• Journal of Animal Environmental Science
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• v.12 no.2
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• pp.51-60
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• 2006

Studies were carried out using growing to finishing pigs to investigate adequate floor space ($m^2/pig$) in Jeju environment. A randomized block design was used to compare the effect of pig performance on 3 stocking rates (low $0.56 m^2/pig$, medium 0.70 and high 0.90). Liveweight gain and feed intake were measured over a 4 week(Growth stage 1 and Growth stage 2) period or a 3 week(Growth stage 3) period. In growth stage 1 (43 to 65 kg body weight ; BW), daily weight gain was significantly higher in the medium stocking rate than in low or high (P<0.05). However, no significant difference in daily weight gain was found among treatments in growth stage 2(65 to 91 kg) or 3 (91 to 105 kg). Dressing percentage, back fat thickness and carcass grade were also not different (P>0.05). In conclusion, daily weight gain of pigs reared in medium density appeared to be higher than in the other groups during the early growing period which is $0.70m^2/pig$ and similar to that recommended by National Livestock Research Institute, RDA.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.141-145
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• 2000

The daily fluctuations of occurrence rate and standing stock of zooplankton, the relationship between dry and wet weights of gelatinous zooplankton, and the size distributions of body length and body weight of zooplankton were investigated in the sea around Cheju Island from September 1996 to August 1997. Mean ratios of wet to dry weights were 66.46 (raging from 47.05 to 84.64) in the gelatinous zooplankton and 10.89 (raging 9.21 to 14.85) in the non-gelatinous zooplankton which consisted of crustaceans such as copepods, decapods, mysids, and ostracods etc. Rarios of gelatinous zooplankton to non-gelatinous zooplankton (G/NG) in wet weight was 0.99 (0.28-2.30), indicating high occurrence rate of gelatinous in the study area. The seasonal and diel fluctuations of the gelatinous zooplankton were very large, and G/NG ratios greatly varied with seasons and dat/night cycles. The size distributions of body length of zooplankton (250-500 urn: 35.5% in maximum), and wet (0.1-0.2 mg: 34.4%) and dry weights (0.025-0.05 mg: 44.8%) showed much difference depending composition of the zooplankton groups. These results show that quantitative estimations of zooplankton produc- tivity only based on wet weight should be corrected to better understand and evaluate marine resources in Korean waters.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.4
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• pp.311-320
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• 1997

We selected horse mackerel Trachurus japonicus, mackerel Scomber japonicus and arrow squid Todarodes pacificus, to be used in the experiment. These fishes migrate to the Cheju coast and were caught by set-net. We studied on the attracting effect and the leading effect on the fish school using incandescent lights in an outdoor water tank at the Marine Research Institute Cheju National University. The results obtained are summarized as follows; 1. The horse mackerels, mackerels and arrow squids were actively attracted to the incandescent light. The optimum illumination and the reactions of each fish school were different though. 2. We turned the first attracting lamp on and turned it off after ten minutes. Then we turned the second attracting lamp on and turned it off after another ten minutes. The reaction of each fish school was a little bit different, but it worked to lead them to their destination. 3. We turned the three attracting lamps on at the same tune. After ten minutes, We turned the first attracting lamp off. After another ten minutes we turned the second attracting lamp off. The reaction of each fish school was a bit different, but it worked to lead them to their destination. 4. One incandescent light was moving. The reaction of each fish school was a little bit different, but it worked to lead them to their destination.

• 한국해양학회지
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• v.22 no.1
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• pp.1-8
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• 1987

The Sinyangri Formation crops out in the vicinity of the Seongsan Peninsula, Cheju Island. Based on sedimentary structures, texture and composition, the lithologic sequence has been classified, in ascending stratigraphic order, into three lithofacies: parallel laminated sandstone facies (Facies I): conglomerate facies(Facies Il); and cross stratified sandstone facies (F acies Ill). Wedge-to-parallel, seaward-inclined in low angle less than 10$^{\circ}$lamina -sets with alternations of coarseand fine-grained sediments in the Facies I are the characteristic sedimentary structures in the foreshore depositional environment. Grains of this faciesare well sorted with good roundness compared with the other two facies, partly showing inverse graded bedding. Facies II,largely composed of claset-supported,very poorly-sorted conglomerates,does not pinch out but occurs continuously along the Sinyangri beach.Interstitial spaces between the clasts are mostly infilled with volcanic-ash and small amounts of well-rounded shell fragments.Maximum bed thickness as well as the size of imbedded basaltic clasts decreases to the south(toward Sinyangri). Large clasts with parallel lamination originated from the underlying Facies i,are generally elongated parallel to the bedding plane and display no systematic horizontal variations in size indicative of in-situ clasts.In view of the facts above it seems that large gravels from the basaltic rocks are transgressive lag conglomerates which are partly affected by the combination of longshore currents and propagating wave.Local occurrence of cross-strata dipping toward the south in the upper part of Facies IIreinforces the evidence of the action of longshore currents. Facies IIIis characterized by bidirectional trough cross-starifiction and wave ripples associated with the upper shoreface(surfzone) environments.In summary,the Sinyangri Formation represents the depositional environments of foreshore to upper shoreface truncated by disconformity between Facies Iand II.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.317-320
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• 2004

