• 한국해양학회지
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• 제6권2호
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• pp.104-106
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• 1971

표식율법을 이용하여 어족으 자원량을 추정하는 방법에 대하여는 많은 연구보고가 있다(Ricker, 1948; Schaefer, 1951; Delury, 1958; Nose, 1961). 그런데 표식율법으로 자원미수를 추정할 경우 다음과 같은 몇가지 조건이 수반되어야 편의성이 없는 추정치를 얻을 수 있다. 즉 표식의 탈락이 없으며, 표식어는 위약성과 자연사망에 있어서 비표식어와 차이가 없으며, 가입과 일출이 없는 모집단에서 임의표본이 추출되어야 하며, 표본중의 표식어의 판명이 완전하여야 한다. 본고에서는 연어의 산란친어미수를 표식율볍으로 추정함에 있어서 당면하는 문제점 특히 일출이 있을 경우와 천적으로 인한 표식어의 오판이 있을 경우에 대하여 검토한 결과를 보고한다.

• Parasites, Hosts and Diseases
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• 제56권3호
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• pp.267-274
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• 2018

Aim of the present study was to provide presence of opisthorchiid metacercariae in cyprinid fish Leuciscus idus in Nura-Sarysu river, Kazakhstan. Infection rate of the ides by the metacercariae was 42%. The metacercariae, similar morphologically to those of the liver flukes, were found: elliptical in shape, $0.19-0.25{\times}0.15-0.22mm$, oral and ventral suckers nearly equal size, and excretory bladder O-shape with black content, occupying posterior part of the body. The metacercariae were divided into 2 groups with differences in size and thickness of cyst wall. Adult flukes were recovered from the Syrian hamsters infected with the opisthorch metacercariae and identified with morphological characters to Opisthorchis felineus and Metorchis bilis. DNA sequences of ITS1, ITS2, and cox1 supported the taxonomic assignment.

• 수산해양기술연구
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• 제46권4호
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• pp.358-367
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• 2010

Feeding habits of Acentrogobius pellidebilis collected from in an eelgrass(Zostera marina) bed from January to December 2006 were studied. A. pellidebilis ranged form 1.6 to 6.9 cm in standard length were determined. A. pellidebilis was a carnivore which consumed mainly copepods, polychaetes, and amphipods. Its diets included small quantities of isopods, seaweeds, nematods, and gastropods. It showed ontogenetic changes in feeding habits. Smaller individuals (<2.0cm SL) fed mainly on copepods. While the consumption of copepods decreased with increasing fish size, the consumption of polychaetes and amphipods were increased. Dietary breadth index was varied with fish size.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.177-181
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• 2005

Fishing selectivity is determined by the level of voluntary escaping behavior in accordance with decision-making based on the relationship between fish size and mesh size. This study examined movement during the swimming behavior of black porgy in a trawl's towing cod-end and analyzed the movement components such as swimming speed, angular velocity of turning, and distance to the net over time. Most of the observed fish exhibited an optomotor response, maintaining position and swimming speed without changing direction. Others exhibited erratic or 'panic' behavior with sudden changes in swimming speed and direction. The latter behavior involved very irregular and aperiodic variations in swimming speed and angular velocity, termed 'chaotic behavior.' Thus, the results of this study can be applied to a chaotic behavior model as a time series of swimming movements in the towing cod-end for the fishing selectivity.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.595-596
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• 2001

A scanning electron microscopic study on the glochidium and glochidial encystment of Anodonta archefomis on the host fish Carassius auratus was conducted. The shape of the glochidium is apparently subtriangular and its average size is 270${\mu}{\textrm}{m}$ $\times$ 260${\mu}{\textrm}{m}$ $\times$ 145${\mu}{\textrm}{m}$. The glochidial shell valves are of the same size, kept together by a ligament of 50.4${\mu}{\textrm}{m}$ in length and 5.5${\mu}{\textrm}{m}$ in width. (omitted)

• Design & Manufacturing
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• 제12권3호
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• pp.55-59
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• 2018

