Pub Date : 2009-11-30DOI: 10.3796/KSFT.2009.45.4.201
Bong-Seong Bae, Heui–Chun An, Seong-wook Park, Hae-Hoon Park, Y. Chun
Cast fishing gear needs some time for fishing progress, and catches and their composition by submerged timecan change by several cause. Therefore, it is very importance to study fishing capacity of fishing gear bysubmerged time. This study is to investigate catches and their composition of shrimp trap, that is used in thecoastal of the East Sea, and to find the fittest lifting time of trap. Experimental term are September 2006 andAugust 2007, the location is the coastal of Oho, Goseong, Gangwondo, Korea and one hundred trap is used ateach casting and lifting of gear. For convenience of description, survey of 2006 and 2007 are denoted asexperimental code 1 and 2, and submerged time 21hr, 43hr and 66hr are denoted as code A, B and C. Theresult of obtained from the above approach are summarized as follows: Many Northern shrimps(
{"title":"Catch characteristics of shrimp trap by submerged time","authors":"Bong-Seong Bae, Heui–Chun An, Seong-wook Park, Hae-Hoon Park, Y. Chun","doi":"10.3796/KSFT.2009.45.4.201","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.4.201","url":null,"abstract":"Cast fishing gear needs some time for fishing progress, and catches and their composition by submerged timecan change by several cause. Therefore, it is very importance to study fishing capacity of fishing gear bysubmerged time. This study is to investigate catches and their composition of shrimp trap, that is used in thecoastal of the East Sea, and to find the fittest lifting time of trap. Experimental term are September 2006 andAugust 2007, the location is the coastal of Oho, Goseong, Gangwondo, Korea and one hundred trap is used ateach casting and lifting of gear. For convenience of description, survey of 2006 and 2007 are denoted asexperimental code 1 and 2, and submerged time 21hr, 43hr and 66hr are denoted as code A, B and C. Theresult of obtained from the above approach are summarized as follows: Many Northern shrimps(","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"391 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131459165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-11-30DOI: 10.3796/KSFT.2009.45.4.223
Bongjin Cha, S. Yoon, R. Jung, Soung-gill Kim, Jae-Soung Lee, Won-Duck Yoon, Jong-Keun Shin
It has been considered that fishing areas for shrimp beam trawl have been in ruin because Korean localgovernments have permitted trawling into the areas limited by the fisheries local regulations from 1994.Physical and biological effects of the trawling were investigated in the study. Physical effects wereinvestigated by optical methods such as trawling tracking by side scan sonar and comparing the gear bothbefore and after trawling. Biological aspects were investigated by grab sampling of benthic animals,concentration of trace metals in sediment and a flux evaluation of NH
{"title":"A primary study on the effect of artificial disturbance on a fishing area by shrimp beam trawl","authors":"Bongjin Cha, S. Yoon, R. Jung, Soung-gill Kim, Jae-Soung Lee, Won-Duck Yoon, Jong-Keun Shin","doi":"10.3796/KSFT.2009.45.4.223","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.4.223","url":null,"abstract":"It has been considered that fishing areas for shrimp beam trawl have been in ruin because Korean localgovernments have permitted trawling into the areas limited by the fisheries local regulations from 1994.Physical and biological effects of the trawling were investigated in the study. Physical effects wereinvestigated by optical methods such as trawling tracking by side scan sonar and comparing the gear bothbefore and after trawling. Biological aspects were investigated by grab sampling of benthic animals,concentration of trace metals in sediment and a flux evaluation of NH","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"211 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126141177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.165
Dae-jae Lee
The process of berthing/deberthing operations for entering/leaving vessels in Busan northern harbor wasanalyzed and evaluated by using an integrated VTS(vessel traffic service) system installed in the ship trainingcenter of Pukyong National University, Busan, Korea. The integrated VTS system used in this study wasconsisted of ARPA radar, ECDIS(electronic chart display and information system), backup(recording) system,CCTV(closed-circuit television) camera system, gyro-compass, differential GPS receiver, anemometer,AIS(automatic identification system), VHF(very high frequency) communication system, etc. The network ofthese systems was designed to communicate with each other automatically and to exchange the criticalinformation about the course, speed, position and intended routes of other traffic vessels in the navigationalchannel and Busan northern harbor. To evaluate quantitatively the overall dynamic situation such asmaneuvering motions for target vessel and its tugboats while in transit to and from the berth structure inside aharbor, all traffic information in Busan northern harbor was automatically acquired, displayed, evaluated andrecorded. The results obtained in this study suggest that the real-time tracking information of traffic vesselsacquired by using an integrated VTS system can be used as a useful reference data in evaluating and analyzingexactly the dynamic situation such as the collision between ship and berth structure, in the process ofberthing/deberthing operations for entering/leaving vessels in the confined waters and harbor.Key words : Berthing/deberthing operations, VTS system, Busan northern harbor, Real-time tracking
