• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.284-291
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• 2014

Finely-striate buccinum Buccinum striatissimum, a species of whelks, is caught mainly by pot in the eastern coastal waters of Korea. In order to determine the size selectivity of pot for the species, comparative fishing experiments were conducted near Yeongil Bay from June to September in 2003 using the dome-shaped pots with different five mesh sizes (17.1, 24.8, 35.3, 39.8, and 48.3 mm). The parameters of logistic equation were estimated by the SELECT (Share Each Length's Catch Total) method based on a multinomial distribution. The model with the estimated split parameter was found to fit the catch data best. The master selection curve was estimated to be s (R)=exp (13.044R-16.438)/[1 + exp (13.044R-16.438)], where R is the ratio of shell height to mesh size. The relative shell height of 50% retention was 1.260, and the selection range was 0.168. Enlargement in mesh size of the pot allows more small-sized whelks to escape.

• Communications for Statistical Applications and Methods
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• v.24 no.1
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• pp.97-113
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• 2017

This paper proposes a method for sufficient dimension reduction (SDR) of mixture data. We consider mixture data containing more than one component that have distinct central subspaces. We adopt an approach of a model-based sliced inverse regression (MSIR) to the mixture data in a simple and intuitive manner. We employed mixture probabilistic principal component analysis (MPPCA) to estimate each central subspaces and cluster the data points. The results from simulation studies and a real data set show that our method is satisfactory to catch appropriate central spaces and is also robust regardless of the number of slices chosen. Discussions about root selection, estimation accuracy, and classification with initial value issues of MPPCA and its related simulation results are also provided.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.2
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• pp.197-207
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• 1996

The proportion of log-associated school catches by Korean tuna purse seiners in the western Pacific has shown a declining trend until recent years. During the period $1990\~1995$, log-associated school catches contributed $34.6\%$ to the total Korean tuna purse seine catch, representing quite a low level compared to the early phase of the purse seine fishery. Species compositions of both log-associated and free-school catches showed that skipjack, Katswonus pelamis, was dominant species and yellowfin, Thunnus albacares, followed, with the small amount of bigeye tunas, T. obesus, Yellowfin proportion was higher in free-school catches than in log-associated school catches. Log-associated school catches monitored during the scientific observation period were made of $60\%$ skipjack, $38\%$ yellowfin, and $2\%$ bigeye tunas, indicating the low skipjack and high yellowfin proportion compared with historical fisheries data based on logbooks. A total of 11 by-catch species were identified, of which sharks occurred together with tunas in all sets and yellowtail kingfish was the most abundant by-catch species. From the length distribution it was found that small yellowfin less than 70 cm mainly distributed around floating objects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.37-47
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• 1977

Korea started the Atlantic tuna fishery from 1964 by means of longline, then added bait-boats in 1972. Both fisheries have given the top priority to catch yellowfin tuna(Thunnus albacares). The paper reviews available catch, effort and biological data, estimates some population parameters in order to understand the status of the Atlantic yellowfin tuna as a whole. The main findings are summarized as follows: 1. The total of 476 million hook-equivalent fishing effort was thrown to catch yellowfin tuna in 1974, among which one thired was shared by longliners. 2. The dominant age group becomes younger in both surface and longline fisheries. 3. The recent mortality coefficients were calculated as 1.5 for total mortality and 0.7 for fishing mortality. 4. The weight at recruitment was 2.7 kg in 1973 which was smaller than the regulation size(3.2kg) proposed by ICCAT. 5. The maximum sustained yield was calculated to 95-145 thousand metric tons, which was the level of recent catch. Therefore, it is apparent that the present yellowfin tuna fishery should continue to receive close attention.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.294-305
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• 1989

