• Title/Summary/Keyword: Luring effect

Search Result 12, Processing Time 0.016 seconds

A Study on the Luring of fish Shoals into the Fyke net by the Underwater Sound Emission (제주도 연안의 각망어업에 있어서 수중음악에 의한 어군의 유집에 관한 연구)

  • Abn, Jang-Yong;Seo, Du-Ok;Kim, Sam-Kon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.32 no.1
    • /
    • pp.50-58
    • /
    • 1996
  • The authors carried out a field experiment to confirm the effect of underwater sound on the luring of fish schools in a setnet in the coast of Cheju Island. The effects of the acoustic emission on the luring of fish schools were observed using a manufectured underwater speaker in the setnet, and pure sound, of which frequency was 600Hz and the source level was 126dB, was emitted on and off at 5 minutes intervals in the set net during the night of ,July 29 and ,July 31. So we had recorded behavior of fish schools by the telesounder with two channel and shape of the setnet by underwater video camera and analyzed them. When the flood and ebb currents were around the setnet, the nets rised to the surface of water and it happened occasionaly at the stand of tide. Therefore, it was in the state that fish schools feel constraint to enter into the setnet, and was required a new design of the setnet stand up to strong tidal current. As the pure sound, of which frequency was 600Hz was emitted for the luring of fish schools in a setnet, the catch ammounts of fish, the young horce mackereWI'rachllrlls japonicus), was increased 4~6 times than not emitted.

  • PDF

The luring effect of the sardine bait for octopus pot in laboratory (실험실에서 문어 통발용 정어리 미끼의 유인 효과)

  • AN, Young-il
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.55 no.3
    • /
    • pp.190-197
    • /
    • 2019
  • This study investigated the luring effect of the sardine bait, which is used to catch octopus with pot, as the preliminary study for the development of alternative bait for octopus pot. The soaking time for bait was divided into "5 days or less" and "11 days or longer" The number of times octopus entered the pot with bait and the empty pot was investigated under dark adaptation and light adaptation processes and the distribution of tank section was investigated under light adaptation process. The case of "11 days or longer" sardine soaking time showed higher rate of distribution in the section of pot with bait compared to the case of "5 days or less" In the case of "5 days or less" soaking time, the number of times the octopus entered the pot with bait was similar to that it entered the pot without it even during dark adaptation and light adaptation. However, in the case of "11 days or longer", the octopus entered the pot with bait more quickly than the pot without bait and more frequently during dark adaptation hours. There were cases where the octopus did not enter any pot. In the case of "5 days or less", with less decomposition of baits, the octopus entered the empty pot more during light adaptation process, and it appeared that the pot was used as a hideout.

A Thronging Response of the Shoal of Rudder Fish , Seriola Dumerili ( Risso ) to Audible Underwater Sound (수중 가청음에 대한 잿방어 어군의 유집 반응)

  • 이창헌
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.33 no.4
    • /
    • pp.285-289
    • /
    • 1997
  • A Held experiment was carried out to confirm the effect of underwater sound on the luring of fish school of rudder fish in a set net at the coast of Cheju Island. The effects of the acoustic emission on the luring of fish school were observed at a cage around a set net fishing ground using a manufactured underwater speaker. Underwater sounds that were emitted for the luring of fish school were the pure sounds of which frequency were 300Hz and 400Hz, engine noise and swimming sound. The results of the observation are as follows : 1. The input and output wave forms of a manufactured underwater speaker in water tank were similar to those in measurement frequencies. The result of the observation indicated that it could be used for the purpose of the sound emission in measurement frequencies. 2. The effect of the emitted pure sound of 300Hz, 400Hz was remarkable for the luring of fish school in 2 minutes after the sound emission. The reaction of fish school was more sensitive to the pure sound of 400Hz than 300Hz. 3. The effect of the emitted engine noise was more remarkable than that of the pure sound for 3 minute continuously. On the feeding sound, fish formed a shoal and swimmed, but didn't gather around the underwater speaker. 4. The feeding and swimming sound spectra on rudder Hsh showed similar sound pressure distribution each other, they appeared low sound pressure in frequencies of 200-600Hz.