{"title":"Real-time monitoring of berthing/deberthing operations process for entering/leaving vessels using VTS system in Busan northern harbor, Korea","authors":"Dae-jae Lee","doi":"10.3796/KSFT.2009.45.3.165","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.165","url":null,"abstract":"The process of berthing/deberthing operations for entering/leaving vessels in Busan northern harbor wasanalyzed and evaluated by using an integrated VTS(vessel traffic service) system installed in the ship trainingcenter of Pukyong National University, Busan, Korea. The integrated VTS system used in this study wasconsisted of ARPA radar, ECDIS(electronic chart display and information system), backup(recording) system,CCTV(closed-circuit television) camera system, gyro-compass, differential GPS receiver, anemometer,AIS(automatic identification system), VHF(very high frequency) communication system, etc. The network ofthese systems was designed to communicate with each other automatically and to exchange the criticalinformation about the course, speed, position and intended routes of other traffic vessels in the navigationalchannel and Busan northern harbor. To evaluate quantitatively the overall dynamic situation such asmaneuvering motions for target vessel and its tugboats while in transit to and from the berth structure inside aharbor, all traffic information in Busan northern harbor was automatically acquired, displayed, evaluated andrecorded. The results obtained in this study suggest that the real-time tracking information of traffic vesselsacquired by using an integrated VTS system can be used as a useful reference data in evaluating and analyzingexactly the dynamic situation such as the collision between ship and berth structure, in the process ofberthing/deberthing operations for entering/leaving vessels in the confined waters and harbor.Key words : Berthing/deberthing operations, VTS system, Busan northern harbor, Real-time tracking","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"255 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133781269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.135
Young-il An, Hakgeun Jeong, B. Jung
, to different colors of LED light,individual distribution in the dark condition without LED light stimuli, individual distribution when four colorsof light stimuli were at the sections of end and middle of water tank and the changes of gathering rates as theelapse of illuminating time were examined. When it was dark, the distribution of the fish in each section of thetank was Ushape regardless of the investigating time intervals, which means that
{"title":"Behavioral reaction of common squid Todarodes pacificus to different colors of LED Light","authors":"Young-il An, Hakgeun Jeong, B. Jung","doi":"10.3796/KSFT.2009.45.3.135","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.135","url":null,"abstract":", to different colors of LED light,individual distribution in the dark condition without LED light stimuli, individual distribution when four colorsof light stimuli were at the sections of end and middle of water tank and the changes of gathering rates as theelapse of illuminating time were examined. When it was dark, the distribution of the fish in each section of thetank was Ushape regardless of the investigating time intervals, which means that","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116606087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.157
Kyounghoon Lee, J. Choi, Jong-Keun Shin, D. Chang, Seong-wook Park
), which was distributed in East Sea, was recently caught in Yellow Sea during asummer season from 2006. The fishery resources density research was carried out in Korea-ChinaProvisional Water Zone using trawl fishing gear and acoustics in National Fisheries Research &Development Institute in Korea. This paper showed the analysis on the acoustical backscattering strength bytwo frequencies(38kHz, 120kHz) for Japanese common squid by acoustical scattering theoretical modelbased on size distribution for survey period, and estimate the density distribution for squids integrated layerwhich was extracted from any scatterers distributed in water column using two frequency difference methodwhich has been used to distinguish fish shoals or specific target scatterers from sound scattering layer whichis composed of various zooplankton. Furthermore, the entire range of their density estimation was suggestedusing by Monte Carlo simulation under considering each uncertainty such as size distributions or swimmingangle and so on in survey area.Key words : Japanese common squid, Todarodes pacificus, Acoustical scattering theoretical model, DWBA,Density estimates
