• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.544-545
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• 2012

본 논문에서는 3상 4선식 UPS 인버터에 대한 저항성 수하 제어 방식 병렬운전 알고리즘을 제안하고, PSIM 시뮬레이션을 통해서 제안된 병렬운전 알고리즘과 강인 전압제어기를 적용한 2병렬 UPS 인버터의 운전 결과를 제시한다. 3상 UPS 인버터 2대로 병렬운전 환경을 구축하였고, 주파수-전압 강하 방식의 저항성 수하 제어를 이용하여 저항 부하, 유도성 부하, 비선형 부하에 대한 전력분담을 확인하였다.

• Korea Trade Review
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• v.48 no.4
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• pp.149-168
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• 2023

Through an examination and analysis of straight bills of lading and sea waybills in the context of English, U.S.A and Korean law, and relevant international conventions on maritime transport, the following results were obtained: Prior to the enactment of U.K.'s the Carriage of Goods by Sea Act in 1992, straight bills of lading had functional differences between countries. However, after the enactment of this law, negotiable bills of lading obtained the same legal status and functionality in both Korea and the United States, as well as in the UK. As for sea waybills, all three countries treated them with the same contractual and legal status. In other words, they serve as receipts for the transported goods and act as evidence of the maritime transportation contract. Nevertheless, they are non-negotiable, and the delivery of goods can be made to the consignee or their agent based on their identity. However, the transfer of ownership rights over the goods or acquisition of legal rights against the carrier cannot be achieved through the transfer or endorsement of Sea Waybills.

• Journal of Aquaculture
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• v.3 no.1
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• pp.49-63
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• 1990

A population ecological study was carried out to estimate survival and growth rates, biomass, biological production and turnover ratio of cultured sea squirt, Halocynthia roretzi, by growth stages, using data from in situ culture experiment off Hansando in the southern part of Korea from February 1985 to July 1986. The squirt population followed an exponential decay function and the instantaneous coefficient of total mortality (Z) was estimated to be 0.0614 $month^{-1}$(Var (Z) = 0.000126). Growths in total weight and meat weight of squirts were expressed as linear functions during the period of culture experiment. The growth of squirts showed a negative correlation with the water temperature. The mean biomass per string ranged from 2.14 kg for March of the first year to 16.26 kg for March of the next year. The biological production per string was estimated to range from 3.28 kg for the first summer (June - July) to 6.46kg for the first late winter (February-March). The peak of turnover ratio occurred in the late winter (February-March) as 3.013 and the ratios sharply declined thereafter. Based on the results of this study, management implications for culturing sea squirts were also suggested. The optimum harvest time ($t_{mb}$) when the peak biomass in terms of total weight occurred was estimated to be late June of the second year, which corresponded to 16.7 months after the main hanging. However, the time when the peak biomass in terms of meat weight was occurred was early July of the second year. The maximum harvest biomass was 17.4 kg per string in terms of total weight and 6.3 kg per string in terms of meat weight. In conclusion, the process of culture should be conducted on the basis of the knowledge of population ecological theories as shown in this study.

• Journal of Aquaculture
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• v.15 no.3
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• pp.145-155
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• 2002

Effect of density (30, 40, 65, 90 or 120/cage) of lantern and bottom cages on growth of the ark shell, Scapharca satowi was studied in the Korean west coast from April 2000 to October 2001, when the following range of environmental conditions prevailed : temperature : 4.2 -25.5 $^{\circ}C, salinity : 30.23-32.$15\textperthousand, dissolved oxygen : 5.12-7.16 $ml$/l, pH : 7.84-8.17, phosphate : 0.22-0.56 $\mu $M, dissolved inorganic nitrogen : 3.16-9.10 $\mu $M, suspended solid : 7.6-17.9 mg/l, chemical oxygen demand: 0.46-1.61 mg/l and chlorophyll-a : 0.92-5.93 $\mug/l. Daily growth rate of shell length ranged from 0.066 to 0.071 mm/day for the lantern net cages, and from 0.079 to 0.082 mm/day for the bottom cages. Total weight also ranged from 0.067 to 0.082 g/day in the lantern net cages, as against 0.099 to 0.114 g/day in the bottom cages. Hemoglobin content of S. satowi (55 mm shell length), which was about 3.9 g/dl during february, 2001, increased to 6.0 and 7.0 g/dl during October, 2001 in animals culture in the lantern and bottom cages, respectively. ANOVA test of the growth rate showed that the growth rate of S. satowi, was significantly dependent on rearing density and the tested culture methods (P < 0.0001). The daily growth rate of the shell length was more significantly correlated with water temperature; the growth rate of shell length and total weight showed a tendency decrease with decreasing temperature. In cages suspended at the bottom, not only the increase shell weight but also the meat obtainable from comparable sized S. satowi was greater. Survival decreased with increasing density and was optimal at the density of 30 individual/cage.

• Journal of Korean Society of Forest Science
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• v.110 no.1
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• pp.43-52
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• 2021

In this study, carbon (C) and nitrogen (N) inputs by the litterfall of Japanese cypress (Chamaecyparis obtusa Endlicher) planted in pine wilt disease-disturbed forests were determined. The study sites were located in Sacheon-si, Gyeongsangnam-do. Eight plots under two regeneration sites (DR: four plots of C. obtusa planted under slightly disturbed Pinus thunbergii stands; CR: four plots of C. obtusa planted following the clear-cutting of severely disturbed pine stands) were established to collect litterfall from December 2018 to December 2019. The growth of diameter at breast height (DBH) was significantly higher in the CR treatment (12.10 cm) than that in the DR treatment (9.42 cm). C and N concentrations and the C/N ratio in C. obtusa leaf litter did not differ significantly between the two regeneration treatments, but the C/N ratio was significantly lower in the leaf litter collected in October (93) relative to that collected in December (143). The C concentration of litterfall components was significantly higher in C. obtusa leaf litter and in P. thunbergii needle litter than in broadleaved and miscellaneous litter, whereas the N concentration in broadleaved and miscellaneous litter was significantly higher than that in the leaf litter of C. obtusa and in branch litter. Thus, the C/N ratio was significantly higher in C. obtusa leaf litter and branch litter compared with that in miscellaneous and broadleaved litter. Respective C and N inputs by leaf litter were 773 kg C ha-1 yr-1 and 6.95 kg N ha-1 yr-1 for the CR treatments, and 78 kg C ha-1 yr-1 and 0.70 kg N ha-1 yr-1 for the DR treatment. Total C and N inputs were higher for the DR treatment (3,765 kg C ha-1 yr-1 and 47.6 kg N ha-1 yr-1, respectively) than for the CR treatment (1,290 kg C ha-1 yr-1 and 17.2 kg N ha-1 yr-1, respectively). These results indicate that, for C. obtusa, the DBH growth in the CR treatment was superior to that in the DR treatment, but the C and N inputs by litterfall were considerably reduced in CR treatments.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1995.10a
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• pp.205-208
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• 1995

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.123-124
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• 2003

• The Journal of the Korean dental association
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• v.17 no.12 s.127
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• pp.881-884
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• 1979

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.97-98
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• 2005

• The Journal of the Korean dental association
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• v.16 no.9 s.112
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• pp.645-649
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• 1978