• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.174-179
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• 2013

This paper presents a capacitor loaded tunable bandpass chip filter using multiple split ring resonators (MSRRs) with two transmission zeros. To obtain high selectivity and minimize the chip size, asymmetric feed lines are adopted to make a pair of transmission zeros located on each side of passband. Compared with conventional filters using cross-coupling or source-load coupling techniques, the proposed filter uses only two resonators to achieve high selectivity through a pair of transmission zeros. In order to optimize selectivity and sensitivity (insertion loss) of the filter, the effect of the position of asymmetric feed line on transmission zeros and insertion loss is analyzed. The SOI-CMOS switched capacitor composed of metal-insulator-metal (MIM) capacitor and stacked-FETs is loaded at outer rings of MSRRs to tune passband frequency and handle high power signal up to +30 dBm. By turning on or off the gate of the transistors, the passband frequency can be shifted from 4GH to 5GHz. The proposed on-chip filter is implemented in 0.18-${\mu}m$ SOI CMOS technology that makes it possible to integrate high-Q passive devices and stacked-FETs. The designed filter shows miniaturized size of only $4mm{\times}2mm$ (i.e., $0.177{\lambda}g{\times}0.088{\lambda}g$), where ${\lambda}g$ denotes the guided wave length of the $50{\Omega}$ microstrip line at center frequency. The measured insertion loss (S21)is about 5.1dB and 6.9dB at 5.4GHz and 4.5GHz, respectively. The designed filter shows out-of-band rejection greater than 20dB at 500MHz offset from center frequency.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.158-167
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• 2015

A lateral flow immunoassay kit based on antigen-antibody interactions was developed to detect residues of beta-lactams, quinolones, tetracyclines, and sulfonamides in farmed fish. Group-specific antibodies showing cross-reactivity with other antibiotics in the same group were produced in rabbits. The rabbits were immunized eight times to obtain the maximum titers. Antibodies were extracted from the antisera collected from the immunized rabbits and produced group-specific reactions with antibiotics from the four groups. A kit was prepared that optimize conditions for the antigen-antibody reaction, using colloidal gold conjugated antibodies, and was designed to detect the four groups of antibiotics simultaneously. The kit enabled the detection of antibiotics in the four groups at below maximum residue limits (MRLs), which were $200{\mu}g/kg$ for tetracyclines, $100{\mu}g/kg$ for sulfonamides, $50{\mu}g/kg$ for beta-lactams, and $100{\mu}g/kg$ for quinolones. The cross-reactivity of the antibodies ranged from 10-80% for the sulfonamides, 20-100% for tetracyclines, 38-100% for quinolones, and 20-100% for the beta-lactams, confirming that the antibodies were group specific. The test kit was used 30 times to examine spiked antibiotics at the limits of detection (LODs) and all produced positive results, indicating high sensitivity. The LODs for the assay ranged from 4-20 ng/mL for beta-lactams, 25-50 ng/mL for sulfonamides, 20-100 ng/mL for tetracyclines, and 30-80 ng/mL for quinolones, and there were no false negative reactions at above these LODs. In addition, all of the LODs of the developed kit were correlated with high-performance liquid chromatography (HPLC) data. Our lateral flow immunoassay kit can simultaneously detect antibiotic residues from a large number of fish samples rapidly, strengthening the safety of domestic farmed and imported fish.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.31-38
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• 1998

In Korea, all domestic made test systems for detecting antibodies in HIV-1 contain the antigens from human immunodeficiency type 1 (HIV-1) subtype B. However, because HIV-1 subtype O is significantly different in amino acid sequences from all other subtypes of HIV-1, there has been a need for developing a test for detecting antibodies in subtype O. For this purpose, the entire nucleotide sequence corresponding to the extracellular domain of the transmembrane glycoprotein of HIV-1 subtype O was synthesized with consideration of Escherichia coli condon usage. Various regions of the extracellular domain were cloned into E. coli expression vectors and tested for levels of protein production. The nucleotide sequence, named ECTM, that can encode a 129 amino acid-long peptide, was found to be expressed at a high level in E. coli. The protein of approximately 17 kDa specifically reacted with sera from individuals infected with HIV-1 subtype O. The ECTM protein was purified to near homogeneity by the CM-T gel chromatography, using concentrated, denatured inclusion bodies. In Western blot analysis, the purified viral antigen reacted with sera from individuals infected with subtype O more efficiently than subtype B. The enzyme linked immunoabsorbent assay (ELISA) system was developed using the subtype O viral protein and compared with the commercially available kit lacking the antigens from subtype O. The ELISA kit containing the subtype O antigen ECTM alone efficiently reacted with sera from individuals infected with subtype O. The subtype O antigen-containing kit produced a positive absorbence even when sera were diluted 512-fold, suggesting a high sensitivity. The commercially available kit also reacted with subtype O sera, but produced a negative result at a dilution of 8-fold. Our results suggest that the currently available kit may not be able to efficiently detect subtype O sera and that the viral protein developed in this study may be added to the current system to maximize the detection of sera from individuals infected with subtype O.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.10
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• pp.39-50
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• 1998

