• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.338-341
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• 2011

Thin silicon ribbon was used for fabricating flexible silicon p-i-n junction devices, consisting of 100${\times}$100 arrays of pixels in 1 inch on the diagonal. Those passive matrix devices exhibited the rectification ratio $>10^{4}$ owing to smaller cross-talking current than that of p-n junction devices. P-i-n devices fabricated on silica/silicon substrates are easily detached by treatment with hydrofluoric acid and are subsequently transferred onto both PDMS and flexible PET film.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.385-385
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• 2012

A two terminal N+/P/N+ junction device to replace the conventional selective transistor was studied as a bilateral switching device for spin transfer torque (STT) MRAM based on 3D device simulation. An N+/P/N+ junction structure with $30{\times}30nm$ area requires bi-directional current flow enough to write a data by a drain induced barrier lowering (DIBL) under a reverse bias at N+/P (or P/N+ junction), and high current on/off ratio of 106. The SiGe materials are widely used in hetero-junction bipolar transistors, bipolar compensation metal-oxide semiconductors (BiCMOS) since the band gap of SiGe materials can be controlled by changing the fraction and the strain epilayers, and the drift mobility is increased with the increasing Ge content. In this work, N+/P/N+ SiGe material based junction provides that drive current is increased from 40 to $130{\mu}A$ by increased Ge content from 10~80%. When Ge content is about 20%, the drive current density of SiGe device substantially increased to 2~3 times better than Si-based junction device in case of 28 nm P length, which is sufficient current to operation of STT-MRAM.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.291-297
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• 2012

This study was carried out to investigate the effect of dietary phytase on nitrogen and phosphorus excretion of gestating and lactating sows (Yorkshire ${\times}$ Landrace ${\times}$ Duroc). Twelve gestating sows and twelve lactating sows were used in this study and were divided into 2 groups (1 control group and 1 treatment group, 6 replications/group) the control group was without phytase and the treatment group was fed with phytase (750 FTU/kg) in the diet, respectively. Body weights of gestating and lactating sows were $208.9{\pm}13.8$ kg and $190.5{\pm}22.9$ kg, respectively. In gestating sows, feed intake was greater in phytase fed group than the control (P<0.05), but water intake and total excretion were not different between the groups. In lactating sows, feed and water intakes and total excretion were not different between the groups. The N intake of lactating sows was higher in phytase fed group than control (P<0.05) but N excretion ratio was not different. In lactating sows, N intake and excretion and N excretion ratio were not significantly different between the groups. P excretion and excretion ratio in gestating sows decreased by phytase treatment (P<0.05) as compared to control. In lactating sows, N intake and excretion was not significantly different by added phytase (P>0.05). Finally, dietary addition of phytase decreased P excretion in feces of gestating and lactating sows.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.543-551
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• 1993

This study was designed to observe the effects of the feeding mixed with the sardine oil containing n-3 EPA, DHA and the safflower oil in which rich n-6 linoleic acid on the improvement of the lipids and on the fatty acid matabolism of serum lipoprotein in the dietary hyperlipidemic rats. Experimental oils mixed with 16% butter(control group) and 8% butter+8% olive oil, 8% butter and various level of sardine and safflower oils were administered to the male rats of the Sprague Dawley for 4 weeks. Concentrations of total cholesterol in serum lipoproteins were highest in the LDL, followed by VLDL, HDL and chylomicron components. in the triglyceride concentrations, chylomicron were highest, and much VLDL, LDL, HDL components. There were highest in the HDL, followed by LDL, VLDL and chylomicron in phospholipid concentrations of serum lipoproteins. Concentrations of total cholesterol, triglyceride and phospholipid in serum lipoprotein were lower in the other groups than in the control groups, and particularly, lowest in the group 5(4% sardine oil+4% safflower oil). From this results, the feeding equal quantity mixed oil with n-3 PUFA rich sardine oil and n-6 PUFA rich safflower oil were effective on the improvement of the lipid composition in the serum lipoprotein. It might be due to the effects of appropriate rations of P/S, 0.85 and n-6/n-3P, 2.85 in the test lipids. In the fatty acid composition of serum lipoprotein, ratio of P/S and n-3/n-6P were influenced from the fatty acid compositions of the mixed test lipids. And EPA contents were higher in the chylomicron components.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.311-318
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• 1997

