• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.231-236
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• 2005

This study was conducted to determine the amounts of pesticide residues after treatment of criterion dose with 4 pesticides(tolclofos-m, folpet, procymidone, and triflumizole) under cultivated period and to compare the biological half-life of pesticides with 6 kinetic models(first, zero and second order kinetics, power function, elovich and parabolic model) and to establish proposed field tolerance using biological half-lives. Recovery of 4 pesticides form strawberry was ranged from 85.1 to 105.5%. For all of 4 pesticides, dissipation rate was over 73% at 5 days after application. Among 6 kinetic models, first order kinetic model (FO) was best fit to describe the relationship between residual pattern of pesticides and time. Therefore, half-lives were calculated by FO for establishing the field tolerance. These results showed that half-life should be calculated by comparative best fit kinetic model and field tolerance can help to prevent unacceptable agricultural products from marketing. It is good for both consumers and farmers having safe agricultural products and financial benefits, respectively.

• Journal of IKEEE
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• v.22 no.4
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• pp.1025-1030
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• 2018

The proposed modulator is designed by utilizing a conventional structure employing time division technique to realize the 4th order delta-sigma modulator using one op-amp. In order to reduce the influence of KT/C noise, the capacitance in the first and second integrators reused was chosen to be 20pF and capacitance of third and fourth integrators was designed to be 1pF. The stage variable technique in the low power reconfigurable op-amp was used to solve the stability issue due to different capacitance loads for the reduction of KT/C noise. This technique enabled the proposed modulator to reduce the power consumption of 15% with respect to the conventional one. The proposed modulator was fabricated with 0.18um CMOS N-well 1 poly 6 metal process and consumes 305uW at supply voltage of 1.8V. The measurement results demonstrated that SNDR, ENOB, DR, FoM(Walden), and FoM(Schreier) were 66.3 dB, 10.6 bits, 83 dB, 98 pJ/step, and 142.8 dB at the sampling frequency of 256kHz, oversampling ratio of 128, clock frequency of 1.024 MHz, and input frequency of 250 Hz, respectively.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.6
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• pp.454-464
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• 2023

This paper proposes a low-power 8-bit asynchronous SAR ADC with a sampling rate of 1 MS/s for sensor node applications. The ADC uses bootstrapped switches to improve linearity and applies a VCM-based CDAC switching technique to reduce the power consumption and area of the DAC. Conventional synchronous SAR ADCs that operate in synchronization with an external clock suffer from high power consumption due to the use of a clock faster than the sampling rate, which can be overcome by using an asynchronous SAR ADC structure that handles internal comparisons in an asynchronous manner. In addition, the SAR logic is designed using dynamic logic circuits to reduce the large digital power consumption that occurs in low resolution ADC designs. The proposed ADC was simulated in a 180-nm CMOS process, and at a 1.8 V supply voltage and a sampling rate of 1 MS/s, it consumed 46.06 𝜇W of power, achieved an SNDR of 49.76 dB and an ENOB of 7.9738 bits, and obtained a FoM of 183.2 fJ/conv-step. The simulated DNL and INL are +0.186/-0.157 LSB and +0.111/-0.169 LSB.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.764-769
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• 2000

The lipase gene(lip) from Bacillus stearothermophilus was recombined in vitro by utilizing the DNA shuffling technique. After four rounds of shuffling, transformation, and screening based on the initial rate of clear zone formation on a tricaprylin plate, a clone (M10) was isolated, the cell extract of which showed about 2.8-fold increased lipase activity. The DNA sequence of the mutant lipase gene (m10) showed 3 base changes, resulting in two cryptic mutations and one amino acid substitution: S113($AGC{\rightarrow}AGT$), L252 ($TTG{\rightarrow}TTA$), and G275E ($GGA{\rightarrow}GAA$). SDS-PAGE analysis revealed that the increased enzyme activity observed in M10 was partly caused by high expression of the m10 lipase gene. The amount of the expressed G275E lipase was estimated to comprise as much as 41% of the total soluble proteins of the cell. The maximum velocity ($V_{max}$) of the purified mutant enzyme for the hydrolysis of olive oil was measured to be 3,200 U/mg, which was 10% higher than that of the parental (WT) lipase (2,900 U/mg). Its optimum temperature for the hydrolysis of olive oil was $68^{\circ}C$ and it showed a typical $Ca^{2+}$-dependent thermostability, properties fo which were the same as those of the WT lipase. However, the mutant enzyme exhibited a high enantiospecificity towards (S)-naproxen compared with the WT lipase. In addition, it showed increased hydrolytic activity towards triolein, tricaprin, tricaprylin, and tricaproin.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.6
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• pp.513-518
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• 2015

