• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.8
• /
• pp.1159-1168
• /
• 1993

The Switched-Capacitor Integrator(SCI) is a basic building block of Switched-Scpacitor Filter(SCF). But owing to the errors from the finite gain and bandwidth of op-amp on SCI, the most of SCP are limited to their applications. Although many of the compensation methods developed for active RC filters can be directly adapted to SCF, this is not true for the analysis of the effects of the op-amp dynamics on the filter response. The effect of finite op-amp gain is similar to the active RC filters. But SCF is more toter-ant of the finite op-amp bandwidth. In this paper, we have considered the errors of the finite gain and bandwidth of op-amp on SCI , and presented the simple and effective methods of compensating the errors of SCI due to the finite op-amp gain using the buffer circuit.

• Ocean Systems Engineering
• /
• v.13 no.1
• /
• pp.43-55
• /
• 2023

In this study, the SCFs in tubular T-joints stiffened with external ring under axial load are studied and discussed. After verification of the present numerical model with the results of several available experimental tests, 156 FE models were generated and analyzed to parametrically evaluate the effect of the joint geometry and the ring geometry on the SCFs. Results indicated that the SCF of the stiffened T-joints at crown point can be down to 24% of the SCF of the corresponding un-reinforced joint at the same point. Also, the effect of the ring on the SCF at saddle point is more remarkable than the effect of the ring on the SCF at crown point. Moreover, against un-reinforced joints under axial load, the SCF at saddle point of the stiffened joint is smaller than the SCF at crown point of that stiffened joint. The ring results in the redistribution of stresses in the ring and metal substrate. Also, the effect of the ring thickness on the decrease of the SCFs is slight and can be ignored. In final step, the geometric parameters affecting the SCFs of the stiffened T-joints are analyzed by multiple nonlinear regression analyses. An accurate formula is proposed for determining the SCFs.

• Journal of Industrial Technology
• /
• v.16
• /
• pp.191-195
• /
• 1996

This paper deals with the tapped time delay circuit with SCF(Switched Capacitor Filters). This filter is composed of lossless discrete integrator and the SCF has 2-phase clocks. Experimental results have shown that telephone signals (0~4kHz) could be delayed in the range of sampling frequency 80kHz. But above the range, operational amplifiers and analog switchs have been difficult in the normal operating condition.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.27 no.9
• /
• pp.1436-1441
• /
• 1990

Prototype Switched Capacitor 4th order Low pass and Band Pass Filters were Realized and tested. Their capacitor values were determined by using automatic SCF design tool. Each filter was designed to operate in voiceband frequency, and practical solutions to improve its frequency characteristics were given. Experimental results show the validity of automatic SCF design program. Simulation and experimental results were fully compared and optimum design conditions were summarized.

• Microbiology and Biotechnology Letters
• /
• v.44 no.1
• /
• pp.40-47
• /
• 2016

This study was conducted to evaluate the possible utility of 3 Aspergillus oryzae strains (designated as SCF-6, SCF-37, and JJSH-1), isolated from Korean traditional fermented materials, as starter cultures in the soybean paste industry. Doenjang (fermented soybean paste) was made with the A. oryzae strains described above, and its quality attributes were analyzed during a 60-day aging period. No significant differences in pH, moisture, or salt content were detected among the doenjang varieties made with the 3 Aspergillus strains. The concentration of amino-nitrogen, an indicator of doenjang aging, increased in each sample during the aging period. After the 60-day aging period, the contents of amino-nitrogen and free amino acid in doenjang made with SCF-6 showed the highest concentrations among the tested doenjang products: 971.6 and 8,064.9 mg%, respectively. Measurements of the color of doenjang showed that lightness and yellowness decreased during the aging period, but redness increased. After the 60-day aging period, the ${\gamma}$-aminobutyric-n-acid (GABA) concentrations in doenjang made with SCF-6 and SCF-37 were 61.3 and 53.7 mg%, respectively. In doenjang samples, aflatoxin was not detected and the concentrations of biogenic amines (histamine and tyramine) were 2.55-5.60 mg/kg and 3.70-5.87 mg/kg, respectively. These results indicated that A. oryzae SCF-6 isolated from traditional fermented foods could be useful as a starter culture in the soybean paste industry.

