• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.124-125
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• 2005

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2941-2951
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• 2018

The purpose of this paper is to analyse the effect of ocean weather factors on shipments of swimming crab. We use the data of data portal and ocean weather factors (mean wind velocity, mean atmospheric pressure, mean relative humidity, mean air temperature, mean water temperature, mean maximum wave height, mean significant wave height, maximum significant wave height, maximum wave height, mean wave period, maximum wave period). We did statistical analysis using Poisson regression analysis and negative binomial regression analysis. As the result of study, important factors influential in the shipments of swimming crab turn out to be mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature, maximum wave height, mean wave period and maximum wave period. the shipments of swimming crab increases as mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature increases or mean wave period increase. However, as maximum wave height, maximum wave period decreases, the shipment of swimming crab increases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.369-379
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• 1993

Using a successive removal approach the mechanism of sampling capture efficiency of blue crabs by dredges was studied in Chesapeake Bay during winter 1992. For the twenty-six field experiments no significant statistical differences were detected in dredge efficiency using general linear model analysis by factors including bottom sediments, water depths, and sampling vessels. Dredge efficiency (i.e., catchability) was estimated by two methods, Leslie (Leslie and Davis, 1939) and a simple revised method. Mean catchability was estimated at 0.26 (SE=0.03), indicating that only $26\%$($95\%\;C. I.=20{\sim}32\%$) of crabs present in the path of the dredge of a given sampling area are caught with a single dredge tow. Dredge efficiency declined exponentially as crab density increased.

• Development and Reproduction
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• v.10 no.1
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• pp.19-32
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• 2006

Genomic DNA isolated from two species of Korean freshwater crab(Eriocheir sinensis) and swimming crab(Portunus trituberculatus) was amplified several times by PCR reactions. The seven arbitrarily selected primers OPA-05, OPA-13, OPA-16, OPB-06, OPB-15, OPB-17 and OPD-10 were used to generate the identical, polymorphic, and specific fragments. 505 fragments were identified in the freshwater crab species, and 513 in the swimming crab from Buan: 81 specific fragments(16.0%) in the freshwater crab species and 100(19.5%) in the swimming crab. 165 identical fragments, with an average of 23.6 per primer, were observed in the freshwater crab species. 66 fragments, with an average of 9.4 per primer, were identified in the swimming crab species. The numbers of polymorphic fragments in the freshwater crab and swimming crab were 50 and 14, respectively. The oligonucleotides decamer primer OPB-17 generated identical DNA fragments, approximately 300 bp, in both the freshwater crab and swimming crab species. Compared separately, the average genetic difference was higher in the swimming crab than in the freshwater crab species. The average genetic difference was $0.726{\pm}0.004$ between the freshwater crab and swimming crab species. The dendrogram obtained by the seven primers indicates four genetic clusters: cluster 1(FRESHWATER 01), cluster 2(FRESHWATER 02, 03, 04, 05 and 06), cluster 3(FRESHWATER 07, 08, 09, 10 and 11), and cluster 4(SWIMMING 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 and 22). The shortest genetic distance displaying significant molecular difference was between individuals SWIMMING no. 18 and SWIMMING no. 17 from swimming crab(0.096). Ultimately, individual no. 02 of the freshwater crab was most distantly related to freshwater crab no. 03(genetic distance = 0.770). As stated above, the potential of RAPD-PCR to identify diagnostic markers for the identification of two crab species has been demonstrated.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.549-556
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• 1995

Experiments were carried out to examine the combined effects of hypoxia and hydrogen sulfide on survival, feeding activity and metabolic rata or Blue crab, Portunus trituberculatus. Survival rate of the crab was significantly affected by $\leq2.14mg/l$ dissolved oxygen, and feeding activity was also reduced below 1.41mg/l dissolved oxygen. Metabolic rate of the crab exosed to hypoxia $(\leq3.35mg/l)$ was significantly reduced than that exposed to normoxia. The combined effects of hypoxia $(\leq1.86mg/l)$ and hydrogen sulfide $(12.35 {\mu}g/l)$ on the survival rate were highly toxic than each single effect. Feeding activity was also decreased by the combinedexposure to $\leq1.86mg/l$ dissolved oxygen and $(12.35 {\mu}g/l)$ hydrogen sulfide compared with single effect.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.367-377
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• 2018

Swimming crab(Ovalipes punctatus) is produced in Korea and utilized as semi-processed food at streamed cooked state. Recently, protein hydrolysates have been known as having function such as antioxidant, suppression of hypertension, immunodulatory, alleviation of pain, and antimicrobial activity. This research was investigated to find the functional antioxidant from crab hydrolysates. To fine optimal protease enzyme, alcalase, bromelain, flavourzyme, neutrase, papain, and protamex were selected to evaluate the DPPH radical scavenging activity and finally bromelain to show the best activity was selected. The molecular weight of bromelain hydrolysates were distributed with range from 500 to 3,200 Da and 7 different molecules or more. The amino acids related to antioxidant capacity was about 42.54%. The processes optimization study used was the response surface methodology. The ranges of processes were the reaction temperature of 40 to $60^{\circ}C$, pH 6 to 8, and enzyme concentration 1 to 3%(w/v). As a result, the optimization of process was determined at temperature of $55^{\circ}C$, pH of 6.5, and enzyme concentration of 3%(w/v). In these conditions, degree of hydrolysates were maximum 71.60%. Therefore, we expect that those products are useful as functional food ingredients.

• 어항어장
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• s.103
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• pp.12-16
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• 2013

• Monthly Newsletter
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• no.199
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• pp.3-3
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• 2004

• Monthly Newsletter
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• no.200
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• pp.2-2
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• 2004

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.310-314
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• 1990

In order to find out the most favorable shape and structure of pot for crab, Charybdis japonica Edwards, the common box type and cylinder type of net pots with two entrances, and the modified cone type and box type of net ones with four were prepared respectively. Then, the ability of the above pots attracting the crab into them and their catches were investigated through tank and field experiments. The attracting ability was higher in pots with four entrances than those with two. In case of two entrance pots, the ability was a little higher in the cylinder type than in the box type. But in four entrance pots, the box type yielded a little higher ability than the cone type. The catches were also arranged by the pots in almost same order with the attracting ability. But, it was only added to the arrangement that the cone type with four entrances had no significant difference of catch with the cylinder type with two entrances. Thus, the most favorable pot for the crab was concluded to be the box type with four entrances.