• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.4
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• pp.484-492
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• 2015

This paper proposes a PWM phase-shift circuit to make that the LED lighting system distributes the channel currents evenly for any number of LED strings by generating evenly phase-shifted PWM signals for multiple LED driver ICs. The evenly distributed channel currents reduce the peak current, the decoupling capacitor size, and EMI noise. The PWM phase-shift circuit makes an arbitrary degree of PWM phase-shift by using a resistor and a capacitor. It measures the RC delay once. It reduces the number of external resistors and capacitors by providing zero and 180 degree phase-shift modes requiring no resistor and capacitor. An LED driver IC with the PWM phase-shift circuit was fabricated with a $0.35{\mu}m$ BCDMOS process. The PWM phase-shift circuit receives a PWM signal of 50 Hz~20 kHz at $f_{CLK}=450kHz$ and it generates a $0{\sim}360^{\circ}$ phase-shifted PWM signal with $R=0{\sim}1.1M{\Omega}$ at C=1 nF and $f_{PWM}=1kHz$. The measured phase errors are 1.74~3.94% due to parasitic capacitances.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.170-175
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• 1980

A mass production of chestnut necessiates the development of economic long-term storage method. The main objective of this study was to confirm the technical aspect of the chestnut storage method which was developed by two year project and to review the method of commercial application. The chestnut used for the experiments were separated in brine $(5.5{\sim}6.0^{\circ}\:B{\acute{a}}ume)$ into matured and unmatured lots and fumigated with $CS_2$ at a 5 $lb/27\;m^3$ level for $25{\sim}30\;hrs.$ The chestnuts were packed in wooden boxes with sawdust (50% moisture) in the ratio of 1 : 1 by volume. The boxes were stored in the cold room $(1{\pm}1^{\circ}C,\;85{\sim}95%\;RH)$ and the cellar ($0{\sim}10^{\circ}C$, controlled only by circulating night cool air). The results obtained were as follows: 1. Fully matured chestnut could be successfully preserved $8{\sim}9\;months$ at a l0% decay level in the cold room and $4{\sim}5\;months$ months in cellar. 2. Immatured chestnuts wire inferior to the matured in storage stability. At the maximum storage period, its storage life was two months shorter. 3. The heat transfer equation of piled chestnuts with sawdust can be suggested as $T_{\infty}-T_0=(T_{\infty}-T_0){\cdot}10^{-t/320}$ and j and $f_h$ values were 1 and 320 min, respectively. 4. The chestnuts in the package of storage unit had longer shelf life than naked chestnut during the retail distribution at ambient temperature.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.123-134
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• 2022

Toll-like receptors (TLRs), as a part of innate immunity, plays an important role in detecting pathogenic molecular patterns (PAMPs) which are structural components or product of pathogens and initiate host defense systems or innate immunity. Precise negative feedback regulations of TLR signaling are important in maintaining homeostasis to prevent tissue damage by uncontrolled inflammation during innate immune responses. In this study, we identified and characterized the function of the pancreatic progenitor cell differentiation and proliferation factor (PPDPF) as a negative regulator for TLR signal-mediated inflammation in chicken. Bioinformatics analysis showed that the structure of chicken PPDPF evolutionarily conserved amino acid sequences with domains, i.e., SH3 binding sites and CDC-like kinase 2 (CLK2) binding sites, suggesting that relevant signaling pathways might contribute to suppression of inflammation. Our results showed that stimulation with polyinosinic:polycytidylic acids (Poly [I:C]), a synthetic agonist for TLR3 signaling, increased the mRNA expression of PPDPF in chicken fibroblasts DF-1 but not in chicken macrophage-like cells HD11. In addition, the expression of pro-inflammatory genes stimulated by Poly(I:C) were reduced in DF-1 cells which overexpress PPDPF. Future studies warrant to reveal the molecular mechanisms responsible for the anti-inflammatory capacity of PPDPF in chicken as well as a potential target for controlling viral resistance.