• Journal of Environmental Health Sciences
• /
• v.27 no.1
• /
• pp.56-62
• /
• 2001

The investigation was carried out to analyze the generation and the composition of landfill gas generated from inserted pipe wells into the underground by boring operation and also study the undecomposed waste characteristics by open-cut test at S. waste landfill site in Pusan city. Pilot test was conducted for stabilization. The experimental results from this study were summerized as follows. ; Since COD matter was easuer decomposed than COD matter for continuously biological stabilization in underground, it seemed that BOD and CO $D_{Mn}$ were in the range of 854~4,813mg/$\ell$ and 1,156~6,977mg/$\ell$ and their ratio were generally as high as 0.55~0.74. As C $H_4$ compositions of generated gas were measured in the range of 37.36~60.1%, we could know that C $H_4$ gas was actively generated. Organic matters by open-cut test averaged 13.4~16.6% at each landfill layer, and considering rate of combustible compositions(36.2~66.5%) for landfilling wastes, they have been actively decomposed. The measured and theoretical values of generated gas in waste landfill site were almost similar to C $H_4$ 50.0% and 53.4%, $CO_2$ 39.63% and 45.24%, and after 0.5$^{\circ}C$ with heavy depth and long landfill period. From the results of pilot test for stabilization, after 180 days organic matters were actively decomposed beyond 2.2 times in facultative aerobic lystimeter(B) to exsiting anaerobic lysimeter(A). Therefore, it seemed that landfill site was of benefical to the conversion of facultative aerobic for stabilization.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.10
• /
• pp.1485-1489
• /
• 2007

Achaete-scute like 2 (ASCL2) gene encodes a member of the basic helix-loop-helix transcription factor which is essential for the maintenance of proliferating trophoblasts during placental development. ASCL2 gene preferentially expresses the maternal allele in the mouse. However, it escapes genomic imprinting in the human. In this study, the complete open reading frame consisting of 193 amino acids of ASCL2 gene was obtained. Sequence analysis indicated that a C-G mutation existed in the 3' region between Meishan and Large White pigs. The polymorphism was used to determine the monoallelic or biallelic expression with RT-PCR-RFLP in pigs of Large $White{\times}Meishan$ $F_1$ hybrids. Imprinting analysis indicated that the ASCL2 gene expression was biallelic in all the tested tissues (heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus, ovary and pituitary). PCR-RFLP was used to detect the polymorphism in 270 pigs of the "$Large\;White{\times}Meishan$" $F_2$ resource population. The statistical results showed highly significant associations of the genotypes and fat meat percentage (FMP), lean meat percentage (LMP) and ratio of lean to fat (RLF) (p<0.01), and significant associations of the genotypes and loin eye area (LEA) and internal fat rate (IFR) (p<0.05).

• Journal of Advanced Navigation Technology
• /
• v.12 no.2
• /
• pp.139-145
• /
• 2008

There has been lots of studies on communication systems using millimeter wave recently in many countries, specially in newly assigned 57GHz ~ 64GHz ISM band. Among those studies, IEEE 802.15.3c standard proposes OFDM (Orthogonal Frequency Division Multiplexing) systems for high data rate transmission support. But OFDM method has the PAPR (peak-to-Average Power Radio) problem The PAPR problem is to decline the performance of the transmission system due to signals distorted severely when passing through nonlinear components such as ADC/DAC and power amplifiers. In order to solve the problem of P APR, this paper suggests SSC (Sine Soft Clipping) and analyzes the PAPR, CCDF, PSD, BER by applying SAW(Surface Acoustic Wave) filter and power amplifiers to IEEE 802.15.3.c OFDM WPAN systems.

• Progress in Superconductivity
• /
• v.6 no.2
• /
• pp.118-123
• /
• 2005

A low cost YBCO oxide powder was employed as a starting precursor for MOD process. YBCO oxide is advantageous over metal acetates or TFA salts which are popular starting precursors for conventional MOD-TFA process because that YBCO oxide precursor is cheap and easy to control molar ratio. YBCO thin films were prepared by this oxide-precursor-based MOD process and annealing condition was optimized. The YBCO thin film annealed at below $780^{\circ}C$ shows no transport $I_c$ and poor microstructure. Raman spectroscopic study of YBCO thin film indicates that YBCO thin film prepared at below $780^{\circ}C$ contains a number of imperfections such as non-superconducting $BaCuO_2$ phase, cation disorder, etc. However, the YBCO thin film treated at above $800^{\circ}C$ shows improvement in microstructure and current transport properties. This research was supported by a grant from Center for Applied Superconductivity Technology of the 21st Century Frontier R&D Program funded by the Ministry of Science and Technology, Republic of Korea.

• Korean Journal of Food Science and Technology
• /
• v.43 no.3
• /
• pp.369-374
• /
• 2011

A putative maltogenic amylase gene (DGMA) was cloned from the Deinococcus geothermalis DSM 11300 genome using the polymerase chain reaction. The gene encoded 608 amino acids with a predicted molecular mass of 68,704 Da. The recombinant DGMA was constitutively expressed using the pHCXHD plasmid. As expected, the recombinant DGMA hydrolyzed cyclodextrins and starch to maltose and pullulan to panose by cleaving the ${\alpha}$-(1,4)-glycosidic linkages, as observed for typical maltogenic amylases. Characterization of the recombinant DGMA revealed that the highest maltogenic amylase activity occurred at $40^{\circ}C$ and pH 6.0. The half-life of catalytic activity at $65^{\circ}C$ and $55^{\circ}C$ were 8.2 min and 187.4 min, respectively. DGMA mainly hydrolyzed ${\beta}$-cyclodextrin, soluble starch, and pullulan and its efficient ratio of those substrates was 9:4.5:1.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.11a
• /
• pp.317-321
• /
• 2002

