• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.4
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• pp.565-571
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• 2021

In this paper, a compensation scheme of frequency selective IQ mismatch for high-performance radar systems based on commercial RFIC's is proposed. Besides, an optimization model and its solution based on the dimension reduction scheme using singular value decomposition are also proposed to design the optimal IQ mismatch compensation digital filter with complex coefficients. The performance of the proposed method had been analyzed through experiments using the IQ mismatch measurement and compensation system implemented on an FPGA board with a target RFIC and compared with the previous method. The experiment result showed a performance improvement of the proposed method over the existing one without noticeable increments in complexities. These performance analysis results showed that the limitation of using commercial RFIC's in high-performance radar systems due to the undesirable maximum SNR cap caused by their IQ mismatches could be overcome by employing the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.4
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• pp.206-208
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• 2014

In this letter, IQ mismatch of a CA-supporting terminal for LTE-A is analyzed and each of the analog blocks is modeled mathematically. Based on the model, a new digital calibration algorithm is proposed and verified using simulation results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.67-71
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• 1997

Different concentrations of lignin and hemicellulose were preincubated with 0.01$\mu\textrm{g}$ of 2-amino-3-methylimidazo［4, 5-f］quinoline(IQ) at simulated gastrointestinal pH condition s. The Ames Salmonella assay using Salmonella typhimurim TA98 was performed to detect any changes in the mutagenicity of IQ in the presence of lignin or hemicellulose. IQ revealed very weak or no mutagenicity when it was preincubated at pH 2.1. However, there was a dose-dependent inhibition of IQ mutagenicity in tile presence of lignin or hemicellulose at pH 5.4 and 6.6. The antimutagenic activities of fibers were not different from each other. Also, at lower concentrations of fibers, pH 5.4 was more effective in suppressing IQ mutagenicity, while 300$\mu\textrm{g}$ of lignin or hemicellulose significantly reduced the mutagenicity of IQ regardless of pH conditions. These results suggest that at gastrointestinal pH conditions, both soluble and insoluble fibers inhibit mutagenicity of IQ by adsorption. Therefore, a possible mechanism for Protective effect of fibers against cancer is due to their adsorption to mutagens in the gastrointestinal tract, and pH seems to be an important factor in the regulation of interactions between the fiber and mutagens.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.5A
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• pp.341-346
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• 2009

M-WiMAX (Mobile-Worldwide Interoperability for Microwave Access) system, which uses OFDM (Orthogonal Frequency Division Multiplexing) technique, is known to be proper for mobile high-speed data transmission system. Nevertheless, M-WiMAX is seriously sensitive to IQ imbalance caused by the LO (Local Oscillator) at the receiver. In this paper, we analyze the effect of IQ imbalance on the system, and then propose a joint optimization scheme that can optimize DFE (Digital Front-end) of mobile modem by combining operation duplicated between AGC (Automatic Gain Control) and the estimation and compensation of IQ imbalance. Simulation results show that the proposed scheme achieves the same performance of the conventional scheme while reducing the complexity of the H/W implementation.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.1
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• pp.59-67
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• 2009

Objectives : This research aimed to evaluate the effects of Rubus coreanus $M_{IQ}$. Methods: These extracts from fresh R. coreanus $M_{IQ}$. were investigated with radical scavenging activity, the content of total phenolics, ferric thiocyanate method and flavonoid contents Results: These results revealed that the ethyl acetate extract from fresh R. coreanus $M_{IQ}$. possesses remarkable radical scavenging activity. The content of total phenolics of the ethanol extract from dried R. coreanus $M_{IQ}$. ($IC_{50}$=155.87${\pm}$8.8${\mu}$g/mL) is the highest among all of the samples. The stronger radical-scavenging activity ($IC_{50}$=77.72${\pm}$2.1${\mu}$g/mL) of ethyl acetate extract from dried R. coreanus $M_{IQ}$. should be related to its phenolic content as measured by gallic acid test. Conclusion: These results suggest that dried R. coreanus $M_{IQ}$. may act as a potential antioxidant agent.