Wide-band sharp-transition filters are widely used in applications such as wireless CODEC design or medical systems. Since these filters suffer from large sensitivity and roundoff noise, large word-length is required for the VLSI implementation, which increases the hardware size and the power consumption of the chip. In this paper, a low-power implementation technique for digital filters with wide-band sharp-transition characteristics is proposed using CPL (Complementary Pass-Transistor Logic), LWDF (Lattice Wave Digital Filter) and a modified DIFIR (Decomposed & Interpolated FIR) algorithm. To reduce the short-circuit current component in CPL circuits due to threshold voltage reduction through the pass transistor, three different approaches can be used: cross-coupled PMOS latch, PMOS body biasing and weak PMOS latch. Of the three, the cross-coupled PMOS latch approach is the most realistic solution when the noise margin as well as the energy-delay product is considered. To optimize CPL transistor size with insight, the empirical formulas for the delay and energy consumption in the basic structure of CPL circuits were derived from the simulation results. In addition, the filter coefficients are encoded using CSD (Canonic Signed Digit) format and optimized by a coefficient quantization program. The hardware cost is minimized further by a modified DIFIR algorithm. Simulation result shows that the proposed method can achieve about 38% reductions in power consumption compared with the conventional method.

• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.21-27
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• 2016

The objectives of this study are to produce monoclonal antibodies (MAbs) against Vibrio parahaemolyticus and to develop an immuno-selective filtration (ISF) method for the rapid and sensitive detection of V. parahaemolyticus. The characterization of the MAb produced from HKVP 4H9-9 hybridoma cell was validated by enzyme-linked immunosorbent assay (ELISA) and western blot. The produced MAb was specific to V. parahaemolyticus and showed weak cross-reaction to V. alginolyticus, V. vulnificus and Staphylococcus aureus. After optimization of the method, $5{\times}10^1cell/mL$ of V. parahaemolyticus in a pure culture could be detectable. Although weak cross-reactivity to V. vulnificus, V. alginolyticus and Staphylococcus aureus was observed, the ISF was confirmed to be highly specific to V. parahaemolyticus. Especially, the ISF showed the most sensitivity compared to the immunoassays currently reported is easier to perform and quicker than ID-ELISA.

• Management & Information Systems Review
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• v.37 no.3
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• pp.65-81
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• 2018

This study estimated the long-run and the short-run price and income elasticity of crude oil demand by using the ARDL model in Korea. First, the long-run cointegration relationship existed between crude oil demand and price or income in the ARDL-bounds tests. Second, the long-run own price, the cross price elasticity and the income elasticity were both statistically significant elastic and sensitive in the ARDL. Third, there was autocorrelation of the residuals, but no misspecification errors and heteroscedasticity, and then the residuals showed a normal distribution. And the CUSUM & CUSUMSQ tests showed that the coefficients were stable. Fourth, the short-run own price, the cross price elasticity and the income elasticity were both statistically significant elastic and sensitive in the ARDL-RECM. The ECM with the short-run dynamics showed rapid adjustments in the long-run equilibrium of oil demand after the economic crisis. In the short-run, the sensitivity of crude oil demand to price and income changes has moved in the same direction as the long-run case. Korea, depending too much on foreign crude oil, is vulnerable to the shocks of oil prices, so rising oil prices can certainly have a negative impact on Korea's trade balance. And the elasticity of long-run oil prices may help to control and manage Korea's oil demand. The government needs to strengthen monitoring of the country's policies and market trends related to crude oil, establish strategies to customize national policies and market conditions, and strengthen active market dominance efforts through pioneering new market and diversification.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.52.2-52.2
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• 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is an unprecedentedly minimized infrared cross-dispersed echelle spectrograph with a high-resolution and high-sensitivity optical performance. A silicon immersion grating features the instrument for the first time in this field. IGRINS will cover the entire portion of the wavelength range between 1.45 and $2.45{\mu}m$ accessible from the ground in a single exposure with spectral resolution of 40,000. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is $1^{\prime\prime}{\times}15^{\prime\prime}$. IGRINS has a $0.27^{\prime\prime}$ pixel-1 plate scale on a $2048{\times}2048$ pixel Teledyne Scientific & Imaging HAWAII-2RG detector with SIDECAR ASIC cryogenic controller. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be 25mm, which permits the entire cryogenic system to be contained in a moderately sized rectangular vacuum chamber. The fabrication and assembly of the optical and mechanical hardware components were completed in 2013. In this presentation, we describe the major design characteristics of the instrument and the early performance estimated from the first light commissioning at the McDonald Observatory.

