• 제목/요약/키워드: Median value

검색결과 812건 처리시간 0.027초

Wavelet Transform을 이용한 P파 검출에 관한 연구 (P-wave Detection Using Wavelet Transform)

  • 윤영로;장원석
    • 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.

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Reversible Data Hiding Based on Block Median Preservation and image local characteristic

  • Qu, Xiao-Chao;Kim, Hyoung-Joong
    • 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.

유채종자의 건조조건에 따른 발아특성 (The Effects of Drying Conditions on the Germination Properties of Rapeseed)

  • ;한재웅
    • 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.

Enhancing Medical Images by New Fuzzy Membership Function Median Based Noise Detection and Filtering Technique

  • Elaiyaraja, G.;Kumaratharan, N.
    • 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.

Changes in Median Ages at Death from Selected Cancer Types in Relation to HLA-DRB1/DQB1

  • An, Wan-Xin;Fan, Ya-Xin;Liang, Xiao-Hua;Liu, Hui
    • 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.

Dual Sliding Statistics Switching Median Filter for the Removal of Low Level Random-Valued Impulse Noise

  • Suid, Mohd Helmi;Jusof, M F.M.;Ahmad, Mohd Ashraf
    • 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.

Ki-67 Can Predict the Response to the Gemcitabine, Oxaliplatin And L-asparaginase Regimen (GELOX) and Prognosis in Patients with Nasal Natural Killer/T-cell Lymphoma

  • Zhang, Jing;Jiang, Wei;Wang, Wei-Da;Liu, Cheng-Cheng;Hu, Yan-Ping;Xia, Zhong-Jun
    • 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.

Diagnostic Value of Fecal Calprotectin as a Screening Biomarker for Gastrointestinal Malignancies

  • Khoshbaten, Manouchehr;Pishahang, Parinaz;Nouri, Mohammad;Lashkari, Alireza;Alizadeh, Mahasti;Rostami-Nejad, Mohammad
    • 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.

Plasma Real Time-Quantitative Polymerase Chain Reaction of Epstein-Barr Virus in Immunocompetent Patients with Hepatitis

  • Hong, Ji-Hye;Bae, Yon-Jung;Sohn, Joon-Hyung;Ye, Byung-Il;Chun, Jin-Kyong;Kim, Hwang-Min
    • 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.

아동용 교우관계문제검사의 개발과 타당화 (Development and Validation of Inventory of Peer Relation Problems for Elementary School Children)

  • 정혜원
    • 초등상담연구
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    • 제7권1호
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    • pp.37-66
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    • 2008
  • This study has been carried out with the aims of developing a comprehensive inventory of peer relation problems, which is based on the Korean Inventory of Interpersonal Problems Circumplex scales (KIIP-C). It also aims to examine reliability and validity of the inventory, and provide a preliminary norms. For the current study, inventory items were culled from the following sources: the Korean Inventory of Interpersonal Problems Circumplex scales (KIIP-C), various current scales dealing with peer relations of children, and a survey of children's peer relation problems. The preliminary items for each scale were administered to 220 fourth through sixth graders. The resulting skewness of distribution, kurtosis, mean and standard deviation, item-total correlation, internal consistency, and meanings of the items were comprehensively considered in selecting the final 64 items. In order to check on reliability, internal consistency, convergence and discrimination reliability of the final items and scales, the data were collected from 1,046 fourth through sixth graders currently attending four elementary schools. The study results can be summarized as follows. Internal consistency of the inventory of peer relation problems showed the range between .70-.94 (median value of .75), split-half reliability between .67-.83 (median value of .75), and test-retest reliability between .69-.88 (median value of .81). Inter-correlation of 8 scale scores and factor analysis results of individual ipsative scores showed that the circumplex property of inventory of peer relation problems is appropriate. Regarding correlations between various existing indices and scales related to peer relation problems, both convergence reliability and discrimination reliability were found to be fair. When the scale scores for the inventory of peer relation problems compared according to the factors of gender and grade, the primary effects of gender and grade were statistically meaningful whereas effects of interaction between gender and grade were not. This study can be considered meaningful in that it constructed an inventory for a comprehensive evaluation of peer relation problems specific for children and provided preliminary norms.

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