• Journal of the Korean Magnetics Society
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• v.20 no.6
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• pp.207-211
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• 2010

We have investigated the magnetoresistance effect in $Cr_5S_6$ single crystals prepared by vapor transport method. Room temperature X-ray diffraction (XRD) study reveals the phase formation of the single crystals with trigonal crystal structure. The magnetization was measured as a function of temperature (5 K~400 K) and applied magnetic field (0.1 T and 5 T). The magnetization curve as a function of temperature reveals the two transition states of $Cr_5S_6$: one from antiferromagnetic to ferrimagnetic state at ~150 K and the other from ferrimagnetic to paramagnetic state at ~300 K. Temperature dependent resistivity at 0 T and 5 T magnetic field shows the metallic behavior, showing the transition from antiferromagnetic to ferrimagnetic state at ~150 K. Magnetic field dependence of magnetization was measured at four fixed temperatures viz. 100 K, 150 K, 200 K, and 300 K. It is observed that at 200 K and 300 K it shows well M-H hysteresis behavior, whereas at 100 K and 150 K it shows non-hysteretic nature. A negative magnetoresistance (MR) of -2% is observed at 5 T for $Cr_5S_6$ single crystal at 150 K, near the antiferromagnetic transition temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.65-72
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• 1990

The mitotic cycle duration and component plase periods of rice (Oryza sativa L. 'Sumjinbyeo and Seokwangbyeo') root merisem cells at 15, 20, and 30$^{\circ}C$ were determined the use of tritiated thymidine, In this work, the time interval between the maxima of sequential mitotic appearances of marked cells was used to estimate the mitotic cycle duration (MCD) of rice, The MCD of rice of the cultivar 'Sumjinbyeo' and 'Seokwangbyeo' at 20. and 30$^{\circ}C$ was 12. and 20hr, respectively. But the MCD of 'Sumjinbyeo' and 'Seokwangbyeo' was 18 and 20hr, at 15$^{\circ}C$. respectively. The MCD decreased with increasing temperature, The duration of component phase of rice cultivar 'Seokwangbyeo' were essentially the same ratio at 20$^{\circ}C$ and 30$^{\circ}C$. but in 'Sumjinbyeo' cultivar the ratio of $G_1$ period was almost doubled while those of $G_2$ and M were decreased by almost two times at 20$^{\circ}C$ and 30$^{\circ}C$. Deoxyribonucleic acid (DNA). Ribonucleic acid (RNA), and protein synthesis were reduced with increasing temperature from 15$^{\circ}C$ to 30$^{\circ}C$ while the MCD was decreased, This result suggest that DNA, RNA and protein synthesis may not affect the MCD from 15$^{\circ}C$ to 30$^{\circ}C$ in rice.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.59-64
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• 2010

The effects of vinegar, alcohol and ascorbic acid on the color, microorganism, sensory properties and flavor pattern of minced ginger (MG) were investigated during storage for 28 days at $30^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) of the control (T-0) and all the treatments changed slightly at the initial stage of storage, however the elapse of time accelerated the changes. The total bacterial counts of T-0 showed $5.37{\times}10^7\;CFU/g$ at the initial stage, but the MG-treatments decreased the bacteria above 4 log compared to T-0. It was showed that the additives were effective for inhibition of the growth of microorganism. Sensory properties of flavor intensity test showed no significant difference between T-0 and MG-treatments (p < 0.05). The result of volatile flavor contents of electronic nose analyzer (ENZ) showed that MG-treatments (T-I, T-II, T-III) was recognized stronger than non-treatment at the initial stage, but the change of flavor compound were stabilized soon regardless of type or quantity of additives during total storage period at $30^{\circ}C$.

