• Journal of Korean Port Research
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• v.1 no.1
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• pp.21-47
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• 1987

Nowaday all the countries of the world have studied the various problems caused in operating their own ports efficiently. Ship delay in the port is attributal to the inefficient operation in the navigation aids, the cargo handling, the storage and transfer facilities, and to the inefficient allocation of gangs or to a bad service for ships. Among these elements the allocation of gangs is the predominating factor in minimizing ship's turn round time. At present, in the case of Pusan Port. the labour union and stevedoring companies allocate gangs in every hatches of ships by a rule of thumb, just placing emphasis on minimizing ship's turn round time, without applying the principle of allocation during the cargo handling. Owing to this the efficiency of the cargo handling could not be expected to be maximized and this unsystematic operation result in supplying human resources of much unnecessary surplus gangs. Therefore in this paper the optimal size and allocation of gangs for minimizing the ship's turn round time is studied and formularized. For the determination of the priority for allocation the evaluation function, namely $F=PHi^{n}{\times}(W+H)$, can be obtained; where, PHI : Principal Hatch Index W : Total Cargo Weight represented in Gang-Shifts H : Total Number of Ship's hatches and also for the optimal size of gangs the average number of gang allocated per shift (Ng), namely Ng=W/PHI, is used. The proposed algorithm is applied to Pusan Port and its validity is verified.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.676-683
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• 2023

The development of the egg, larvae, and juveniles of Acheilognathus macropterus from the Wicheon stream of Nakdonggang River was investigated for early life history characteristics. The fish used in the study were collected from Wicheon stream located in Bian-myeon, Uiseong-gun, Gyeongsangbuk-do. The fertilized egg was 1.88±0.09 mm (n=30) in long diameter and 1.34±0.06 mm (n=30) in short diameter. After fertilization at a water temperature of 20℃, the egg took 31 h and 40 min to hatch. Newly hatched larvae had an average total length of 3.92±0.13 mm (n=30) and possessed a yolk sac the mouth and anus were not developed. Twenty days after hatching, the postflexion larvae had an average total length of 8.08±0.29 mm (n=30), with the tail tip fully bent at 45° and began feeding. Thirty-three days after hatching, the number of fin stems reached an integer with an average total length of 15.0±1.08 mm (n=30). In this study, differences in the egg size, hatching time, melanophore development period, and distribution location were confirmed between A. macropterus and allied species.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_3
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• pp.1305-1314
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• 2023

The global ship repair and modification market is expected to grow up to approximately $ 30 billion by 2025. Korea's shipbuilding industry is leading the world grounded on its international competitiveness in design and production technology. The reality, however, is that the ship repair and modification industry is centered on Gyeongnam, and there are only two to three ship repair workplaces that can repair large ships. Therefore, domestic ship repair companies target small and medium-sized ships mainly. This is because there are few workplaces equipped with a large dock in which large ships like LNG ships can be inspected regularly or repaired, complaints are severe for environmental problems, and related environmental regulations are so strict that it is very hard to obtain government approval for the extension of ship repair and modification workplaces or the opening of new shipbuilding sites. Besides, on account of the workers' high wages, few experts related, and higher ship repair price compared to that of Southeast Asia, most of the volume of repairing large ships including domestic LNG ships is being lost to Southeast Asian or Chinese markets. In this study, the work process and pre-work preparation process for ship hull (winch, windlass, hatch cover, ramp door, cargo gear, anchor chain) repair were analyzed and presented to foster domestic ship repair experts and revitalize related industries.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.388-393
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• 2023

This study evaluated the in vitro nematicidal activity of Glycyrrhiza uralensis root extracts (GuRE) on Meloidogyne incognita eggs and juveniles. The results showed that treatment of M. incognita eggs with 2.0 mg/mL GuRE for 5 and 10 d resulted in 64.0 and 68.1% hatch inhibition, respectively. Furthermore, the relative mortality of J2 was 96.2% after treatment with 2.0 mg/mL GuRE for 48 h. Changes in the shape of the eggs and juveniles were determined after incubation with 2.0 mg/mL GuRE for 5 d and 48 h, respectively. These preliminary results suggest that GuRE can be used as an environment-friendly bio-nematicide to control root-knot nematodes. In the future, in vivo assays should be conducted using GuRE to ascertain its potential for widespread application as a nematicide.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.147-152
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• 2004