  • PDF

A basic study on the development of alternative bait for octopus pots (문어 통발용 대체 미끼 개발을 위한 기초연구)

  • AN, Young-il
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.56 no.3
    • /
    • pp.202-212
    • /
    • 2020
  • In order to replace sardine baits for octopus pot, an efficacy experiment to lure with alternative bait (fermented skate or chicken skin in artificial crab or northern clam) pots and sardine pot were conducted in a circular water tank. The soaking time of the sardine bait was divided into two categories: six days or less and seven days or more. The behavioral response of octopus to the artificial bait pots and sardine pot were investigated. In the comparison of the luring effects between pots with fermented skate inside artificial crab or northern clam and sardine pot, the pot with artificial crab + fermented skate had better results than the other pots in the section distribution (31.6%) and the number of times the pot was entered into (20.0%) (p > 0.05). In the comparison of the luring effects between pots with chicken skin inside artificial crab or northern clam and sardine pot, the pot with northern clam + chicken skin had better results than the other pots in the section distribution (22.6%) and number of times the pot was entered into (55.6%) (p < 0.05). The results were also better compared to those of pot with artificial crab + fermented skate. From these results, it seems that in the luring effect aspect, sardine bait can be replaced with artificial bait consisting of chicken skin inside northern clam.

Effects an Acoustical Equipment on the Luring of Fish School (음향집어기의 집어 효과)

  • 장선덕
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.22 no.4
    • /
    • pp.75-82
    • /
    • 1986
  • A field experiment was carried out to clarify the effect of underwater sound on the luring of fish school. The effects of. the acoustic emission on the luring of fish school were checked actually at a set net fishing site in Namhae using a commercial acoustic equipment, Dairyo-8. An emitting system of sound was designed by the authors, and the ambient noise, the sound pressure level and the reaction of fish school were measured in the set net. 1. The predominent frequency band of ambient noise was 150Hz-400Hz,.and the sound emitted was 400Hz-100Hz. The sound pressure level of ambient noise in set net was higher at the landing part, and lower at the playgrond, the gate of court and "the enterance of inclined "passage. The ambient noise was increased with the time elapse-d at the stage of hauling net, but :it was decreased suddenly at the final stage due probably to the decrease of the swimming speed of the fish school. 2. The results of the observation and the recording paper of echo sounder indicate that the effect of emitting sound in the bag net of set net was remarkable for the luring of fish school in the early stage, but decreased after 30 minutes. The reaction of fish school is more sensitiv2 to the sound pressure level than the time intervals between the emission and the pause. For the purpos~ of practical use, it is nesessary to confirm what kind of sound pressure level is the best for the luring of fish school. 3. In response to the acoustic equipment(Dairyo-8), fish school started to swarm 20 minutes after the sound emission and scattered when the sound paused. As the emitting pattern of the acoustic equiment, the three seconds of emission after one second of pause was more effective than the continuous emission at the set net fishing ground. Catch of the fish(s during th~ sound ernissio:l at the gate of court was three to five times more than that of no emission.

  • PDF

A Response of the Shoal of Chub Mackerel ( Scomber Japonics , HOVTTYUN ) to Underwater Sound (수중음에 대한 고등어 어군의 반응)

  • 서두옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.25 no.1
    • /
    • pp.12-17
    • /
    • 1989
  • A field experiment was carried out of confirm the effect of underwater sound on the luring of fish school of chub mackerel in the coast of Idousyo Island. Underwater sound that was made use of luring of fish school was pure sound and interval pure sound which the frequencies of the sound were 150Hz and 200Hz, respectively. The results of the observation of hooking and recording paper of fish finder indicate that the effect of emitting sound at 20m in the depth of water was remarkable for the luring of fish school of chub mackerel. The vertical pure sound pressure level at 150Hz and 200Hz of the water layer that was lured the fish school of chub mackerel were 140.1dB and 146.dB at 30m, 121.0dB and 126.6dB at 70m and 141.9dB and 120.5dB at 120m in the depth of water, respectively.

  • PDF

Effect of cyclic Change of Wet Bulb Temperature During Yellowing Stage on Chemical Properties of Flue-Cured Tobacco (황색종 cyclic 건조엽의 화학성분 특성)

  • Lee, Chul-Hwan;Jin, Jeong-Eui;Han, Chul-Soo
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.20 no.1
    • /
    • pp.19-25
    • /
    • 1998
  • The bulk curing experiment to the improve the quality of flue-cured leaves were carried out to evaluate relationship between cyclic curing and conventional curing method. We studied the effect of the cyclic change of wet bulb temperature at the yellowing stage of flue curing on chemical properties of cured leaves. The wet bulb temperature was automatically controlled between preset high($38^{\circ}C$) and low point ($35^{\circ}C$) everyone hour cyclically during 12 hours after starting luring. As a result, the acceleration of the increase in the chemical properties of cured leaves were observed. As to the chemical properties, there was decreased in citric acid, increased in malic acid of the nonvolatile organic acids and all higher fatty acids content of leaves cured by this method compared with in that of conventional curing method, while a major chemical compounds in relation to aromatic essence of cigarette smoke in essential oil components of lured leaves was mostly higher in this method than those of conventional ones, and it was evaluated that there was decreased in CO, TPM, Tar, and $CO_2$ content of the cigarette smoke comparing to the conventional luring method.