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.152-156
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• 2014

Isoquercitrin (IQ), quercetin monoglycoside, is classified as a polyphenol, and a minute quantity of IQ is known to be present in several plants. Recently, it was reported that IQ can be prepared by the partial enzymatic hydrolysis of quercetin diglycoside (rutin, RU). In this paper, the effects of enzyme types, enzyme amounts, and substrate concentrations on the reactivity were investigated using a series of $Pecinex^{TM}$ multi-enzymes. The reaction, when a 8 ml of Ultra Clear to 1 g of RU was applied with the substrate concentration of 1% at $50^{\circ}C$, was found to be optimum, based on the reaction rate and the selectivity to IQ.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.3
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• pp.452-457
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• 2010

To obtain basic information on the utilization of Suaeda (S.) asparagoides $M_{IQ}$ as a raw material in food, it's chemical components of were investigated. S. asparagoides $M_{IQ}$ from the Hwaseong-si in Korea was used after drying and grinding with powder. The total dietary fiber, insoluble dietary fiber and soluble dietary fiber contents of S. asparagoides $M_{IQ}$ were found to be 39.41%, 37.63% and 1.78%, respectively. Macromineral components of S. asparagoides $M_{IQ}$ were Na (7.6%), K (2.4%) and Mg (0.6%). High contents of microminerals such as Cu, Mn and Zn were also found. Lysine and methionine which are essential amino acids were detected with the value of 215 mg/100 g and 23.2 mg/100 g, respectively. S. asparagoides $M_{IQ}$ that was harvested in May was higher in crude protein than that harvested in September but the crude fat content of that which was harvested in September was twice as high as that harvested in May.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1803-1810
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• 2009

This paper designed IQ imbalance estimator and compensator to cancel the IQ imbalance error in DVB-T system using OFDM by Matlab. Among Matlab model, we designed and implemented IQ imbalance estimator and compensator by System Generator of Xilinx and Matlab model compared with Xilinx System Generator Model for FPGA implementation. As a result of simulation, we confirmed that both model estimated and compensated IQ imbalance error very well. Also, we verified the performance through hardware co-simulation, timing analysis and resource estimation with Xilinx Spartan3 xc3s1000 fg676-4 target Device.

• Korean Journal of Health Education and Promotion
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• v.29 no.1
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• pp.73-87
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• 2012

Objectives: The purpose of this study was to examine the compositional fitness and independence of the original six dimensions and the newly-designed six dimensions of Integrated Questionnaire for the Measurement of Social Capital[SC-IQ], and to explore the more simplified version for convenient use in public health-related social capital studies. Methods: This study reanalyzed social capital items included in a 2004 community health survey of K-city conducted by Hallym Health Services Research Center. Data was collected from 1,000 adults using core questions of SC-IQ. Explanatory factor analyses to all questions were done, and the new six dimensions were established. Confirmatory factor analyses[CFA] were done on the original and new six dimensions. And then reliability and validity test were done. SPSS 15.0 and AMOS 7.0 were used. Results: The final CFA module to the new SC-IQ exhibited Root Mean Square Error of Approximation[RMSEA] 0.028 and only compositional fitness and independence, and was composed of four dimensions and eight questions, and covers all elements of social capital including structural, cognitive, operational, outcome, bonding and bridging elements. Conclusion: This study demonstrates the utility of a new, simplified version of SC-IQ as well as its convenience.

• Research in Community and Public Health Nursing
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• v.22 no.4
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• pp.377-388
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• 2011

Purpose: This study was to examine the relation between diabetes and cognitive function in older adults. Methods: Eighty community-dwelling patients with diabetes and 506 subjects without diabetes were studied with cognitive function test. Cognitive function was measured by Full-scale IQ, Basic IQ, Executive IQ, Attention Function Index, Working Memory Index, Language Function Index, Visuospatial Function Index, Memory Function Index, and MMSE-K1. Results: In model controlling for education, the diabetic group showed significantly lower scores than the non-diabetic group in in Full-scale IQ (p=.012), Basic IQ (p=.034), Executive IQ (p=.014), Attention Function Index (p=.002), Working Memory Index (p=.037), and Memory Function Index (p=.043). The diabetic and non-diabetic groups that were matched for gender, age, and education showed similar differences in 7 out of 9 cognitive measures. The impairments of Full-scale IQ and Memory Function Index in the diabetic group were, respectively, 2.7 and 2.8 times greater than that in the diabetic group. Conclusion: These results showed that diabetes should be considered to a factor of cognitive impairment in older adults.