• Title/Summary/Keyword: Flushing period

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The Effect of Rainfall on the Water Quality of a Small Reservoir (Lake Wangkung, Korea)

  • Hwang, Gil-Son;Kim, Jae-Ok;Kim, Jai-Ku;Kim, Young-Chul;Kim, Bom-Chul
    • Korean Journal of Ecology and Environment
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    • v.38 no.spc
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    • pp.39-43
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    • 2005
  • The dynamics of water quality with the storm events were analyzed in a small reservoir for irrigation, Lake Wangkung. Water quality of the inflowing stream fluctuated seasonally with the variation of flow rate. Thermal stratification was consistent from April to October below 2 m depths and anoxic layer was developed below 2 m depth in summer. The unique feature of temperature showed that thermal stratification was disrupted by a heavy rain event during monsoon, but hypolimnetic hypoxia were reestablished after a few days. Phosphorus and nitrogen increased immediately following storm events. The marked increase may be due to the input of P-rich storm runoff from the watershed. Internal phosphorus loading can be one of the explanations for TP increases in summer. When there was a storm, total populations of phytoplankton and zooplankton was reduced immediately following the storm, indicating possible flushing of algae and zooplankton. After a lag period of low-density the plankton population bloomed to a peak again within five days after the storm. Turbid water in lake became clear again which coincided with the time of the phytoplankton buildup. The results demonstrate that water quality is regulated greatly by rainfall intensity in Lake Wangkung.

A Demonstrative Operation of A Membrane Filtration System in Siheung Water Treatment Plant (시흥정수장 막여과시설 시범운영)

  • 김한승;김충환;김학철;윤재경;안효원
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.07a
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    • pp.57-68
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    • 2004
  • A demonstrative operation of a membrane system with its caparity of 3,600m$^3$/d was carried out using reservoir water as raw water for the application of membrane filtration system to drinking water treatment. The operation was undertaken at a constant flux of 0.9 m$^3$/m$^2$/d for three months. Backwashing with NaClO of 3 ppm was allowed for 30 seconds every 20 minutes of filtration. Physical cleaning was introduced after 69 times of filtration/backwashing cycle with air-scrubbing and backwashing for 1 minute, and flushing for 2 minutes. In this study, water treatment performance was investigated compared with the existing rapid sand filtration process. The membrane system was operated with no significant problems during the test period. Higher water quality was obtained in the membrane filtration than in the rapid sand filtration in terms of particulate matters such as turbidity and microbes. Although the finished water of the membrane filtration contained slightly higher concentration in dissolved matters than that of the conventional one, it met the drinking water standard. The demonstrative operation showed that membrane filtration has a reliability in drinking water treatment. Researches should be needed on cost analysis through long-term operation and optimization of operation condition for further application.

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Acne Treatment Cases with Hwangryeonhaedok-tang (황련해독탕가미방(黃連解毒湯加味方) 발효한약으로 치료한 여드름 환자 증례)

  • Oh, Chung-Sun;Kim, Mi-Sun;Kim, Il;Kim, Hye-Yoon;Park, Sung-Ik;Choi, Seung-Il;Hong, Dae-Sung
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.22 no.3
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    • pp.228-236
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    • 2009
  • Objectives : Acne, one of the most common disorders in dermatology clinic, is a chronic inflammatory disease which has the symptoms of comedones, papules, pustules, cysts, nodules and scars mainly on the face. Although some of pathologic findings are suggested, but the exact causes and mechanisms are not yet known in Western Medicine. Hwangryeonhaedok-Tang(HRHDT) is an antiinflammatory, antipyretic and detoxifying herb decoction. In this report, we would like to share our experience of acne treatment with HRHDT. Methods : We had treated several patients with acne, facial flushing and uprising febrile sensation on face using oral administration and external application of HRHDT. HRHDT is basically made up with Scutellariae Radix, Coptidis Rhizoma, Phellodendri Cortex and Gardeniae Fructus. In this trial, several other herbs were added according to the individual patient's accompanying symptoms. After the decoction of herbs in amount for 10 days, $Yogourmet^{(R)}$ Kefir Starter 10 g was added to the herbal solution that was then fermented in an incubator at $25^{\circ}C$ for 72 hours, and divided into 30 doses. Results : Photographies were taken before and after the treatment. The severities of acne were evaluated with these photos according to the Korean Acne Grading System(KAGS). As results, we observed dramatic clinical improvements and the decreases of KAGS grades after the average treatment period of 8 weeks. The medication was orally administered 3 times a day and the external treatment was applied average twice a week during the whole treatment period. Conclusions : From these results, HRHDT may be considered as a good prescription for the febrile and toxic type of acne patients.

