• Title/Summary/Keyword: small vessels

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A study on hull form design for small fishing vessels (소형어선의 선형설계에 관한 연구)

  • Kim, In-Seob;Go, Dae-Gyu;Park, Dong-Woo
    • Journal of Advanced Marine Engineering and Technology
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    • v.41 no.4
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    • pp.316-322
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    • 2017
  • The primary objective of the current study is to develop outstanding hull form on resistance performance by using numerical analysis code. Model tests were conducted to assess the resistance performance of the developed hull form. The investigation of an existing vessel was performed for validating the actual ship design based on the drawing. The operating displacement and speed were mainly confirmed through investigation of the existing vessel. The resistance performance of the existing vessel was analyzed using numerical code. The developed vessel was derived through studies on wave improvement of the bow shoulder, the balance of displacement distribution, the modification of the frame shape, and the size and shape change of the center skeg. Based on the results of a computational fluid dynamics analysis, the resistance performance of the developed vessel showed an improvement of 15% over the existing vessel at a speed of 11 knots. Resistance tests were conducted to evaluate the performance of the existing vessel and the developed vessel in the towing tank. Finally, the effective horsepower of the developed vessel showed an improvement of 17% over the existing vessel.

Algicidal Effects of a Newly Developed Thiazolidinedione Derivative, TD49, on Dinoflagellate Akashiwo sanguinea (Thiazolidinedione 유도체(TD49) 물질을 이용한 적조생물 Akashiwo sanguinea의 제어)

  • Baek, Seung-Ho;Shin, Hyeon-Ho;Jang, Min-Chul;Kim, Si-Wouk;Son, Moon-Ho;Cho, Hoon;Kim, Young-Ok
    • Ocean and Polar Research
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    • v.34 no.2
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    • pp.125-135
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    • 2012
  • To evaluate the algicidal impact of a newly developed algicide thiazolidinedione derivative, TD49, on dinophyceae Akashiwo sanguinea in aquatic ecosystems, tentative culture experiments for the target species were conducted in small (SS), middle (MS), and large scale (LS) culture vessels. When TD49 was introduced at the final concentration of $2{\mu}M$ in SS and MS, as well as $1{\mu}M$ in LS, the abundance of A. sanguinea decreased significantly in all the treatments. On the other hand, total phytoplankton abundance, except A. sanguinea in the TD49 treatments, gradually increased with culture time, which implies that a cell destruction of A. sanguinea by TD49 is a major cause of the population growth by other phytoplankton species. Also, A. sanguinea was easily destroyed, which was likely to be a source of extracellular substances. In particular, a pH decrease was significant in the treatments than in the control, which indicates that the water in the treatments has been acidified, due to an increase in the heterotrophic metabolisms of bacteria and degradation of A. sanguinea cells. Our results indicate that the TD49 substance is the potential agents for the control of A. sanguinea in the enclosed and eutrophic water bodies.

Treatment of refractory IgA vasculitis with dapsone: a systematic review

  • Lee, Keum Hwa;Hong, Sung Hwi;Jun, Jinhae;Jo, Youngheun;Jo, Woogyeong;Choi, Dayeon;Joo, Jeongho;Jung, Guhyun;Ahn, Sunghee;Kronbichler, Andreas;Eisenhut, Michael;Shin, Jae Il
    • Clinical and Experimental Pediatrics
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    • v.63 no.5
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    • pp.158-163
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    • 2020
  • IgA vasculitis, formerly known as Henoch-Schönlein purpura, is a systemic IgA-mediated vasculitis of the small vessels commonly seen in children. The natural history of IgA vasculitis is generally self-limiting; however, one-third of patients experience symptom recurrence and a refractory course. This systematic review examined the use of dapsone in refractory IgA vasculitis cases. A literature search of PubMed databases retrieved 13 articles published until June 14, 2018. The most common clinical feature was a palpable rash (100% of patients), followed by joint pain (69.2%). Treatment response within 1-2 days was observed in 6 of 26 patients (23.1%) versus within 3-7 days in 17 patients (65.4%). Relapse after treatment discontinuation was reported in 17 patients (65.4%) but not in 3 patients (11.5 %). Four of the 26 patients (15.4%) reported adverse effects of dapsone including arthralgia (7.7%), rash (7.7%), and dapsone hypersensitivity syndrome (3.8%). Our findings suggest that dapsone may affect refractory IgA vasculitis. Multicenter randomized placebo-controlled trials are necessary to determine the standard dosage of dapsone at initial or tapering of treatment in IgA vasculitis patients and evaluate whether dapsone has a significant benefit versus steroids or other medications.