Chemical properties of soil(N, P, K, Ca, Na, Mg, CEC, and pH) were studied after annual additions of $NH_4NO_3$(336kg/ha N), treble superphosphate(112kg/ha P), and KCl(224kg/ha K) fertilizers in a willow(Salix spp.) bioenergy plantation. Soil samples were collected from November through December 1992 from previously established the fertilized and non-fertilized willow plantation at Tully, New York, U.S.A. in 1987. Total fertilizer additions from 1987 through 1991 were 1,680kg/ha N and 560kg/ha P and 1.120kg/ha K. Fertilization with N, P, and K resulted in no difference in total soil N content between the fertilized and non-fertilized plots, increased soil P and K, decreased base cations ($Ca^{2+}$ and $Mg^{2+}$) and soil pH, and increased soil pH with soil depth. Strong positive correlations of soil carbon to soil N, Ca, Mg, and CEC were noted. Soil C/N ratio in the study plots ranged from 9.6 to 11.2 for all treatment combinations. Significant differences in soil P, K, Ca, and pH between the fertilized and non-fertilized plots indicate that fertilization had changed chemical properties of soil in this fertilizer trial.

• Nutritional Sciences
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• v.5 no.4
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• pp.184-189
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• 2002

The effects of dietary Int levels on lipid metabolism under fixed P/S (1.3) and n-6/n-3 (5.1) fatty acid ratios were examined in rats using palm oil, soybean oil and perilla oil. These ratios correspond to the recommended composition of dietary fat for humans. The range of dietary fat levels was 5-20% by weight (11.8-39.3% of total energy). The levels of dietary fat did not influence the concentrations of serum and liver cholesterol, whereas the level of triglycerides was gradually elevated with increasing levels of dietary fat, especially in the liver. The fatty acid composition of tissue phosphatidylcholine seemed to vary with the different levels of fat. The ratio of linoleic acid to arachidonic acid was increased more significantly in the heart than in the liver. In adipose tissue total lipids, the percentages of saturated and monounsaturated fatty acids decreased, whereas the percentage of polyunsaturated fatty acid increased, with increasing dietary Int levels. In addition, though the level of aortic prostacyclin was not uniformly affected by increasing dietary fat levels, thromboxane A2 production by platelets tended to increase with higher levels of dietary fat, suggesting an increased risk of thrombosis in this situation. Thus, even though dietary fat may have desirable compositions of fatty acids, these excessive consumption can produce unfavorable metabolic responses.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.4
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• pp.21-27
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• 2009

In this work, Er-silicided SB-SOI nMOSFET and Pt-silicided SB-SOI pMOSFET have been fabricated to investigate the current-voltage characteristics of Schottky barrier SOI nMOS and pMOS at elevated temperature. The dominant current transport mechanism of SB nMOS and pMOS is discussed using the measurement results of the temperature dependence of drain current with gate voltages. It is observed that the drain current increases with the increase of operating temperature at low gate voltage due to the increase of thermal emission and tunneling current. But the drain current is decreased at high gate voltage due to the decrease of the drift current. It is observed that the ON/Off current ratio is decreased due to the increased tunneling current from the drain to channel region although the ON current is increased at elevated temperature. The threshold voltage variation with temperature is smaller and the subthreshold swing is larger in SB-SOI nMOS and pMOS than in SOI devices or in bulk MOSFETs.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.291-295
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• 2008