  • PDF

Effect of Complete Fasting on Body Fatness, Serum Leptin and Lipid Profile in Women (여성에서 절식이 체지방과 혈청의 Leptin 및 지질조성에 미치는 영향)

  • 이은옥;박현서;신현대
    • Journal of Nutrition and Health
    • /
    • v.33 no.1
    • /
    • pp.42-48
    • /
    • 2000
  • The study was designed to observe the effect of complete listing for 10 days on body fatness, serum leptin level and lipid profile in thirty women who were admitted to fasting Clinical Program in Kyung-Hee Oriental Medical Center. Most of the subjects had food habits of over-eating and preferred oily foods which was correlated to the increase of body weight and BMI during realimentation. Average loss of body weight was 7.98kg and waist-hip ratio was significantly decreased during fasting. Body weight showed significant positive correlation with body fat(r=0.8182), lean body mass(r=0.7797) and total body water(r=0.7563). Body fat was gradually reduced after 9 days fasting, but lean body mass was not diminished any more after 7 days luring. Serum leptin level was significantly decreased after luring and re-feeding. The leptin showed significant positive correlation with body weight(r=0.9324), body mass index(r=0.8279) and body fat(r=0.8376). The levels of serum total cholesterol and LDL-C were significantly increased but HDL-C level was significantly decreased after fasting which increased could be harmful for persons with hypercholesterolemia. VLDL-C and triglyceride levels were not significantly decreased after fasting. Serum total free fatty acid level was significantly increased after fasting. These data suggest that the best way of maintaining the reduced body weight was to carry out the modification of food habits and behavior in daily lift. It could not be recommended to repeat often complete luting for reduction of body weight. (Korean J Nutrition 33(1) : 42-48, 2000)

  • PDF

Hydro-acoustic survey on fish distribution and aggregated fish at artificial reefs in marine ranching area (음향조사기법을 이용한 수산자원 관리수면의 어류분포 및 인공어초지역의 어군위집조사)

  • Kim, Hyun-Young;Hwang, Bo-Kyu;Lee, Yoo-Won;Shin, Hyeon-Ok;Kwon, Jung-No;Lee, Kyung-Hoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.47 no.2
    • /
    • pp.139-145
    • /
    • 2011
  • Hydro-acoustic survey was carried out to estimate a fish distribution at marine ranching area and aggregated fish schools at artificial reef area in Oeyeondo, Korea. The survey system was set up with DGPS system, scientific echo sounder (EK60, Simrad Co.), and ECDIS (Mecys. Co. LTD). A track survey and a random survey was respectively applied to the marine ranching area (474.4ha) and to the artificial reef area (within a radius of 300m). As the result, fish distribution and MVBS values in marine ranching area showed that created fisheries resources didn't come to be abundant yet as to appear fish distribution in all of the area. In the artificial reef area, it was, however, able to detect many fish school signals on the top of and around artificial reefs and to confirm the luring effect of artificial reefs.

Analysis on Effectiveness for HOV lane using Intergration Simulation (Intergration 시뮬레이션을 이용한 HOV전용차로 효과 분석)

  • Hong Sung-ho;Kim Jin-woo;Ki Yong-kul
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2005.11a
    • /
    • pp.125-129
    • /
    • 2005
  • As metropolitan areas are rapidly growing in both population and physical size, so too has the problem of traffic congestion. Magnifying this is the limited financial resources and lack of road corridor space available to juggle the many competing demands. High Occupancy Vehicle (HOV) facilities have been implemented in an attempt to alleviate the problem of growing congestion while considering the issue of limited funding and lack of physical space. HOV lanes may increase the efficiency of a road corridor by maximising its person carrying capacity. These facilities are meant to provide priority treatment to HOVs, thereby luring people to choose a transport mode with a higher occupancy than the single occupant vehicle (SOV), such as buses or carpools. This paper analyze the issues surrounding HOV lanes, their effect, problems and their evaluation by using Intergration, that is Traffic Simulation Software, when HOV lanes be implemented in the Olympic Highway.

  • PDF