Development of animal welfare type headgear in the case of fighting bulls (싸움소의 증례를 통한 동물복지형 헤드기어의 개발)

  • Kim, Tac-Suk;Kim, Chung-Hui
    • Korean Journal of Veterinary Service
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    • v.38 no.4
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    • pp.253-257
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    • 2015
  • Bull-boxing in South Korea is a form of competitions in which bulls measure their strength with each other in the form of pushing by putting their heads together. Bull-boxing has been admitted after being designated as a play culture by the government because it does not cause great injuries to animals' bodies and has strong positive aspects such as contributing to livestock farmers' leisure activities, encouragement of animal husbandry, and communities' economic development. However, bull-boxing sometimes causes damage to the head and horns due to the heavy bodies. According to the results of examinations of these damage cases, damage that caused irregular shapes of the base of horns was identified in 31.5% of fighting bulls. The damage to horns is thought to have been caused by the great forces of fighting bulls repeatedly imposed to each other's horns during bull-boxing that caused minute fractures leading to damage to the blood vessels inside the horns resulting in the blocking of delivery of nutrients to the horns causing the deformation of the horns into abnormal shapes. Since bulls' bodies are injured during bull-boxing although the injuries are small as bull-boxing is mainly conducted by pushing, animal protection groups regard bull-boxing as cruelty to animals and request to stop bull-boxing. The present study aims to develop animal welfare type headgears that can protect bulls' horns and heads in order to protect fighting bulls during bull-boxing in terms of animal protection and welfare.

An Experimental Study for Radiation Nephritis in Rabbits (가토(家兎)를 이용(利用)한 방사선신염(放射線腎炎)의 실험적(實驗的) 연구(硏究))

  • Kim, Myung-Jae
    • The Korean Journal of Nuclear Medicine
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    • v.6 no.2
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    • pp.7-20
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    • 1972
  • Experimental radiation nephritis was produced in 15 rabbits by X-irradiation. About $2,000{\gamma}$ (tissue doses) were given to both kidneys of a rabbit in 5 days. Other tissues and organs except both kidneys were protected with 2mm thickened lead plates. 5 weeks after the last irradiation, blood pictures, blood pressures, B.U.N., serum creatinine, Ca, Mg, Fe levels and serum erythropoietin activity of the irradiated rabbits were studied. After finishing above studies, rabbits were sacrificed and both kidneys were removed and examined histopathologically. Same laboratory and pathological studies were performed in 6 control rabbits. In this study, the author obtained following results. 1) Both kidneys of rabbitis with experimental raditation nephritis showed marked histopathological changes, i.e.: renal tubules showed diffuse cloudy swelling, impacted intraluminal hyaline casts and focal precipitations of lime salts on the tubular epithelium. Diffuse interstitial fatty necrosis and various degrees of fibrotic infiltrations on the interstitium were also seen in association with focal lymphocytic infiltrations. Hyaline degenerations were observed on the glomeruli and small vessels. 2) Experimental radiation nephritis rabbits showed marked lowering in R.B.C. counts, decreased hemoglobin levels, low hematocrit values and leucopenia in comparison with those of control rabbits. (P<0.01). (Table 1 & 2). 3) Mild proteinuria were observed in experimental radiation nephritis in rabbits. 4) The levels of B.U.N. and serum creatinine increased in experimental radiation nephritis. (P<0.01). (Table 1,3 & 4) 5) The levels of serum Ca and Mg Showed no statistical difference in comparison with those of control rabbits. (P>0.05) (Table 3 & 4). 6) No statistical correlations were observable between the levels of B.U.N. and Hb. values. (${\gamma}=-0.223$) No close correlations (${\gamma}=-0.328$) were noticed between the levels of B.U.N. and serum iron levels. 7) Erythropoietin activity (R.B.C. $^{59}Fe$ Incorporation) was measured by the modified Fried method. No change in its activity was noticed in radiation nephritis group comparing with that of the control group. (P>0.05). (Table 1,3 & 5). 8) Carotid artery blood pressures showed also no difference. (P>0.05). (Table 1 & 2).

