• Korean Journal of Materials Research
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• v.5 no.8
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• pp.1040-1044
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• 1995

Magnetic garnet films of (YSmLuCa)$_3$(FeGe)$\_$5/O$\_$12/ have been grown by the liquid phase eqitaxy method on the substrate of non-magnetic garnet Gd$_3$Ga$\_$5/O$\_$12/. The variation of Sm ion concentration were varied 0.3, 0.4, 0.6, mole/formula unit respectively. The magnetic properties of the samples for the bubble magnetic materials, such as, line width ΔH of ferromagnetic resonance (FMR), magnetic saturation induction 4$\pi$Ms, wall mobility u$\_$w/ uniaxial magnetic anisotropy energy Ku, were measured and discussed the relations between these properties. The line width ΔH decreases with increasing 4$\pi$Ms, and with decreasing Sm concentration. The anisotropy energy Ku increases not only with increasing Sm ion concentration, but also increasing 4$\pi$Ms. The value of wall mobility u$\_$w/ increase with increasing 4$\pi$Ms and decreases with increasing Sm concentration. We define a physical constant Eι from the fact that the product of 4$\pi$Ms and ΔH is constant with dimension of energy density. The Eι is dependent only on Sm concentration.density. The Eι is dependent only on Sm concentration.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.218-224
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• 2001

To find out the optimum level of slow release N fertilizers (MS 10, MS S10, LCU 80, and LCU 100), total amount of nitrogen required throughout the growing season were applied in the seedling box or incorporated into paddy soil. Four levels of the slow release N fertilizers (0, 6, 9 and 12 kg N/10 a) were mixed with commercial rice nursery bed soil. N release rate and electrical conductivity(EC) of the slow release fertilizers were greater in the order of MS 10 > LCU 80 ${\fallingdotseq}$ LCU 100 > MS S10 and higher as temperature increased. No seedlings were emerged in all MS 10 plots. The seedling emergence rate of LCU 80 and LCU 100 decreased as the N level increased and seedlings were wilted severely on the 13th day after sowing at 9 and 12 kg N/10 a. In MS S10 plots the emergence rate was higher than 80% at all N levels and seedling growth was normal until 30 days after sowing. Yield of rice was similar between seedling box application and soil incorporation in paddy of MS S10. Yield of rice among the 6, 9, 12 kg N/10 a of MS S10 and conventional 12 kg N/10 a of urea split application was similar, but it was significantly higher compared with no N plot. Fertilizer N recovery of MS S10 decreased as fertilizer level increased and it was significantly higher compared with conventional urea split application.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.8
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• pp.56-63
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• 2010

This work proposes a 12b 100MS/s 0.13um CMOS pipeline ADC for battery-powered mobile video applications such as DVB-Handheld (DVB-H), DVB-Terrestrial (DVB-T), Satellite DMB (SDMB), and Terrestrial DMB (TDMB) requiring high resolution, low power, and small size at high speed. The proposed ADC employs a three-step pipeline architecture to optimize power consumption and chip area at the target resolution and sampling rate. A single shared and switched op-amp for two MDACs removes a memory effect and a switching time delay, resulting in a fast signal settling. A two-step reference selection scheme for the last-stage 6b FLASH ADC reduces power consumption and chip area by 50%. The prototype ADC in a 0.13um 1P7M CMOS technology demonstrates a measured DNL and INL within 0.40LSB and 1.79LSB, respectively. The ADC shows a maximum SNDR of 60.0dB and a maximum SFDR of 72.4dB at 100MS/s, respectively. The ADC with an active die area of 0.92 $mm^2$ consumes 24mW at 1.0V and 100MS/s. The FOM, power/($f_s{\times}2^{ENOB}$), of 0.29pJ/conv. is the lowest of ever reported 12b 100MS/s ADCs.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.9
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• pp.685-691
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• 2003

This work describes a 3 V 12b 100 MS/s CMOS digital-to-analog converter (DAC) for high-speed communication system applications. The proposed DAC is composed of a unit current-cell matrix for 8 MSBs and a binary-weighted array for 4 LSBs, considering linearity, power consumption, chip area, and glitch energy. The low-glitch switch driving circuit is employed to improve the linearity and the dynamic performance. Current sources of the DAC are laid out separately from the current-cell switch matrix core. The prototype DAC is implemented in a 0.35 urn n-well single-poly quad-metal CMOS technology. The measured DNL and INL of the prototype DAC are within $\pm$0.75 LSB and $\pm$1.73 LSB, respectively, and the spurious-free dynamic range (SFDR) is 64 dB at 100 MS/s with a 10 MHz input sinewave. The DAC dissipates 91 mW at 3 V and occupies the active die area of 2.2 mm ${\times}$ 2.0 mm.

• Journal of Genetic Medicine
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• v.5 no.1
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• pp.21-25
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• 2008

Purpose : In recent years, many countries have adopted newborn screening programs that use tandem mass spectrometry (MS/MS) to screen and the number of diseases screened has also increased. We began screening for inherited metabolic disorders using MS/MS in April, 2001. Our goal was to determine the overall prevalence of metabolic disorders and to assess the effectiveness of newborn screening by MS/MS in Korea. Methods : From April, 2001 to December, 2007, we screened newborns and high risk groups using MS/MS. Acylcarnitines and amino acids were extracted and butylated and were introduced into the inlet of MS/MS. Confirmatory testing including a repeat newborn screening, and urine organic acid and plasma amino acid analysis were performed on a case-by-case basis. Results : The total number of screened subjects 284,933 which comprised 251,799 neonates and 33,134 high risk subjects. The recall rate was 0.4% (1158 tests) and true positive cases were 117 (0.04%). Confirmed metabolic disorders (newborn/high risk group) were as follows; 78 (25/53) amino acid disorders, 27 (16/11) organic acid disorders, and 12 (5/7) fatty acid oxidation disorders. The estimated prevalence of inherited metabolic diseases in newborns was 1:5,000 and that in the total group was 1:2,000. Conclusion : Newborn screening by MS/MS improved the detection of many inherited metabolic disorders. We therefore propose that all newborns be screened by a MS/MS national program and followed-up using a systemic organization strategy.

