• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1282-1288
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• 2010

This paper proposes a novel microstrip patch antenna to make impedance matching possible by using slot/T-slot capacitive coupling between the patch and 50 $\Omega$ feed line on a ground plane. The single band/linear polarization patch antenna shows linear polarization at 2.4 GHz band. Under -10 dB return loss, the single band/linear polarization patch antenna obtains 50 MHz bandwidth at 2.37 GHz~2.42 GHz. The dual band/dual polarization microstrip patch antenna shows circular polarization at 2.4 GHz band and linear polarization at 3.1 GHz band. Under -10 dB return loss, The dual band/dual polarization microstrip patch antenna obtains 340 MHz bandwidth at 2.23~2.57 GHz and 375 MHz bandwidth at 2.95~3.325 GHz.

• Progress in Superconductivity and Cryogenics
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• v.10 no.4
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• pp.38-42
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• 2008

Miniature J-T cryocooler using nitrogen or argon has been widely adopted in cooling infrared sensor for space/military application and cryosurgery. Argon or nitrogen, however, has relatively low specific cooling power compared to nitrous oxide, but the ultimate operating temperature is much lower than nitrous oxide. On the other hand, nitrous oxide has large specific cooling power, but the operating temperature is limited to its boiling point (>183K). To compromise the different characteristics of these gases, the performance of miniature J-T cryocooler using argon and nitrous oxide mixture is investigated in this paper. Three different compositions of mixture (25/75, 50/50, and 75/25 molar fraction) are blended and tested. The results are compared with the experiments of pure argon and pure nitrous oxide. The experimental results show some encouraging potentiality of mixed refrigerant J-T cryocooler. The critical clogging problem, however, was observed with argon and nitrous oxide mixture, and the lowest achievable temperature with this mixture was limited to the freezing point of nitrous oxide. The paper discusses detailed clogging process of the mixture and suggests an alternative.

• Korean Journal of Poultry Science
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• v.41 no.2
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• pp.77-85
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• 2014

This study was conducted to investigate the effect of duck and pork meat mixing ratio on quality characteristics of emulsion type sausage at $4^{\circ}C$ during 5 weeks. Treatments on the basis of the meat content were subjected to 100% duck meat (T1), 100% pork meat (T2), 50% duck meat + 50% pork meat (T3), 40% duck meat + 60% pork meat (T4), and 30% duck meat + 70% pork meat (T5). The moisture content was significantly (p<0.05) higher in TI sample but significantly (p<0.05) lower in T2 sample than those in comparison to the other treatments. Crude protein and fat content were significantly (p<0.05) higher in T2 sample compared to the other treatments. CIE $L^*$value was significantly (p<0.05) lower in T1 sample than those of other treatments until 5 weeks of cold storage. CIE $a^*$value was significantly (p<0.05) higher in T1 sample but significantly (p<0.05) lower in T2 sample than those in comparison to the other treatments until 5 weeks of cold storage. Hardness was significantly (p<0.05) higher in T4 sample compared to the other treatments during all cold storage. Cohesiveness was significantly (p<0.05) higher in T5 sample compared to the other treatments until 2 weeks of cold storage. The results of sensory evaluation showed that the meat flavor, taste and texture were significantly (p<0.05) lower in T5 sample compared to the other treatments whereas no difference among treatments except T5 sample. Overall acceptability was significantly (p<0.05) lower in T5 sample compared to the other treatments. Therefore, these results suggested that the ratio of 40% duck meat and 60% pork meat is appropriate levels for hardness and palatability when manufacturing emulsion type sausage with duck meat.