Piezoelectric properties of $(Pb_{1-x}Y_x)[(Ni_{1/3}Nb_{2/3})_{0.15}(Zr_{1/2}Ti_{1/2)})_{0.85}]O_{3}$ (x=0~0.05) ceramics were investigated, The stoichiometric PNN-PZT ceramics required the sintering temperature above $1100^{\circ}C$, but the addition of $Y_{2}O_{3}$ in the PNN-PZT ceramic lowered the sintering temperature down to $1000^{\circ}C$. In case of x=0.005, the electro-mechanical coupling $factor(K_p)$, the piezoelectric $constant(d_{33})$, and the maximum strain ratio of PNN-PZT ceramics sintered at $1000^{\circ}C$ were 53.1%, 395pC/N, and $2200{\times}10^{-6}$ respectively, A 30-layer piezoelectric actuator$(10{\times}10{\times}1.7mm)$ fabricated with the above material showed the maximum strain of $2.09{\mu}m$ under 100V DC bias.

• Journal of Drive and Control
• /
• v.9 no.4
• /
• pp.52-57
• /
• 2012

In this study, in order to understand contents and ranges of design for the EGR Valve test system for improving quality and performance of EGR Valve, engine performance and exhaust gas characteristic of 3L-class diesel engine was analyzed. Experimental operation of engine performance test was performed with 50% engine load and 20% and 100% opening ratio of EGR Valve. From test of performance and exhaust gas characteristic of engine, torque output of engine and temperature and pressure of inlet and outlet of EGR Valve were measured. As a result, for design of EGR Valve test system, input fluid flow of EGR Valve must be set the same amount with exhaust gas flow that was below of engine speed of 2,500 rpm, and temperature of inlet of EGR Valve must be set under about $510^{\circ}C$. And the difference of temperature between inlet and outlet of EGR Valve must be over than about $200^{\circ}C$. Exhaust gas of inlet and outlet of EGR Valve were under 1 bar that was not considerable, and the difference of pressure between inlet and outlet of EGR Valve were under 1 bar that could not effect on mechanical operation of EGR Valve.

• Journal of Ginseng Research
• /
• v.36 no.2
• /
• pp.198-204
• /
• 2012

An light-emitting diode (LED)-based light source was used as a monochromatic light source to determine the responses of raw ginseng roots (Panax ginseng Meyer) to specific emission spectra with respect to the production of ginsenosides. The ginsenoside content in the ginseng roots changed in response to the LED light treatments at $25^{\circ}C$ relative to the levels in the control roots that were treated in the dark or at $4^{\circ}C$ for 7 d. Ginseng roots were exposed to LEDs with four different peak emission wavelengths, 380, 450, 470, and 660 nm, in closed compartments. Compared with the control $4^{\circ}C$-treated roots, roots that were treated with 450 and 470 nm light showed a significantly increased production of ginsenosides (p<0.05), with increases of 64.9% and 74.1%, respectively. The contents of the ginsenosides $Rb_2$, Rc, and $Rg_1$ were significantly higher (p<0.05) in the 450 and 470 nm-treated root samples. The ratio of protopanaxadiol ginsenosides ($Rb_1$, $Rb_2$, Rc, and Rd) to protopanaxatriol ginsenosides ($Rb_1$, $Rb_2$, Re, and Rf) was significantly higher (p<0.05) in the 450 and 470 nm-treated root samples than in the control $4^{\circ}C$-treated roots. This is the first report that demonstrates the increase and conversion of ginsenosides in raw ginseng roots in response to exposure to LED light.

• Resources Recycling
• /
• v.3 no.1
• /
• pp.9-16
• /
• 1994

Fine cobalt metal powders was produced from domestic Stellite scrap by decomposing it with molten sodium hydroxide. Complete decomposition of the scrap could be obtained with the weigth ratio of sodium hydroxide to Stellite being about 2 at the temperature ranges of $750~800^{\circ}C$ for an hour. The cobalt-bearing compound was identified as $Co_2O_3{\dot}H_2O$ by X-ray analysis and D.T.-T.G.a.. The compound was then digested in HCI to form cobalt chloride, and after iron removal by adjusting the pH of the solution, cobaltous or cobaltic hydroxide was precipitated at the pH of about 13 or 4, respectively. The precipitates were reduced by hydrogen in the temperatures of $400~500^{\circ}C$ to fine cobalt powders of high purity with the size of 1.0 to $1.5\mu\textrm{m}$. The recovery of cobalt from Stellite scrap was about 75~86% by weight.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2005.09a
• /
• pp.193-196
• /
• 2005

Low resistance Ni thin films for using NiSi formation and metallization by atomic layer deposition (ALD) method have been studied. ALD temperature window is formed between $200^{\circ}C\;and\;250^{\circ}C$ with deposition rate of $1.25{\AA}$/cycle. The minimum resistance of deposited Ni films shows $4.333\;{\Omega}/\square$ on the $SiO_2/Si$ substrate by $H_2$ direct purging process. The reason of showing the low resistance is believed to be due to format ion of the $Ni_3C$ phase by residual carbon in Bis-Ni The deposited film exhibits excellent step coverage in the trench having 1(100 nm) : 16 (1.6 um) aspect ratio.