Diagnosis of Cell Internal Defects with Multi-cycle Test Patterns

Author(s):  
Xiaoxin Fan ◽  
Manish Sharma ◽  
Wu-Tung Cheng ◽  
Sudhakar M. Reddy
Keyword(s):  

2015 ◽  
Vol 7 (2) ◽  
pp. 1428-1439
Author(s):  
Khurshed Alam ◽  
Md. Sayeedur Rahman ◽  
Md. Mostafizur Rahman ◽  
S. M. Azaharul Islam

A powerful non-destructive testing (NDT) technique is adopted to study the internal defects and elemental distribution/homogeneity and porosity of aerated brick and EPS aggregate poly brick samples. In the present study the internal defects like homogeneity, porosity, elemental distribution, EPS aggregate and aerator distributor in the test samples have been observed by the measurement of gray value/optical density of the neutron radiographic images of these samples. From this measurement it is found that the neutron intensity/optical density variation with the pixel distance of the AOI of the NR images in both expanded polystyrene (EPS) aggregate poly brick and aerated brick samples comply almost same in nature with respect to the whole AOI but individually each AOI shows different nature from one AOI to another and it confirms that the elemental distribution within a AOI is almost homogeneous. Finally it was concluded that homogeneity, elemental distribution in the EPS aggregate poly brick sample is better than that of the aerated brick sample. 





2021 ◽  
Vol 282 ◽  
pp. 122642 ◽  
Author(s):  
Jing Xie ◽  
Changwei Wu ◽  
Lemei Gao ◽  
Changhang Xu ◽  
Yinsheng Xu ◽  
...  


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Soo Hyun Park ◽  
Sang Ha Noh ◽  
Michael J. McCarthy ◽  
Seong Min Kim

AbstractThis study was carried out to develop a prediction model for soluble solid content (SSC) of intact chestnut and to detect internal defects using nuclear magnetic resonance (NMR) relaxometry and magnetic resonance imaging (MRI). Inversion recovery and Carr–Purcell–Meiboom–Gill (CPMG) pulse sequences used to determine the longitudinal (T1) and transverse (T2) relaxation times, respectively. Partial least squares regression (PLSR) was adopted to predict SSCs of chestnuts with NMR data and histograms from MR images. The coefficient of determination (R2), root mean square error of prediction (RMSEP), ratio of prediction to deviation (RPD), and the ratio of error range (RER) of the optimized model to predict SSC were 0.77, 1.41 °Brix, 1.86, and 11.31 with a validation set. Furthermore, an image-processing algorithm has been developed to detect internal defects such as decay, mold, and cavity using MR images. The classification applied with the developed image processing algorithm was over 94% accurate to classify. Based on the results obtained, it was determined that the NMR signal could be applied for grading several levels by SSC, and MRI could be used to evaluate the internal qualities of chestnuts.



2020 ◽  
pp. 1-1
Author(s):  
Amal Gunatilake ◽  
Lasitha Piyathilaka ◽  
Antony Tran ◽  
Vinoth Kumar Viswanathan ◽  
Karthick Thiyagarajan ◽  
...  


Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 329
Author(s):  
Pengmin Yan ◽  
Xue Zhao ◽  
Jiuhou Rui ◽  
Juan Zhao ◽  
Min Xu ◽  
...  

The internal defect is an important factor that could influence the energy and safety properties of energetic materials. RDX samples of two qualities were characterized and simulated to reveal the influence of different defects on sensitivity. The internal defects were characterized with optical microscopy, Raman spectroscopy and microfocus X-ray computed tomography technology. The results show that high-density RDX has fewer defects and a more uniform distribution. Based on the characterization results, defect models with different defect rates and distribution were established. The simulation results show that the models with fewer internal defects lead to shorter N-NO2 maximum bond lengths and greater cohesive energy density (CED). The maximum bond length and CED can be used as the criterion for the relative sensitivity of RDX, and therefore defect models doped with different solvents are established. The results show that the models doped with propylene carbonate and acetone lead to higher sensitivity. This may help to select the solvent to prepare low-sensitivity RDX. The results reported in this paper are aiming at the development of a more convenient and low-cost method for studying the influence of internal defects on the sensitivity of energetic materials.





2015 ◽  
Author(s):  
Mingjian Sun ◽  
Ying Fu ◽  
Ting Liu ◽  
Xingzhen Cheng ◽  
Guanji Leng ◽  
...  


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