• Title/Summary/Keyword: Floatation

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Theoretical Analysis of Wave Energy Converter

  • Oh, Jin-Seok;Komatsu, Toshimitsu;Kim, Yun-Hyung
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.1
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    • pp.169-174
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    • 2008
  • Floating devices, such as a cavity resonance device take advantage of both the water motion and the wave induced motions of the floating body itself. The wave energy converter is known commercially as the WAGB(Wave Activated Generator Buoy) and is used in some commercially available buoys to power navigation aids such as lights and horns. This wave energy converter consists of a circular floatation body which contains a vertical center pipe that has free communication with the sea. A theoretical analysis of this power generated by a pneumatic type wave energy converter is performed and the results obtained from the analysis are used for a real wave energy converter for buoy. This paper presents the analysis results and the design method for the WEC(Wave Energy Converter), and the associate results are application to the commercially available WEC for buoy. Maximum performance of WEC occurs at resonance with driving waves. The analysis of WEC is performed with LabVIEW program, and the design method of WEC for buoy is suggested in this paper.

Epizootiologic Surveys on Canine Parvovirus Infections of Dogs Kyungbuk West Area (경북서부지역에서의 개 파보바이러스 감염상황 조사)

  • 김성국;이정아;오강희;박영구
    • Korean Journal of Veterinary Service
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    • v.17 no.3
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    • pp.174-180
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    • 1994
  • The disease syndrome characterized by the acute vomiting and diarrhea with high mortality had been greatly epidemic in Kyungbuk West Area since March 1990 and it was followed serologically for the classification of the agent. The agent present in feces of dogs associated with this syndrome had characteristic feature in agglutinating pig red blood cells that was specifically inhibited by anti-CPV reference dog serum. This also showed the serological identity with the reference CPV antigen in Hemagglutinating inhibition test. The result obtained were summarized as follows : 1. During 5 years(March. 1990∼September. 1994), 1,470 dogs were investigated on the actual condition of CPV infections. The Infection rate of CPV from dogs was 62.5% and mortality rate was 59.8%. 2. Among 24 fecal samples collected from the dogs with enteric disease, all showed the hemagglutinating activity to porcine erythrocyte ranging from 40 to 5,120 of HA titers. 3. Among 12 sera samples collected from the dogs with enteric disease, all showed the serological identity with the reference CPV antigen from 5 to 5,120 of HI titers. 4. Bacteriologic examination of fecal specimens resulted in the isolation of pathogeric bacteria such as Staphylococcus sp, Streptococcus sp, Escherichia coli and Bacillus. Cultures for salmonella sp and Clostridium remaind negative. 5. The prevalence and identification of internal parasites were determined by fecal examination using the floatation methods. From 20 fecal samples 12(60.0%) were isolated and their species were Toxacara canis, Toxascaris leonina, and coccidium.

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A Survey on the Prevalence of Internal Parasites in Korean Native Goats and Sheep of Chonbuk Area (전북지방 산양과 명양의 내부기생충 실태조사)

  • 양홍지;서창섭;정재명;김종승
    • Korean Journal of Veterinary Service
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    • v.17 no.3
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    • pp.190-197
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    • 1994
  • In order to monitor the parasites, 303 fecal samples were taken from Korean native goats (n=279) and sheep(n=24) in Chonbuk area. The identification of the parasites were determimed by the fecal examination using the floatation or sedimentation methods and microscopical examination, respectively. The obtained results were summarized as follows ; 1. The detection rate of the parasites from Korean native goats and sheep was 98.2% and 83.3%, respectively. 2. In Korean native goat, mixed infection rate was single 7.5%(21 heads), double 47.3%(132 heads), triple 40.8%(114 heads), quadraple 5.0%(14 heads) and quintuple 2.5%(7 heads). 3. In sheep, mixed infection rate was single 12.5%(3 heads), double 45.8%(13 heads) and triple 16.6%(4 heads). 4. The parasites isolated were identified as Eimeria spp. from 283 heads, Oesophagostomum spp. from 96 heads, Ostertagia spp. from 97 heads, Strongylodes papillus from 97 heads, Heamonchs spp. from 73 heads, Trichostrongylus spp. from 42 heads, Moniezia expenza from 26 heads, Cooperia spp. from 16 heads, Nematodirus spp. from 9 heads, Bonostomum spp. from 9 heads, Paraphistomum spp. from 7 heads, and Fasciola hepatica and Capillaria spp. In 2 heads, in order.

