• Title/Summary/Keyword: Intermittent Feeding

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Evaluation of Combined Vertical and Horizontal Flow Sand-Filled Reed Constructed Wetland with Intermittent Feeding for Sewage Treatment (간헐 주입 2단(수직 및 수평 흐름) 모래 갈대 인공습지에 의한 생활하수 처리)

  • Seo, Jeoung-Yoon
    • Journal of Wetlands Research
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    • v.16 no.2
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    • pp.261-268
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    • 2014
  • A sewage was treated using serially combined vertical(VFCW)and horizontal flow sand-filled reed constructed wetland(HFCW) with intermittent feeding. The sand had 1~3 mm diameter. The sewage entering the sewage treatment plant of Gyeonsang National University was fed into the reed constructed wetland bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^2{\cdot}day$ based on the surface ares of the VFCW. In the VFCW effluent pH values were lower than those of the influent, whereas they were higher than those of the influent in the HFCW. DO values were increased in VFCW, but they were decreased in the HFCW. The OTR was $58.72gO_2/m^2{\cdot}day$ in the VFCW and $7.72gO_2/m^2{\cdot}day$ in the HFCW. Average removal efficiencies were SS 94.80%, BOD 90.77%, $COD_{Cr}$ 85.87%, $COD_{Mn}$ 87.72%, T-N 64.74%, $NH_4{^+}$-N 86.44%, T-P 87.70%. Nearly, half of T-N in the effluent was $NO_3{^-}$-N but the concentration of $NO_2{^-}$-N in the effluent was less than 0.64 mg/L.

Experimental Study on the Effect of Temporary Clipping on the Histological Changes of the Arterial Walls of Rats

  • Koh, Hyeon-Song;Kwon, O-Yu
    • Biomedical Science Letters
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    • v.13 no.2
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    • pp.111-117
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    • 2007
  • Temporary occlusion of the parent artery or feeding artery is an useful method in microsurgery for cerebrovascular diseases. The advantages of the temporary clipping for intracranial aneurysm surgery have already been proven by many experimental and clinical reports. Currently, there are two methods of temporary clipping: 1) intermittent clipping, 2) continuous clipping. In many previous studies, the intermittent, repeated clipping technique was reported to reduce ischemic damage to the brain, but it is still debated. On the other hand, a comparison of the histological changes on the arterial wall between each clipping method has not been sufficiently reported yet. So the authors performed experimental temporary clipping on the common carotid and femoral arteries of about 25 rats using the Sugita temporary mini-clip. The specimens were divided into two major groups and seven subgroups: Group I (I-1, I-2, I-3, I-4, intermittent clippings for 5 minutes were done once, twice, three times, and few times), and Group C (C-10, C-15, C-20, continuous clippings for 10, 15, 20 minutes, respectively). The reperfusion time after the temporary clipping was the same as the clipping duration. Under light microscope, the histological findings by Hematoxylin-Eosin staining were examined in all specimens, which were obtained at each time interval after temporary clipping. Then the histological changes of the arterial walls by two different methods were compared with the normal specimen. The results suggest that intermittent temporary clipping is less damaging on the arterial wall than single continuous clipping.

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Red Pigment Overproduction by Fed-Batch Culture of Monascus anka (Monascus anka로부터 유기배양에 의한 적색소의 대량생산)

  • 김희구;박근태;손홍주
    • The Korean Journal of Food And Nutrition
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    • v.11 no.6
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    • pp.617-621
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    • 1998
  • The production of red pigment from glucose by fed-batch culture of Monascus anka was investigated. In batch culture using fermentor, 200 rpm of agitation speed, 1vvm of aeration volume, and 10% (v/v) of inoculum size were optimal, respectively. The red pigment production was increased by removal of wall-attached mycelium. In an intermittent feeding fed-batch culture, dry cell weight increased to 30 g/l, adn the red pigment content reached 350 of absorbance at 495nm. In a continuous feeding fed-batch culture, dry cell weight increased to 22g/l, and the red pigment content reached 190 of absorbance at 495nm.

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Feeding Ecology of Black Rockfish, Sebastes inermis (볼락, Sebastes inermis 의 섭식상태)

  • KIM Chong-Kwan;KANG Yong-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.5
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    • pp.637-641
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    • 1999
  • This study was carried out to understand feeding ecology of black rockfish, Sebastes inermis in the coastal waters off Shinsudo, Sachon. The specimens were collected by angling, gill net, small danish seine, and long-bag net from February 1984 to May 1985. The fish consisted of 5 age groups from 0 to 4. Feeding activity was more intensive in the early morning and late afternoon in spring and summer, but the fish showed intermittent feeding activities in autumn and winter. Although the food items of the fish changed slightly by seasons and with growth of the fish, main food items were cope pods, gammarids, caprellids, carideans, polychaetes, and brachyurans. Of these food items, cope pods were major preys for the fish of age group 0, and gammarids over age group 1. Evenness and diversity of the food items increased as the fish grew. In consideration of feeding organs, digestive organs and stomach contents of the fish, S. inermis seemed to be not only carnivore but also visual feeder consuming mainly small crustaceans.