• Bulletin of the Korean Mathematical Society
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• v.26 no.2
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• pp.169-173
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• 1989

Let V={(x,y,z):f=z$^{n}$ -npz+(n-1)q=0 for n .geq. 3} be a compled analytic subvariety of a polydisc in $C^{3}$ where p=p(x,y) and q=q(x,y) are holomorphic near (x,y)=(0,0) and f is an irreducible Weierstrass polynomial in z of multiplicity n. Suppose that V has an isolated singular point at the origin. Recall that the z-discriminant of f is D(f)=c(p$^{n}$ -q$^{n-1}$) for some number c. Suppose that D(f) is square-free. then we prove that by Theorem 2.1 .mu.(p$^{n}$ -q$^{n-1}$)=.mu.(f)-(n-1)+n(n-2)I(p,q)+1 where .mu.(f), .mu. p$^{n}$ -q$^{n-1}$are the corresponding Milnor numbers of f, p$^{n}$ -q$^{n-1}$, respectively and I(p,q) is the intersection number of p and q at the origin. By one of applications suppose that W$_{t}$ ={(x,y,z):g$_{t}$ =z$^{n}$ -np$_{t}$ $^{n-1}$z+(n-1)q$_{t}$ $^{n-1}$=0} is a smooth family of complex analytic varieties near t=0 each of which has an isolated singularity at the origin, satisfying that the z-discriminant of g$_{t}$ , that is, D(g$_{t}$ ) is square-free. If .mu.(g$_{t}$ ) are constant near t=0, then we prove that the family of plane curves, D(g$_{t}$ ) are equisingular and also D(f$_{t}$ ) are equisingular near t=0 where f$_{t}$ =z$^{n}$ -np$_{t}$ z+(n-1)q$_{t}$ =0.}$ =0.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.19-25
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• 2006

The effect of vitamin E supplementation on plasma ${\alpha}$-tocopherol level, total antioxidant level and reproductive performance in Murrah buffaloes was studied during periparturient period. Twenty-four advance pregnant buffaloes were randomly divided into four equal groups as $T_1$, $T_2$, $T_3$ and $T_4$ and were supplemented with 0, 1,000, 1,500 and 2,000 IU of ${\alpha}$-tocopheryl acetate (Merck) from 60 days prepartum to 30 days postpartum and 0, 500, 750 and 1,000 IU from 30 to 60 days postpartum, respectively. Blood samples were collected at -60, -45, -30, -15, -7, 0, 7, 15, 30 and 60 days of parturition and were analyzed for plasma ${\alpha}$-tocopherol and total antioxidant activity (TAA). The intake of DM, CP and TDN did not vary among different groups. Plasma ${\alpha}$-tocopherol and TAA around parturition (-7 to 15 day) in $T_3$ and $T_4$ were significantly higher than the control group. There was 17% reduction in retention of fetal membranes (RFM) and metritis in $T_4$ than control. The post partum estrus interval averaged 58.00, 55.33, 51.83 and 43.00 days in $T_1$, $T_2$, $T_3$ and $T_4$ respectively. There was significant reduction in days open in both $T_3$ and $T_4$ in comparison to $T_1$ group (127,130 Vs.146). All the vitamin E supplemented groups showed reduction in days open than their previous lactation performance. Supplementation of vitamin E at $1,500IU\;d^{-1}$ from 60 day prepartum to 30 day post partum to buffaloes exhibited beneficial effect on plasma ${\alpha}$-tocopherol level and TAA around parturition and continuation of its supplementation at $1,000IU\;d^{-1}$ from 30 to 60 days of lactation improved post partum reproductive performance of buffaloes.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.65-71
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• 2009

Purpose: Transcranial direct current stimulation (tDCS) is a useful method for modulating the brain activity. This study compared the effect of continuous and interrupted tDCS using the change in the movement related cortical potential. Methods: Thirty healthy participants (male: 18 and female: 12) were assigned randomly to three groups; sham tDCS, continuous tDCS, which the current continuously flowed for 10 minutes, and interrupted tDCS, which the interrupted current flowed for 10 minutes (repetition: 4sec stimulation and 5sec rest) at an intensity of 1mA with anodal polarity. The effect of tDCS on the right primary motor area was measured from the movement related cortical potential (MRCP) before and after the experiment. MRCP consisted of the bereitshaftspotential (BP) and negative slope potential (NS) at Cz and C4. Results: Continuous and interrupted tDCS showed a significant difference in the changes in the BP, NS at Cz and C4 compared to the sham tDCS. However, there was no significant difference between the continuous tDCS and interrupted tDCS. Conclusion: The change in cortical activity by continuous and interrupted tDCS results from an improvement in the MRCP. An interrupted tDCS may be a safe and useful modality for stimulating the cortical region.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.74-81
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• 1985

