• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.410-418
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• 2000

In general, the experienced diver go into the water to find out Pan Shell which is spontaneously generated and brought up at the depth of 25-30 meters in the slime along the bank of an inlet of western and southern sea. However, this searching system has caused some problems in terms of economical efficiency and riskiness of diver. To overcome such problems and enhance the competence capability of fishermen, a new Pan Shell searching system is required. If an onboard searching system as a substitute of the way of diving into the deep water to identify the existence of Pan Shell is developed, it would be greatly beneficial to fishermen. The purpose of this research is to develop a new searching system of Pan Shell by making use of 50-200 Khz Ultra Sonic Signal, A/D Converter and computer process program. Based on the fact that Sonic Signal between the soft part of slime and the hard part of sand, pebble and Pan Shell is different, the possibility of this system have been approved in some degree by this time of research. However, to utilize this new system, further research on the establishment of data base and sample data is required. With the theoretical knowledge, the systematic research on the searching capability of Ultra Sonic Signal will be continued to identify the influence against the sea water subject. In this research, signal will be analyzed according to the influence range, power and sensitiveness of Ultra Sonic Generator. In addition, the radius of Ultra Sonic Signal will be included. The experimental field work will be executed at Nockdong, Pulkyo and other places well known as a habitat of Pan Shell.

• Journal of Aquaculture
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• v.13 no.4
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• pp.317-323
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• 2000

Experimental cohorts of Mugil cephalus were divided into 5 groups : seawater~normal feed (SWN), acclimation to freshwater~normal feed (GFWN), acclimation to freshwater~salt feed (Gf\iVS), freshwater. normal feed (FWN) and freshwater-salt feed (f\iVS). Growth was faster in the SWN, Gf\iVS, and GFWN groups than in the f\iVS and FWN groups. Condition factor did not differ among the groups. Survival (92 %) of the juveniles was the highest in the Gf\iVS group; however, the others showed no significant difference. Moisture of FWN group was significantly higher than that of SWN group (P < 0.05). Potassium concentration was significantly higher in the SWN group than that of others (P < 0.05). It was highest (30 mmolfl) among the cohort of SWN.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.111-117
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• 2000

There were observed the histomorphological alterations such as chloride cell hyperplasia, branchial lamellar epithelial separation, the increased cellular turnover of chloride cells, glomerular shrinkage and blood congestion in rainbow trout (Oncorhynchus mykiss) during the seawater adaptation. The ultrastructure by scanning electron microscope (SEM) indicated that the gill secondary lamella of rainbow trout exposed to seawater, were characterized by rough convoluted surfaces during the adaptation. There were observed a large number of mitochondria with the elongate and well-developed cristae in chloride cells exposed to seawater by transmission electron microscope (TEM). The presence of two mitochondria- rich cell types is discussed with regard to their possible role in the hypoosmoregulatory changes which occur during seawater-adaptation. Glomerulus shrinkage and blood congestion were occurred higher in nephrons of seawater-adapted fish than those living in freshwater. Our findings demonstrated that rainbow trout tolerated moderately saline environment and the increased body weight living in seawater was relatively higher than that living in freshwater in spite of histopathological changes.

• Journal of Aquaculture
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• v.19 no.1
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• pp.14-18
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• 2006

The objective of this study was to evaluate food value and profitability of black porgy (Acanthopagrus schlegeli) cultured in freshwater. In fish flesh, muscular hardness of black porgy reared in freshwater $(9210{\pm}1215g/cm^2)$ was slightly lower than those of fish in seawater $(9987{\pm}6549g/cm^2)$, but there was no significant difference. Also, there was no difference between muscular strength of fish reared in freshwater and seawater. When the flesh qualities of black porgy reared in freshwater was compared with those of fish reared in seawater through the questionnaire, there were no significant differences between fish reared in freshwater and seawater in appearance, texture, taste and flavor. For 10 months of black porgy culture in fresh water, the gross profit in culturing from juvenile (5.5 g) to adult size (100g), and from adult to marketable size (400 g) were 24,000,000 won (30.0%) and 53,870,000 won (36.9%), respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.339-344
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• 2010

Oxygen depleted water mass can damage aquatic animals not only in direct way but also in indirect way by generating toxic substances including occurrence of hydrogen sulfide and ammonia which are also highly detrimental to animal life in the water mass. An oxygen dissolution device was developed, which makes turnover of the oxygen rich (over 20 mg/L) surface water down to the bottom where hypoxia is evident and tested the device in terms of oxygen recovery in the oxygen depleted bottom water. the device with turnover rates of $3.6\;m^2$/min at the liquid oxygen injection rate of 48~26.3 L/min could recover dissolved oxygen level to 7~25 mg/L at depth 7 m to lead to the dissolution level of over 90% by the supply of liquid oxygen. The running advantage of the device is that it does not require any auxiliary tank and higher energy for operation. Therefore, it can be highly useful device to relieve damages to the farmed animals in the oxygen depleted waters.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.15-16
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• 2003