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A Morphological Study on the Macrophages During Luteolysis in the Pig (돼지 황체에서 황체용해와 대식세포와의 관계)

  • 김원식;한승로;손성경;박창식;양윤석
    • Journal of Animal Science and Technology
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    • v.48 no.2
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    • pp.191-202
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    • 2006
  • In addition to the removal of dying or dead lutein cells by phagocytosis in many species, macrophages exert both luteotropic effect during maturation period and luteolytic effect during degenerative period via mediating autocrine/paracrine actions of self-producing cytokines in the corpus luteum. In this experiment, immunohistochemical and transmission electron microscopic (TEM) studies were performed to observe the morphologic changes of luteal macrophages during luteolysis. A small number of macrophages and low immunoreactivity were present at the mature stage. The number of macrophages and immunoreactivity gradually increased along the advance of luteolysis. Two subtypes of macrophages could be observed through TEM observation. One type of macrophage located between the large lutein cells contained no lipid droplets in their cytoplasm at mature stage. The other type of macrophage located near the blood vessels contained many lipid droplets in their cytoplasm during luteolysis. Particularly, no phagocytic macrophages were observed, which suggested the macrophages in the porcine corpus luteum did not involve in the phagocytotic elimination of dying lutein cells.

Octopus fisheries in the coastal waters of Gangneung - I - Pot fishery - (강릉시 연안 문어어업에 관한 연구- I - 통발어업 -)

  • An, Young-Il;Park, Jin-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.4
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    • pp.271-278
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    • 2005
  • In order to study the catch situation of the octopus pot fishery in the coastal waters of Gangneung, catch quantities and weight per month and depth, the soaking time & loss of fishing gear were studied based on 62 fishing times (1 set consisted of 150 pots which is equivalent to 1 fishing time) over a period of 10 months from February to December 2003 using commercial fishing vessels and training ships. The monthly CPUE was generally high in the months of june - September, and during this period July showed the highest quantity (134g/pot, 19.21kg/haul). In consideration of the fact that octopus below the weight of 2kg is protected in foreign countries, the majority of the catch was small with 76% (486 octopuses) below 1kg. The octopus catch quantity was high in depth of more than 40m, and the average catch number per set of pots in depths of over 50m was the highest with 13 octopuses. CPUE(g/pot) was the highest at a depth of over 60m recording 101. In terms of catch quantity per soaking time (4-18 days) the highest was on the 7th day, and 13-18 days also recorded high catches, and this suggests the possibility of ghost - fishing with the loss of fishing gear. Loss of fishing gear was the highest in terms of loss frequency and amount at depths of 20-30m. Consequently, it seems that octopus pot fishing at depths of more than 30m would relieve friction with other types of fishing and increase fishing efficiency.