Salinity gradient power (SGP) has attracted significant attention because of its high potential. In this study, we evaluate reverse electrodialysis (RED) with various compositions of available resources. The polarization curve (I-V characteristics) shows linear behavior, and therefore the power density curve has a parabolic shape. We measure the power density with varying compartment thicknesses and inlet flow rates. The gross power density increases with decreasing compartment thickness and increasing flow rate. The net power density, which is the gross power density minus the pumping power, has a maximum value at a compartment thickness of 0.2 mm and an inlet flow rate of 22.5 mL/min. The power density in RED is also evaluated with compositions of desalination brines, seawater, river water, wastewater, and brackish water. A maximum power density of $1.75W/m^2$ is obtained when brine discharged from forward osmosis (FO) and river water are used as the concentrated and the diluted solutions, respectively.

• Journal of Photoscience
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• v.5 no.4
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• pp.169-174
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• 1998

Photosynthetic responses to dehydration were examined by the simulataneous measurement of O2 evolution and chlorophyll (Chl) fluorescence in green pepper leaves. Dehydration was induced by immersing the plant roots directly in the Hoagland solution containing varying concentration (2-30%) of polyethylene glycol(PEG-6000) . Water potential of the leaf was decreased time-and concentation -dependently by PEG-treatment. The decrease in water potential of leaf was correlated with the decrease in both the maximal photosynthesis (Pmax) and quantum yield of O2 evolution, but Pmax dropped more rapidly than quantum yield at all water deficit conditions tested. However, Chl fluorescence parameters were not affected much. Dehydration did not change the initial fluorescence (Fo) and maximum photochemical efficiency(Fv/Fm) of photosystem(PS) II. Both the photochemical quenching (qP) and non-photochemical quenching(NPQ) were not changed by dehydration under low PFR(50 $\mu$mols m-2s-1 ). In contrast, under high PFR(270$\mu$mols m-2s-1)qP was slightly decreased while NPQ was greatly increased. The fast induction kinetics of Chl fluroecence showed no change in Chl fluorescence pattern by dehydration at high PFR (640 $\mu$mols m-2s-1 ), but exhibited a significant drop in peak level(Fp)at low PRFR (70$\mu$mols m-2s-1 ). PS I oxidation and reduction kinetics revealed normal reduction but delayed oxidation to P-700+, suggesting no lesionin electron flow from PSII to PSI , but impaired electron transport to NADP+,These results suggest that water stress caused by PEG-treatment results in the reduction of photosynthesis, promarily due to the reducted electron trasport from PSI to NADP+ or hampered subsequent steps involving Calvin Cycle.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.760-770
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• 2016

A 12-bit 750 kS/s Dual-Sampling Successive Approximation Register Analog-to-Digital Converter (SAR ADC) technique with reduced Capacitive DAC (CDAC) is presented in this paper. By adopting the Adaptive Power Control (APC) technique for the two-stage latched type comparator and using bootstrap switch, power consumption can be reduced and overall system efficiency can be optimized. Bootstrapped switches also are used to enhance the sampling linearity at a high input frequency. The proposed SAR ADC reduces the average switching energy compared with conventional SAR ADC by adopting reduced the Most Significant Bit (MSB) cycling step with Dual-Sampling of the analog signal. This technique holds the signal at both comparator input asymmetrically in sample mode. Therefore, the MSB can be calculated without consuming any switching energy. The prototype SAR ADC was implemented in $0.18-{\mu}m$ CMOS technology and occupies $0.728mm^2$. The measurement results show the proposed ADC achieves an Effective Number-of-Bits (ENOB) of 10.73 at a sampling frequency of 750 kS/s and clock frequency of 25 MHz. It consumes only 0.13 mW from a 5.0-V supply and achieves the INL and DNL of +2.78/-2.45 LSB and +0.36/-0.73 LSB respectively, SINAD of 66.35 dB, and a Figures-of-Merit (FoM) of a 102 fJ/conversion-step.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.340-344
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• 1991

