• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.3 s.309
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• pp.34-42
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• 2006

In general, almost information is stored in only a few wavelet coefficients. This sparse characteristic of wavelet coefficient can be modeled by the mixture of Gaussian probability density function and point mass at zero, and denoising for this prior model is peformed by using Bayesian estimation. In this paper, we propose a method of parameter estimation for denoising using hypothesis-testing problem. Hypothesis-testing problem is applied to variance of wavelet coefficient, and $X^2$-test is used. Simulation results show our method outperforms about 0.3dB higher PSNR(peak signal-to-noise ratio) gains compared to the states-of-art denoising methods when using orthogonal wavelets.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.12
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• pp.1544-1553
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• 1999

Recently, ultrasonic testing techniques have been widely used in the evaluation of the quality of metal. In this experiment, six heat-treated temperature of specimen have been considered : 0, 1200, 1250, 1300, 1350 and 1387$^{\circ}C$. As heat-treated temperature increases, the grain size of stainless steel also increases and then, eventually make it destroy. In this paper, a pattern recognition method is proposed to identify the heat-treated temperature of metals by evidence accumulation based on artificial intelligence with multiple feature parameters; difference absolute mean value(DAMV), variance(VAR), mean frequency(MEANF), auto regressive model coefficient(ARC), linear cepstrum coefficient(LCC) and adaptive cepstrum vector(ACV). The grain signal pattern recognition is carried out through the evidence accumulation procedure using the distances measured with reference parameters. Especially ACV is superior to the other parameters. The results (96% successful pattern classification) are presented to support the feasibility of the suggested approach for ultrasonic grain signal pattern recognition.

• Child Health Nursing Research
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• v.8 no.3
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• pp.272-280
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• 2002

Purpose: This study was conducted to test the reliability and validity of Family Burden Questionnaire. Method: The subjects were 156 caregivers of children with acute or chronic disease. To test the reliability, internal consistency using Cronbach's α coefficient was analyzed, and factor analysis, known-group technique, and concurrent validity were utilized for validity test. Result: Cronbach's α coefficient of the tool was .89. Six factors were identified and explained 58.7% of the total variance. Through analysis using known-group technique, the difference of family burden between acute and chronic disease groups was statistically significant(t= -4.09, p<.001). Correlations with mood state, other family burden score by Family Burden Interview Schedule, quality of life, and health symptoms were also relatively high and statistically significant. Conclusion: Family Burden Questionnaire showed a relatively high validity and reliability to measure the burden of caregivers caring patients with various chronic conditions in Korea. For the further study, it may be reconsidered to identify the factor structure of the Family Burden Questionnaire with the various subjects from different age groups.

• Korean Parent-Child Health Journal
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• v.2
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• pp.64-82
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• 1999

This study was conducted to test the reliability and validity of Maternal Self-Report Inventory that was developed by Shea and Tronick for measuring maternal self-esteem. The subjects were 154 mothers. The construct validity for the scale was tested by factor analysis with five factor loading solution based on the previous study. One item was excluded because total-item correlation was too low, so that the number of total items were twenty-five, the analysis yielded five well defined factors: confidence on the maternal role, general ability of maternal role, caretaking ability, readiness on maternal role, and feeling on the pregnancy and deli very. These five factors explained 52.38% of the variance in the maternal self-esteem. Maternal self-esteem was not affected by maternal age, educational level, occupation, religion, delivery type, or parity. The reliability of the scale was determined with Cronbach's alpha coefficient and Guttman split-half coefficient. Cronbach's alpha was .82, for 26 items, and .83 if one item was deleted. Guttman split-half cofficient was .75. In subscale analysis, Cronbach's alpha was .63~.84. In conclusion. Maternal Self-Report Inventory showed a high degree of validity and reliability, suitable in Korean mothers for measuring maternal self-esteem. In the further study, it would be necessary to compare the maternal self-esteem between mothers with normal babies and premature babies, for confirming the criterion-related validity of the inventory.

• Journal of muscle and joint health
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• v.17 no.2
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• pp.183-191
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• 2010

Purpose: The purpose of this study was to test the validity and reliability of the Diabetes Self-Care Barriers Assessment Scaler for Older Adults (DSCB-OA) in Korean older adults with type 2 diabetes. Method: To develop Korean version DSCB-OA used translation and back-translation method. Then, Korean version DSCB-OA was analyzed using data of 278 older adults with type 2 diabetes. Cronbach's alpha coefficient, item to total correlation and test-retest reliability was used for the reliability test, and factor analysis was used for the construct validity. Results: Cronabach's alpha of the DSCB-OA was.77, and item to total correlation coefficient ranged from -.13 to.56. The results of factor analysis showed DSCB-OA consisted of four factors(diet, exercise, blood sugar test, treatment) which explained 62.8% of total variance. Conclusion: The Diabetes Self-Care Barriers Assessment Scaler for Older Adults (DSCB-OA) was confirmed helpful tool for Korean older adults with type 2 diabetes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.103-107
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• 2000