• 한국석유지질학회:학술대회논문집
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• spring
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• pp.38-41
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• 1998

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.603-605
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• 1999

In this paper, the aspects on modeling and control of an existing wind turbine are discussed. When designing control for variable-speed wind turbine, one deals with highly resonant, nonlinear dynamic systems subject to random excitation, i.e. wind turbulence. This requires good knowledge of the dynamics to be controlled. This paper describes an mathematical modeling of wind turbines with emphasis on control design for an existing wind turbine.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.331-338
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• 1996

The main aim of this study was to develop carrot soups with fishery products, which is improved from traditional gruel of Cheju island. For this the optimal procedure and ingredient mixing ratio for making basic carrot soup was determined through the instrumental measurement, the sensory evaluation and the nutrient analysis, and then the carrot-fishery soups were prepared by mixing the fishery products from Cheju island. The results were as follows: The optimal procedure for making basic carrot soup was to saute the sliced carrots and soaked rices with the sesame oil for 5 min, add the water, bring to a boil for 6 min, simmer for 15 min, then puree the soup. The optimal ingredient mixing ratio in the basic carrot soup was carrot 300 g: rice 45 g: water 900 $m\ell$: sesame oil 15 $m\ell$: salt 5 g. For preparing carrot-fishery soups were the optimal fishery products mixing ratio i) 30% tile fish or crab, ii) prawn, abalone, top shell, or ear shell 20%, iii) sea urchin 15%, iv) fusiform or gulf weed 5％. The order of sensory evaluation scores, on a 5-point scale, were sea urchin, crab > top shell, tile fish > abalone, ear shell > prawn > coral fish > fusiform, gulf weed. Nutrient composition analysis showed that vitamin A was 5 times higher in carrot soup than in pumpkin soup. Sensory evaluation scores show that carrot soup was prepared to pumpkin soup. A portion (200 g) of the soup would provide 144% of the recommended daily allowance of vitamin A. The results of this work indicate that an acceptable carrot-fishery soups of better nutritional and sensory values than pumpkin soup can be prepared.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.475-481
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• 1996

A simple, fast, inexpensive method hal been developed to extract organochlorine pesticide spiked in fish tissues by supercritical carbon dioxide. Following static supercritical fluid extraction (SFE), pesticides are collected by rapidly depressurizing the carbon dioxide effluent through a 0.79 mm i.d. metering valve into a capped screw-top tube. Percent recovers of standard organochlorine pesticides mixture (SOPM) increased with the decrease of the extraction temperature at 103 bar. Maximum average percent recovery of SOPM was 98% at $40^{\circ}C/172\;bar$ Average recoveries of SOPM spiked in Pacific cod, flatfish and common squid were 85,74,and 83% respectively at $40^{\circ}C/172\;bar$ Application of supercritical carbon dioxide ectraction offers and attractive alternative to the use of organic solvents for extraction of organochlorine pesticides from fish tissues.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.57-66
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• 1988

A series of experiments is performed to measure radon concentration in the near-surface soil gas at the four locations (Cheju-Si, Seoguipo-Si, Taejeong-eup, Seongsan-eup) in Cheju Island, using CR-39 detectors placed inside radon cups. Two types of radon cups are installed in shallow holes of about 15 cm in diameter and 50cm in depth. The optimum etching conditions, i.e., the concentration of NaOH solution, etchant temperature and etching time, are found to be 625N, $70^{\circ}C$ and 5.5 hours for CR-39 detectors. A typical conversion factor of radon cup is calculated as $$1track/mm^3{\cdot}30day=0.059Bq/{\ell}$$. Average radon concentrations over 30 days measured in Cheju Island from May 1, 1987 to April 23, 1988 are $3.1{\pm}0.3Bq/{\ell}$ for open radon cups and $1.7{\pm}0.2Bq/{\ell}$ for closed radon cups.