• 천문학논총
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• 제22권4호
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• pp.183-187
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• 2007

The detection and measurement of faint features in cometary image is generally troublesome due to the high value of the ratio of the brightness of the nucleus to the tail, the large size and low surface brightness of the coma and tail and the disturbing presence of field stars trails. The image processing is based on background removal by median filtering. Sample results are shown for the case study of comet 73P/Schwassmann-Wachmann 3.

• 대한의용생체공학회:의공학회지
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• 제17권4호
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• pp.507-514
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• 1996

The automated ECG diagnostic systems in hospital have a low P-wave detection capacity in case of some diseases like conduction block. The purpose of this study is to improve the P-wave detection ca- pacity using wavelet transform. The first procedure is to remove baseline drift by subtracting the median filtered signal from the original signal. The second procedure is to cancel ECG's QRS-T complex from median filtered signal to get P-wave candidate. Before we subtracted the templete from QRS-T complex, we estimated the best matching between templete and QRS-T complex to minimize the error. Then, wavelet transform was applied to confirm P-wave. In particular, haiti wavelet was used to magnify P-wave that consisted of low frequency components and to reject high frequency noise of QRS-T complex cancelled signal. Finally, p-wave was discriminated and confirmed by threshold value. By using this method, We can got the around 95.1% P-wave detection. It was compared with contextual information.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 춘계학술발표대회
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• pp.986-989
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• 2011

Reversible data hiding is a technique that can embed information into cover media (image, video, voice signal) and can recover the original cover media after extracting the embedded information. In this papa, we propose a new reversible data hiding methods that based on block median preservation and the image local characteristic. By using the median value of a block, a high payload can be got and by considering the image local characteristic, a lot of distortion can be avoided and a high PSNR can be got. In the experiment, our methods can generate better result than the previous reversible data hiding methods.

• Journal of Biosystems Engineering
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• 제34권1호
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• pp.30-36
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• 2009

This study was performed to determine the effect of drying conditions on the germination properties of rapeseed after seeds were dried under different drying conditions: $40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$ in combination with 30%, 45%, or 60% relative humidity. As analytic results, drying conditions had significant effects (P-value < 0.001) and drying temperature was considered as the main factor on the germination properties of rapeseed. When drying temperature increased or relative humidity decreased, the vigor rate and germination rate decreased, the median germination time increased. The maximum values of vigor rate and germination rate were 90% and 95.44%, and their minimum values were 60.17 and 75%, respectively. To ensure the standard germination rate of 85%. The appropriate drying zone was determined and the drying temperature should be less than $51.0^{\circ}C$, $54.5^{\circ}C$ and $58.7^{\circ}C$ at 30%, 45% and 60% RH, respectively. The values for median germination time varied from 2 to 4 days. The predicted models of germination rate, vigor rate, and median germination time were determined.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2197-2204
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• 2015

In recent years, medical image diagnosis has growing significant momentous in the medicinal field. Brain and lung image of patient are distorted with salt and pepper noise is caused by moving the head and chest during scanning process of patients. Reconstruction of these images is a most significant field of diagnostic evaluation and is produced clearly through techniques such as linear or non-linear filtering. However, restored images are produced with smaller amount of noise reduction in the presence of huge magnitude of salt and pepper noises. To eliminate the high density of salt and pepper noises from the reproduction of images, a new efficient fuzzy based median filtering algorithm with a moderate elapsed time is proposed in this paper. Reproduction image results show enhanced performance for the proposed algorithm over other available noise reduction filtering techniques in terms of peak signal -to -noise ratio (PSNR), mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), image enhancement factor (IMF) and structural similarity (SSIM) value when tested on different medical images like magnetic resonance imaging (MRI) and computer tomography (CT) scan brain image and CT scan lung image. The introduced algorithm is switching filter that recognize the noise pixels and then corrects them by using median filter with fuzzy two-sided π- membership function for extracting the local information.

• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4125-4128
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• 2014

The median ages at death from cancers between 1985 and 2005 were calculated to demonstrate that inherent anticancer mechanisms may be a common pathway for different cancers. Seventy-eight patients with gastric, liver and lung cancers, were recruited in the solid cancer group. The leukemia group consisted of 31 patients with three main types of leukemia. The controls were 100 healthy individuals. The samples were typed using an HLA-DR/DQ PCR-SSP typing kit. The results showed that the median ages at death from all causes were 64.7 years in 1985 and 70.1 years in 2005. The range of the median ages at death from all cancers was similar to the corresponding value for deaths attributed to all causes. The frequency of $DRB1^*03$ was 9.6% in the solid cancer group and 3.0% in the control group (p<0.05). The frequency of $DRB1^*04$ in the leukemia group were significantly lower than that of the control (p<0.05). $DRB1^*13$ and $DRB1^*06$ frequencies in the leukemia group were significantly higher than those of the controls (p<0.05). It is suggested that inherent anti-cancer mechanisms may be a common pathway for different cancers and are associated with the immune system and HLA.