• Korean Journal of Food Science and Technology
• /
• v.51 no.2
• /
• pp.141-146
• /
• 2019

Sparassis crispa is an edible mushroom that is distributed in Korea, Japan, Europe, and North America. It exerts various biological activities such as immunopotentiation, anti-diabetic, anti-cancer, and anti-inflammatory effects. Recently, we separated the health functional non-aqueous fraction from the chloroform extract of S. crispa (SCF4). In this study, we evaluated the antiangiogenic activity of SCF4 in human umbilical vein endothelial cells (HUVECs). SCF4 effectively inhibited vascular endothelial growth factor (VEGF)-induced cell growth at concentrations ($5-25{\mu}g/mL$) showing no cytotoxic effects. SCF4 inhibited VEGF-induced invasiveness and tube formation ability, which are in vitro angiogenic features of HUVECs, in a dose-dependent manner. In addition, SCF4 markedly suppressed in vivo angiogenesis of chorioallantoic membrane from growing chick embryos without cytotoxicity. Furthermore, SCF4 downregulated the phosphorylation of VEGFR2, AKT, and ERK1/2, which are major angiogenic signal mediators. These results suggest that SCF4 inhibited angiogenesis by suppressing the VEGFR2 signaling pathways without cytotoxicity.

• Journal of Korean Academy of Nursing
• /
• v.40 no.2
• /
• pp.247-254
• /
• 2010

Purpose: To study the thickness of gluteal subcutaneous fat (SCF) and propose an adequate length for needle for gluteal intramuscular injections based on computed tomography (CT) measurements. Methods: The thickness of gluteal SCF were measured and studied for 568 patients who visited a tertiary hospital in Seoul, Korea between January 2007 and February 2009 for routine health screening and who had abdominopelvic CT. Results: The average thickness of gluteal SCF was $15.92{\pm}4.08mm$ in males and $24.90{\pm}5.47mm$ in females. The thickness of gluteal SCF differed significantly according to gender. The gluteal SCF thickness was greater than 20.4 mm for 54 (12.3%) of the 440 male patients and 99 (77.3%) of the 128 female patients. Conclusion: The most common syringe needle used for gluteal intramuscular injections in Korea is a 23 G, 25.4 mm-needle. The SCF thickness must be less than 20.4 mm in order to reach the dorsogluteal muscles to a depth of at least 5 mm if this 25.4 mm needle is used. In many patients, especially in female patients, the 25.4 mm needles will result in improper intramuscular injections with the injection being into the SCF. Therefore an appropriate needle should be selected by considering the gender and SCF thickness of patients receiving gluteal intramuscular injections.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.630-632
• /
• 2003

In this paper, we present the fabrication and performance of FBAR filters with ladder and stacked crystal filter (SCF) types. The structure of the unit resonator in our work is the solidly mounted resonator (SMR) with W/SiO$_2$ multi-layer reflectors, the return loss of of which show -24dB at resonant frequency of -2.0GHz. The $K^2$eff, Q$_{s}$, and Q$_{p}$, indicating the performance of resonator were 3.24%, 6,363 and 6,749 and were calculated for the resonator with the resonance area of 21200${\mu}{\textrm}{m}$$^2$. Based on this unit resonator, FBAR filters with ladder and SCF types were fabricated and compared. The sizes of filters were 800$\times$2000(${\mu}{\textrm}{m}$$^2$) for the ladder type and 600$\times$500(${\mu}{\textrm}{m}$$^2$) for the SCF type.e..

• The Transactions of the Korea Information Processing Society
• /
• v.2 no.5
• /
• pp.655-666
• /
• 1995

Advanced Intelligent Network(AIN) and X.500 directory service have similarity in between. X.500 capabilities and the requirements for the Service Control Function(SCF) to Service Data Function(SDF) in AIN. As an interface, SCF can be mapping as a Directory User Agent(DUA) and SDF can be mapping as a Directory System Agent(DSA). Based on the concepts, X.500 directory can be applied to AIN. In this paper we suggest to apply the X.500 DSP to the SDF/SDF interface to perform a distribution function. Also we show that the SCF-SDF/SDF-SDF relationship can be possible under applying X.500 DAP/DSP within the set of Capability Set 1 (CS1),CS2 and CS3. Finally, based on the above contents, we introduce the designed schematic of AIN SDF Server System for a distributed processing in AIN and design the X.500 schema of Universal Personal Telecommunication(UPT) service for supporting AIN SDF Server.

• International Journal of Contents
• /
• v.3 no.2
• /
• pp.35-39
• /
• 2007

The cognitive radio communication is taking the attentions because the development of the technique came to be possible to analyze wireless signals. In the IEEE 802.22 WRAN Systems[1], how to detect a spectrum and signals is continuously studied. In this paper, we propose the efficient signal detection method using SCF (Spectral Correlation Function). It is easy to detect the signal feature when we are using the SCF. Because most modulated signals have the cyclo-stationarity which is unique for each signal. But the fading channel effected serious influence even though it detects the feature of the signal. We applied LMS(Least Mean Square) filter for the compensation of the signal which is effected the serious influence in the fading channel. And we analyze some signal patterns through the SCF. And we show the unique signal feature of each signal through the SCF method. It is robust for low SNR(Signal to Noise Ratio) environment and we can distinguish it in the fading channel using LMS Filter.