• 한국농공학회지
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• 제17권3호
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• pp.3878-3884
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• 1975

This study was carried out to develop the throw-in type thresher with its size as small as possible. Developing the smallest possible size of the throw-in type thresher has been very important to increase mobility and to reduce the machine price. The thresher that developed for this purpose was tested as to threshing and separation performance for the samples collected in eight catch boxes under the concave while threshing. The amount of grain collected in each compartments was measured and the threshing and separating pattern along the total span of the threshing drum was determined. The performance of separating and threshing units of the test thresher and threshing loss was evaluated by use of the developed grain separating apparatus and the method for measuring the grain separating performance of threshers. The results are summarized as follows; 1. The unthreshed grain (drum losses) and semi-threshed grain did not appeared at all throughout the treatments. 2. When threshed by making use of the developed throw-in type thresher, the threshing grain loss at about 25 per cent grain moisture was about one-half when threshed at about 18 per cent grain moisture. 3. And its grain separating loss in higher feed rate was decreased in comparison with that of lower feed rate. These results suggests that the throw-in type thresher may be suitable for wet threshing and for higher feed rate of threshing. 4. Above 60 per cent of total grain passing through concave fell through the screen within a scant 30 cm from the feeding inlet. This threshing pattern may suggest that major threshing action may be finished before about one third of cylinder length. The required separating load extended over the whole drum span is so defferent that separating elements should be redesigned so as to accomodate this variable pattern of separation load. 5. It was apparent from the experiment that the length of the threshing drum of the throw-in type thresher could be reduced from 1285mm to about 1050mm without increasing grain separation loss greatly.

• 수산해양기술연구
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• 제43권4호
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• pp.310-319
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• 2007

To investigate the catches of squid jigging fishery, a series of fishing experiments was conducted in the high seas of the Northwest Pacific($40^{\circ}-43^{\circ}N$, $150^{\circ}-155^{\circ}E$) during the period of 1 August to 22 October 2005 by commercial fishing vessel. The number of 142 test fishing was carried out in the Northwest Pacific during 83days. The total catch were 47,524kg as 4 squid species and CPUE was $8.9kg/line{\cdot}day$. CPUE showed high values in the frontal zone during the survey. Main squid species caught from the experimental fishing were the neon flying squid, Ommastrephes bartrami(96.8%) and the boreopacific gonate squid, Gonatopsis borealis(3.2%). Dorsal mantle length of the neon flying squid were increased by the time and increasing of the hook size. Loss rate of the neon flying squid in the water showed the highest values in 28.2% compare to the others. And the loss rate of the front roller and in the air were 1.1% and 1.0%, respectively.

• 수산해양기술연구
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• 제33권2호
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• pp.90-96
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• 1997

민꽃게를 대상으로 하는 통발 어구에 관한 지금까지의 연구가 통발의 형상, 입구의 수 등 주로 강조적인 측면을 개선하는데 주력하였을 뿐 민꽃게의 은신행동 등 민꽃게 자체의 기본적 습성을 충분히 이용하였다고는 볼 수 없고, 그물 통발이 가지는 민꽃게 수입 성능상의 한계점을 근본적으로 개선하지는 못하였다고 생각되었기에 본 연구에서는 민꽃게의 수입 성능적 그물 통발은 한계가 있다고 보고, 민꽃게의 습성을 고도로 이용함으로써 수입성능을 높일 수 있는 2종류의 어구를 고\ulcorner 하여 수조실험과 해상실험을 통해 금.고(1987, 1990)가 개발한 통발과 비교 실험을 행하였다. 실험에서 얻어진 결과를 요약하면 다음과 같다. 1) 그물 통발과 파이프형 통발에서 시간의 경과에 따른 민꽃게의 접촉율과 반응율은 금.고(1987.1990)가 행한 사구식 각주형 그물 통발의 실험 결과와 대체로 일치하였지만, 평판형 얽애그물에서는 접촉율이 잠깐 증가하였다가 바로 감소하였고, 반응율은 급히 증가하기 시작하여 최대치를 보인 후 일정해지는 경향을 나타내 차이가 있었다. 2) 민꽃게의 입농시작 시간은 평판형 얽애그물에서 민꽃게가 그물에 접촉하기만 하면 신체의 일부분이 곧바로 그물에 얽혀버렸기 때문에 포획에 걸리는 시간이 다른 통발 어구에 비해 가장 짧게 나타났고, 다음이 파이프형 통발이며 그물 통발에서 가장 늦게 나타났다. 3) 민꽃게의 통발내 분포율을 나타내는 접촉율 곡선과 반응율곡선과의 시폭은 평판형 얽애그물에서 가장 빨리 그리고 많이 벌어져 민꽃게의 체포자체에 있어서는 그 성능이 가장 우수하게 나타났으며, 파이프형 통발의 경우 직경의 차이(${\phi}$ 150, 250mm)에 따라서는 큰 차이를 보이지 않았지만, 그물 통발에 비해 성능이 높게 나타났다. 4) 파이프형 통발은 입농한 민꽃게에 대해 통발내에서 정제하는 은신행동을 수발하게 하여 민꽃게의 은신처로 작용한다는 것을 알 수 있었다. 5)그물 통발과 파이프형 통발 및 평판형 얽애그물에 대한 어획 실험에서 어구 하나당 평균 어획량은 파이프형 통발에서 가장 많았고, 다음이 그물통발이였으며, 평판형 얽애 그물에서 가장 적어 수조실험과는 차이를 보였다.