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A case report of embryo transfer with air-transported fresh bovine embryo produced by multiple ovulation in Hanwoo

  • Sang-Yup Lee;Seong-Eun Heo;Won-Jae Lee
    • Journal of Animal Reproduction and Biotechnology
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    • v.38 no.2
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    • pp.84-88
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    • 2023
  • Because multiple ovulation embryo transfer (MOET) in cattle includes several benefits such as wide spreading of genetically superior offspring for long distance, this biotechnological method has been widely applied to Hanwoo. When the recipients are not stayed close after embryo recovery from donor, the embryos are moved to other farms via several vehicles (car, train, and airplane). However, air travel induces lesser oxygen level, increased vibration, lower air pressure, higher noise, and increased exposure of cosmic radiation to living things than ground level. It was still unknown that fresh embryos obtained from multiple ovulation of Hanwoo could maintain their fertility after being transported via air plane, the present case report introduced a clinical case of MOET in Hanwoo after shipping fresh embryos via air transportation. The donor was multi-ovulated via follicle-stimulating hormone series of injection, which was followed by a gonadotrophin-releasing hormone injection and artificial insemination twice. The embryos were recovered by the uterine flushing, packed in ministraws, transported to recipients for 6 h including 1 h air flight, and then transferred to the synchronized recipients. During pregnancy diagnosis of early gestation period, 5 of 7 recipients (71.4%) presented no heat signs and showed fetal sacs with fluid under transrectal ultrasonography. After normal gestation period, all recipients naturally delivered healthy calves (male n = 2 and female n = 3) without abortion, stillbirth, and premature birth. The present case report indicated that transportation of fresh embryos for MOET via domestic flight in Korea did not affect to their fertility.

Quality Changes of Retorted Samgyetang During Storage Depending on the Degassing Methods (탈기 포장 방법에 따른 레토르트 삼계탕의 저장 중 품질 변화)

  • Jang, Min Jun;Lee, Jin Ho;Lee, Keun Taik
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.19 no.2
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    • pp.67-73
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    • 2013
  • This study investigated the quality changes of Samgyetang during storage, resulting from various degassing methods used at the packaging stage. Three different samples were prepared, one without any treatment (CON), a second with reduced head space volume by squeezing the pouch (RHS), and a third by flushing with nitrogen gas (NGF). These were retorted at $120^{\circ}C$ for 65 min under the F-value of approx. 8.0, and stored at $25^{\circ}C$ for 9 months. The oxygen ratio in the head space and the dissolved oxygen content of NGF samples tended to be lower than those of other samples over the storage period. Compared to the CON, the acid values of NGF and RHS samples were lower than the CON from month 3 and 6 (p<0.05). During storage, volatile basic nitrogen values of NGF and RHS samples increased slowly compared to the CON. To delay quality deterioration and extend the shelf-life of Samgyetang products, the reduction of oxygen content in the head space of the retort pouch (preferably by flushing with nitrogen gas) is recommended, even though no significant differences in sensory evaluation were observed among the samples during 9 months of storage (p>0.05).

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Advanced Water Treatment of High Turbidity Source by Hybrid Process of Multi-channels Ceramic Microfiltration and Activated Carbon Adsorption (다채널 세라믹 정밀여과 및 활성탄 흡착 혼성공정에 의한 고탁도 원수의 고도정수처리)