이제 바다로부터 식량을 얻는 방법이 어선을 통해 포획하는데서 점점 연근해에서 양식을 통해 생산하는 쪽으로 선회를 하는 것이 세계적인 추세가 되어가고 있다. 이와 같은 양식업의 점진적 발전은 해수 환경을 보전하고 생산 비용을 절감할 수 있는 새로운 형태의 먹이(사료)를 요구하고 있다. 그러나 물고기의 먹이로 적합한 어분 및 잡어의 생산과 공급은 해마다 어족 자원의 고갈로 감소되고 있다. 이런 가운데 양식어종의 사료로 어분이나 잡어를 대체할 수 있는 단백질 공급원을 개발하고 활용하는 연구가 활발히 진행되고 있다. 역사적으로 대두는 약 5000년 전 중국에서 재배되기 시작했다. 사람들은 본격적으로 19세기 초부터 대두에 대한 연구를 시작하여 대두가 사람에게 중요한 단백질과 기름을 제공할 수 있다는 것을 깨달았다. 1950년대 초반에 이르러 대두박이 값싸지만 단백질이 풍부한 사료원료로서의 가치가 입증되면서, 축산업이 오늘의 전성기를 구가할 수 있는 계기가 마련되었다. 그렇지만 바다에서 식량을 생산하는데 있어서도 육지에서 가장 많이 재배되는 두류작물인 대두와 대두제품을 활용하기 시작한 것은 먼 오래전의 일이 아니다. 우리나라뿐만 아니라 세계 여러 나라에서도 담수어종인 잉어, 뱀장어 및 틸라피아등에서 대두박의 영양학적 우수성이나 경제성이 이미 입증된 바 있다. 앞으로 해산어 양식기술의 발달은 해산어용 전문 배합사료의 개발과 보급 없이는 불가능하기 때문에, 미국, 일본, 노르웨이등 해산어 양식 선진국들일수록 이 부문에 대한 연구 개발 노력이 특히 활발하다. 식생활은 물론이고 심지어는 친환경적 산업 제품에 이르기까지 대두와 대두제품이 우리의 각광을 받고 있는 것은 결코 콩이 지닌 물리적 성상, 영양학적 및 경제적 가치의 우수성 때문만은 아니다. 미국은 자국의 대두 생산자들이 생산해 낸 대두를 판매하면서 조성한 자조금을 모아 대두의 생산성을 향상시키기 위한 연구 개발과 국내외 시장을 확대하기 위한 마케팅 활동에 쓰고 있다. 이런 자조 노력은 비단 미국의 대두 농민들에게만 국한된 것이 아니다. 가깝게는 일본의 수산업과 해산어 양식산업의 발전은 중앙 및 지방 정부, 수협과 같은 어민 조합 및 연근해 수산업 종사자들이 출연한 기금을 통해 이루어지고 있음을 지난 8월 북해도의 양식산업을 시찰했을 때 확인할 수 있었던 사실이다. 이제 우리나라도 국민소득 1만불 시대를 넘어 2만불 시대를 열기 위한 청사진을 그릴 만큼 모든 경제의 규모가 확대되었을 뿐 아니라 질적으로 고도화되었다. 우리에게 필요한 것은 성숙된 산업사회에 걸맞는 각 산업 주체들의 의식이다. 한국의 양식산업도 자조 정신을 갖추어 생산성 향상에 초점을 맞춘 양식기술의 개발, 환경 보전을 고려한 양식장 관리 및 소비를 확대하기 위한 유통시스템의 선진화에 스스로 투자를 해야 할 시기에 와 있다.

• Korean Journal of Ecology and Environment
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• v.34 no.3 s.95
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• pp.251-258
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• 2001

The ichthyofauna and passing efficiency of fish ways were surveyed in the lower and upper regions of the river mouth dam in the lower reaches of the Nakdong river from June to December in 20()0. As the dam built in the river mouth, the brackish area in the estuary disappeared completely and the transitional area did not formed. The fishes collected from survey were classified into 49 species, 45 genera belonging to 29 families. Among them, the fresh water fishes composed of 10 species, peripheral freshwater fishes 11 species and sea water fishes 28 species respectively. Because of the ecological difference between the fresh and sea water, dominant species in the Myeong-ji of sea water area was Acanthogobius flavimanus (39.1%) and in the Sa-sang of fresh water area was Achanthorhodeus macropterus (44.4%). By the video camera records, fishes were identified nine species like as Coilia ectenes, Cyprinus carpio, Hemibarbus labeo, Squalidus gracilis majimae, Plecoglosus altivelis, Lateolabrax japonicus, Anguilla japonica, Mugil cephalus and Pholis nebulosa. Based on total species collected, the efficiency of the fish way for the anadromous fish was 10.1%. Therefore, efficiency evaluation of the fish way in the Nakdong River Mouth Dam was low.

