• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.3
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• pp.232-239
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• 2001

For the purpose of providing the basic data on the improved fishing gear and the man power saving, which contribute to enhance fishing efficiency of set net in the coast of Jeju Island, this study analyzed the catch of two fishing place for the past 3 years in order to compare the fishing efficiency between rectngular set net and pound net, which have been used for fishing with being attached to the set net fishing place in coast of Jeiu Island, Thereby the result is as follows ; 1. When using pound net, the total amount of catch during 1997 to 1999 was 2 times more than that of when using rectangular set net. 2. When using Pound net, the catch of squid, mackerel, rabbit fish and Yellow tail during 1997 to 1999 was 1.8 times more than that of when using rectangular set net.. 3. In case of rectangular set net, CPUE marked 10.1㎏ with horse amckerel, 20.5㎏ with squid, 18.0㎏ with rabbit fish and 2.2㎏ with Yellow tail, and in case of pound net, CPUE marked 57.5 ㎏ with horse mackerel, 30.0㎏ with squid, 25.0 with rabbit fish and 4.7㎏ with yellow tail, and on the whole CPUE of poind net marked higher. 4. In case of rectangular set net, the catch ratio for fishing operation marked 64% with horse mackerel, 79% with squid, 39% with rabbit fish and 14% with yellow tail, and in case of pound net, the catch ratio fishing operation marked 18% with horse mackerel, 85% with souid 40% with rabbit fish and 14% with yellow tail, and accordingly it showed the result that the catch ratio for fishing operation was higher with the case of rectangular set net, but higher with the case of pound net.

• Ocean Science Journal
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• v.40 no.1
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• pp.11-16
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• 2005

Correction factors based on the catch ratios of egg and larval densities in the southern waters of Korea were estimated for anchovy Engraulis japonica. This was undertaken in order to adjust ichthyoplankton data from different sampling methods, gear types and time. Samples were collected during ichthyop1ankton surveys in Korean waters from 1983 to 1994. The ratios for egg densities obtained in vertical tows with a NORPAC net (ring $\Phi$, 45 cm) compared to those obtained in oblique tows with a KOB net (ring $\Phi$, 80 cm) were 0.86 (CV = 0.65), 1.22 (CV = 0.36), and 0.93 (CV = 0.42) for early, middle, and later developmental stages, respectively. The ratios for larval densities for vertical and oblique tows varied depending on size. For yolk-sac and small larvae (< 4 mm), the ratios were 3.08 (CV = 0.45) and 1.98 (CV = 1.34), while those of 4-6 mm, 6-8 mm, and 8-10 mm larvae were 0.44 (CV = 1.31), 0.45 (CV = 1.70), and 0.56 (CV = 2.50), respectively. Ratios of day/night densities for larvae of 4-10 mm lengths were lower (0.01-0.06) in offshore catches than values obtained in coastal areas (0.440.46) and similar values (0.16-0.04) for vertical and oblique tows. Our results indicated that vertical towing is more efficient for sampling early life stages (from eggs to larvae less than 4 mm long), while oblique towing is more efficient for larvae longer than 4 mm due to depth preferences for each developmental stage (e.g., changes in egg buoyancy and vertical migration oflarvae).

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.218-228
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• 2007

Modem concepts of gait rehabilitation after stroke favor a task-specific repetitive approach. In practice, the required physical effort of the therapists limits the realization of this approach. Therefore, a mechanized gait trainer enabling nonambulatory patients to have the repetitive practice of a gait-like movement without overstraining therapists was constructed. In this study, we developed an active gait training system for patients with gait disorder. This system provides joint movements to patients who cannot carry out an independent gait. It provides a normal stance-swing ratio of 60:40 using an eccentric configuration of two gears. Joint motions of the knee and the ankle were evaluated with using the 3D motion analysis system and compared with the results from the multi-body dynamics simulation. In addition, clinical investigations were also performed for low stroke patients during the 6-week gait training. Results from the dynamics simulation showed that joint movements of the knee and the ankle were affected by the gear size, the step length and the length of the foot plate, except the radius of curvature of the foot guide plate. Also, the 6-week gait training revealed relevant improvements of the gait ability in all low subjects. Functional ambulation category levels of subjects after training were 2 in three patients and 1 in a patient. The developed active gait trainer seems feasible as an adjunctive tool in gait rehabilitation after stroke.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.173-182
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• 2011

The purpose of this paper is to provide useful information for fishermen in the manner of investigation a sinking speed of current type tuna longline gear at the North Pacific Ocean as a new developed tuna longline fishing ground. The sinking depth of mainline in connection with different basket was investigated. The experiments were also performed with different materials such as Supermansen (i.e., PE) and Hitech (i.e., PA) for the mainline to investigate the sinking depth of mainline and hooks. Furthermore, the relation between the sinking depth of hooks and catches are investigated also. The sinking depth of mainline at the first and the last shooting basket shows deeper than that of middle part of a basket due to reduced shortening ratio. The sinking depth of mainline and hook with Hitech material shows more shallow than that of Supermanse material, even the Hitech case was designed to sink deeper than that of Supermanse case. The highest catches arise at the middle part basket as the hook number 7 with around 248m sinking depth. From the results, longline with Hitech material is needed to increase the sinking force for reaching the relevant sinking depth. Moreover, the current strength at the North Pacific Ocean will be considered for further commercial fishing.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.4
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• pp.318-327
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• 2012

