• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.312-316
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• 1982

With an object to obtain an indication on the efficiency of the saury baits for tuna longline, frequencies of the saury heads found in the tuna stomachs were analysed by the equations developed from tile binomial distribution. Four factors were introduced into the equations : The hooking rate, p; rate of not being hooked q; rate of the effective baits retained in the stomachs of the captured tuna r; and the rate of tile previously taken baits retained in the tuna stomachs, t. The best estimates of $\frac{p}{p+q^t}$ and r are empirically obtained as follows. Yellowfin tuna: $\frac{p}{p+q^t}$=0.789, r=0.598 Bigeye tuna: $\frac{p}{p+q^t}$=0.810 r=0.608, Albacore tun : $\frac{p}{p+q^t}$=0.838, r=0.621.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.194-215
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• 2021

Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.441-447
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• 2015

As a series of research plan, this study is to provide basic data necessary for the development of fishing industry which will contribute in establishing sound fishing culture in Jeju island through systematic management of fishing, protection of fishery resources and establishment of safety measures for fishermen in accordance with 'Fishing Management and Support Act'. To attain the proposed objective, this study conducted literature review and surveys on restriction standards of harmful substances generated from fishing equipment and baits, examined the current status of fishing management in popular fishing sites of other cities, and then reviewed and analyzed the fishing management and fishing-restriction zones in Jeju island. The survey on the opinions on the restriction criteria of fishing methods, tools and period, including the acceptable standards for harmful substances showed that general fishermen preferred 'alleviating the measure (44.8%)' to 'aggravating the measure (23.0%)'. Meanwhile, maritime police showed dominant opinion toward 'aggravating the restriction (52.2%)' over 'alleviating the measure (4.3%)'. Furthermore, fishing-related enterprise is favored 'aggravating the restriction (32.6%)' over 'alleviating the measure (27.9%)'. In the survey on the tolerance of fishing baits including criterion for content of certain substance in different types of bait, it showed 57.5% of general fishermen preferred alleviating restriction criteria while 20.7% of them favored tougher restriction. Whereas, 33.3% of maritime police group insisted such fishing baits should be more restricted while 16.7% answered it should be alleviated. 35.9% of fishing-related enterprise was in favor of alleviation while 14.3% preferred aggravation. Upon investigation on the status of fishing management in other cities and towns, it turned out that most of them had safety and convenience facilities, installed warning and guide signs in fishing sites, and set no fishing zones. The review of fishing management and restricted area showed that 10 sites required access restriction and 2 of 10 sites were considered to be partially restricted for weather and season. 82 fishing sites were regarded as unnecessary to be restricted and installation of safety facility and guide signs is necessary for the safety of fishermen.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.301-309
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• 2007

In order to develop the artificial bait of trap for swimming crabs, the attracting effect was analyzed in the duration time of attracting effect, preference and shape recognition to the bait in the water tank and field experiments. According to the result which investigated the mean entrapped number of swimming crabs into the trap for each bait(mackerel, sardine and anchovy) in water tank experiments, the mean entrapped number was found to be higher in the trap with mackerel(6.9 ind.; 23.0%) than in other traps with sardine(5.2 ind.; 17.3%) and anchovy(3.4 ind.; 11.3%). In addition, the mean entrapped ratios of swimming crabs into the traps for 3 kinds of baits were estimated to be over 80% all in 5 hours after soaked in the water tank. For preference of swimming crabs to 3 kinds of baits, the trap with mackerel(6.9 ind.; 23.0%) was evaluated to be higher than the traps with sardine(2.8 ind.; 9.3%) and anchovy(0.2 ind.; 0.7%). In the field experiments, the mean entrapped number of swimming crabs into the trap with mackerel and sardine were found to be similar as 120 and 118 ind., but the trap with anchovy was only 85 ind.. According to the result which investigated the shape regnition of swimming crabs to the bait used mackerel, divided into 8 pieces, 16 pieces and grinded mass in water tank experiments, the mean entrapped number of swimming crabs into the traps that includes the mackerel divided into several pieces was significantly decreased. Moreover, by the presence of skin of mackerel for bait, there was a great difference in the entrapped number of swimming crabs. Therefore, it was thought that the swimming crab was attracted to the bait and entrapped into the trap would indicate that not only the chemical stimuli such as the attactant, but also the visual stimuli such as the shape recognition to the bait might be closely related.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.2
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• pp.96-103
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• 2009

The biodegradability in water of the artificial baits for blue crab pots which were made of intestines of mackerel, tuna and grinded krill were studied. The biodegradability of artificial bait was evaluated with the effective capacity of 10L water tank which was made of acryl pipe at the velocity of 1m/d and hydraulic retention time of 12 hours. For the 23 days operation time, all artificial baits were degraded fast at the early stage of operation time and stabilized within 5 days after start up. The rates of biodegradation were different depending on the raw materials of artificial baits. In terms of degradation rate of organic matter which can be expressed as COD, artificial bait made of tunas intestine showed the fastest degradation rate. On the other hand, in terms of degradation rate of nitrogenous matter which can be expressed as ammonia nitrogen, artificial bait made of mackerels intestine showed the fastest degradation rate. In order to evaluate the effect of artificial bait on marine ecosystem, seawater qualities including SS, COD, DO, nitrogen, phosphorus were determined depending on depth and location during 2 days test operation period. It is apparent that the effect of artificial bait on seawater quality was negligible when comparing seawater quality of test operation area with control area.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.326-332
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• 1990

