• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.115-118
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• 2000

The production of cultured coho salmon (Oncorhpchus kisutoh) in Korea has being increased year after year. Smolt being reared in freshwater suffer transferring into seawater and are farmed in cages for fattening. This handling processes including transportation, confinement into cages are unavoidable stress to fish in salmon farming and often end up to mass mortality, This study aimed to investigate the impact of handling process on the stress responses of coho salmon. The indicator of stress was measured by cortisol to be a first response, and for the second response test, glucose, triBlyceride, cholesterol, lactate and electrolyte of $K^+, Na^+, Cl^-$ in serum and the activities of alanine aminotrtnferase (ALT), aspartate aminotransferase(AST) and lactate dehydrogenase (LDH) were analyzed. As a result, the concentration of cortisol, glucose as well as LDH activity were significantly increased, whereas others showed no difference comparing with control group. It obviously demonstrated that handling process made fish stressful.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.334-342
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• 2010

The purpose of this study is conducted to examine the change of flora and fauna in the extensive rooftop green area from 2005 to 2009. The experimental site is on the rooftop green area of Seoul Women's University which was constructed in 2005. This research was consisted of four parts: soil, potted plants, invading plants and small animals especially insects. The plants were surveyed by enumeration, while animals were surveyed by two methods which are 'Netting and Searching' and 'Pit fall trap'. The initial group of plants planted in 2005 was 100 species of 26 families whereas in 2009 there were 62 species of 23 families including 22 invading species of 11 families. In case of insects in 2009, 21 species of 7 families (9 orders) were detected; 19 species of 15 families (8 orders) were discovered by 'Netting and Searching' and 5 species of 5 families (5 orders) by 'Pit fall trap'.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.7-10
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• 1975

The catches of mackerel by monofilament and multifilament net were compared by means of $x^2$ and t-test method. In order to improve the netting twine of drift nets, 6 shoots 5 different mesh and nylon-monofilament netting twines $(B\times2,\;C\;D,\;F,)$ and 2 shoe nylon-multifilament $(A\times2)$ which are using near the Jeju Island in contemporary days were used for the experiment. These gill no were connected in order of A, ,B, C, A, B, E, F and operated fly fishing boat Taeann Ho (7T) near sea of Jeju Ialand from May 1974 to August 1974. The results obtained are as follows: 1. B type nylon-monofilament gill nets were superior to nylon-multifilament gill nets in catch according to the result of $X^2$ test and t-test, and the catch ratio was $M_A:\;M_B=1:1.8$. 2. 75mm mesh size C, D nylon-monofilament gill nets were superior to 85mm mesh size nylonmonofilament gill nets, and their catch ratio were E, F: C, D=1:2.8. 3. The catch ratio C, D and E, F type nets were compared by means of t-teat, however could not recognized their relationship.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.177-184
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• 1987

The quantitative mechanics on the sideways walking of the crabs may provide a basic solution for entanglements of the walking legs in gillnets. The gaiting behaviour of the crabs on the flat board and the nettings 10, 16 and 23 mm in mesh size were experimented concerning about stepping positions and times in the laboratory using video set on July, 1984, It was found that the irregular movements of walking crabs in stepping positions and patterns were appeared on the nettings due to the absence of mechanical contact in spite of neural control of compensating, while on the flat surface evolved systematic leg movements. The mean stride length and walking velocity, which were increased with the carapace width on the flat board, as well as the step period and forward by backward stroke time were greater than those values on the netting, not associated with the carapace or the mesh size. Also, the step period and the Phase difference on the nettings revealed larger fluctuation than on the flat board. The joint angles of the walking legs, on the nettings in meropodite-carporodite and thorax-meropodite, which joint was varied especially up to below horizon because of the falling legs through the netting twine, were virtually wider than those on the flat substrate.

• Journal of Fisheries and Marine Sciences Education
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• v.6 no.1
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• pp.11-19
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• 1994

The North Pacific midwater trawling which is one of the important fishing methods for Korean fishing industry is working in the Bering Sea and the sea near Kamchaka Peninsula. The catch by Korean midwater trawlers had been recorded about 300 thousands $^{M/_T}$ a year. Six types of midwater trawl net-ordinary midwater trawl net, super-V trawl net, super mesh trawl net, rope trawl net, super plus trawl net and kite trawl net-have been widely used by large trawlers above 1,500gt in size since 1982. Regarding the fishing efficiency, the super plus trawl net and kite trawl net were acknowledged as higher than other nets. Maximum mesh size of super-plus trawl net and kite trawl net ranges about 20m, whereas the length of net about 150m, and high-tech polyethylene is used as the material of rope part. The problems involved in the North Pacific midwater trawl net may be summarized as follows ; (1) The dimension of fishing gear is too big compared with the towing power of trawler. (2) The mesh size of the rope part is too big compared with that of the common netting part. (3) The net is often torn out in the connecting position of the rope part and the netting part. (4) The net is not matched with the trawler and the otter board in many trawlers, so the shape of the trawl gear in the water is instable. (5) The fish school located near head rope, ground rope and side rope in the net recorder is not caught in practice because of the net instability.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.287-293
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• 1998