{"title":"Acoustical backscattering strength characteristics and density estimates of Japanese common squid distributed in Yellow Sea","authors":"Kyounghoon Lee, J. Choi, Jong-Keun Shin, D. Chang, Seong-wook Park","doi":"10.3796/KSFT.2009.45.3.157","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.157","url":null,"abstract":"), which was distributed in East Sea, was recently caught in Yellow Sea during asummer season from 2006. The fishery resources density research was carried out in Korea-ChinaProvisional Water Zone using trawl fishing gear and acoustics in National Fisheries Research &Development Institute in Korea. This paper showed the analysis on the acoustical backscattering strength bytwo frequencies(38kHz, 120kHz) for Japanese common squid by acoustical scattering theoretical modelbased on size distribution for survey period, and estimate the density distribution for squids integrated layerwhich was extracted from any scatterers distributed in water column using two frequency difference methodwhich has been used to distinguish fish shoals or specific target scatterers from sound scattering layer whichis composed of various zooplankton. Furthermore, the entire range of their density estimation was suggestedusing by Monte Carlo simulation under considering each uncertainty such as size distributions or swimmingangle and so on in survey area.Key words : Japanese common squid, Todarodes pacificus, Acoustical scattering theoretical model, DWBA,Density estimates","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131611956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.151
Heui–Chun An, Kyounghoon Lee, J. Bae, Bong-Seong Bae, Jong-Keun Shin
This study shows that the distribution density of snow crab, Chionoecetes opilio, was estimated using an underwater video monitoring system attached on the towing sledge. The field experiments were carried out at the coastal waters around Chuksan, East Sea, where ranged from 110 to 130m depth during September and October 2007. The sledge was towed for 40 minutes and the towing speed was controlled between 1.5 to 1.7 knot and each research areas were calculated to multiply towed distance by the detection width of the video monitoring system(1.2m), and then, distribution density of snow crab in each observations were estimated as a counted number of crab per 1,000. The result shows that their survey, taken between two months, reflected similar results during survey period, and the maximum and mean distribution densities in September estimated to be 77.0(number/1,000) and 19.9, respectively, and those of October were 36.0 and 21.8, respectively.
{"title":"Estimation of the distribution density of snow crab, Chionoecetes opilio using a deep-sea underwater camera system attached on a towing sledge","authors":"Heui–Chun An, Kyounghoon Lee, J. Bae, Bong-Seong Bae, Jong-Keun Shin","doi":"10.3796/KSFT.2009.45.3.151","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.151","url":null,"abstract":"This study shows that the distribution density of snow crab, Chionoecetes opilio, was estimated using an underwater video monitoring system attached on the towing sledge. The field experiments were carried out at the coastal waters around Chuksan, East Sea, where ranged from 110 to 130m depth during September and October 2007. The sledge was towed for 40 minutes and the towing speed was controlled between 1.5 to 1.7 knot and each research areas were calculated to multiply towed distance by the detection width of the video monitoring system(1.2m), and then, distribution density of snow crab in each observations were estimated as a counted number of crab per 1,000. The result shows that their survey, taken between two months, reflected similar results during survey period, and the maximum and mean distribution densities in September estimated to be 77.0(number/1,000) and 19.9, respectively, and those of October were 36.0 and 21.8, respectively.","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127431165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.144
Young-il An
The choice behavior of the octopus in response to the environment-friendly colored sinker for octopus drift-line and the sinkers fishing effect were studied under experimental conditions in the water tank and thefield. The colors of the sinkers used for the experiment are white, black, yellow and green. Artificial baitsare attached to the sinkers in order to attract the octopuses in the experiment. In the water tank experiment,two sinkers of two different colors are placed in a compartmentalized corner of the rectangular tank, and aCCD camera records the choice behaviors of the octopuses to the colored sinkers. In the field experiment,the catch investigation of octopus for each colored sinker was conducted 14 times in total by using 2(A, B)commercial fishing boats at the coast of Gangneung within 30m of depth in 2006. The number of coloredsinkers per operation was a total of 24-40 pieces with the same number of sinkers individually for fourcolors. As a result, it was found that the octopus selected white the most followed by black and yellow intheir choice of colored sinkers in the water tank experiment, and green was the lowest in their choice. Evenin the field experiment, the sinkers of white and black showed a higher catch of octopus than the sinkers ofyellow and green. Key words : Octopus Drift-line, Environment-friendly Sinker, Color effect