• Journal of IKEEE
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• v.25 no.2
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• pp.302-308
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• 2021

A 12-bit 10-MS/s pipeline analog-to-digital converter (ADC) is proposed for image processing applications. The proposed pipeline ADC consists of a sample and hold amplifier, three stages, a 3-bit flash analog-to-digital converter, and a digital error corrector. Each stage is operated by using a 4-bit flash ADC (FADC) and a multiplying digital-to-analog converter (MDAC). The proposed sample and hold amplifier increases the voltage gain using gain boosting for the ADC with high resolution. The proposed pipelined ADC is designed using a 180-nm CMOS process with a supply voltage of 1.8 and it has an effective number of bit (ENOB) of 10.52 bits at sampling rate of 10MS/s for a 1-V_pp differential sinusoidal analog input with frequency of 1 MHz. The measured ENOB is 10.12 bits when the frequency of the sinusoidal analog input signal is a Nyquist frequency of approximately 5 MHz.

• Mass Spectrometry Letters
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• v.12 no.4
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• pp.126-130
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• 2021

The mass spectrometry (MS) provides the mass-to-charge ratios of atoms, molecules, stable/metastable complexes, and their fragments. I have taken a long journey with MS to address outstanding issues and problems by experiments and theory and gain insights into underlying principles in chemistry. By looking through the mass-to-charge ratio, I have studied thermochemical problems in silicon chemistry, the infrared multiphoton dissociation spectroscopy of organometallic intermediates, unimolecular dissociations of halotoluene radical cations, and the kinetics of association/dissociation of alkali halide triple ions with Lewis bases. Various MS platforms have been used to characterize non-covalent interactions between porphyrins and fullerenes and those between the group IIB ions and trioctylchalcogenides, and to examine the binding of the group IA, IIA and porphyrin ions to G-quadruplex DNA. Recently, I have focused on mass-balanced H/D isotope dipeptide tags for MS-based quantitative proteomics, a simple chemical modification method for MS-based lipase assay, and the kinetics and dynamics of energy-variable collision-induced dissociation of chemically modified peptides. Now, I see an important role of MS in global issues in the post-COVID era, as the society demands high standards for indoor air quality to contain the airborne-pathogen transmission as well as in-situ monitoring and tracking of carbon emissions to reduce global warming.

• Mass Spectrometry Letters
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• v.12 no.4
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• pp.163-171
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• 2021

Emiliania huxleyi is a marine phytoplankton that plays a critical role in global carbon and sulfur cycling. The genome of E. huxleyi has been sequenced, and an in-depth proteomic profile of this organism has been reported. This study analyzed the phosphoproteome of E. huxleyi and identified its changes under calcium-limited conditions. A TiO₂ microcolumn was used for phosphopeptide enrichment, followed by liquid chromatography-tandem mass spectrometry analysis. Overall, we identified 7,010 phosphorylated sites on 3,355 phosphopeptides associated with 2,929 phosphoproteins in E. huxleyi. Quantitative analysis revealed changes in the phosphoproteome in E. huxleyi when ambient conditions changed to calcium-limited conditions, notably the phosphorylation of some transporters was altered. This study provides an overview of protein phosphorylation in E. huxleyi and paves the way for further investigations of its biological functions.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.6
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• pp.118-125
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• 2018

This study aimed to obtain data for a comparative analysis of the properties of bio aviation fuel to be developed in the future by measuring and comparing the ignition delay times of various presently used aviation fuels. In the case of petroleum-based aviation fuel, the ignition delay time of exo-THDCP was 4.92 ms, which was 3.42 times longer than 1.44 ms of Jet A-1 at $590^{\circ}C$ / 55 bar. In the case of foreign bio aviation fuel, the ignition delay time of 11POSF7629 was the longest (1.16 ms), while the ignition delay time of 10POSF6308 (1.06 ms), 12POSF7720 (1.07 ms), and 07POSF5172 (1.05 ms) were similar.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.187-193
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• 2005

A protocol was developed for somatic embryogenesis with 100% induction rate from immature zygotic embryo axes of peanut (Arachis hypogaea L. cv. DRG-12) cultured on MS medium containing $18.09\;{\mu}M$ 2,4-D. The frequency of somatic embryogenesis (31.7%) as well as the number of somatic embryos induced per explant (6.6) decreased when the concentration of 2,4-D was increased to $72.4\;{\mu}M$. Morphologically abnormal somatic embryos were observed at a frequency of 43.3% on MS medium containing $72.4\;{\mu}M$ 2,4-D. Somatic embryos isolated from 30-day-old cultures of immature zygotic embryo axes exhibited precocious germination with varied responses when placed on MS basal medium with 3% sucrose. Maximum shoot induction (80.0%) was observed from somatic embryos isolated from 60-day-old cultures of immature zygotic embryo axes when placed as a clump rather than individually on MS medium supplemented with $26.63\;{\mu}M$ BA and $0.54\;{\mu}M$ NAA. Shoots developed from somatic embryos rooted with higher frequency (93.3%) on Blaydes' medium containing $5.4\;{\mu}M$ NAA.