Dimension analysis was used to estimate biomass and net primary production(NPP) in a 36-year-old Japanese red pine (Pines densiflora S. et Z.) natural forest in Kangwondo. Best estimation was made by the equation model of $Wt=aD^bH^c$ where Wt is weight in kg, D is DBH in cm, and H is total tree height in m. Total aboveground biomass was estimated at 198.82 t/ha. Organic matter was distributed in the Japanese red pine stand as follows ; bolewood 68.8%, live branches 16.5%, bolebark 5.4%, foliage 4.6%, dead branches 3.7%, and cones 0.6%. Net primary production was estimated at 15.87 t/㏊/yr and was distributed: bolewood 44.5%, live branches 30.9%, foliage 14.1%, current twig 7.1%, and bolebark 3.3%. Leaf efficiency was estimated at 1.876. The power equation for biomass and IVPP yielded similar results as the results for Pines densiflora in Japan.

• Journal of the Korean Applied Science and Technology
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• v.17 no.2
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• pp.113-119
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• 2000

Alkylation of phenol with tert-butanol in the liquid phase on mordenite was studied. The influence of many reaction parameters such as calcination temperature, reaction temperature, t-butanol/phenol molar ratio on catalytic properties was discussed. The main products were 2,4-di-t-butylphenol, o-t-butylphenol, p-t-butylphenol, the last of these was wanted product. In order to enhance the selectivity of p-t-butylphenol, optimum conditions were recommended at $500^{\circ}C$ calcination temperature, $140^{\circ}C$ reaction temperature, 1.0 molar ratio of reactants over mordenite. P-t-butylphenol was formed with 90% isomer selectivity at optimum conditions after 4hr reaction. On the basis of the behavior obtained in the cases mentioned, optimum conditions and catalytic properties for t-butylation of phenol were provided.

• Proceedings of the KSPS conference
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• 2007.05a
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• pp.187-192
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• 2007

The purpose of this paper is to show that the current notation of Japanese proper names in Korean has some problems. It cannot represent the different sounds between the voiced and voiceless. The purpose of this paper is also to give a more correct notation which is coherent and efficient. After introducing some general knowledge about the phonemes of Japanese language, I measured the Voice Onset Time of the stops[k, t] at the beginning, in the middle and at the end of a word, and compared the spectrogram of affricates with that of fricatives. In conclusion, Japanese voiceless [k, t ,$t{\int}$] should be written as [ㅋ,ㅌ,ㅊ] and voiced [g, d $d_3$] as [ㄱ,ㄷ,ㅈ] and the affricate[ts] as[ㅊ] in Korean.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2001.11a
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• pp.97-98
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• 2001

In Experiment 1, two hundred ten hatched broiler chickens(Ross) were assigned to seven dietary treatments for 5weeks. Each treatment was consisted of 3 replications with 10 birds per replication. Control diet was formulated 22%CP and 3,150kcaIME/kg for starter diet, 19%CP, 3,200kca1ME/kg for finisher diet. Euglena gracilis was added to control diet at the level of 0.25, 0.5, 1.0% and Euglena bleached(DHA enriched) at the level of 0.5, 1.0, 2.0% in the diet. 0 Experiment 2, two hundred fifty hatched broiler chickens(Ross) were assigned to five dietary treatments: T1; control, T2: T1 + Euglena gracilis(DHA enriched)0.5%, T3; T1 + Euglena gracilis(DHA enriched)1.0%, T4: T1 + Euglena bleached(DHA enriched)0.5%,T5: T1 $.$Euglena bleached(DHA enriched)1.0%. In Experiment 1, 2.0% Euglena bleached treatment showed highest DHA level in breast muscle(P<0.05), In Experiment 2, 1.0% Euglena bleached treatment showed highest EPA, Lignoceric acid and DHA level in breast muscle(P<0.05).