  • Park, Jin-Yong;Lee, Hyuk-Chan
    • Membrane Journal
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    • v.18 no.4
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    • pp.325-335
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    • 2008
  • In this study, we used multi-channels ceramic membrane having larger permeate volume per unit time rather than tubular membrane. The hybrid process for advanced drinking water treatment was composed of granular activated carbons (GAC) packing between module inside and outside of multi-channels microfiltration membrane. Instead of natural organic matters (NOM) and fine inorganic particles in natural water source, modified solution was prepared with humic acid and kaolin. Kaolin concentration was fixed at 30mg/L and humic acid was changed as $2{\sim}10\;mg/L$ to inspect effect of organic matters. As a result, both resistance of membrane fouling ($R_f$) and permeate flux (J) were highly influenced by concentration of humic acid. Also, in result of water-back-flushing period (FT) effect, the shorter FT was the more effective to reduce membrane fouling and to enhance permeate flux because of frequent water-back-flushing. However, the optimal FT condition was 8 min when operating costs were considered. Then, the hybrid process using multi-channels ceramic membrane and GAC was applied to lake water treatment. As a result, average treatment efficiencies in our experiment using the hybrid process were 98.02% for turbidity, 75.64% for $UV_{254}$ absorbance, 7.18% for TDS and 84.73% for $COD_{Mn}$.

Efficacy of 1:1000 Diluted Heparin versus 0.9% Normal Saline for Maintenance of Intermittent Intravenous Locks (희석된 헤파린과 생리식염수가 간헐적 말초정맥장치의 폐색, 유지기간 및 정맥염 발생에 미치는 영향)

  • Park Mi-Mi;Kim Chang-Hee;Cho Eun-Suk;Lee Mi-Jung;Kim Hae-Suk
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.7 no.2
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    • pp.208-221
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    • 2000
  • The objective of this research was to compare the flushing effects using 1:1,000 diluted heparin or 0.9% normal saline in relation to needle gauge and frequency of IV medications. The comparative categories were clotting, duration of patency, and incidence of phlebitis. The design of research was a Nonequivalent Control group, Post test, Nonsynchrorized Design. The independent variable was 0.9% normal saline flushing the IV locks and the dependent variables were clotting, duration of patency, and incidence of phlebitis. Subjects were medical-surgical inpatients over 15 years old and with peripherally placed IVs who were hospitalized in a university medical center. Exclusion criteria included foreigners and those who were rejected for this research. The final sample for data analysis included 295 IV sites in 194 patients; 154 were in the saline group and 141 were in the heparin group. Subjects were assigned to have IV locks is flushed with 0.9% normal saline in the experimental group and to have IV lock flushed with 1:1,000 diluted heparin(100 units) in the control group. In order to increase reliability, the nurses who were assigned to the units involved in the study received an explanation on the standard method for locking an IV, recording method for observational data and criteria for the detection of phlebitis. Data were collected for a period of 2 weeks, from March 16, 2000 to March 29, 2000. Total duration of IV was defined the time of IV insertion to the time of discontinuation. Phlebitis was defined as the presence of the following : pain, swelling. erythema at the insertion site. Chi-square was used to determine the association between the degree of clotting, duration of patency, and incidence of phlebitis for the diluted heparin or the normal saline and needle gauge and frequency of IV medications. The results are summarized as follows : (a) There was difference in the degree of clotting between two groups($X^2=5.882$, p=.015). (b) There was no difference in the degree of duration of patency between two groups($X^2=2.439$, p=.295). (c) There was no difference in the incidence of phlebitis between two groups($X^2=0.190$, p=.663). (d) There was difference in the degree of clotting($X^2=6.209$, p=.013) and in the degree of duration of patency($X^2=6.978$, p=.031) according the needle guage between the two groups. (e) There was difference in the incidence of phlebitis($X^2=5.008$, p=.025) according to the frequencies of IV injection between two groups.

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Development of Wastewater Treatment and Recycle Technology Using a Tubular Ceramic Ultrafiltration Membrane 1, Effect of Periodic Backflushing (관형 세라믹 한외여과막을 사용한 폐수처리 및 재활용기술개발 : 1, 주기적 역세척 효과)