Weight loss and nutrient dynamics of oak and pine leaf litter during decomposition were investigated from December 2005 through June 2008 at Mt. Worak National Park as a part of National Long-Term Ecological Research Program in Korea. The decay constant (k) of oak and pine leaf litter were 0.314 and 0.217, respectively. After 30 months decomposition, remaining weight of oak and pine leaf litter was 45.5% and 58.1%, respectively. Initial C/N ratio of oak and pine leaf litter was 53.4 and 153.0, respectively. Carbon % of initial oak and pine leaf litter was similar with each other; however, nitrogen content of initial oak leaf litter (0.85%) was greater than that of initial pine leaf litter (0.33%). N and P concentration in both decomposing leaf litter increased significantly during decomposition. There was no net N and P mineralization period in decomposing pine leaf litter. K, Ca and Mg concentration in both decomposing leaf litter showed different pattern with those of N and P. After 30 months decomposition, remaining nutrients in oak and pine leaf litter were 97.7 and 216.2% for N, 123.2 and 216.5% for P, 39.3 and 44.8% for K, 47.9 and 40.6% for Ca, 30.7 and 51.2% for Mg, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.65.2-66
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• 2021

Observational studies of supernova (SN) feedback are limited. In our galaxy, most supernova remnants (SNRs) are located in the Galactic plane, so there is contamination from foreground/background sources. SNRs located in other galaxies are too far, so we cannot study them in detail. The Large Magellanic Cloud (LMC) is a unique place to study the SN feedback due to their proximity, which makes possible to study the structure of individual SNRs in some detail together with their environment. Recently, we carried out a systematic study of 13 LMC SNRs using [P II] (1.189 ㎛) and [Fe II] (1.257 ㎛) narrowband imaging with SIRIUS/IRSF, four SNRs (SN 1987A, N158A, N157B and N206), show [P II]/[Fe II] ratio much higher than the cosmic abundance. While the high ratio of SN 1987A could be due to enhanced abundance in SN ejecta, we do not have a clear explanation for the other cases. We investigate the [P II] knots found in SNRs N206, N157B and N158A, using optical spectra obtained last November with GMOS-S mounted on Gemini-South telescope. We detected several emission lines (e.g., H I, [O I], He I, [O III], [N II] and [S II]) that are present in all three SNRs, among other lines that are only found in some of them (e.g., [Ne III], [Fe III] and [Fe II]). Various line ratios are measured from the three SNRs, which indicate that the ratios of N157B tend to differ from those of other two SNRs. We will use the abundances of He and N (from the detection of [N II] and He I emission lines), together with velocity measurements to tell whether the origin of the [P II] knots are SN ejecta or CSM/ISM. For this purpose we have built a family of radiative shock with self-consistent pre-ionization using MAPPINGS 5.1.18, with shock velocities in the range of 100 to 475 km/s. We will compare the observed and modeled line fluxes for different depletion factors.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1010-1015
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• 2011

The objectives of this study were to investigate soil chemical characteristics for forest rehabilitation and suggest management in abandoned coal mine areas in Hwasun-gun, South Jeolla Province. Total study sites were 8 sites, and soil analysis particular were soil pH, TOC, total-N, C/N ratio, Avail. $P_2O_5$, and CEC. Average soil pH was 5.8 (4.7~6.4). Average contents of TOC, total-N and C/N ratio were 1.1% (0.2~2.0%), 0.08% (0.02~0.13%) and 15.0 (7.9~31.4), respectively. Average Avail. $P_2O_5$ was $8.3mg\;kg^{-1}$ (2.7~15.0) and Average CEC was $13.7cmol_c\;kg^{-1}$ ($9.9{\sim}18.5cmol_c\;kg^{-1}$). Soil pH was decreased according to elapsed time from forest rehabilitation, while TOC, total N and CEC were increased. Av. $P_2O_5$ did not show any relationship with elapsed time. Soil pH was stable comparing with general forest soil in South Jeolla Province (5.1), while contents of TOC and total N were lower than general forest soil in South Jeolla Province (4.9% and 0.18%, respectively). Therefore, sustainable managements such as fertilization for TOC and total N are necessary for good rooting and growth of vegetation.