• Journal of Computing Science and Engineering
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• 제2권1호
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• pp.1-25
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• 2008

Spoken dialog tasks incur many errors including speech recognition errors, understanding errors, and even dialog management errors. These errors create a big gap between the user's intention and the system's understanding, which eventually results in a misinterpretation. To fill in the gap, people in human-to-human dialogs try to clarify the major causes of the misunderstanding to selectively correct them. This paper presents a method of clarification techniques to human-to-machine spoken dialog systems. We viewed the clarification dialog as a two-step problem-Belief confirmation and Clarification strategy establishment. To confirm the belief, we organized the clarification process into three systematic phases. In the belief confirmation phase, we consider the overall dialog system's processes including speech recognition, language understanding and semantic slot and value pairs for clarification dialog management. A clarification expert is developed for establishing clarification dialog strategy. In addition, we proposed a new design of plugging clarification dialog module in a given expert based dialog system. The experiment results demonstrate that the error verifiers effectively catch the word and utterance-level semantic errors and the clarification experts actually increase the dialog success rate and the dialog efficiency.

• 한국수산과학회지
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• 제44권4호
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• pp.397-402
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• 2011

We surveyed the bycatch and discard of the shrimp-pot fishery in Hokkaido, Japan, three times during the major fishing period in September 2005. The surveyed catches were analyzed to separate bycatch, discard, and landings. To analyze bycatch and discard, we randomly selected 2 shrimp pots from each of 7 sets, for a total of 14 pots per survey. The total bycatch and discards from the rest of the shrimp pots were also analyzed in each survey. The total catch averaged 12 species. Coonstripe and pink shrimp catches averaged 74.7 kg/haul and 12.7 kg/haul, respectively. The weight of the bycatch averaged 33.4 kg/haul. The bycatch consisted mainly of snail fishes(5.1%), brittle stars(5.0%), and short-spined sea urchins(4.1%). Our analysis showed that the ratio of discard was 0.38, the rate of the discard was 27.4%, and the discard per unit effort was 33.4 kg/haul. The Hokkaido shrimp-pot fishermen discarded all of the bycatch except shrimps. Hence, the weight of the bycatch was equal to the weight of the discard. Our results comprise preliminary data that can be used to find ways to reduce bycatch and discard in the shrimp-pot fishery.

• Ocean and Polar Research
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• 제28권4호
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• pp.439-449
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• 2006

This study was aimed at measuring the fishing capacity of Powered Anchovy Drag Net Fisheries (PADNF) in Korea using Peak-to-Peak(PTP) and Data Envelopment Analysis(DEA) methods recommended by FAO. In the analysis, both fishing capacities of total PADNF and individual PADNF vessels were measured with time series data and cross sectional data, respectively. In addition, the results of the DEA measurement were analyzed in order to determine reduction levels of fishing capacity. In case of total PADNF, the results by rn and DEA methods showed a similar rate of capacity utilization (79%), indicating the capacity was not utilized enough. In addition, the sensitivity analysis suggested that the number of vessels should be reduced by 20%, and the gross tonnage and the horse power should be reduced by 20% and 21%, respectively if the current catch is to stay at the 2004 level. The DEA results on individual PADNF vessels indicated the capacity utilization was 75% on average, showing some differences in capacity utilization among vessels (31%-100%). The results of the study would be useful for measuring production efficiency in PADNF. They would also provide good policy information for efficient use of resources and capacity reduction levels, which are useful far vessel buyback programs of coastal and offshore fisheries.