• Journal of the Korean GEO-environmental Society
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• v.17 no.9
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• pp.37-45
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• 2016

This study analyzes the environmental and durability problems of traditional (LW) grouting method. And the proposed method was compared to the others effects by analyzing the in-situ applicability and effect of performance of the method using the silica sol. This study analyzed the eco-friendly, effects of high strength silica sol through laboratory tests. The effects of the construction process were identified through the field tests. The compressive strength was increased by 1.3 times compared to the LW method and the shrinkage is 3~8 times less than that of LW method with water glass. No toxicity, which could affect soil contamination. In particular, it was confirmed that the Toxicity fish also survived with little pH change in the concentration tank. Also it confirmed the construction effects through field test. Field tests are a standard penetration test, permeability test, LLT, BST. Permeability was reduced to $1{\times}10^{-5{\sim}-6}cm/sec$.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.17-18
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• 2018

19세기 이전부터 유럽에서는 해양치유자원을 이용한 치유요법인 탈라소테라피(Thalassotherapy)가 국민들의 건강을 지켜오고 있다. 탈라소테라피(Thalassotherapy)란 바다를 뜻하는 그리스어 'Thalassa'와 치료를 뜻하는 'Therapy'가 합쳐진 말로 해양치유자원을 이용해 신체적 정신적 건강을 증진시키는 활동을 뜻한다. 최근 우리나라에도 건강한 삶을 추구하는 인식의 변화 속에 다양한 해양치유자원을 이용하는 해양치유의 수요가 증가하고 있다. 본 논문에서는 해양치유산업의 활성화를 위한 해양치유자원의 현황 및 활용방안에 대해 연구하였다. 우리나라 해양치유자원의 분포를 확인하기 위해 동해, 서해, 남해, 제주도 등 4개의 권역으로 구분하여 전국을 대상으로 총괄도를 제작하였으며 국내외 해양치유자원을 이용해 작성된 문헌을 통해 해양치유자원의 이용현황에 대해 조사하였다. 또한 해양치유산업 선진국인 독일, 프랑스, 일본을 모델로 우리나라에 맞는 해양치유자원 적합기준을 연구하였다. 그 결과, 각 지역별 해양치유자원은 경기도:(머드, 염생식물, 염지하수, 해조류), 충청남도:(머드, 해조류, 천일염, 해조류), 전라북도:(머드, 염생식물, 해조류 해풍), 전라남도:(해조류, 해수, 천일염, 머드 해풍), 제주도:(용암해수, 염지하수, 태양광, 해수욕장), 강원도:(심층수, 태양광, 해조류, 해송림), 경상남도:(해조류, 해수욕장, 태양광, 해풍), 경상북도:(해조류, 태양광, 심층수, 염지하수, 해송림), 울산:(해조류, 태양광), 부산 :(해조류, 해수욕장, 태양광)이 있었으며 해양치유 자원을 이용해 작성된 국내외 논문은 265편(해수:101편, 머드:27편, 소금:12편, 해양환경:39편, 해양생물:18편, 해조류:68편)이 있었다. 해양치유자원 적합기준은 각 나라별 해양치유자원의 이용기준을 활용하여 자원별로 제시하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.4
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• pp.431-437
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• 1996

The efforts of removing the specific fresh water fishy odor were studied by inducing tilapia, Oreochromis niloticus, to sea water in the use of the flavoring chemicals such as pyrrolidine and piperidine as experimental flavors. The amines added to the grinded muscle of tilapia were recovered by $88\%$ for pyrrolidine and $90\%$ for piperidine. When live tilapia were retained in a tank containing 100 ppm solution of the flavor for 30 min and then begun to start the acclimation into sea water with daily increase of $5\%_{\circ}$ salinity within 7days, no amines in the skin and the muscle of tilapia were detected after 4 days of acclimation to sea water. For the purge effects of amino in the skin and the muscle of tilapia, the concentration of pyrrolidine and piperidine lost $73.4\%,\;83.7\%$ in the muscle and $93.6\%,\;90.6\%$ in the skin of tilapia after purging in fresh water for 72 hrs, while $66.2\%,\;73.6\%$ of amines were removed in the muscle and $90.1\%,\;87.7\%$ in the skin of tilapia acclimated to sea water after purging in on sea water for 72hr. Loss rates of pyrrolidine and piperidine were found to be $0.0231h-^{1}\;and\;0.0333\;h^{-1}$ from the muscle and $0.0652h-^{1}\;0.0413\;h^{-1}$from the skin of tilapia in the fresh water, while $0.0131h-^{1}\;and\;0.0354\;h^{-1}$ from the muscle, $0.0674h-^{1}\;and\;0.0549\;h^{-1}$ from the skin of tilapia in the sea water after 24hrs of exposure, respectively.