Basedon statistical data of pomfret (Pampus spp.) catches by the stow net during $1970\~1985$, the distribution and migration of pomfrets and fishing conditions were investigated in relation to oceanographic conditions, in the East China Sea and the Yellow Sea. The main fishing grounds of Pomfrets were formed around the Great Yangtze Sand Bank which locates between the Cheju Island and the mouth of the Yangtze River. Its area occupied only 11 percent of all fishing grounds, and about 70 percent of total catch was found there. The coefficient of variation(CV) in catch was below 0.01 in the whole fishing grounds and that of tile main fishing grounds (14 fishing areas) was $0.001\~0.003$. This area was indicated markedly by the inflow of Yellow Sea Warm Current from spring to autumn, and this mixing area which formed the oceanic front among the China Continental Shelf Water, the Yellow Sea Bottom Cold Water and the Tsushima Warm Current. The pomfrets migrates to south-north according to the expansion and contraction of the Tsushima Warm Current including the Yellow Sea Warm Current and the Yellow Sea Bottom Cold Water. Therefore, it migrates to north of the Yellow Sea in summer and to southern part of the East China Sea in winter. The most frequent range of the water type for high catch was $10\~12^{\circ}C$ in temperature and $32.4\~33.4\%_{circ}$ in salinity. The ranges was occupied more than 70 percent of total catch on fishing season. The frequency range of the water type was not different between the abundant fishing periods and the poor fishing periods in terms of the maximum catches.

• Journal of Engineering Education Research
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• v.17 no.4
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• pp.15-20
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• 2014

The non-contact easy detecting system of nursing person's body vital information and their behaviors monitoring system are developed, which consist of "Kinect" sensor and thermography camera. The "Kinect" sensor can catch the body contour and the body moving behavior, and output their imaging data realtime. The thermography camera can detect respiration state and body temperature, etc. In this study, the practicability of this system was verified.

• 한국데이터정보과학회:학술대회논문집
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• 2006.11a
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• pp.9-20
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• 2006

Even though there are lots of learning theory and learning Instruments today, it is still difficult to teach the children individually taking their learning ability into consideration. In this case lower level children may be discouraged and cannot catch up the next course. The purpose of this paper is to design and develop webb-based courseware on arithmetics for the disabled children and apply the program to the class field. This program is very useful for the left-behind children because it enables the repetitive and visible learning.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.110-112
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• 2003

The researchers, who seek geological and environmental information, depend on the remote sensing and aerial photographic datum from various commercial satellites and aircraft. However, the adverse weather conditions and the expensive equipment can restrict that the researcher can collect their data anywhere and any time. To allow for better flexibility, we have developed a compact, a multispectral automatic Aerial photographic system. This system's Multi-spectral camera can catch the visible (RGB) and infrared (NIR) bands (3032${\ast}$2008 pixel) image. Our system consists of a thermal infrared camera and automatic balance control, and it managed and controlled by a palm-top computer. And it includes a camera gimbals system, GPS receiver, weather sensor and etc. As a result, we have successfully tested its ability to acquire aerial photography, weather data, as well as GPS data, making it a very flexible tool for environmental data monitoring.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.423-429
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• 2001

Prediction of the variation in annual biomass was conducted for the white croaker. Argyrosomus argentatus in Korean waters using leslie Matrix, based upon fishery data for the past 21 years and biological data, We used density-independent and density-dependent Leslie Matrix models. Similar parameters were estimated from two models except that the density-dependent model was influenced by the density effect variable, q(i,t), The eigenvalue of the white croaker population for the $1984\~1995$ period was estimated to be 0.8, indicating a declining pattern of the population. The survival rate of 0-th year class was calculated to be 0.00005. Based on the schedule of the age-specific survival rate and fecundity, the future biomass and catch was predicted for various levels of fishing mortalities (F), If F was set at 0.252/yr ($F_{35x}$) or 0.368/yr ($F_{0.1}$), the biomass and catch increased, and if F was set at 0.922 ($F_{current}$), the biomass and catch decreased, The fishing mortality at equilibrium was estimated to be 0.7/yr. Finally, the management strategy of the white croaker was discussed.

• Journal of Digital Convergence
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• v.10 no.2
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• pp.63-71
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• 2012

This paper investigates efficiency analysis to IT HRD programs in the dynamic perspective. First, empirical result shows that government fund of IT research center is significantly associated with SCI thesis and the more trial goods and SW development is connected with the more patent and technology transfer. Second, ITRC program has been operated efficiently since 2000. Finally, dynamic efficiency analysis implicates that ITRC program is more efficient than other IT SoC program and foreign student support program. The reason why ITRC program is more efficient is generated not from the effect of imitation by catch-up strategy to developed HRD programs, but new operation system introducing and utilizing HRD performance system.