-312
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    • 1998
  • It is necessary to quantitatively asses the influence of tidal currents to analysis the coastal current patterns before or after constructing offshore structures like as breakwaters. This assesment can be made through the use of simulation models designed to reproduce the water movements of the area. And it is very important to predict a phenomenon of pollutant dispersion in the area. In this study, in order to predict the changes of sea water quality for the port development plan, Ilgwang harbour, located at the east coast of Pusan, the numerical computations were carried out. The flow patterns were investigated before and after the development of the harbour bay and coastal area connected on it. The computational models are an extension of earlier work on the flow which used the ADI Method (Alternating Direction Implicit Method) in appling to Osaka Bay by KANEKO et al. The transport of pollutant constituents depends upon the currental characteristics of the water-transporting medium. In the currental flow model, water velocities and water levels are computed throughout the regions of it. These value are then used in the mass-balance equation to obtain the pollutant-constituent transport. As a result of this research, the present water quality of Ilgwang harbour and the coastal areas connected on it was proved out some good condition. The changes of sea water quality due to the port development plan of the Ilgwang habour bay and the coastal area were not large compared with the present condition, but it will be likely able to get worse by increasing the semi-enclosed areas in the harbour bay. In order to improve the water quality of the area after development, the method to activate tidal exchange in the area can be needed, as a mitigation technique.

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Impact of BS replacement mortar's application to ERCO on moisture evaporation and contraction changes (BS 치환 모르타르의 ERCO 도포시 수분증발 및 수축변화에 미치는 영향)

  • Baek, Cheol;Lee, Jae-Hyeon;Hwang, Chan-Woo;Jang, Deok-Bae;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.10a
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    • pp.115-116
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    • 2016
  • This study applied BS replacement mortar's ERCO to see what impact it has on moisture evaporation and contraction changes, and resulted in the following. Depending on the rate of change in length according to the cure method of BS replacement mortar, high-strength areas were shown to have a bigger increase in the rate of change in length than regular or low-strength areas, and differences in rate of change in length due to ERCO cure methods were shown to be slight. For rate of changes in mass, on the whole there was an increase in the order of dry curing, cover curing, 7-day water curing, and28-day water curing. A comprehensive view says that after removal of test piece specimens, ERCO application did not expect a sufficient curing effect in the BS area.

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Changes in the Macrobenthic Community in Sihwa Tidal Flat After Operation of the Tidal Power Plant (조력발전소 가동 후 시화갯벌의 대형저서동물군집 변화)

  • Kim, Minkyu;Koo, Bon Joo
    • Ocean and Polar Research
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    • v.38 no.4
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    • pp.315-324
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    • 2016
  • In this study, we investigated changes in the macrobenthic community in Sihwa tidal flat before and after the operation of a Tidal Power Plant (TPP). In order to investigate changes in the macrobenthic community structure, field surveys were conducted at eighteen stations in 4 transect lines every September from 2011 to 2015. Mean density of macrobenthos decreased to $116ind./m^2$ in 2015 from $1,602ind./m^2$ in 2011. While the mean density of macrobenthos has decreased, species richness and biomass have gradually increased. The species diversity and SEP (Shannon-wiener Evenness Proportion) have also gradually increased over time since the operation of the TPP. The macrobenthic community in Sihwa tidal flat was divided into 4 groups on a yearly base. Before the operation of TPP, opportunistic species such as Neanthes succina and Polydora cornuta largely contributed to the structure of the macrobenthic community, while equilibrium species such as Periserrula leucophryna and Scopimera globosa contributed after the operation. With the operation of TPP, the macrobenthic community has rapidly recovered and this might be related to improvement in the quality of water and sedimentary environments as a result of an increase in water mass volume exchanged through the TPP gate.

Thermodynamic properties and structural geometry of KMgCl3·6H2O single crystals

  • Yoon, Hyo In;Lim, Ae Ran
    • Journal of the Korean Magnetic Resonance Society
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    • v.19 no.3
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    • pp.119-123
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    • 2015
  • The thermodynamic properties and structural geometry of $KMgCl_3{\cdot}6H_2O$ were investigated using thermogravimetric analysis, differential scanning calorimetry, and nuclear magnetic resonance. The initial mass loss occurs around 351 K ($=T_d$), which is interpreted as the onset of partial thermal decomposition. Phase transition temperatures were found at 435 K ($=T_{C1}$) and 481 K ($=T_{C2}$). The temperature dependences of the spin-lattice relaxation time $T_1$ for the $^1H$ nucleus changes abruptly near $T_{C1}$. These changes are associated with changes in the geometry of the arrangement of octahedral water molecules.

NMR-based monitoring of the hangover curing effects of deep sea water minerals

  • Ha, Jong-Myung;Woo, Young Min;Kim, Andre
    • Journal of the Korean Magnetic Resonance Society
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    • v.22 no.4
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    • pp.82-90
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    • 2018
  • The term "hangover" refers to symptoms such as headache, heartburn, nausea, and dizziness caused by acetaldehyde created through alcohol decomposition in the body after alcohol intake. Many scientists have conducted research on diverse drugs, foods, and medicinal herbs aimed at eliminating hangovers. However, research on metabolism to objectively verify or measure their effects on hangover symptoms has been lacking. Accordingly, in this study, deep sea water minerals were administered orally at varying concentrations to rats that consumed alcohol, and changes in the levels of amino acids in their bodies were measured using nuclear magnetic resonance spectroscopy to gauge the minerals' effects on hangover symptoms. Thus far, biochemical research on hangover cures has been confined to basic research measuring changes in the levels of alcohol dehydrogenase and acetaldehyde dehydrogenase as well as in the concentrations of ethanol, acetaldehyde, and acetate using spectroscopes such as enzyme-linked immunosorbent assay kits or gas chromatography-mass spectrometers. In comparison, this study presents pharmacokinetic research that simultaneously tracked biomaterials including amino acids and organic acids, metabolites associated with hangover, to clarify hangover mechanisms more specifically. In addition, this study examined hangover mechanisms without an external supply of tracked materials not overlapping with alcohol metabolism-related materials, such as external amino acids and sugars.