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High Concentrated Spore Production of Bacillus thuringliensis by Fed-Batch Processes (유가식 배양공정에 의한 Bacillus thurngiensis의 고농도 포자생산)

  • 박창열;유연우
    • KSBB Journal
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    • v.15 no.3
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    • pp.219-225
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    • 2000
  • Both the production of high spore concentration and high insecticidal activity are required in the production of Bacillus thuringiensis to be used for the bacterial insecticide. In the production of high cell and spore concentrations of B. thuringiensis the continuous fed-batch culture(CFBC) and intermittent fed-batch culture(IFBC) were investigated at $28^{\circ}C$ by maintaining 40% dissolved oxygen concentration. When the final glucose concentration was 50 g/L the maximum viable cell number obtained using the CFBC with linear gradient feeding was $9.37{\times}109$ cells/mL and maximum spore concentration was $8.33{\times}109$ spores/mL which was approximately 84.4% yield of spore formation. When the final glucose concentration was 100 g/L the aximum viable cell and spore concentrations obtained using the IFBC with pH-statb were $1.38{\times}$1010 cells/mL and $1.35{\times}1010$ spores/mL respectively and the yield of spore formation was approximately 97.8%.

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Intermittent Strip Stock Advancing Accuracy Analysis of a Prototype Pneumatic Cylinder Driven Roll Feeder (공압실린더를 활용한 롤 피더의 간헐적 스트립 스톡 진행 정밀도 분석)

  • So, Jung-Duck;Kwon, Soon-Hong
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.19 no.3
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    • pp.353-358
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    • 2010
  • This research introduces a new and improved design for a pneumatic cylinder driven roll feeder wherein each of the principal rotating feeder parts is configured so as to have feeding accuracy and to be low manufacturing cost. The feed pitch accuracy of the proposed roll feeder was evaluated by measuring lengths of cut offs of the strip stock with a shear attached to an air press. The air press was designed, manufactured, and mounted on the same table of the proposed roll feeder such that the strip stock maintained horizontal plane until the strip stock entered into the shear. The proposed roll feeder and the air press were designed to be operated automatically by a PLC employed controller. The feed pitch accuracy of the proposed roll feeder was analyzed by setting the pitch as 10, 12.5, and 15mm. At each predetermined feed pitch, the proposed roll feeder was tested 300 times as one test set and replicated three times. The average lengths of the cut offs of the strip stock ranged from 9.98 to 10.13mm, from 12.42 to 12.57mm, and from 14.96 to 15.06mm at the predetermined 10, 12.5, and 15mm feed pitch, respectively, among the total of 900 samples of each feed pitch. Main cause of variation of the length of the cut off of the strip stock fed by the proposed roll feeder was considered to be fluctuation of the air press during recompressing period of the air compressor to pressurize the air in the air tank. The largest difference between the maximum and the minimum length of the cut off was appeared while the air compressor recompressing the air. The air compressor used for this study restricted the air delivered to the proposed roll feeder while it was still running. Thus, this air delivery restriction problem should be improved by stabilizing the air press while the proposed roll feeder is running.

Horizontal Flow Zeolite-Filled Reed Bed with Intermittent Feeding for Sewage Treatment (수평 흐름 제올라이트 갈대 여과상에 의한 생활하수 처리)

  • Seo Jeoung-Yoon;Kim Ean-Ho
    • KSBB Journal
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    • v.21 no.1 s.96
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    • pp.28-33
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    • 2006
  • A sewage was treated using a horizontal flow zeolite-filled reed bed. The sewage from the student dormitory of Changwon National University was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^2$ day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolite : $0.5{\sim}1mm$ and $1{\sim}3mm$ in diameter. Annual average removal efficiency was SS $88.5%,\;COD_{cr},\;86.1%,\;COD_{Mn}\;81.0%,\;T-N\;48.6%,\;NH_4^+-N\;97.1%$ and T-P 42.8%. T-N of effluent was mostly $NO_3^--N$ and the concentration of $NO_2^--N$ in effluent was lower than 0.1 mg/L. All removal efficiencies did not show a remarkable seasonal change.

