• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.311-315
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• 2015

Euryalid specimens were collected from Gonghyeonjin and Daejin, Gangwon-do in the East Sea, Korea at a depth of 250-300 m by fishing nets on November 2013 and August 2014. They were identified as Gorgonocephalus arcticus Leach, 1819 belonging to family Gorgonocephalidae of order Euryalida, which was new to the Korean fauna. Nucleotide sequences of partial mitochondrial cytochrome c oxidase I (mt-COI) gene, which was 569 bp in length, were compared among four Gorgonocephalus species, and were subsequently employed to reconstruct phylogenetic trees using the MP, ML, and BI methods. As a result, no sequence difference was found between the G. arcticus mt-COI gene sequences from Korea and Canada, and the two made a strong monophyletic group. With the newly recorded G. arcticus in Korea, in total, four Gorgonocephalus species have been reported in Korea.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.69.2-69
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• 2001

This paper presents a new approach to the design of neural control system using digital signal processors in order to improve the precision and robustness. Robotic manipulators have become increasingly important in the field of flexible automation. High speed and high-precision trajectory tracking are indispensable capabilities for their versatile application. The need to meet demanding control requirement in increasingly complex dynamical control systems under significant uncertainties, leads toward design of intelligent manipulation robots. The TMS320C31 is used in implementing real time neural control to provide an enhanced motion control for robotic manipulators. In this control scheme, the networks introduced are neural nets with dynamic neurons, whose dynamics are distributed over all the network nodes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.94-101
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• 2015

The heat treatment machine based on immersion was developed to reduce temperature difference during netting process and appraised it performance compared current heat treatment machine using high pressure. It was also reviewed the optimum heat treatment procedures for PBSAT monofilament net in accordance with the immersion time and temperature. The procedure was based on physical measurement such as breaking load, elongation and angle of the mesh for PBSAT monofilament. The water temperature gap of the treatment machine based on immersion was less than $1^{\circ}C$. and the energy consumption was also increased in high temperature condition. It was identified that the optimum temperature was $75^{\circ}C$ and its optimum processing time was between 15 minutes and 20 minutes to get qualified physical properties.

• Journal of Bio-Environment Control
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• v.28 no.2
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• pp.150-157
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• 2019

This study was carried out to investigate at the micrometeorology change of the orchard according to the net installation. Two weather stations were installed at the inside of the anti-insect nets(2 mm, 4 mm), one was installed at the outside(control). They were observed the temperature, humidity, wind speed and solar radiation from April to September 2018. Daily mean temperature at the experimental group was higher than control group by $0.2^{\circ}C$. Daily mean humidity at the experimental group was higher than control group by 3.5 to 4.7%. Daily mean the solar radiation at the experimental group(2 mm) was lower than control group by 50%. The wind speed was decreased from 12% to 50% of the external wind speed at 4 mm, and from 25% to 59% at 2 mm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.1
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• pp.67-73
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• 1998

In order to find out the environmental factors influencing the catch of anchovy lift nets in kamakbay, the three oceanographic factors, i. e., the water temperature, the salinity, the amount of chlorophyll-a were observed respectively from August 1 to 12, 1995 and from September 20 to 26, 1995, and each of them was compared with the catch of anchovy by the lift net. The results obtained are summerized as follow : 1) The water temperature was ranged from 17.3 to 29.6$^{\circ}C$ and its difference between the surface and bottom was 1 to 3$^{\circ}C$. In the three areas, A, B and C, the area A was the hightest in temperature, the area B being a second, and the area C being the lowest. 2) The salinity was ranged from 32.20 to 33.47$\textperthousand$ and its difference between the surface and bottom was not significant. In the three areas, the area A was the highest in salinity, the area B being a second, and the area C being the lowest. 3) The amount of chlorophyll-a was ranged from 0.19 to 5.30mg/m supper(3) and its difference among the three areas was not significant. Daily variation of the amount was very irregulated because the position operated was changed daily. 4) A comparison of the water temperature, the salinity and the amount of chlorophyll-a with the catch gave that the water temperature and the amount of chlorophyll-a had large influence on the catch and the salinity did not so. However, the influence of the amount of chlorophyll-a was larger than that of the water temperature. 5) The catch of anchovy was large respectively during two hours after sun set and during two hours before sun rise.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.1
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• pp.43-49
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• 2015