Distribution of Anchovy , Engraulis Japonica ( Houttuyn ) , in the Coastal Waters of Kangwon Province in Korea (강원 연안 멸치의 분포 특성에 관하여)

  • 박종화
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.3
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    • pp.223-234
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    • 1996
  • Distribution of Anchovy was analyzed from the experimental operations by the small anchovy drag net fishery in the coastal area of Yang yang - gun and Myongju - gun of Kangwon Province from October to December, 1994. Temperature ranged from $11.4^{\circ}C.$to $17.4^{\circ}C.$throughout the experimental period. Fishes caught by experimental operation vessels were composed of anchovy, Clupanodon Punctatus, Pleuronectidae, Tetraodantidae, Acanthopagrus Schlegeli etc., and the anchovy occupied more than 99.6% of the total catch. Anchovy was characterized by the most abundance of the catch for the individual less than 6cm and the gradual increase after October for those larger than 6cm. CPUE(catch per tow) of anchovy was 684kg in October, 784kg in November, 1,590kg in December and mean CPUE of 3 months from October to December was 1,066kg. Fishing grounds of anchovy were formed in coastal area, from $37^{\circ}$45'N to $38^{\circ}$04'N, off Kangwon Province. Distribution density of anchovy in Chumunjin - up, Kyohang - ri Sachon - myon, and Sachonjin - ri coasts was higher than the other areas. Anchovy caught in this surveyed area was recruited from July to September at the length class between 2cm and 3cm, and grew to the sizes between 4cm and Bem in October, between 5cm and tcm in November, between tcm and Bem in December. Recruitment of anchovy increased from July to September and suddenly decreased after September. Individual number of the population was the largest during the period from August to October and gradually decreased after October. Biomass continuously increased after August, and was the largest in December.

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Indications and Prognostic Factors of Groin Flap for Reconstruction of the Extremities (사지 재건에 있어 서혜부 유리 피판술의 적응증 및 예후 인자)

  • Kim, Bo-Ram;Hahn, Soo-Bong;Kang, Ho-Chung;Choi, Yun-Rak;Kim, Sun-Yong
    • Archives of Reconstructive Microsurgery
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    • v.18 no.2
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    • pp.41-48
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    • 2009
  • There are several advantages for groin flap, but its small and unpredictable vessels of pedicle have made it to lose its initial popularity. Although it would be ideal flap when it is focused on its useful advantages such as relative larger size, low donor site morbidity and possible bone graft, there have been few studies for prognostic factors for successful groin flap. Authors intended to determine prognostic factors which are relative with success of free groin flap. From January 1985 to December 2007, 107 patients who underwent groin flap for reconstruction of extremities were selected consecutively. Univariate and multivariate analysis were performed to determine prognostic factors which were related with success of groin flap. Eighty of 107 (74.8%) flaps survived. There was significant difference in success rate according to the recipient site. Nineteen of 20 cases (95%) survived in upper extremities, but 61 of 87 cases (70.1%) survived in lower extremities, which was statistically significant (p=0.022). Univariate analysis showed that mean diameter of donor veins was significantly larger in success group (p=0.021). Groin flap is recommended for reconstruction of upper extremities than lower extremities. It is thought to be critical that surgeons try to match vessel diameters between donor and recipient site.

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A Study on the Requirement to the Fishing Vessel for Reducing the Collision Accidents (충돌사고 감축을 위한 어선의 대응 방안에 관한 연구)

  • Jung, Chang-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.1
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    • pp.18-25
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    • 2014
  • In spite of being reduced the numbers of vessel registered, there are increasing the numbers of total marine accidents and collision accidents. For recent 5 years from 2008 to 2012, it was analyzed that the collision accident is highest rank by 37 % among the marine accidents and the fishing vessel is highest by 58 % in these collision accidents and also the small fishing boat under 20tons is highest by 26 % on them. Over the half of the collision accidents by 56 %, they couldn't find each other to just before the collision situation. In this result, it was known that collision accidents almost to be occurred by the poor look-out in each other. Therefore, it was suggested the requirements to the fishing vessels in a side of crew, education and exercise, and navigation equipments to reduce the collision accidents by examining the navigation patterns and concerning laws of them.