• Title/Summary/Keyword: Multiple fisheries

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Forecasting Total Marine Production through Multiple Time Series Model

  • Cho, Yong-Jun
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.1
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    • pp.63-76
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    • 2006
  • Marine production forecasting in fisheries is a crucial factor for managing and maintaining fishery resources. Thus this paper aims to generate a forecasting model of total marine production. The most generally method of time series model is to generate the most optimal single forecasting model. But the method could induce a different forecasting results when it does not properly infer a model To overcome the defect, I am trying to propose a single forecasting through multiple time series model. In other word, by comparing and integrating the output resulted from ARIMA and VAR model (which are typical method in a forecasting methodology), I tried to draw a forecasting. It is expected to produce more stable and delicate forecasting prospect than a single model. Through this, I generated 3 models on a yearly and monthly data basis and then here I present a forecasting from 2006 to 2010 through comparing and integrating 3 models. In conclusion, marine production is expected to show a decreasing tendency for the coming years.

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Incidence of Plasmids in Marine Bacteria Isolated from the Bunker-C Oil Enriched Culture (Bunker-C유 집식배양으로부터 해양세균 Plasmid의 분포)

  • Park, In-Sick;Park, Jung-Youn;Jin, Deuk-Hee;Hong, Yong-Ki
    • Microbiology and Biotechnology Letters
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    • v.16 no.4
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    • pp.270-274
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    • 1988
  • Samples used for the enrichment culture were collected from the sea water of suspected chronic petroleum contamination in the vicinity of Pusan, Chungmu and Ulsan ports, Korea. Alkaline Iysis and agarose gel electrophoresis techniques were employed to screen these isolates for the presence of plasmid DNA. There were n little differences in the percentage of isolates containing plasmids between sampling sites of unpolluted sen water (22%) and polluted son water (25%). Bacterial isolates taken from the Bunker-C oil enriched culture showed significantly more plasmid incidence (29%). About two thirds of strains grown on a variety of hydrocarbons were Gram negative strains of which 33% contained one or more plasmids. Multiple plasmids were observed in 23% of the plasmid-carrying strains. Forty one percent of the plasmids detected were estimated to have a mass of 20 kb or more.

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Genetic Analysis of Mitochondrial DNA from Korean Oysters, Crassostrea gigas (한국산 참굴(Crassostrea gigas) 미토콘드리아 DNA의 유전적 분석)

  • KIM Sang Hae;PARK Mi Seon;KIM Young Hun;PARK Doo Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.5
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    • pp.804-808
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    • 1997
  • The genetic differentiation and characteristics of two oyster populations (Crassostrea gigas) in Korea were assessed based on the restriction fragment length polymorphisms (RFLP) analysis and the restriction patterns of subcloned mtDNA. The restriction fragments of twenty individuals in West Sea revealed an identical pattern, determined by 8 restriction enzymes. On the other hand, two haplotypes having variation at the HindIII site were shown in the specimens from South Sea; minor haplotypes (4 of 20) were similar to the results obtained from individuals in West Sea while major haplotypes were different from those in West Sea. It was suggested that oysters (C. gigas) of West Sea might have been introduced to South Sea. Each mitochondrial DNA from two oyster populations in Korea and from one in Japan was divided to three parts and subcloned into pUC19 to use in genetic studies effectively. Restriction map was constructed based on the cleavage pattern by multiple restriction enzymes.

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Optimal Enrichment Temperature for Rotifer and Microalgae Selection for Cold-Water Species Culture (한해성 품종 종묘생산을 위한 로티퍼의 적정 영양강화 수온 및 미세조류 선택)

  • Park, Jin-Chul;Lee, Bae-Ik;Park, Heum-Gi;Kwon, O-Nam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.6
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    • pp.654-658
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    • 2010
  • The purpose of this study is to establish methods for enhancing the survival and growth of cold-water fish and crustacean larvae based on the nutritional components of zoo and phyto live foods. Rotifers, Brachionus rotundiformis, were cultured with a supplement of freshwater condensed Chlorella vulgaris at $28^{\circ}C$ and enriched with Algamac $2000^{(R)}$ at 16, 20 and $26^{\circ}C$, respectively. Isochrysis galbana, Chaetoceros calcitrans and Chlorella ellipsoidea were centrifuged for component analysis after being cultured for approximately one week with conway medium at $20^{\circ}C$. The crude protein and lipid contents of the rotifers were 58.4% and 10.9%, respectively, before enrichment. After enrichment at each temperature, total protein and essential amino acid contents were increased by reducing the enrichment temperature. However, unsaturated fatty acids and multiple fatty acid index (UI) showed their highest values at $20^{\circ}C$. Mono-unsaturated fatty acid content was highest (72.6%) at $16^{\circ}C$. The total protein contents of C. calcitrans and C. ellipsoidea were higher, 33.0% and 35.2%, respectively, than that of I. galbana, 27.8%. Methionin, leusine and histidine, essential amino acids of C. ellipsoidea, had considerably higher values, 50.2, 287.2 and 68.1 mg/g dry matter, respectively, compared to other microalgae. Total lipids, UI, DHA and n-3 PUFA of I. galbana had higher values, 23.6, 272.0, 12.9% and 45.2%, respectively, than other microalgae. Therefore, for cold-water fish and crustacean larvae that require high n-3 PUFA and DHA contents, enrichment of rotifers is desirable at $20^{\circ}C$. Fish larvae would also need more I. galbana than other microalgae.