A Study on Durability Variation of Concrete due to Water Content Changes (콘크리트 내 수량증감에 의한 내구 품질 변동에 관한 연구)

  • Woo, Young-Je;Ryu, Hwa-Sung;Jung, Sang-Hwa;Kwon, Ki-Jun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.2 s.25
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    • pp.1-6
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    • 2007
  • When the water content within concrete swells, diverse problems occur such as drop in durability. Due to this reason, a change is being managed in the unit water contents by using electric capacity measurements, high frequency heating methods, and unit-volume mass measurements, which are methods of measuring the unit water contents. Particularly, Japan is prescribing the guideline of management on a change in unit water content unit quantity $({\pm}10,\;15,\;20kg//m^3,\;etc.)$. However, the guideline of Japan dose not consider a fall in durability, and is decided on the value of pass-fail criteria by random fabrication errors and measurement errors. Consequently, this study was aimed to investigate the influence of a change In water content within concrete due to an addend caused by management error and to an artificial addend, upon drop in durability.

Using Quality of Life Scales with Nutritional Relevance after Gastrectomy: a Challenge for Providing Personalized Treatment

  • Lee, Seung Soo;Yu, Wansik;Chung, Ho Young;Kwon, Oh Kyoung;Lee, Won Kee
    • Journal of Gastric Cancer
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    • v.17 no.4
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    • pp.342-353
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    • 2017
  • Purpose: This study evaluated the changes in nutritional status based on quality of life (QoL) item-level analysis to determine whether individual QoL responses might facilitate personal clinical impact. Materials and Methods: This study retrospectively evaluated QoL data obtained by the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) and Quality of Life Questionnaire-Stomach (QLQ-STO22) as well as metabolic-nutritional data obtained by bioelectrical impedance analysis and blood tests. Patients were assessed preoperatively and at the 5-year follow-up. QoL was analyzed at the level of the constituent items. The patients were categorized into vulnerable and non-vulnerable QoL groups for each scale based on their responses to the QoL items and changes in the metabolic-nutritional indices were compared. Results: Multiple shortcomings in the metabolic-nutritional indices were observed in the vulnerable groups for nausea/vomiting (waist-hip ratio, degree of obesity), dyspnea (hemoglobin, iron), constipation (body fat mass, percent body fat), dysphagia (body fat mass, percent body fat), reflux (body weight, hemoglobin), dry mouth (percent body fat, waist-hip ratio), and taste (body weight, total body water, soft lean mass, body fat mass). The shortcomings in a single index were observed in the vulnerable groups for emotional functioning and pain (EORTC QLQ-C30) and for eating restrictions (EORTC QLQ-STO22). Conclusions: Long-term postoperative QoL deterioration in emotional functioning, nausea/vomiting, pain, dyspnea, constipation, dysphagia, reflux, eating restrictions, dry mouth, and taste were associated with nutritional shortcomings. QoL item-level analysis, instead of scale-level analysis, may help to facilitate personalized treatment for individual QoL respondents.

Ovarian Remnant Syndrome in a 5-Year-old Pekingese Bitch (5년령 패키니즈 암컷의 난소잔존증후군 1예)

  • eum Kyoung-Hwan;Kang Hyun-Gu;Kim Ill-Hwa;Lee Jong Hwan;Lee Kee-Chang;Lee Chung-San;Lee Dong-Yub
    • Journal of Veterinary Clinics
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    • v.22 no.4
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    • pp.424-427
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    • 2005
  • A 5-year-old Pekingese bitch was presented with a history of vaginal bleeding and copulation before 4-week. Ovarian remnant syndrome was diagnosed on the clinical changes, vaginal cytology and exploratory laparotomy. An abdominal mass was diagnosed on radiography, ultrasonography and Computed Tomography. The remnant of ovarian tissue and an abdominal mass were removed surgically under general anesthesia. Ultrasonographic examination of the removed ovarian tissue (water bath scanning) revealed three corpora lutea. The condition resolved following surgical excision of the remaining ovarian tissue and an abdominal purulent mass.

Heat and Mass Transfer in Hygroscopic Rotor During Adsorption and Desorption Process (흡착과 탈착 과정 동안 제습 로터의 열/물질 전달)

  • Shin, Hyun-Geun;Park, Il Seouk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.11
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    • pp.977-984
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    • 2013
  • A hygroscopic rotor comprises many microchannels with high adsorption characteristics. In this study, the iterative adsorption/desorption processes that were affected by the humid air flow in a channel were numerically simulated. In consideration of the accuracy and computational costs, in the desiccant layer, only surface diffusion was considered in this simulation. The results were compared with the previous numerical results and found to show good agreement. By conjugating the heat and mass transfer between the desiccant and the flow layers, temporal and spatial changes in the vapor mass fraction, adsorbed liquid water mass fraction, and temperature in the channel were presented.