The operating sound radiated from a laser printer includes tonal noise components caused by the rotating mechanical parts such as gear, shaft, motor, fan, etc. The negative effects of the tonal noise components need to be considered in the process of developing a sound quality index for the quantitative evaluation of the emotional satisfaction in terms of psycho-acoustics. However, in a previous paper, it was confirmed that the Aures tonality did not have enough correlation with the results of jury evaluation. The sound quality index based on loudness, articulation index, fluctuation strength has a little problem in considering the effects of rotating mechanical parts on the sound quality. In this paper, to solve the tonality evaluation problem, the calculation algorithm of Aures tonality was investigated in detail to find the cause of decreasing the correlation. The new tonality evaluation model was proposed by modifying and optimizing the masking effect, loudness ratio, and shape of weighting curve based on the basic algorithm of Aures tonality, and applied to two kinds of operating sound groups in order to verify the usefulness of proposed model. As a result, it is confirmed that the proposed tonality evaluation model has enough correlation and usefulness for expressing the tonalness in the operating sounds of laser printers. In the following paper, this results will be used to model the sound quality index as the input data by using the classification algorithm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.195-202
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• 2006

To determine the relative efficiency and mesh selectivity of gill net for the Pacific saury, Cololabis saira, a series of fishing experiments was carried out in the Northwest Pacific Ocean from August 13 to October 13 in 2002, using gill nets of different mesh size(30, 33, 35, 37, 39 and 42mm) constructed from two kinds of twine material(monofilament, twisted multifilament nylon web). The relative efficiency of two material gears was expressed as the ratio obtained by dividing monofilament catch by multifilament catch in number. The master selection curve of each material gear was estimated by applying the extended Kitahara's method. The catch of experimental gears is mostly Pacific saury(98.6%), Cololabis saira. The kinds of bycatch are common squid(0.7%), Pacific mackerel(0.6%), etc. Catch comparisons in the two gears showed that monofilament nylon nets are 1.7 times more efficient. The optimum values in monofilament and multifilament gill net for Pacific saury are 8.28 and 8.23, respectively.

• Journal of Korea Technology Innovation Society
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• v.20 no.3
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• pp.664-683
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• 2017

The technology transfers from public institutions have positioned themselves as knowledge conduits for stimulating firms' capabilities under 'catching-up' economy paradigm. While this view is still relevant, the policy for public technology needs to be extended to a more marketoriented way. This study explores how public technology affects the financial performance of demanding companies by comparing the revenues and profits of 'technology commercialised group (TC)' and 'in-house research group (InR)'. The estimation results by hierarchy regression suggest that the size and the patents of TC firms have a more influential impact than InR group, although the ratio of maintaining research staff was reported an inverse relation. The contribution to the operating profit seems to be indifferent between the groups. The positive impact of public technology over the firm's performance is highly related to the technology commercialisation capability, signalling that the aim of technology transfer needs to gear toward the enhancement of commercialising capabilities rather than the promotion of technology transactions.

• The Journal of Fisheries Business Administration
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• v.8 no.2
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• pp.1-19
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• 1977

The results analyzed of the actual state of medium size two-boat trawler fishery based on the cost expended in 1975 are as follows: According to the calculation of interest, the total cost of this fishery comes to ￦ 55,353,807, and in this account, the production cost comes to ￦ 49,747,383 (89.9%) and the material cost comes to ￦ 27,027,662(48.8%), the labour cost comes to ￦ 10,381,013 (18.8%) the expenses, ￦12,338,708(22.3%) and commision and interest comes to ￦ 5,606,424 (10.1%). As above the fishery comes is 90% of production cost for the expense of production. The ratio of cost element to the total cost 100 is as follow: Fuel: 23.6%, allocation: 14.3%, fishing gear: 14.1%, boat repair: 13.0%, fish box: 8.5%, ice: 14.1%, commission: 6.9%, food cost: 4.5%, interest: 3.2%, transportation fee: 2.8%, consumption: 2.6%, tax: 2.5%, depreciation: 2.4%, administrative expense: 1.6%. The unit cost of catches to each box, including the interest, cames to ￦ 2,167 and not calculating the interest it comes to ￦ 2,098. The cost production to each kg comes to ￦ 114 including interest, without interest, it comes ￦110. When the production cost comes to 90.6%, it comes to 9.4% of total revenue. The reason which this fishery brings low income is that the boats are almost old and semi-diesel engine is used. So, fuel expense and repaire expenses needs too much. Acconding to above this fishery needs to replace new boat and new engine. And new are for this fishery needs to bring under cultivation in order to bring good income with the new method for this fishery. Specially, this fishery brings low income from July to September because of its rest from labour. And so, the expenses, item, and account of money, and the trust money the cost element are not showed in August.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.5
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• pp.22-33
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• 2000

Since the heavy-duty power manipulator generally has high ratio gear reducers at its joints, its dynamic characteristics is much slower than that of the master manipulator and it is likely to encounter the saturation in the input magnitude when it is used as the slave manipulator in telemanipulation systems. This paper proposes a force reflecting and compliant control scheme for the heavy-duty power telemanipulator. The main advantage of the proposed scheme is that it provides a precise position and compliant control performance for a telemanipulator with control input saturation. The stability of the proposed scheme is analyzed and a series of experiments shows its performance.

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.637-643
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• 2014

This study aims to explore a set of indicators to be used for purification management. by estimating the total quantity of depositied waste in coastal waters, Through 3 rounds of Delphi technique, this study sorts out the following 5 variables to be used as major indicators determining priorities for purification in coastal areas: the ratio of re-deposition after collection, the area where fishing gear are lost, the total quantity of depositied waste of each coastal water, the total quantity of deposited waste in the past, and the quantity of depositied waste by unit area. Although the fact that the delphi surveys were done only on 27 specialists limits its external validity, this study will serve as a base for in-depth studies with more expanded panels that will provide better indicators for purification management in coastal waters of Korea.