• 한국수산과학회지
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• 제4권1호
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• pp.1-6
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• 1971

In order to study the catching efficiency of shrimp trawl equipped with electrodes around the net mouth and stimulant devices attached to the ground rope, an experimental operation was carried out at Oma-Island Shrimp Farm from October 3rd to November 5th, 1970. Many studies have been made on the shrimp trawl with electric stimulant devices, but few can be found for detailed scientific catching methods. Electric power consumption was so excessive that electric stimulant devices could not be developed for commercial purposes. As a first step toward the successive operations of the electric stimulant devices in the field, it is necessary to study fundamental principles, such as electric current, voltage, electric potential, potential difference, electric field and suitable pulse. The behaviour response of the common shrimp, Penaeus japonicus BATE to moving nets and electric stimulant devices were reported in the preceding papers based on the water tank experiments (Ko and Kim, 1970). Through comparative fishing tests the rate of catching efficiency during daylight time was confirmed to be from 89 to 96 per cent of the night catch efficiency, and with 30 V. 1.5 A. electric power was sufficent for practical sea operation.

• 한국수산과학회지
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• 제39권4호
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• pp.344-348
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• 2006

The ecological characteristics and stock biomass of the Shiba shrimp, Metapenaeus joyneri, in Korean waters were determined, using fishery data from the Ministry of Maritime Affairs and Fisheries (MOMAF) and available length frequency data. The instantaneous coefficient of total mortality (Z) of M. joyneri was estimated to be 4.191year, and the annual survival rate (S) was 0.015. The estimated instantaneous coefficient of fishing mortality (F) for recent years was calculated to be 1.94/year. The age at first capture of M. joyneri was 0.71 years. Based on these parameters, the annual biomass of the M. joyneri stock was estimated using a biomass-based cohort analysis and data on the annual catch in weight at age for 1993-2004 in Korean waters. During the study period, the biomass of the shrimp peaked in 1994 at about 9,082 metric tons. Subsequently, it decreased to 500 metric tons in 1998.

• 제어로봇시스템학회논문지
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• 제21권5호
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• pp.490-495
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• 2015

As flying robots are becoming popular, there are increased needs to use themforsuch purposes as parcel delivery, serving in restaurants, and stage performances. To control flying robots such as quad copters, localization is essential. In order to properly position flying robots, many techniques are in development, including IR (infra-red)-based systemswhich catch markers on a flying robot in order that it can position itself. However, this technique demonstrates only short coverage. Furthermore, localization from inertial sensors diverges as time passes. For this reason, this paper suggests a TWR (two-way ranging) based positioning technique. Despite the weaknesses in currently available TWR system, this paper suggests a self-positioning and outlier detection technique in order to provide reliable position information with a faster update rate. The self-positioning system sends a shorter message which reduces wireless traffic. By detecting and removing outlier measurements, a positioning result with better accuracy is acquired. Finally, this paper shows that the suggesting system detects outlierssequentially from less than half the number of anchors in localization system according to the degree of outlier in measurement and the noise level. By performing an outlier algorithm, better positioning accuracy is acquired as shown in the experimental result.

• 수산해양기술연구
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• 제28권4호
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• pp.360-370
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• 1992

In order to analyse the mesh selectivity for the trawl net, the fishing experiment was carried out by the training ship Saebada belonging to the National Fisheries University, in the Southern Korea Sea and the East China Sea from June 1991 to August 1992. The trawl net used in the experiment has the trouser type of cod-end with cover net and the mesh selectivity in the cod-end part. In this report, the species of fishes caught and the catch rate for them in accordance with different mesh sizes were analysed, and the result obtained are summarized as follows: 1) 145 species of aquatic animals were caught in totally 138 times of trawl operations. 2) The number of species mostly not to escape are 28, 22, 19, 16 and 11 respectively, in each opening mesh size, 51.2mm, 70.2mm, 77.6mm, 88.0mm and 111.3mm of cod-end. 3) In view that the use of the opening mesh size above 54mm in cod-end of trawl net in Korea, it is necessary to device a counterplan against the overfishing, for the 22 species of aquatic animals mostly not to escape in the cod-end of the large mesh sizes more than 70.2mm.