This study was investigated to find out the optimum planting densities fo Solanum njrum L. about growth characters. yield components and yield at 6 planting densities by direct sowing culture. The results obtained are summarized as follows: Studying the correlationship. the highly negative significances were found between planting densities and fresh eights weights per plant, on the other hand, the highly positive significances were found between planting densities and plant height. Plant height was long in dense planting, and short in spacious planting by direct sowing culture. Stem diameter was thick in spacious planting. and was thin in dense planting. Fresh wt. per plant was decreased in dense planting and was increased in spacious planting by direct sowing culture. Yield was highest in dense planting densities (10 x 20cm : 50plants/$m^2$) by direct sowing culture. Fertilizing ((N： P$_2$O$_{5}$ $K_2$O=6 : 6 : 6Kg/10a) was increased than without fertilizing because plant height and number of branch was good.d.

• Solar Energy
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• v.15 no.1
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• pp.3-11
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• 1995

Heat transfer phenomena during inward freezing process of the water in a horizontal cylinder were experimentally studied. The cooling temperature of a wall more significantly affects the timewise average temperature than the initial superheating temperature of the water. In addition, it was absolved that the timewise average temperature was influenced by the initial volume ratio of the water($V_l/V_{tot}$) at the same temperature conditons. One the other hand, the freezing speed of the upper part in the water-ice interface was quickly progressed due to natural convection. Furthermore, experimental observation showed that the frozen mass fraction($M_s/M_{tot}$) was influenced by the initial volume ratio of the water($V_l/V_{tot}$). It was noted that the frozen mass fraction for each $V_l/V_{tot}$ represented by $Ste^*$ and Fo.

• Korean Journal of Acupuncture
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• v.27 no.2
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• pp.95-105
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• 2010

Objectives : The purpose of this study is to investigate the effect of Bacillus-fermented Scutellariae Radix acupuncture solution (SB) on interleukin(IL) production in mouse macrophage stimulatedby lipopolysaccaride(LPS). Methods : Productions of interleukins were measured y High-throughput Multiplex Bead based Assay with Bio-plex Suspension Array System based on $xMAP^{(R)}$(multi-analyte profiling beads) technology. To begin with, cell culture supernatant was obtained after treatment with LPS(1 ${\mu}g/mL$) and SB for 24 hour. Then, it was incubated with the antibody-conj${\mu}g$ated beads for 30 minutes. And detection antibody was added and incubated for 30 minutes. After incubating for 30 minutes, Strepavidin-conjugated Phycoerythrin(SAPE) was then added. Incubating for another 30 minutes, the level of SAPE fluorescence was analyzed on Bio-plex Suspension Array System. Results : The results of the experiment are as follows. SB significantly inhibited the LPS-induced production of IL-3($9.15{\pm}0.35$ pg/mL) by $6.92{\pm}0.05,\;7.21{\pm}0.11,\;6.96{\pm}0.33,\;and\;7.45{\pm}0.74$ pg/mL at the concentration of 25, 50, 100, and 200 ${\mu}g/mL$ in mouse macrophage RAW 264.7 cells (p<0.05). SB significantly inhibited the LPS-induced production of IL-5($7.30{\pm}0.48$ pg/mL) by $6.50{\pm}0.29,\;6.30{\pm}0.25,\;6.30{\pm}0.25,\;and\;5.80{\pm}0.25$ pg/mL at the concentration of 25, 50 100, and 200 ${\mg}g/mL$ in RAW 264.7 cells (p<0.05). SB significantly inhibited the LPS-induced productiion of IL-9($17.26{\pm}0.19$ pg/mL) by $15.01{\pm}0.43$ pg/mL at the concentration of 25 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced productioh of IL-13($187.80{\pm}2.90$ pg/mL) by $152.80{\pm}4.25,\;172.80{\pm}3.97,\;162.10{\pm}6.67,\;and\;165.30{\pm}11.80$ pg/mL at the concentration fo 25, 50, 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced production of IL-17($18.30{\pm}0.95$ pg/mL) by $13.30{\pm}1.25,\;13.80{\pm}1.11,\;13.30{\pm}0.75,\;and\;14.00{\pm}1.08$ pg/mL at the concentration of 25, 50 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced production of IL-23($43.90{\pm}0.83$ pg/mL by $39.50{\pm}1.26,\;38.00{\pm}1.78,\;and\;39.60{\pm}2.49$ pg/mL at the concentration of 25, 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). Conclusions : These results suggest that SB has anti-inflammatory activity related with its inhibition of IL-3, IL-5, IL-13, IL-17, and IL-23 production in macrophages.