In Sequence Batch Reactor (SBR), the removal efficiencies if nutrient materials such as nitrogen and phosphate depend highly on quantity and quality of organic carbon source. Food waste thai contains abundant organic materials has been produced in ship. The applicability if anaerobically fermented if food waste (AFFW) as an external carbon source was examined in the lab-scale SBR process operated at $25^{\circ}C$. With the addition if AFFW increased, average removal efficiencies if $COD_cr$, T-N, T-P changed to $98.5\%,\;95\%,\;93\%$, respectively. Denitrification rate is 0.30g $NO_3-N/g\;VSS{\cdot}day$. In summary, it was suggested tint AFFW sould be used as an economical and effective carbon source for the biological nitrogen and phosphate removal.

• Korean Journal of Ichthyology
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• v.26 no.1
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• pp.17-24
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• 2014

The egg development and early life history of Acheilognathus majusculus which is Korean endemic species from Yeong river were observed under the controlled water temperature, $18.0{\pm}1.0^{\circ}C$. Fertilized eggs are opaque yellow in color and round oval shaped measuring 2.12 (2.08~2.18) mm in length and 1.86 (1.80~1.98) mm in breadth. The number of eggs averaged 72 (40~112) per an oviposition. The eggs of this species began to hatch about forty three hours after insemination and the total length of larvae was 4.23 mm mean. S form moving of larvae were not observed during larval development. The larvae reached at the heterotrophic stage about twenty-five days after hatching. It is estimated that the larvae was comming out from freshwater bivalve since that time in nature. A. majusculus was grew up to be adult stage enough which can be join to new production for three hundred days after hatching with over 67.8 mm in total length.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.1
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• pp.19-24
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• 2007

Covariance components and genetic parameters of weekly live body weight from hatching to six weeks of age and age of sexual maturation were estimated in a laying type Japanese quail line. The univariate and bivariate animal model analysis included hatching group and sex as fixed effects. Each trait was analysed with animal as random effect to fit the additive direct effect. Additional random effects incorporated in the models were changed according to the trait examined. The best model for a trait was chosen based on a likelihood ratio test, comparing the models with and without maternal additive genetic and maternal permanent environmental effects. Heritability estimates of live-weight at hatch and one to six weeks of age with their standard errors were 0.22${\pm}$0.088, 0.39${\pm}$0.099, 0.31${\pm}$0.086, 0.38${\pm}$0.056, 0.46${\pm}$0.055, 0.50${\pm}$0.059, and 0.56${\pm}$0.062, respectively. Direct heritability value of age of sexual maturation was moderate (0.24${\pm}$0.055). The variances due to permanent environmental effect of dam after one week of age and maternal genetic effect after two weeks of age were not important sources of variation. The correlations between direct and maternal genetic effects were negative and ranged from high to moderate values (-0.21 to -0.83). Among the weekly live weights, genetic correlations were generally high between not only successive but also early and late weightings. It suggests that selection for final weight may be based on early weight records. Genetic correlations between age of sexual maturation and live weights were low, favourable but had high standard errors. These results indicate that selection for high weight will potentially result in lower age of sexual maturation only with accurate determination of breeding values.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.10
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• pp.1471-1478
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• 2015