The viviparity of 28 rice varieties was tested at 25 days after heading(DAH), 35DAH, and 45DAH in the laboratory and field condition for 12 days. The incubation temperature was 20/l$0^{\circ}C$ (day/night), 25/15$^{\circ}$C$ and 30/20$^{\circ}$C$ in the laboratory test, and under field water conditions in the field test. The biggest varietal difference of viviparity was found in the laboratory test when examined at 45DAH with the 6-day incubation under 25/15$^{\circ}$C$ . At this conditions the mean viviparous ratio was 32.1 % with the range of 53.9 and the variance of 259.5. In the field test, the significant varietal difference in the viviparity was also found in the lodging treatment at 45 DAH for 6 days. Correlation coefficient analysis between the field and laboratory tests was highly significant from 4 days after incubation at 45 DAH and after 6-day incubation at 35 DAH, and correlation coefficient was higher as incubation days in the laboratory and submerged days under field water became longer. Considering the correlation between the field and laboratory tests, varietal difference of viviparity and convenience of testing, the laboratory test at 45 DAH for 6-day incubation under 25/15$^{\circ}$C$ was the most efficient evaluation method for the viviparity of rice cultivar.

• Mass Spectrometry Letters
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• v.4 no.1
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• pp.18-20
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• 2013

Headspace solid phase micro-extraction gas chromatography/flame ionization detection (HS-SPME-GC/FID) method was compared with headspace gas chromatography/mass selective detection (HS-GC/MS). Organic solvent-spiked urine as well as urine samples from workspace was analyzed under optimal condition of each method. Detection limit of each compound by HS-SPME-GC/FID was $3.4-9.5{\mu}g/L$, which enabled trace analysis of organic solvents in urine. Linear range of each organic solvent was $10-400{\mu}g/L$, with fair correlation coefficient between 0.992 and 0.999. The detection sensitivity was 4 times better than HS-GC/MS in selected ion monitoring (SIM) mode. Accuracy and precision was confirmed using commercial reference material, with accuracy around 90% and precision less than 4.6% of coefficient of variance. Among 48 urine samples from workplace, toluene was detected from 45 samples in the range of $20-324{\mu}g/L$, but no other solvents were found. As a method for trace analysis, SPME HS GC/FID showed high sensitivity for biological monitoring of organic solvent in urine.

• Korean Parent-Child Health Journal
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• v.4 no.2
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• pp.32-42
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• 2002

This study was conducted to test the reliability and validity of "What my baby is like(WBL)" that was developed by Pridham et al. for measuring infant temperament. 37 subjects were participated four times-1, 3, 6, and 12months, and 146 cases were analyzed. The construct validity for the scale was tested by factor analysis with four factor loading solution based on the previous study. One item was excluded because total-item correlation was too low, so that the number of total items were eighteen. The analysis yielded four well defined factors: amenability and persistence, activity, reactivity, and adaptability. These four factors explained 57.62% of the variance in the infant temperament. The criterion related Validity was confirmed by the relationship between the infant temperament and HOME, and between the infant temperament maternal confidence in childrearing. The reliability of the scale was determined with Cronbach's alpha coefficient and Guttman split-half coefficient. Cronbach's alpha was .86, for 18 items, and Guttman split-half cofficient was .81. In subscale analysis, Cronbach's alpha was .56~.84. In conclusion, WBL showed a high degree of validity and reliability, suitable in Korean infants for measuring temperament. In the further study, it would be necessary to refine the concept of temperament and to analyze the correlation between WBL and other temperament inventory.

• The Journal of the Acoustical Society of Korea
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• v.18 no.7
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• pp.101-111
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• 1999

This paper presents concrete pattern recognition method to identify the strength of concrete by evidence accumulation with multiple parameters based on artificial intelligence techniques. At first, variance(VAR), zero-crossing(ZCR), mean frequency(MEANF), and autoregressive model coefficient(ARC) and linear cepstrum coefficient(LCC) are extracted as feature parameters from ultrasonic signal of concrete. Pattern recognition is carried out through the evidence accumulation procedure using distance measured with reference parameters. A fuzzy mapping function is designed to transform the distances for the application of the evidence accumulation method. Results(92% successful pattern recognition rate) are presented to support the feasibility of the suggested approach for concrete pattern recognition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.7
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• pp.643-649
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• 2013

In this paper, human heartbeat detection using signal reflected from the antenna which is varied reflection coefficient by near field variation of the antenna. For detection reflected signal from antenna, 20 dB directional coupler is used because of not affecting transmitting signal. Variance of reflection coefficient of dipole antenna is about 0.07 dB which is too small the distinction between heartbeat and noise. Sensitivity increasing method is applied and heartbeat is clearly detected. Due to phase and magnitude errors come from discrete value components, antenna is located some points in experiments ro find optimum sensitivity position. And providing verification of using communication signal, heartbeat detection when frequency modulated signal which have 4 MHz bandwidth is applied.