An Analysis on the Measurement Items to Assess the Landscape Value of Agriculture and Fisheries Heritage (농어업유산의 경관가치를 측정하기 위한 평가항목 분석)

  • Choi, Woo-Young;Min, Byoung-Wook
    • Journal of Korean Society of Rural Planning
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    • v.20 no.4
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    • pp.89-99
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    • 2014
  • The purpose of this research is first, to define what measurement items in terms of subjective consideration and preference can be used to assess the landscape values of agriculture and fisheries heritage, and second, to understand the perceptive patterns particularly how landscape experts weigh up the importance of the each measurement item. In order to extract the measurement items, extensive literature review was performed including research documents as well as domestic and international policy reports. A survey targeting the experts was conducted to ask their opinions on the importance of the selected items. For the analysis, SPSS 20.0 for Windows was used to carry out reliability analysis, descriptive statistics such as arithmetic mean and frequency distribution, factor analysis, and multiple linear regression modeling. The results are: the importance value of the landscape values in agriculture and fisheries heritage was 4.1494; the ratio value that the experts perceived the importance was 87.2%; and the average of the importance value of the analyzed items was 3.71. All the items have more than 3.00. Ten factor groups were summarized and defined whose total explanation power was 67.86%. The factor groups were named as lyricism, authenticity, environmentally-friendliness, durability, recognizability, regionality, visibility, value of sightseeing, social image, and universality. The factors influencing the landscape values are, in order of importance, recognizability, authenticity, visibility, universality, durability, and nativeness. According to the analysis, however, environmentally-friendliness, regionality, value of sightseeing, and social image were not as important.

The Study on the Fisheries Biological Feature of Hairtail, Trichiurus lepturus from the Cheju Strait (제주해협에 출현하는 갈치 (Hairtail, Trichiurus lepturus)의 어업생물학적 특성)

  • KIM Sang Hyun;LEE Young Don;RHO Hong Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.1
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    • pp.17-25
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    • 1998
  • A fisheries biological study on the hairtail (Trichiurus lepturus LINNAEUS), which was collected from Cheju City, Hanrim, Sungsanpo and Seogwipo in Cheju Island, was carried out from June through December In 1992. GSI of the hairtail maintained relatively high from June to September, and then it began to decrease in October and remained low until December. The maturation and spawning period was between June and October, and the major spawning occurred in August. The hairtail turned out to be a multiple spawning species which spawn two or three times In a single spawning season. During the spawning season the number of females was greater than that of males, whereas the sex ratio was almost 1 : 1 during the rest of the season. Fecundity estimated from various sizes of the hairtail ranged from 12,821 to 125,876. The bigger the snout anal length and body weight of the hairtail was, the more eggs it possessed.

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Authentication Method using Multiple Biometric Information in FIDO Environment (FIDO 환경에서 다중 생체정보를 이용한 인증 방법)

  • Chae, Cheol-Joo;Cho, Han-Jin;Jung, Hyun Mi
    • Journal of Digital Convergence
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    • v.16 no.1
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    • pp.159-164
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    • 2018
  • Biometric information does not need to be stored separately, and there is no risk of loss and no theft. For this reason, it has been attracting attention as an alternative authentication means for existing authentication means such as passwords and authorized certificates. However, there may be a privacy problem due to leakage of personal information stored in the server. To overcome these weaknesses, FIDO solved the problem of leakage of personal information on the server by using biometric information stored on the user device and authenticating. In this paper, we propose a multiple biometric authentication method that can be used in FIDO environment. In order to utilize multiple biometric information, fingerprints and EEG signals can be generated and used in FIDO system. The proposed method can solve the problem due to limitations of existing 2-factor authentication system by authentication using multiple biometric information.