{"title":"Color effect of the environment-friendly sinker for octopus drift-line","authors":"Young-il An","doi":"10.3796/KSFT.2009.45.3.144","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.144","url":null,"abstract":"The choice behavior of the octopus in response to the environment-friendly colored sinker for octopus drift-line and the sinkers fishing effect were studied under experimental conditions in the water tank and thefield. The colors of the sinkers used for the experiment are white, black, yellow and green. Artificial baitsare attached to the sinkers in order to attract the octopuses in the experiment. In the water tank experiment,two sinkers of two different colors are placed in a compartmentalized corner of the rectangular tank, and aCCD camera records the choice behaviors of the octopuses to the colored sinkers. In the field experiment,the catch investigation of octopus for each colored sinker was conducted 14 times in total by using 2(A, B)commercial fishing boats at the coast of Gangneung within 30m of depth in 2006. The number of coloredsinkers per operation was a total of 24-40 pieces with the same number of sinkers individually for fourcolors. As a result, it was found that the octopus selected white the most followed by black and yellow intheir choice of colored sinkers in the water tank experiment, and green was the lowest in their choice. Evenin the field experiment, the sinkers of white and black showed a higher catch of octopus than the sinkers ofyellow and green. Key words : Octopus Drift-line, Environment-friendly Sinker, Color effect","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115862002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-08-31DOI: 10.3796/KSFT.2009.45.3.177
Dae-jae Lee
This paper describes a automatic video surveillance system(AVSS) with long range and 360 coverage that is automatically rotated in an elevation over azimuth mode in response to the TTM(tracked target message) signal of vessels tracked by ARPA(automatic radar plotting aids) radar. This AVSS that is a video security and tracking system supported by ARPA radar, CCTV(closed-circuit television) camera system and other sensors to automatically identify and track, detect the potential dangerous situations such as collision accidents at sea and berthing/deberthing accidents in harbor, can be used in monitoring the illegal fishing vessels in inshore and offshore fishing ground, and in more improving the security and safety of domestic fishing vessels in EEZ(exclusive economic zone) area. The movement of the target vessel chosen by the ARPA radar operator in the AVSS can be automatically tracked by a CCTV camera system interfaced to the ECDIS(electronic chart display and information system) with the special functions such as graphic presentation of CCTV image, camera position, camera azimuth and angle of view on the ENC, automatic and manual controls of pan and tilt angles for CCTV system, and the capability that can replay and record continuously all information of a selected target. The test results showed that the AVSS developed experimentally in this study can be used as an extra navigation aid for the operator on the bridge under the confusing traffic situations, to improve the detection efficiency of small targets in sea clutter, to enhance greatly an operator s ability to identify visually vessels tracked by ARPA radar and to provide a recorded history for reference or evidentiary purposes in EEZ area.
{"title":"Automatic identification of ARPA radar tracking vessels by CCTV camera system","authors":"Dae-jae Lee","doi":"10.3796/KSFT.2009.45.3.177","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.3.177","url":null,"abstract":"This paper describes a automatic video surveillance system(AVSS) with long range and 360 coverage that is automatically rotated in an elevation over azimuth mode in response to the TTM(tracked target message) signal of vessels tracked by ARPA(automatic radar plotting aids) radar. This AVSS that is a video security and tracking system supported by ARPA radar, CCTV(closed-circuit television) camera system and other sensors to automatically identify and track, detect the potential dangerous situations such as collision accidents at sea and berthing/deberthing accidents in harbor, can be used in monitoring the illegal fishing vessels in inshore and offshore fishing ground, and in more improving the security and safety of domestic fishing vessels in EEZ(exclusive economic zone) area. The movement of the target vessel chosen by the ARPA radar operator in the AVSS can be automatically tracked by a CCTV camera system interfaced to the ECDIS(electronic chart display and information system) with the special functions such as graphic presentation of CCTV image, camera position, camera azimuth and angle of view on the ENC, automatic and manual controls of pan and tilt angles for CCTV system, and the capability that can replay and record continuously all information of a selected target. The test results showed that the AVSS developed experimentally in this study can be used as an extra navigation aid for the operator on the bridge under the confusing traffic situations, to improve the detection efficiency of small targets in sea clutter, to enhance greatly an operator s ability to identify visually vessels tracked by ARPA radar and to provide a recorded history for reference or evidentiary purposes in EEZ area.","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"308 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121293829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-05-31DOI: 10.3796/KSFT.2009.45.2.077