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Prevalence of parasite infection of chickens in Jeonbuk province (전북지방 닭의 내부기생충 감염상황)

  • Choi Eun-Young;Jang Sae-Gun;Jo Young-Suk;Kim Ji-Young;Im Jeong-Cheol;Chon Hee-Woong;Yang Hong-Ji
    • Korean Journal of Veterinary Service
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    • v.29 no.1
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    • pp.65-70
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    • 2006
  • In order to detection of the intestinal parasites, fecal samples were taken from broiler (n=290), parent stock (n=168) and laying hen (n=114) in Jeonbuk province. The prevalence and identification of intestinal parasites were determined by the fecal examination using the floatation method and microscopical examination, respectively. The detection rate of parasite-eggs from 3 flocks (total=572) was 44.9%. In the breed and type of breeding, infection rate of parasite-eggs was detected 65.5% as broiler (floor breeding, 290 chickens), 20.2% as parent stock (floor breeding, 168 chickens) and 28.9% as laying hen (cage breeding, 114 chickens), in order. In the concern of mixed infection such as single and double, the rate were 40.7% and 4.2%, respectively. Six kinds of infective eggs were isolated 257 fecal sample from 3 flock. They were classified 74.7% as Eimeria spp, 18.1% as Ascaridia galli and 6.0% as Capillaria spp and 0.4% as Heteratkis gallinarum, Railleina spp or Trichostrongylus spp, single or in combination.

Stability of onshore pipelines in liquefied soils: Overview of computational methods

  • Castiglia, Massimina;de Magistris, Filippo Santucci;Napolitano, Agostino
    • Geomechanics and Engineering
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    • v.14 no.4
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    • pp.355-366
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    • 2018
  • One of the significant problems in the design of onshore pipelines in seismic areas is their stability in case of liquefaction. Several model tests and numerical analyses allow investigating the behavior of pipelines when the phenomenon of liquefaction occurs. While experimental tests contribute significantly toward understanding the liquefaction mechanism, they are costly to perform compared to numerical analyses; on the other hand, numerical analyses are difficult to execute, because of the complexity of the soil behavior in case of liquefaction. This paper reports an overview of the existing computational methods to evaluate the stability of onshore pipelines in liquefied soils, with particular attention to the development of excess pore water pressures and the floatation of buried structures. The review includes the illustration of the mechanism of floating and the description of the available calculation methods that are classified in static and dynamic approaches. We also highlighted recent trends in numerical analyses. Moreover, for the static condition, referring to the American Petroleum Institute (API) Specification, we computed and compared the uplift safety factors in different cases that might have a relevant practical use.

Prevalence of Parasite Infection of Swine at the Sawdust Fermentative Pigsty in Chonbuk District (전북지방 톱밥발효돈사 사육돈의 내부기생충감염조사)

  • 양홍지;서창섭;윤여백;박태욱;최은영;김성훈
    • Korean Journal of Veterinary Service
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    • v.17 no.1
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    • pp.25-31
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    • 1994
  • In order to investigate the internal parasitic infection, fecal samples were collected from weaning pig(n=123), porker(n=418) and sow(n=121) in 49 sawdust fermentative pigsty of Chonbuk district. The prevalence and identification of internal parasites were determined by the fecal examination using the floatation and /or sedimentation methods and microscopical examination, respectively. The results were obtained as follows ; 1. The detection rate of parasite - eggs from 662 fecal samples was 86.6%. 2. The infection rate of parasite-egg 96.4% in porker, 76.9% in sow, 62.6% in weaning pig, in order. 3. In the concern of mired infection such as single, double triple and quadraple, the rate was 42.3%, 28.7%, 12.2% and 3.3%, respectively. 4. Ten kinds of the detected eggs were isolated from 662 fecal samples. They were classified as Balantidium coli (63.6%), Trichuris suis(24.8%), isospora spp.(23.5%), Oesoohangostomum spp.(17.8%), Ascaris suum(11.8%), Hyostronylus rubiddus (2.8%), strongyloides spp. (1.7%), Gnathostoma spp. (1.5%), Stephanurus dentatus(1.3%) and Metastrongylus spp. (0.7%), in order.

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Effect of the anti-parasitic activity treated with conventional medicine-acupuncture (기생충증에 대한 전통의술(침술)의 치료효과 비교)

  • Youn, Hee-Jeong;Noh, Jae-wuk;Oh, Hwa-gyun;Hong, Ki-ok;Lee, Joo-myoung;Yoon, Young-min
    • Korean Journal of Veterinary Research
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    • v.38 no.1
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    • pp.133-137
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    • 1998
  • To investigate the effect of acupuncture on bovine parasitosis, we first surveyed the prevalence of parasite by fecal sedimentation and floatation techniques, and Giemsa stain for blood parasites. Coccidia were the most frequent parasite(22.1%), which followed by Buxtonella sulcata. Others were very few. After acupuncture, infection rates of Coccidia and B sulcata started to decrease at 1 day after acupuncture(DAA) and reduced to 5.3% and 0% at 7 and 21 DAA, respectively. In comparison between treated and control groups, due to small sample number, statistical evaluation was impossible. But diarrhea of treated group was slightly decreased, while, haemoparasites infection rate is decreased in control group. To gain the confident result of acupuncture effect, the more investigation is needed.