Propeller racing of ocean-going ships with multiple screw propellers (다축선의 프로펠러 레이싱 추정에 관한 연구)

  • Park, Jong-Heon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.43 no.3
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    • pp.222-231
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    • 2007
  • This paper represents a basic statistical examination on the navigability of ocean-going ship from the point of estimating the time lasting period when propeller racing occurred by using the basic probability theory and the statistics. The propeller racing is one of the most important seakeeping qualities in relation to the safety of the main engine and shafting system. The trend of the racing has been mainly investigated in order to estimate allowable maximum propeller diameter, operation of ocean-going ships, etc.. In those studies, the propeller racing generally and mainly means the situation (propeller exposed) in which the relative motion amplitude between ship hull and wave surface would exceed a depth of point in rotary disk propeller. Therefore, it seems that the magnitude of the amplitude and its exceeding frequency of propeller racing have been examined as a principal subject of study as usual. However, the time during which the amplitude exceeds the depth of point, that is, the propeller exposes in the air, must be also one of most important factor affecting the trend of propeller racing. Then, this paper proposes a new practical method for estimating the time lasting of exposed propeller related to propeller racing in rough-confused seas on the basis of the linear strip theory and the statistics. And, numerical examples of estimating the propeller racing probability are given for four wide ship forms. Finally the usefulness of the proposed method for predicting propeller racing based on the time lasting period is discussed.

The Mediated Effects of Emotion Regulation in the Relations between Maternal Parenting and Children's Adaptation to School Life of Elementary School Students (어머니의 양육행동이 초등학생의 학교생활적응에 미치는 영향 : 정서조절력 매개효과)

  • KIM, Du-Gyu;KANG, Mun-Suk
    • Journal of Fisheries and Marine Sciences Education
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    • v.29 no.2
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    • pp.365-379
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    • 2017
  • The purpose of this study was to test the mediated effects of emotional regulation in the relations between maternal parenting and children's adaptation to school life of elementary school students. Three-hundred Seven elementary school students completed the maternal parenting scale, the emotional regulation scale, and the adaptation to school life scale. In order to find to identify how maternal parenting, emotional regulation were related with their adaptation to school life, Pearson correlation coefficients were used in the computation. To examine the effects of maternal parenting, emotional regulation on adaptation to school life, multiple regression analyses were conducted. To examine whether emotional regulation as a mediating variable in the process that maternal parenting is influencing children's adaptation to school life, hierarchical regression analyses were performed. The results of this study were summarized as follows. First, the analysis of the relationship of maternal parenting, emotional regulation with adaptation to school life shows that there is a significant positive correlation between maternal parenting, emotional regulation and adaptation to school life. Second, in the multiple regression analysis with maternal parenting and emotional regulation as a predictor and adaptation to school life as an outcome variable it has been shown that the emotional regulation were significant in adaptation to school life, but maternal parenting were not significant in adaptation to school life. The higher the emotional regulation is the better can children adapt themselves to school life. Third, the analysis on the mediating effects of emotional regulation in the relationship of maternal parenting and adaptation to school life showed that emotional regulation full mediates the relationship of maternal parenting with adaptation to school life.

Variations of SST around Korea Inferred from NOAA AVHRR Data

  • Kang, Yong-Q.;Hahn, Sang-Bok;Suh, Young-Sang;Park, Sung-Joo
    • Korean Journal of Remote Sensing
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    • v.17 no.2
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    • pp.183-188
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    • 2001
  • The NOAA AVHRR remotely sensed SST data, collected by the National Fisheries Research and Development Institute (NFRDI), are analyzed in order to understand the spatial and temporal distributions of SST in the sea near korea. Our study is based on 10-day SST images during last 7 years (1991-1997). For a time series analysis of multiple SST images, all of images must be consistent exactly at the same position by adjusting the scales and positions of each SST image. We devised an algorithm which automatically detects cloud pixels from multiple SST images. The cloud detection algorithm is based on a physical constraint that SST anomalies in the ocean do not exceed certain limits (we used $\pm$3$^{\circ}C$ as a criterion of SST anomalies). The remotely sensed SST data are tuned by comparing remotely sensed data with observed SST at coastal stations. Seasonal variations of SST are studied by harmonic fit of SST normals at each pixel and the SST anomalies are studied by statistical method. It was found that the SST anomalies are rather persistent for one or two months. Utilizing the persistency of SST anomalies, we devised an algorithm for a prediction of future SST. In the Markov lprocess model of SST anomalies, autoregression coefficients of SST anomalies during a time elapse of 10 days are between 0.5 and 0.7. The developed algorithm with automatic cloud pixel detection and rediction of future SST is expected to be incorporated to the operational real time service of SST around Korea.