Floating debris was recorded from a training ship, #1 Kwarnksan, of Pukyong National University with about 10 knots speed during March, May and July of 1997. The area sampled is the Southeastern Coast of Korea, divided into 40 unit segments on survey routes. Debris fabrication materials were categorized using the following ; man-made or natural wood items, paper, cardboard, nylon rope, netting, styrofoam and plastics, floating metal and glass containers. All identified items within a $100\;{\pm}\;2\;m$ wide band were recorded but ignored if beyond this boundary.The results of distribution and composition of floating debris in the area as follows:1. The quantities of debris during the duration of survey were distributed from 2~605 items per km2. The most obvious trend is the widespread distribution of all debris. 2. The highest densities of all debris were discovered in the coastal waters of Seoimal lighthouse, the southeastern part of Koje island, next near Nakdong estuaries. Especially styrofoam & plastics were observed in 77.4~87.2% of sampled area, next is wood items, 9.1~ 13.5%. And nylon netting & rope, 3.6%, was the third item of pollutant. Others are very small. 3. Compared with the East Coat of Korea, the quantities of all debus in theSoutheastern Sea are 6 times as large as the East Coast. The survey provides a basis for more detailed survey work in the South Sea. Further surveys are being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the removal method, finding of sources, stationary area of debris.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.1
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• pp.31-39
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• 1997

Floating debris was recorded from a training ship, #1 Kwanaksan, of Pukyong National University with about 10 knots speed during August 19~26, 1996. The area sampled is the East Coast of Korea, divided into 33 unit segments on survey routes. Debris fabrication materials were categorized using the following; man-made or natural wood items, paper, cardboard, nylon rope, netting, styrofoam and plastics, floating metal and glass containers. All identified items within a $100{\pm}2m$ wide band were recorded but ignored if beyond this boundary. The results of distribution and composition of floating debris in the area are as follows: 1. The quantities of debris during the summer were distributed from 1.8~52 items per $km^2$. The most obvious trend is the widespread distribution of all debris. 2. The highest densities of all debris were discovered in the vicinity of Pusan and ills an area. Especially styrofoam & plastics were observed in 81% of sampled area, next is wood items, 9.1%. Nylon netting & rope was the least widespread pollutant. 3. The relationship between distribution of debris and surface currents of the area was not apparently revealed through this survey. Further surveys are being instigated, and from this it is hoped that a much wider coverage can be achived, perhaps on all sites of Southern and Western sea of Korea and contributed to the finding of sources,stationary area of debris.

• Ocean Systems Engineering
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• v.7 no.2
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• pp.143-155
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• 2017

For complex flexible structures such as nets, the determination of drag forces and its deformation is a challenging task. The accurate prediction of loads on cages is one of the key steps in designing fish farm facilities. The basic physics with a simple cage, can be addressed by the use of experimental studies. However, to design more complex cage system for various environmental conditions, a reliable numerical simulation tool is essential. In this work, the current load on a cage is calculated using a Morison-force model applied at instantaneous positions of equivalent-net modeling. Variations of solidity ratio ($S_n$) of the net and current speed are considered. An equivalent array of cylinders is built to represent the physical netting. Based on the systematic comparisons between the published experimental data for Raschel nets and the current numerical simulations, carried out using the commercial software OrcaFlex, a new formulation for $C_d$ values, used in the equivalent-net model, is presented. The similar approach can also be applied to other netting materials following the same procedure. In case of high solidity ratio and current speed, the hybrid model defines $C_d$ as a function of Re (Reynolds number) and $S_n$ to better represent the corresponding weak diffraction effects. Otherwise, the conventional $C_d$ values depending only on Re can be used with including shielding effects for downstream elements. This new methodology significantly improves the agreement between numerical and experimental data.

• Journal of Fashion Business
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• v.4 no.3
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• pp.115-129
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• 2000

The purpose of this study is to discover the techniques and the trends of expression of modern knitwears focusing on the 1990's after. The resorts of this study is as follows: The techniques of expression of knitwears are classified by the sections on the techniques and the styles of expression. The divisions into the techniques are knitting, crochet, macrame, netting, knotting. And the divisions into upon the styles of expressions are color, pattern, texture, relief and seeing through The techniques of expression on the modern knitwears are expressed characteristic of variety and composition, are expended to the art wear by translated into art. According to a wide sense, ecology, ethnic, modern are the themes of knitwears of 1990's after. The characteristic technique of expression according to the themes are expressed by the harmony of image, yarn, color, silhouette, techniques of expression. The modern knitwears are tried by mixed and various techniques, developed to the area of art wear, escaping from simple and practical item.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1029_1030
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• 2009

본 논문에서는 빔 에너지를 이용하여 내 마모 및 내 부식성을 갖는 철망을 가공하여, 빔 에너지 조사 전과 후의 SEM 사진과 인장강도를 측정하여 비교, 분석 하였다. 전자빔으로 표면을 개질하기 전보다 후의 표면이 더 치밀해짐을 SEM사진을 통하여 볼 수 있었고, 인장강도를 측정 하여 개질 전과 후를 비교 하였는데, 인장강도와 관련된 탄성계수가 더 크게 나타나 전자빔 조사에 의한 샘플이 긴 수명을 갖는 요인이 분석되었다.