• Journal of Electrical Engineering and Technology
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• 제13권3호
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• pp.1383-1391
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• 2018

A new nonlinear filtering algorithm for effectively denoising images corrupted by the random-valued impulse noise, called dual sliding statistics switching median (DSSSM) filter is presented in this paper. The proposed DSSSM filter is made up of two subunits; i.e. Impulse noise detection and noise filtering. Initially, the impulse noise detection stage of DSSSM algorithm begins by processing the statistics of a localized detection window in sorted order and non-sorted order, simultaneously. Next, the median of absolute difference (MAD) obtained from both sorted statistics and non-sorted statistics will be further processed in order to classify any possible noise pixels. Subsequently, the filtering stage will replace the detected noise pixels with the estimated median value of the surrounding pixels. In addition, fuzzy based local information is used in the filtering stage to help the filter preserves the edges and details. Extensive simulations results conducted on gray scale images indicate that the DSSSM filter performs significantly better than a number of well-known impulse noise filters existing in literature in terms of noise suppression and detail preservation; with as much as 30% impulse noise corruption rate. Finally, this DSSSM filter is algorithmically simple and suitable to be implemented for electronic imaging products.

• Asian Pacific Journal of Cancer Prevention
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• 제16권11호
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• pp.4515-4520
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• 2015

GELOX (gemcitabine, oxaliplatin and L-asparaginase) regimen showed an impressive result in our previous study, but the effect of this new regimen is still dissatisfying for some patients, so it is necessary to identify which patients will benefit from this regimen. A total of fifty-one cases with nasal natural killer/T-cell lymphoma receiving initial GELOX chemotherapy were enrolled in this study. The ki-67 expression detected by immunohistochemistry (IHC) in the specimens ranged from 10% to 90%, with a median value of 70%, so cases higher than the median value (${\geq}70%$) were defined as high ki-67 expression, and the others were designated as low ki-67 expression. The response rate had no statistical difference between low ki-67 expression group and high ki-67 expression group (P=0.291) though the value in the former group was relatively high. After a median follow-up of 18.03 months, the 3-year progression-free survival (PFS) for patients with low ki-67 expression was significantly higher than those with high ki-67 expression (83.8% vs. 47.9%, P=0.038). In the stage I/II subgroup, 3-year PFS and overall survival (OS) were statistically higher in the patients with low ki-67 expression than those with high ki-67 expression. Multivariate analysis revealed high ki-67 expression was an independent prognostic factor for PFS. These results suggest that low ki-67 expression can predict a good response of GELOX in these patients, and the combination of ki-67 expression and early stage is helpful to identify an excellent prognosis subgroup from patients receiving GELOX in this disease.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1667-1670
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• 2014

Background: Calprotectin in feces seems to be a more sensitive marker for gastrointestinal (GI) cancers than fecal occult blood, but its specificity may be too low for screening average risk populations. This study aims at evaluating the diagnostic value of fecal calprotectin as a screening biomarker for GI malignancies. Materials and Methods: In a case-control study, 100 patients with GI malignancies (50 patients with colorectal cancer and 50 patients with gastric cancer) and 50 controls were recruited in Tabriz Imam Reza and Sina hospitals during a 24-month period. One to two weeks after the last endoscopy/colonoscopy, fecal specimens were collected by the patients and examined by ELISA method for quantitative measurement of calprotectin content. The results were compared between the three groups. Results: The mean fecal calprotectin level was $109.1{\pm}105.3$ (2.3-454.3, median:74), $241.1{\pm}205.2$ (3.4-610.0, median:19.3) and $45.9{\pm}55.1{\mu}g/g$ (1.3-257.1, median:19.3) in gastric cancer, colorectal cancer and control group, respectively, the differences being significant (p<0.001) and remaining after adjustment for age. The optimal cut-off point for fecal calprotectin was ${\geq}75.8{\mu}g/g$ for distinguishing colorectal cancer from normal cases (sensitivity and specificity of 80% and 84%, respectively). This value was ${\geq}41.9{\mu}g/g$ for distinguishing gastric cancer from normal cases (sensitivity and specificity of 62%). Conclusions: Our results revealed that fecal calprotectin might be a useful and non-invasive biomarker for distinguishing colorectal cancer from non-malignant GI conditions. However, due to low sensitivity and specificity, this biomarker may not help physicians distinguishing gastric cancer cases from healthy subjects.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제15권1호
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• pp.38-43
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• 2012

Purpose: Epstein-Barr virus (EBV) hepatitis is a usually asymptomatic and self-limiting disease in immunocompetent patients. However, the range of severity is wide, and the serological diagnosis is typically difficult until the convalescent phase. Thus, we examined the value of plasma EBV DNA real-time quantitative polymerase chain reaction (RT-qPCR) in EBV hepatitis for the timely diagnosis and the relationship between EBV viral load and clinical severity. Methods: Sixty samples were confirmed as having EBV infection by RT-qPCR with the EBV BALF5 gene sequence. We examined the clinical characteristics of EBV hepatitis by reviewing medical records. Results: The median total duration of fever was 8 days (range: 0-13 days). The mean peak value of aspartate aminotransferase (AST) was $241{\pm}214$ U/L, and the mean peak value of alanine aminotransferase (ALT) was $298{\pm}312$ U/L. There was no correlation between the serum levels of liver enzyme and plasma EBV DNA titer ($p$=0.1) or between median total duration of fever and EBV DNA titer ($p$=0.056). The median age of the EBV VCA IgM-negative group was lower compared with the EBV VCA IgM-positive group in EBV hepatitis (2 years vs. 6 years, $p$=0.0009). Conclusion: The severity of EBV hepatitis does not correlate with circulating EBV DNA load according to our data. Furthermore, we suggest that plasma EBV PCR may be valuable in young infants in whom the results of serology test for EBV infection commonly are negative.