• Journal of Korea Water Resources Association
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• v.39 no.2 s.163
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• pp.151-160
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• 2006

In this study, threshold runoff which is a hydrologic component of flash flood guidance(FFG) is estimated by using Manning's bankfull flow and Geomorphoclimatic Instantaneous Unit Hydrograph(GcIUH) methods on Han River watershed. Geographic Information System(GIS) and 3' Digital Elevation Model database have been used to prepare the basin parameters of a very fine drainage area($1.02\~56.41km^2$), stream length and stream slope for threshold runoff computation. Also, cross-sectional data of basin and stream channel are collected for a statistical analysis of regional regression relationships and then those are used to estimate the stream parameters. The estimated threshold runoff values are ranged from 2 mm/h to 14 mm/6hr on Han River headwater basin with the 1-hour duration values are$97\%$ up to 8mm and the 6-hour values are $98\%$ up to 14mm. The sensitivity analysis shows that threshold runoff is more variative to the stream channel cross-sectional factors such as a stream slope, top width and friction slope than the drainage area. In comparisons between the computed threshold runoffs on this study area and the three other regions in the United States, the computed results on Han River watershed are reasonable.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.1-12
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• 2001

A competitive indirect enzyme-linked immunosorbent assay (ci ELISA) for the organophosphorus insecticide acephate, O,S-dimethyl acetylphosphoramidothioate, was developed using a polyclonal antibody. Three different haptens mimicking the analyze and containing hexanoic acid moiety as a linker were synthesized, and then conjugated with the carrier proteins bovine serum albumin and keyhole limpet hemocyanin by the N-hydroxysuccinimide active ester method. Polyclonal antibodies raised against hapten-KLH conjugates in rabbits and the hapten-BSA conjugates as coating antigens were screened and selected for the assay in the homologous and/or heterologous ELISA system. The effects of various assay conditions, including blocking reagents, detergent content, organic solvents, pH, and preincubation of tile mixture of the polyclonal antibody and the analyze on the sensitivity were evaluated. The $IC_{50}$ value of acephate of 110 ng/mL was obtained in an optimized heterologous system using hapten-3-BSA as a coating antigen and a polyclonal antibody 8377, showing the detection range of 10-1000 ng/mL and the lowest detection limit of 4 ng/mL. The cross-reactivities of the structurally related insecticides, including methamidophos were less than 0.02%. These results indicate that the ELISA could be a convenient and alternative tool for monitoring acephate residues in agricultural products and environmental samples.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.310-313
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• 2009

A single cross, Pyeonganok, is an yellow flint-like maize hybrid (Zea mays L.) developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2008. This hybrid, which has a high yield of dry matter was produced by crossing two inbred lines, KS140 and KS94. KS140 is the seed parent and KS94 is the pollen parent of Pyeonganok. Silking date of Pyeonganok is 3 days later than that of check hybrid, Kwangpyeongok. Stay-green of Pyeonganok is not greatly different with that of Kwangpyeongok. It has resistance to lodging. It has moderately resistance to Bipolaris maydis (southern corn leaf blight), Exserohilum turcicum (northern corn leaf blight), and corn borer but sensitivity to black streaked dwarf virus (BSDV). Pyeonganok was evaluated for the yields of dry matter at four locations from 2006 to 2008. The yields of Pyeonganok in dry matter was 20.84 ton/ha. Seed production of Pyeonganok has gone well due to a good match during crossing between the seed parent, KS140 and the pollen parent, KS94 in Yeongwol.