In a multi-cavity mold having a runner layout of a fish bone structure, problems of unbalanced filling between cavities occur constantly. Unbalanced charging lowers the dimensional accuracy of a molded article and causes deformation after molding. To solve this problem, the gate size connected to each cavity is adjusted using the BGV (Balanced Gate Value) equation. In this paper, in order to solve the filling imbalance problem of the runner layout mold of fish bone structure through injection molding analysis study, we compared the charging imbalance phenomenon before and after improvement after adjusting the gate size by applying BGV equation. From the results of the molding analysis, the shrinkage ratio before and after the improvement of the molded article was improved by only about 0.08%. Based on these results, it was confirmed that the charging imbalance problem was not significantly improved even when the BGV equation was applied.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.196.1-196
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• 1999

No Abstract, See Full Text

• 환경영향평가
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• 제21권6호
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• pp.879-891
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• 2012

The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

• 한국산학기술학회논문지
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• 제18권2호
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• pp.390-397
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• 2017

외래어종의 유입은 토종어류의 감소 및 수중생태계의 교란을 가져올 수 있기 때문에 어류의 차단 및 관리 방안은 반드시 필요하다. 따라서 본 연구에서는 외래어종의 유입을 차단하기 위해 버블을 이용한 어류 차단 시스템을 개발하였으며 실험수로를 제작하여 차단 가능성을 평가하였다. 버블 발생장치는 공기압축기로 공기를 발생시켜 버블커튼을 만든 후 어류를 차단하는 시스템이며 실험어류는 국내 외래어종인 파랑볼우럭을 대상으로 하였다. 파랑볼우럭의 크기는 0.10 m ~ 0.15 m이며 수심은 0.70 m를 유지하였다. 실험수로의 유속은 어류의 유영능력을 고려하여 3단계로(0.20 m/s, 0.10 m/s, 0.05 m/s) 나누어 실시하였다. 실험 결과 파랑볼우럭은 버블 적용 전 70.07%가 상류로 거슬러 올라가려는 움직임을 보였으며 하류를 서식처로 생각해 움직임이 거의 없는 개체를 고려하면 어류 소상률은 더 높을 것으로 판단된다. 그러나 차단시설을 설치할 경우 대부분의 어류가 버블커튼에 의해 다시 하류로 회귀하는 움직임을 보여 차단효과가 매우 높게 나타났다. 특히 버블을 종료할 경우 빠른 시간 내 다시 상류로 거슬러 올라간 것으로 보아 버블을 이용한 어류 차단효과는 뛰어난 것으로 판단된다.

• 한국식생활문화학회지
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• 제12권5호
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• pp.573-582
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• 1997

The purpose of this study is to establish the one serving size of Korean Processed Food. Defining the one serving size is very important for nutrition labeling and foodservice operation, because the one serving size is used to set up a proper portion by each foodservice operation. The basic data of 200 items were collected through three methods. Searching many cookbooks, exploring the commercial and noncommercial foodservices -6 industrial foodservices, 100 nationwide elementary school foodservice recipes analysis, and 3 hospital foodservice systems as the samples - moreover, experimental cooking and sensory evaluation by trained panels were conducted to assess quantity preference of selected food items. All data were rearranged through food type, that is, main dish, side dish, dessert and health food. One serving sizes of processed foods showed wide variety according to the different menus that include selected food items. Therefore, means and ranges of serving size by three research methods were presented item by item. The results obtained were: 1. The Korean Processed Foods were dried and sugar adding and soused foods, and many of them used the natual processing methods. 2. There were wide varieties in the classification of main dishes, but many of them were cereals, noodles, and sugar products. One serving size of noodles were around $50{\sim}100\;g$, cereals were $20{\sim}40\;g$, which means the one serving size can be differenciated by the food usage. 3. According to the Food classification of side dishes, many of them were as following; natural dried foods, processed fish products, salted or sugar added foods, seasoned foods and sugar products. Moreover the Types of cooking in side dishes were almost culinary vegetables, teas, health foods and condiments, and soused fish products. 4. About desserts, they were almost teas and sugars, and the Types of cooking were teas, health foods and seasonings. 5. We can conclude that almost Korean Processed foods used the drying and soused processing methods for long-time preservation, but it can make the higher content of any special elements, such as sodium or carbohydrates.