  • 박진용
    • Membrane Journal
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    • v.9 no.3
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    • pp.178-184
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    • 1999
  • A periodic backflushing was performed to reduce the membrane fouling of ultrafiltration for wastewater, and the effect and the optimum condition were investigated in this study. The alumina¬ceramic tubular membrane with pore size of 0.02${\mu}m$ was used for the wastewater treated by coagulation and sedimentation from two paper plants, of which A plant made toilet paper by recycling milk paper cartons and B plant recycled corrugated cardboards. And the effect of periodic backflushing to membrane fouling and quality of permeate were studied with a constant backflushing time of 3 sec. As results of measuring SS, TDS, and COD of source and permeate, the rejection rate of SS showed the highest value at the backflushing period of 15 see, which was the shortest time in these experiments, in case of waste¬water discharged from A plant. However, the rejection rate of COD had the highest value at the period of 30 sec for wastewater from both A and B plant. Then, the rejection rate of TDS was almost same at 30 and 60 sec for A plant wastewater, and the highest at 60 see for B plant. The effect of periodic back¬flushing to membrane fouling was investigated by change of permeate flux according to operating time. The permeate flux decreased slowly at the operation with backflushing, and was higher compared with that without backflushing in both case of A and B wastewater. But, the optimum period with the highest flux of A wastewater was different from that of B, because SS and COD of A was higher than those of Band TDS of B was higher than that of A.

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Analysis of First Flushing Effects for the Vineyard Storm Runoff (강우시 포도밭에 대한 초기세척효과 분석)

  • Yoon, Young-Sam;Kwon, Hun-Gak;Lee, Jae-Woon;Yu, Jay-Jung;Lee, Jae-Kwan
    • Journal of Environmental Science International
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    • v.20 no.8
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    • pp.977-986
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    • 2011
  • This study analyzed the characteristics of stormwater runoff in the orchard areas and quantitatively estimated effluence of nonpoint source pollutants for the volume of runoff. Two target areas under vine cultivation were each $2,000m^2$ and $1,800m^2$, located in Gyeongju City. Since grape was the only crop on the target area, the characteristics of stormwater runoff at vineyard could be evaluated independently. A total of 51 rainfall events in the vineyard area during two years(2008-2009) was surveyed, and 19 of them became stormwater runoff, with rainfall ranging 16.5 - 79.7 mm and antecedent dry period of 1-13 days. The pollutant runoff loads by volume of stormwater runoff showed BOD ranging 19.5 - 45.3% in 30% of runoff volume. The average pollution discharge rate was 32.4%, indicating small first flush effect of BOD. The range of SS concentrations was 5 - 52.0% in 10% of runoff volume, showing the average 28.7% of discharge rate, about 3 times more than rainfall effluent. TOC and TN appeared to be similar to the results of BOD, the average discharge rate of 30.9% and 30.6% for TOC and TN, respectively, for 30% of stormwater runoff volume. Average discharge rate of COD and TP in the same runoff volume was 35.1% and 36%, respectively, showing comparatively high discharge ratio. As the targeted vineyard area was permeable land, the pollution load ratio against rainfall-runoff volume appeared to be 1:1, implying no strong first flush effect for all the survey items.

EFFECT OF WINTER SUPPLEMENTATION ON THE PERFORMANCE OF BALOCHI EWES GRAZING NATIVE RANGELANDS IN HIGHLAND BALOCHISTAN

  • Rafique, S.;Munir, M.;Sultani, M.I.;Rehman, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.4
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    • pp.333-339
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    • 1991
  • Eighty-two ewes of Balochi breed, two to four years of age were used in a completely randomized design to study the effect of winter supplementation on their performance in Kalat area of Balochistan and randomly divided into two groups of 40 and 42 animals. Two treatments (T1 and T2) studied were : 250 gm/animal/day of a 50 : 50 mixture of cottonseed cake and barley grain fed from Oct. 20 to Dec. 18, 1988 plus grazing and 500 gm/animal/day of the same feed mixture fed from Oct. 9 to Dec. 18, 1988 in addition to grazing. Lucerne hay and wheat straw in a 50 : 50 ratio were provided to all the ewes for a period of one month from Jan. 6, 1989 @ 320 gm/animal/day to sustain them in severe winter. Same feeding levels to the same ewe groups were again fed from Mar. 1 to May 27, 1989. Three breeding rams stayed with the flock from Nov. 1 to Dec. 13, 1988. Lambing took place from Apr. 2 to May 12, 1989. Conception, lambing and mortality percentage was found different (P<.05) between T1 and T2 (12.5 vs 14.8 kg). The ewes on T2 maintained higher body weights throughout winter than the ewes on T1. The results are suggestive of improvement in conception rate with winter supplementation (flushing) and decrease in ewe mortality. Late-gestation and early-lactation supplemental feeding of ewes results in increases in weaning weights of their lambs.