• KSBB Journal
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• v.14 no.3
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• pp.259-263
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• 1999

Fish oil was hydrolyzed with Aspergillus oryzae lipase, Lipolase-100T. The hydrolysis characteristics of Lipolsae-100T were investigated. Lipolase-100T showed 1,3-positional specificity which hydrolyzed acyl chains combined on the 1 or 3 position of triglyceride into free fatty acids. Lipolase-100T represented another property that the saturated fatty acids composing the triglyceride were hydrolyzed more easily that the polyunsaturated fatty acids(PUFAs). n-3 PUFAs, such as C16:4, C20:5 and C22:6, were hardly hydrolyzed, so that the concentrations of those in the mixture of glycerides were increased according to hydrolysis time. Especially docosahexaenoic acid(DHA), C22:6 showed the highest increase in the concentration. This result explained that n-3 PUFAs were combined on 2-position of triglyceride. When the hydrolysis of fish oil with Lipolase-100T 0.4 wt% was performed for 120 hr, n-3 PUFAs wt% was increased to 50 wt% in the mixture of glycerides. This result was obtained due to the 1,3-positional specificity of Lipolase-100T and positional specificity of n-3 PUFAs.

• Mineral and Industry
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• v.25
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• pp.1-10
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• 2012

In this present work, the froth flotation of lithium ore from Boam mine located in Wooljin, Kyungbuk has been carried out to produce high-grade lithium concentrate. The sample ore-Lepidolite mainly contained silicate mineral (quartz, muscovite) and calcite. In consequences of the experiment, it has been possible to obtain relatively high-grade lithium while using anionic acid (oleic acid) to remove calcite before the froth flotation for lithium concentrate. Among the amines collectors (Armac-T, Armac-C, Armafloat-18, Armafloat-1597), Armac-T has been relatively effective than another ones. Under the optimum condition (collector : Armac-T 100g/t, frother : AF65 50g/t, depressants : $Na_2SiO_3$ 600g/t and Lactic acid 100g/t, pulp density : 20%, pH 5.5, number of cleaning : 2), it has been obtained relatively high-grade lithium concentrate ($Li_2O$) with recovery of 80.3% and with grade of 4.33%.

• Progress in Medical Physics
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• v.13 no.4
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• pp.195-201
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• 2002

Several investigators have presented the effects of external magnetic fields on the dose distributions for clinical electron and photon beams. We focus the low energy electron beam with more lateral scatter In this study we calculated the beam profiles for an clinical electron beam of 6 MeV with longitudinal magnetic fields of 0.5 T-3.0 T using a Monte Carlo code. The principle of dose enhancements in the penumbra region is to deflect the laterally scattered electrons from its initial direction by the skewness of the laterally scattered electrons along the direction of magnetic field lines due to Lorentz force under longitudinal magnetic field. To discuss the dose enhancement effect on the penumbra area from the calculated results, we introduced the simple term of penumbra reduction ratio (PRR), which is defined as the percentage difference between the penumbra with and without magnetic field at the same depth. We found that the average PRR are 33%, and 49% over the depths of 1.5 cm, 2.0 cm, and 2.4 cm for the magnetic fields of 2.0 T and 3.0 T respectively. For the case of 0.5 T and 1.0 T the effects of magnetic filed were not observed significantly. In order to obtain the dose enhancement effects by the external magnetic field, we think that its strength should be more than 2 T approximately. We expect that the PRR would be saturated to 50-60% with magnetic fields of 3 T-5 T As a result of these calculations we found that the penumbra widths can be reduced with increased magnetic fields. This Penumbra reduction is explained as a result of electron lateral spread outside the geometrical edges of the beam in a longitudinal magnetic field. This means that the electron therapy benefits from the external magnetic fields.

• The Journal of Fisheries Business Administration
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• v.9 no.2
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• pp.45-58
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• 1978

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.403-404
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• 2007

• Bulletin of the Korean Mathematical Society
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• v.50 no.2
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• pp.687-696
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• 2013

In this note, we completely characterize the reducing subspaces of $T_{{z^N_1}{z^M_2}}$ on $A^2_{\alpha}(D^2)$ where ${\alpha}$ > -1 and N, M are positive integers with $N{\neq}M$, and show that the minimal reducing subspaces of $T_{{z^N_1}{z^M_2}}$ on the unweighted Bergman space and on the weighted Bergman space are different.

• Bulletin of the Korean Mathematical Society
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• v.50 no.2
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• pp.399-405
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• 2013

We explicitly construct a thin basis for the set $\mathbf{M}$ of monic polynomials in one variable $t$ over a finite field ${\mathbb{F}}_q$.