The present study aimed to assess the effect of dietary substitution of soybean meal (SBM) with dehulled-micronized faba bean (Vicia faba var. minor) in guinea fowl broilers on their growth traits, carcass quality, and meat fatty acids composition. In this trial, 120 day-old guinea fowl keets were randomly assigned to two treatments which were fed from hatch to 12 weeks of age. Birds were fed two wheat middlings-based diets comprising of a control treatment which contained SBM (78.3 g/kg) and a test diet containing dehulled-micronized faba bean (130 g/kg) as the main protein source. Substituting SBM with faba bean had no adverse effect on growth traits, dressing percentage, or breast and thigh muscles relative weight of the guinea fowls. Conversely, a decrease (p<0.05) of abdominal fat was found in guinea fowls fed the faba bean-diet. Breast muscle of birds fed faba bean had higher $L^*$ score (p<0.05) and water-holding capacity (p<0.05) than the SBM control diet. Meat from guinea fowls fed faba bean had less total lipids (p<0.05) and cholesterol (p<0.01), and higher concentrations of phospholipids (p<0.01). Feeding faba bean increased polyunsaturated fatty acid concentrations in breast meat and decreased the saturated fatty acid levels. Moreover, dietary faba bean improved the atherogenic and thrombogenic indexes in guinea fowl breast meat. Results indicated that substitution of SBM with faba bean meal in guinea fowl diet can improve carcass qualitative traits, enhancing also meat lipid profile without negatively affecting growth performance.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1593-1599
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• 2014

This study consisted of two experiments, conducted to assess the impact of phase at which vegetable protein (VP) diets are introduced to broiler chicks, and preference of birds for diets based on soybean or canola meal (CM). Two hundred and ten day-old Cobb 500 chicks were randomly distributed into five dietary groups in the main experiment. One group was fed on animal protein (AP) diet all through to 21 days of age; two other groups were started on AP diet for 7 days and then switched to diets containing soybean meal (AP-SBM) or AP-CM, while two other diets (SBM-AP and CM-AP) were started on one of the VP diets for 7 days and then switched to AP diet. A sub-experiment on thirty birds raised on a commercial diet to 7 days was used in a feed selection test to quantify the preference of birds for the diets containing mainly CM or SBM. Chicks were reared under similar care and management conditions and the diets were iso-caloric and iso-nitrogenous. Results of the main experiment showed that chicks on CM-AP diet ate more (p<0.05) than those on the other diets up to day 7. Body weight gain was highest (p<0.001) on the AP-SBM diet while birds on the CM-AP diet weighed the least at 7 d. Feed intake, body weight gain, feed conversion ratio, mortality, bone growth, visceral organ development, and activities of digestive enzymes were similar between the groups from hatch to 21 days of age. Results of the second sub-experiment showed that chicks preferred the CM-based diets to the SBM-based diets at 8 to 14 d (p<0.001) and 15 to 21 d (p<0.01) when given a choice. Overall, the birds were not affected by the nature of the starter diet although they tended to prefer the canola to soybean diets.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.643-649
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• 2018

Objective: POU class 1 homeobox 1 (POU1F1) mediates growth hormone expression and activity by altering transcription, eventually resulting in growth rate variations. Therefore, we aimed to identify chicken POU1F1 polymorphisms and evaluate the association between single nucleotide polymorphisms (SNPs) and growth-related traits, and logistic growth curve parameter traits (${\alpha}$, ${\beta}$, and ${\gamma}$). Methods: Three SNPs (M_1 to M_3) were used to genotype 585 $F_1$ and 88 $F_0$ birds from five Korean native chicken lines using a polymerase chain reaction-restriction fragment length polymorphism method. Results: Single marker analyses and traits association analyses showed that M_2 was significantly associated with body weight at two weeks, weight gain from hatch to 2 weeks, and weight gain from 16 to 18 weeks (p<0.05). M_3 was significantly associated with weight gain from 14 to 16 weeks and from 16 to 18 weeks, and asymptotic body weight (${\alpha}$) (p<0.05). No traits were associated with M_1. The POU1F1 haplogroups were significantly associated with weight gain from 14 to 16 weeks (p = 0.020). Linkage disequilibrium test and Haploview analysis shown one main haploblock between M_2 and M_3 SNP. Conclusion: Thus, POU1F1 significantly affects the growth of Korean native chickens and their growth curve traits.