By the trends of electronic package to be smaller, thinner and more integrative, organic printed circuit board is required to be finer Cu trace pitch. This paper reports on a study of failure mechanism for PCB with fine Cu trace pitch using biased HAST. In weibull analysis of the biased HAST lifetime, it is found that the acceleration factor (AF) of between $135^{\circ}C/90%RH/3.3V$ and $130^{\circ}C/85%RH/3.3V$ is 2.079. A focused ion beam (FIB) was used to polish the cross sections to reveal details of the microstructure of the failure mode. It is found that $Cu_xO/Cu(OH)_2$ colloids and Cu dendrites were formed at anode (+) and at cathode (-), respectively. Thus, this gives the evidence that Cu dendrites formed at cathode by $Cu^{2+}$ ion migration lead to a short failure between a pair of Cu nets.

• Journal of Aquaculture
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• v.20 no.4
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• pp.260-264
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• 2007

We investigated egg collection and the effects of water temperature (4, 7, 10, 13 and $16^{\circ}C$) on egg development, hatching and larval growth of Pacific cod Gadus macrocephalus under laboratory conditions. Fertilized eggs were round in shape ($1.01{\pm}0.03\;cm$) and adhesive to nylon nets. Fertilization rate was 68% by wet method. The time of egg development was negatively proportional to water temperature with the range of $4^{\circ}C$ to $13^{\circ}C$. Eggs hatched only at $7^{\circ}C$ after 288 hours of fertilization and $10^{\circ}C$ after 192 hours. Hatching rate was highest as 65% at $7^{\circ}C$ followed by $34.4^{\circ}C$ at $10^{\circ}C$. Survival rate was 18.3% at $7^{\circ}C$ and 5.2% at $10^{\circ}C$.

• Food Science and Preservation
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• v.15 no.6
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• pp.847-851
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• 2008

The handling and processing of agricultural products in Korea is done manually. Small plastic boxes, nets, and corrugated cardboard boxes are used as containers during harvesting, sorting and other product handling operations. However, these practices are labor-intensive, time-consuming, require various kinds of packing materials, and are expensive because of high operating costs. To overcome these problems, the use of pallet bins with pre-cooling and storage features for handling and processing bulk farm products was investigated. The airflow resistances through bulk potato, onion and mandarin stocks were measured, and the pallet bins and a pressure pre-cooling device were manufactured. The opening ratio, bed depth and airflow rate through bulk potato, onion and mandarin in the pallet bin were defined with regression equations. The cooling rates of bulk potato, onion and mandarin were 0.8C/h ($21.7{\rightarrow}0C$, 14.5 h), 0.4C/h ($15.4{\rightarrow}.0C$, 32.2 h) and 0.7C/h ($13.7{\rightarrow}C$, 18.8 h), respectively, with the pressure pre-cooling system. Temperature deviances for storage of bulk potato, onion and mandarin were 0.12C, 0.12C and 0.17C, respectively.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.183-188
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• 1995

This experiment was carried out to clarity the effect of summer softening cultivation on bud yield of Aralia continentalis Kita. Bulbous plant harvested on March 25 and stored in low temperature storage room($0-2^{\circ}C$) were transplanted in May, June, July and August. The bulbous plants were grown under black PE film and 50%(T-2250) silver shading nets. The results obtained are summerized as fallows. Harvesting time in Jul. and Aug. transplanting was 15days and was speeling 5days in May transplanting. The accumulative temperature of whole growth period was about $400^{\circ}C$. But yield of soft stems in June transplanting was 6.64(ton/ha), which was more than others. High temperature induced low-quality of soft stem in transplanting in July. Net income was 18000(1000won/ha) in transplanting in May or June.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.3
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• pp.228-239
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• 2017

This study investigated the drag coefficient and lift coefficient of thirteen kinds of knotless nettings used for large purse seine gear. By comparing the hydrodynamic characteristics with nets of the previous study, the characteristics of this study were derived as a purse seine gear. Thirteen kinds of nettings with different length of bar (l) and diameter (d) were used in the experiment, out of which six kinds used the 30 mm in mesh size and three kinds with 40 mm. The drag coefficient ($C_d$) also increased with increasing d/l. It can be expressed as $C_d=3.71499(d/l)+0.76595$ at a current speed 0.4 m/s and $C_d=4.30324(d/l)+0.69056$ at a current speed 0.5 m/s. Compared with previous studies, drag coefficient values were similar to knotless net of similar d/l and smaller than drag coefficient of knot net. Therefore, using knotless net in a purse seine has the advantage of reducing the resistance acting on the purse seine gear.