Byung-Yeob Kim, Young-Seok Park, Chang-Heon Lee
This paper is to investigate the effect of the immersion time in the traditional hairtail hand line fordeveloping the fishing methods and the fishing gear in the coast of jeju. The operating of 32 times was madewith each different immersion time of hairtail hand line, and the relations between the catch and theimmersion time were examined. As the result, targeted species rate was over 98% of total catch. From about800 seconds after casting, the hooking rate was decreased and the bite loss rate was increased, it seems to bemade by the decreasing factors of predators including the cutting of branch lines etc. In addition, it wassupposed that the hooking rate and the bait loss rate had a deep connection with feeding time zone. The levelof the correlation coefficient of the bait loss rate according to the immersion time was 0.54 at p 0.01, in thecase of the hooking rate, 0.59 was chosen after about 800 seconds. The hooking rate and the bait loss rateaccording to the hook number were not irrelevant to the fish school layer. Additionally, it was assumed thatthe bait loss rate was related to the depth of water.Key words : Hairtail hand line, Hooking rate, Bait loss rate, Immersion time
{"title":"Hooking rate and bait loss rate of traditional hairtail hand line according to immersion time in the coastal waters of Jeju","authors":"Byung-Yeob Kim, Young-Seok Park, Chang-Heon Lee","doi":"10.3796/KSFT.2009.45.2.077","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.2.077","url":null,"abstract":"This paper is to investigate the effect of the immersion time in the traditional hairtail hand line fordeveloping the fishing methods and the fishing gear in the coast of jeju. The operating of 32 times was madewith each different immersion time of hairtail hand line, and the relations between the catch and theimmersion time were examined. As the result, targeted species rate was over 98% of total catch. From about800 seconds after casting, the hooking rate was decreased and the bite loss rate was increased, it seems to bemade by the decreasing factors of predators including the cutting of branch lines etc. In addition, it wassupposed that the hooking rate and the bait loss rate had a deep connection with feeding time zone. The levelof the correlation coefficient of the bait loss rate according to the immersion time was 0.54 at p 0.01, in thecase of the hooking rate, 0.59 was chosen after about 800 seconds. The hooking rate and the bait loss rateaccording to the hook number were not irrelevant to the fish school layer. Additionally, it was assumed thatthe bait loss rate was related to the depth of water.Key words : Hairtail hand line, Hooking rate, Bait loss rate, Immersion time","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126279862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-05-31DOI: 10.3796/KSFT.2009.45.2.114
Suk-Ho Jung
There are increased in using the bio-ethanol, as the carbon neutral attracts many researchers due to a reduction in carbon dioxide spotted as the global warming gas. A gasoline engine with 100% of the bio- ethanol was developed and used in Brazil already, but researches of using the bio-ethanol in diesel engines are lack. In this study, combustion tests with blend fuel of the gas oil and bio ethanol by 50% maximally due to a low cetane number of bio-ethanol were accomplished as a basic study of introduction of using the bio- ethanol in diesel engines. The result was that smoke emission was decreased with increase in proportion of the bio-ethanol, due to the increase of a amount of pre-mixed combustion with ignition delay. Although the amount of CO2 is reduced according as the bio-ethanol is used(carbon neutral), the emission of CO2 with increase in the proportion of the bio-ethanol was more increased due to lower a heat value of bio-ethanol than gas oil.
{"title":"Combustion characteristics of diesel engine with bio-ethanol blend fuel","authors":"Suk-Ho Jung","doi":"10.3796/KSFT.2009.45.2.114","DOIUrl":"https://doi.org/10.3796/KSFT.2009.45.2.114","url":null,"abstract":"There are increased in using the bio-ethanol, as the carbon neutral attracts many researchers due to a reduction in carbon dioxide spotted as the global warming gas. A gasoline engine with 100% of the bio- ethanol was developed and used in Brazil already, but researches of using the bio-ethanol in diesel engines are lack. In this study, combustion tests with blend fuel of the gas oil and bio ethanol by 50% maximally due to a low cetane number of bio-ethanol were accomplished as a basic study of introduction of using the bio- ethanol in diesel engines. The result was that smoke emission was decreased with increase in proportion of the bio-ethanol, due to the increase of a amount of pre-mixed combustion with ignition delay. Although the amount of CO2 is reduced according as the bio-ethanol is used(carbon neutral), the emission of CO2 with increase in the proportion of the bio-ethanol was more increased due to lower a heat value of bio-ethanol than gas oil.","PeriodicalId":211073,"journal":{"name":"Bulletin of The Korean Society of Fisheries Technology","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116052905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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