The chemical attractants for sea eels, Astroconger myriaster, were identified by using fish traps in their natural habitat around namhae island, southern part of Korea. The ethyl alcohol extracts of anchovy, Engraulis japonica, which was a very good baits for sea eels showed higher attraction activities than residuals of it. Because sea eels showed high attraction activities to the free amino acid or nucleotides of synthetic anchovy extract, the succeeding experiment was conducted to identify the major chemical attractants among 9 free amino acid and 2 nucleotides by omission test. L-Glutamic acid, L-glycine, taurine, L-methionine or IMP showed highest attraction activities among 11 chemical compounds. But sea eels showed significantly weaker attraction activities to the synthethic extracts and single component than to the natural extract.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.3
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• pp.184-193
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• 2008

For environment-friendly fishery, the lead sinkers of octopus drift line were developed with the environmentfriendly sinker, and their characteristics and performance were investigated. To make the environmentfriendly sinker, the hydrate ceramic material was developed, and to increase the weight and strength, the iron power was added to it. The fishing hook was machine-made, and standardized, by using 60cm iron wire. For the manufacture of the sinker, the first, the mold was made, and then, hydrate ceramic material and water were quantitatively mixed. The mixture was poured into the mold prepared with a fishing hook already inserted, and had hardened for several hour, before it was taken out of the mold as a complete sinker. The sinkers were made in the 8 types ranging in weight from 150 to 500g, and their specific gravities were diverse from 2.871 to 6.637, which was 0.19 to 0.44 times lower than that of lead. The movement of the environment-friendly sinker by flume tank was possible in the weaker current speed than the similar lead sinker. In the coastal fishing grounds of Gangwon province, the comparison of catching efficiency was made between the improved fishing gears composed of the environment-friendly sinkers and artificial baits, and the current used fishing gears of lead sinkers and pig-fat baits. The result showed the tendency in which the improved fishing gears caught the bigger octopuses than the current used fishing gears. In the quantity and number of the fish catch per unit fishing gear, the improved fishing gear showed a little more catch than the current used fishing gear, regardless of the fishing area. However, the number of the improved fishing gears lost during fishing operation was similar to that of the current used fishing gears.

• Parasites, Hosts and Diseases
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• v.44 no.3
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• pp.255-257
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• 2006

A field trial on the control effect of fipronil poison bait against German cockroaches (Blatella germanica) was carried out at different restaurant types in Sinchon, Seoul, Republic of Korea. Monitoring was performed applying food baited traps for 2 days per week. Reduction rates of German cockroaches by applying fipronil baits were 90.9% at Korean restaurants, 96.4% at Chinese restaurants, and 89.4% in beer hall kitchens after 4 weeks of the treatment. Overall average of the reduction rate was 93.9%. As the natural reduction rate at untreated restaurants was 11.5% after 4 weeks, a correction of the average reduction rate by applying the Abbot formula was 93.1 %.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.8
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• pp.129-136
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• 2018

Termites are important sub-baits of natural ecosystems and are beneficial insects that are natural decomposer. However, the building materials used by human beings can not coexist with each other on timber which is a termite food. As of 2017, due to fertile forests, warming, and the spread of boilers, termite damage to timber construction is increasingly occurring day by day. Currently, Korea utilizes fumigation, Beit system, preserved wood, etc. of chemical products as termite control measures. But in the case of control measures, timber that has already been eaten by termites can not serve as a structural material and must be repaired. On the other hand, in the case of overseas, Scale of damage to termites the influence on the construction is also large, and a lot of research has been carried out on the prevention methods. In this thesis, investigate such foreign control measures, Would like to suggest a suitable method for Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.2
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• pp.85-91
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• 1983

The behaviour of shrimp in response to the trap was much influenced by the type, size and the dimensions of entrance as well as physiological and ecological conditions. The entry and the escape behaviour of shrimp to the model trap were observed in accordance with netting materials, baits, type and slope of entrance, and gathering response were also investigated on the odour of bait extracts in the aquarium from June to August, 1983. Entering shrimp to the circular entrance was significantly more than to the triangular or the square; however, no differences were found in the entry behacior among netting materials i e., P. A, P. E. and cotton. According as the slope of entrance was increased its angle from 0$^{\circ}$ to 90$^{\circ}$, number of entering shrimp was decreased; however, number of escaping shrimp at 30$^{\circ}$or 60$^{\circ}$ with time was fewer than at 0$^{\circ}$ or 90$^{\circ}$. Gathering responses of shrimp on the odours were more sensitive to the flesh of mackerel or the shrimp than to the pickled anchovy, or the pettitioes, while no differences were found between another bait extracts, i e., the shrimp and the flesh of mackerel, the short-necked clam and the horse mackerel, the flesh and the viscera of mackerel.