• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.1
• /
• pp.72-80
• /
• 1997

A 750 MHz CATV amplifier module has been designed and fabricated using PHEMT chips on alumina board. Developed 2-stage push-pull amplifier using wire bounded PHEMT chips shows 19dB gain, 15dB return loss and 4. 2dB noise figure over 50-750MHz frequency range. These results are superior to the characteristics of the commer-cially abailable 750MHz amplifier module. In this paper, brief background of the amplifier design, the circuit diagram and the test result have been presented.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.113-114
• /
• 2006

In this paper, dual-gate mixer has been designed and optimized to have variable conversion gain for WiBro and WLAN applications and to save power. With the LO power of 0dBm and RF power of -50dBm, the mixer shows 15dB conversion gain. When RF power increases from -50dBm to -20dBm, the conversion gain decreases to -2dB with bias change. The variable conversion gain can reduce the high dynamic range requirement of AGC burden at IF stage. Also, it can save the dc power dissipation of mixer up to 90%.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.614-615
• /
• 2016

I studied electrical coupling of monolithic 3D inverter(M3D-INV) consisting of Junctionless FET(JLFET). If the thickness of Inter Layer Dielectric (ILD) between top JLFET and bottom JLFET is less than 50nm, current-voltage characteristic of top JLFET is rapidly changed by the gate voltage of bottom JLFET. Therefore, you have to consider about the electrical interaction according to the thickness between top JLFET and bottom JLFET in M3D-INV.

• Preventive Nutrition and Food Science
• /
• v.11 no.3
• /
• pp.210-217
• /
• 2006

This study was performed to investigate effects of the experimental mixture containing soybean peptides, L-carnitine and Garcinia Cambogia extract on body weight and lipid metabolism in rats. Male Sprague-Dawley rats (n=40) of eight weeks old were raised for four weeks with high fat diet (40% fat as calorie) to induce obesity. After induction of obesity, rats were feed control (C) diet, containing either 0.16% (+1D), 1.6% (+10D), 8% (+50D) of experimental mixture for eight weeks. Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity and total protein and albumin concentration were not different among groups. The Body weight gain was significantly lower in experimental mixture diet group compared to control group. Weights of perirenal fat pad and epididymal fat pad in the +50D group were significantly lower than those in the +1D and +10D groups. Plasma total lipid and liver total cholesterol levels in the experimental groups were significantly lower than those in the control group. Fecal total lipid and total cholesterol excretions were highest in +50D group. These results suggest that the experimental mixture containing peptides, L-carnitine and Garsinia Canbogia extract is effective for reducing the body weight and adipose tissue weight which may be due to the modulation of lipid metabolism and the increased fecal excretion of lipid.

• Journal of Navigation and Port Research
• /
• v.32 no.6
• /
• pp.453-458
• /
• 2008

Flow characteristics of the control-rod-attached 2-dimensional circular cylinder was accomplished using by PIV techniques. model tests had been carried out with different diameters of control rods(d/D=0.1 through d/D=0.5). and the Reynolds number Re=15,000 based on the cylinder diameter(D=50mm) to predict the performance of the model and the two-frame grey-level cross-correlation method had been used to obtain the velocity distribution in the flow field. 50mm circular cylinder had been used during the whole experiments and measured results had been compared with each other. The measured results have been compared with each case. therefore this article identifies not only the mean velocity profiles but also the control effects of the control rods.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.24 no.4
• /
• pp.403-412
• /
• 2021

Purpose: This study aimed to determine the serum 25-hydroxy-vitamin D (25(OH)D) status of breastfed infants less than six months old and their mothers, and factors affecting the status. Methods: This cross-sectional study was done on breastfed, term, Filipino infants less than six months old who were seen at local health centers and clinics in an urban area. The serum 25(OH)D levels of these infants and their mothers were determined, and their demographic data, nutritional status, sun exposure behavior, and maternal vitamin D intake were analyzed for correlation using regression models. Results: Among the 131 infants, 101 (77%) had vitamin D deficiency (VDD), which was defined as having 25(OH)D levels <37.5 nmol/L, and 13 (10%) had vitamin D insufficiency (VDI), with levels >37.5-50 nmol/L. Conversely, maternal VDD with levels <50 nmol/L was seen in 31 (24%) mothers and maternal VDI with levels 50-75 nmol/L, in 63 (48%) mothers. Infant age and maternal 25(OH)D status were independent predictors of infant VDD. Infants less than three months old were found to have a six-time increased risk of infant VDD (p=0.004). Infants who had mothers with VDD had a six-time increased risk, whereas those with maternal VDI had a four-time increased risk of infant VDD (p=0.049 and p=0.020, respectively). Conclusion: Both infant and maternal VDD and VDI were seen to be highly prevalent in this tropical, urban community. Young infants and maternal VDD/VDI independently increased the risk of infant VDD, whereas lack of sun exposure of the mothers increased the risk for maternal VDI.

• The Bulletin of The Korean Astronomical Society
• /
• v.28 no.1
• /
• pp.50-50
• /
• 2003

• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 2003.11a
• /
• pp.50-50
• /
• 2003

• Animal cells and systems
• /
• v.8
• /
• pp.50-50
• /
• 2004

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.5 no.2
• /
• pp.8-14
• /
• 1968

A linear current-pulse discriminator consisting: of a transistor monostable multivibrator and a Si tunnel diode is described. The input currant pulse range is about 50$\mu$A~5.23mA. The measured maximum linearity deviation is $\pm$0.75% in the input current pulse range mentioned above. The pulse resolving ability of the discriminator measured depends upon the bias current through the T, D. ; and, under the reverse bias current of 3mA, the resolving time is 2rs if allow the excess pulse amplitude of 5%. The threshold stability of the discriminator depends mainly upon the stability of the peak current Ip of the T. D. ; and, under the ambient temperature variation from $0^{\circ}C$ to 5$0^{\circ}C$, no bigger threshold variation than the maximum linearity deviation, i. e. $\pm$ 0.75%, was observed.