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The treatment of sewage using DAF pump system with micro bubble and non-powered flotation tank (응집제 자동혼합형 미세기포 발생장치와 무동력 부상분리조를 이용한 하수의 처리)

  • Kim, Dong-Ha;Lee, Soo-Young;Jung, Eui-Taek
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.5
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    • pp.659-666
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    • 2011
  • Although DAF(Dissolved Air Flotation) has been successfully accepted for water and wastewater treatment, the fundamental characteristics of the process have not been fully investigated. Water is saturated with compressed air to dissolve the air into the water at high pressure in saturation tank. Then the water containing dissolved air is released into a floatation tank at a lower pressure, generating micro-bubbles that rise gently through the water and carry the suspended matter to the surface. This study investigated the removal of sewage using automatic mixture type DAF pump and non-powered flotation tank. Characteristics of two devices were compared and analyzed with samples. The results showed that the PAC exhibited higher performance than other coagulants. When air dosage was 2.5ml/l/min, treatment was stable in operation. In the DAF pump with a pressure of 4 atm., the average size of bubbles was 36.2${\mu}m$. Removal efficiency of SS was 80%. At this time removal efficiency of COD was about 80%, of T-N was 30% and T-P was 70% in stable operation. It was concluded that DAF pump system with micro bubble performed higher efficiencies compared to general DAF system for treating wastewater.

Prevalence of Intestinal Parasites Infection of Dogs in Chonbuk Province (전북지방 개의 장내기생충 감염실태)

  • 양홍지;윤여백;이흥재;최인방;박태욱;서창섭
    • Korean Journal of Veterinary Service
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    • v.15 no.1
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    • pp.7-16
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    • 1992
  • In order to detection of the Intestinal parasites, 503 fecal samples were taken from mongorel-and pad-dogs in Chonbuk province. The prevalence and identification of intestinal parasites were determined by the fecal examinations using the floatation and /or sedimentation methods and microscopical examination, respectively. The results were obtained as follows 1. Fifty-nine percent (297 dogs) from 503 fecal samples were detected eggs. In seasonal detection rate of eggs, Summer was 30.3%, Autumn 26.4%, Winter 22.3% and Spring 21.0%, in order, 2. A total of 20 kinds of eggs were isolated from feces, and it was identified 75.7% as Nematoda(320 dogs), 5.6% as Cestoda(24 dogs) and 1.4% as Trematoda(6 dogs), and 17.2% as Protozoa(73 dogs). The isolates were identified as Ancylostoma caninum (30.4%, 153 dogs), Isospora spp. (14.3%, 72 dogs), Toxocara canis(11.1%, 56 dogs), Toxascaris leonina(5.8%, 29 dogs) , Uncineria stenocephala or Physaloptera spp. (5.4%, 27 dogs), Trichuris vulpis(2.4%, 12 dogs) and the others, single or in combination. 3. In mixed infection such as single, double, triple and quadraple was 63.6%, 31.7%, 3.4% and 1.3%, respectively.

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A survey on gastrointestinal parasites of Korean water deer (Hydropotes inermis agyropus) in Chungbuk province (충북지역 야생 한국고라니의 내부기생충 감염률 조사)

  • Choe, Seong-Jun;Na, Ki-Jeong;Jee, Cha-Ho
    • Korean Journal of Veterinary Service
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    • v.34 no.3
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    • pp.259-263
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    • 2011
  • Wildlife has been recognized that has important role as reservoir hosts of disease affecting both people and livestocks. However, information intestinal helminths of Korean water deer were limited. We obtained 20 feces from Korean water deers that were transferred to veterinary hospital in Chungbuk National University from May 2010 to June 2011. Parasite ova were collected using saturated zinc sulfate floatation method. Parasite eggs were examined and measured using light microscope. The identification of parasitic eggs was done by morphological characters. The overall infection rate of parasite was 85% (n=17). The eggs were observed as being Nematodirus spp. (n=14), strongyles egg (n=11), Capillaria spp. (n=9), Trichuris spp. (n=7), Eimeria spp. (n=4), Ogmocotyle spp. (n=3), and Strongyloides (n=1). Mixed infection rate was observed as being single 15% (n=3), double 20% (n=3), triple 15% (n=3), quadruple 30% (n=6), and quintuple 5% (n=1). The Ogmocotyle spp. was first reported in Korea.