Clinical Review about Dysphagia associated with Acute Ischemic Stroke (급성 허혈성 뇌졸중에 수반된 연하장애에 관한 임상적 고찰)

  • 한명아;김동웅
    • The Journal of Korean Medicine
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    • v.22 no.3
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    • pp.42-50
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    • 2001
  • Objectives : Dysphagia is common and severe problems of acute stroke determining the prognosis of stroke only second to mental change, and results in secondary fatal complications such as aspiration pneumonia, malnutrition, dehydration, etc. Therefore, we were to investigate the clinical characteristics of dysphagia accompanied by acute ischemic stroke. Methods : We selected subjects through clinical notes retrospectively, whose main problems included dysphagia resulted from acute stroke within 72 hours from onset who were admitted to the Internal Medicine Department of Wonkwang Oriental Medicine Hospital from Jan. 2000 to Apr. 2001. We assessed the severity of dysphagia from admission to discharge using a staging method : stage 0 is normal without dysphagia, stage 1 is nearly normal except for intermittent dysphagia, stage 2 is compensated abnormal swallowing requiring adjusted diets or delayed feeding time, stage 3 is uncompensated abnormal swallowing resulted in weight loss down to 10% of initial and daily aspiration, coughing, and vomiting, stage 4 is uncompensated abnormal swallowing resulting in weight loss beyond 10% and recommended for non-oral feeding, and stage 5 is 100% non-oral feeding by L-tube, or gastrostomy or NPO state. Results : Dysphagia was improved statistically significantly from the mean stage of $3.6{\pm}0.29$ on admission to $1.88{\pm}0.32$ on discharge (P<0.05). On average $7.1{\pm}1.48$ days were required for improving more than one stage level. As patients were older and the stage of dysphagia was worse on admission, severity of dysphagia was more difficult to improve (correlation coefficiency was 0.55 and 0.77 respectively, P<0.05). Aspiration pneumonia was complicated in 13 patients of the total 25 at mean dysphagia stage of $3.36{\pm}0.37$. However, any specific values such as lesion size, lesion site, sex, age, past history and NIH Stroke Scale on admission did not affect it (P>0.05). Conclusion : Clinical course of dysphagia was determined about I week from the onset. Aspiration pneumonia was mainly complicated during oral feeding periods. If there were no improvement of dysphagia over 2-3 weeks, then non-oral feeding such as Levin tube or gastrostomy must be considered.

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Characteristics of Macroinvertebrates Food Webs affected by Dry Channel in an Intermittent Stream System of the Echi River in Japan

  • Shin, Hyun-Seon;Nozomi, Amahashi;Na, Young-Eun;Park, Hong-Hyun;Cho, Kwang-Jin;Seo, Ye-Ji;Osamu, Mitamura
    • Journal of Climate Change Research
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    • v.6 no.3
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    • pp.167-173
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    • 2015
  • The purpose of study is to identify trophic pathways from organic matter to macroinvertebrates in terms of the consumer and to characterize the food webs in an intermittent stream system of the Echi River in Japan. The ${\delta}^{13}C$ values of macroinvertebrates and their potential food sources indicated the scraper (Psephenoides spp., Ecdyonurus levis) and collector-gatherer (Ephemera strigata, Paraleptonphlebia chocolata) feed on periphyton and POM (particulate organic matter) in situ. Davidius lunatus, and Hexatoma spp., which were identified as predators, may feed upon Ephemera strigata and Stenelmis larvae, respectively. At station characterized by seepage water, the ${\delta}^{15}N$ values of Ecdyonurus levis, Lymnaea auricularia, and Rhyacophila nigrocephala larva probably showed relatively lower values according to its diets. Even in homogenous species, the trophic pathways of macroinvertebrates in situ exhibited considerable variation; this reflected the trophic pathways from organic matter to the consumer depending on habitat characteristics in stream.

Fed-Batch Culture for Polyhydroxyalkanoate Overproduction by Pseudomonas sp. HJ (Pseudomonas sp. HJ로부터 Polyhydroxyalkanoate 대량생산을 위한 유가식 배양)

  • 손홍주;이상준
    • KSBB Journal
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    • v.11 no.2
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    • pp.201-210
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    • 1996
  • The production of polyhydroxyalkanoate(PHA) from glucose by batch and fed-batch culture of Pseudomonas sp. HJ was studied. In batch culture using fermentor, 400 rpm of agitalion speed, 2 vvm of aeration rate, 18 hours of inoculum age, and 5% (vlv) of inoculum size were optimal. PHA production was not increased by deficiency of oxygen. In a batch culture, the final call mass was $6.251g/\ell$, and PHA content was 20% of dry cell weight. In a constant feeding fed-batch culture, cell mass increased to $33.24g/\ell$, and PHA content reached 48.9% of dry cell weight. In an intermittent feeding fed-batch culture, cell mass increased to $37.89g/\ell$, and PHA content reached 53.5% of dty cell weight.

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