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971.
Skin segmentation participates significantly in various biomedical applications, such as skin cancer identification and skin lesion detection. This paper presents a novel framework for segmenting the skin. The framework contains two main stages: The first stage is for removing different types of noises from the dermoscopic images, such as hair, speckle, and impulse noise, and the second stage is for segmentation of the dermoscopic images using an attention residual U-shaped Network (U-Net). The framework uses variational Autoencoders (VAEs) for removing the hair noises, the Generative Adversarial Denoising Network (DGAN-Net), the Denoising U-shaped U-Net (D-U-NET), and Batch Renormalization U-Net (Br-U-NET) for removing the speckle noise, and the Laplacian Vector Median Filter (MLVMF) for removing the impulse noise. In the second main stage, the residual attention u-net was used for segmentation. The framework achieves (35.11, 31.26, 27.01, and 26.16), (36.34, 33.23, 31.32, and 28.65), and (36.33, 32.21, 28.54, and 27.11) for removing hair, speckle, and impulse noise, respectively, based on Peak Signal Noise Ratio (PSNR) at the level of (0.1, 0.25, 0.5, and 0.75) of noise. The framework also achieves an accuracy of nearly 94.26 in the dice score in the process of segmentation before removing noise and 95.22 after removing different types of noise. The experiments have shown the efficiency of the used model in removing noise according to the structural similarity index measure (SSIM) and PSNR and in the segmentation process as well. 相似文献
972.
973.
Mohamed Nasr Saleh Ying Wang Arief Yudhanto Adam Joesbury Prasad Potluri Gilles Lubineau Constantinos Soutis 《Applied Composite Materials》2017,24(2):377-396
The effect of circular notch has been evaluated for three different architectures of three-dimensional (3D) carbon fibre woven composites (orthogonal, ORT; layer-to-layer, LTL; angle interlock, AI) through open-hole quasi-static tension and double-lap bearing strength tests in the off-axis (45°) direction. Damage characterisation is monitored using Digital Image correlation (DIC) for open-hole testing and X-ray Computed Tomography (CT) for double-lap bearing strength test. The off-axis notched 3D woven composites exhibits minor reduction (less than 10 %) of the notched strength compared to the un-notched strength. DIC strain contour clearly show stress/strain localisation regions around the hole periphery and stress/strain redistribution away from the whole due to the z-binder existence, especially for ORT architecture. Up to 50 % bearing strain, no significant difference in the bearing stress/bearing strain response is observed. However when ORT architecture was loaded up to failure, it demonstrates higher strain to failure (~140 %) followed by AI (~105 %) and lastly LTL (~85 %). X-ray CT scans reveal the effect of the z-binder architecture on damage evolution and delamination resistance. The study suggests that off-axis loaded 3D woven composites, especially ORT architecture, has a great potential of overcoming the current challenges facing composite laminates when used in composite joints’ applications. 相似文献
974.
Asadullah Shaikh Mana Saleh AlReshan Yousef Asiri Adel Sulaiman Hani Alshahrani 《计算机、材料和连续体(英文)》2021,67(1):549-576
In Wuhan, China, a novel Corona Virus (COVID-19) was detected in December 2019; it has changed the entire world and to date, the number of diagnosed cases is 38,756,2891 and 1,095,2161 people have died. This happened because a large number of people got affected and there is a lack of hospitals for COVID-19 patients. One of the precautionary measures for COVID-19 patients is isolation. To support this, there is an urgent need for a platform that makes treatment possible from a distance. Telemedicine systems have been drastically increasing in number and size over recent years. This increasing number intensifies the extensive need for telemedicine for the national healthcare system. In this paper, we present Tele-COVID which is a telemedicine application to treat COVID-19 patients from a distance. Tele-COVID is uniquely designed and implemented in Service-Oriented Architecture (SOA) to avoid the problem of interoperability, vendor lock-in, and data interchange. With the help of Tele-COVID, the treatment of patients at a distance is possible without the need for them to visit hospitals; in case of emergency, necessary services can also be provided. 相似文献
975.
Preparation of a MWCNT/ZnO nanocomposite and its photocatalytic activity for the removal of cyanide from water using a laser 总被引:1,自引:0,他引:1
Nano-zinc oxide (n-ZnO) was loaded onto multi-walled carbon nanotubes (MWCNTs) via a hydrothermal process. Here pure n-ZnO used for loading was synthesized by the pulsed-laser ablation technique while MWCNTs were used as received. The synthesized MWCNT/ZnO nanocomposites were characterized using x-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy and Fourier transform infrared spectrometry. A model has been proposed for the structural nature of the alignment of ZnO on the surface of MWCNTs. The photocatalytic activity in the removal of highly toxic substances like cyanide (CN) was carried out in a special reactor using pulsed 355 nm UV generated by the third harmonic of an Nd:YAG laser. In order to understand the cyanide removal process, the study was carried out at different laser irradiation times, incident laser energies, pH of the solution and dosage of the MWCNT/ZnO nanocomposite. The study demonstrated that the CN removal process by MWCNT/ZnO composite has higher photocatalytic activity than pure n-ZnO and MWCNTs alone. The mechanism for the degradation using MWCNT/ZnO has been schematically explained. It was noticed that the oxidation process activity is affected by the pH of the solution, and after 20 min of UV laser irradiation, approximately 90% of CN had been degraded. 相似文献
976.
Ala Saleh Alluhaidan Masoud Alajmi Fahd N. Al-Wesabi Anwer Mustafa Hilal Manar Ahmed Hamza Abdelwahed Motwakel 《计算机、材料和连续体(英文)》2022,72(2):2713-2730
Human fall detection (FD) acts as an important part in creating sensor based alarm system, enabling physical therapists to minimize the effect of fall events and save human lives. Generally, elderly people suffer from several diseases, and fall action is a common situation which can occur at any time. In this view, this paper presents an Improved Archimedes Optimization Algorithm with Deep Learning Empowered Fall Detection (IAOA-DLFD) model to identify the fall/non-fall events. The proposed IAOA-DLFD technique comprises different levels of pre-processing to improve the input image quality. Besides, the IAOA with Capsule Network based feature extractor is derived to produce an optimal set of feature vectors. In addition, the IAOA uses to significantly boost the overall FD performance by optimal choice of CapsNet hyperparameters. Lastly, radial basis function (RBF) network is applied for determining the proper class labels of the test images. To showcase the enhanced performance of the IAOA-DLFD technique, a wide range of experiments are executed and the outcomes stated the enhanced detection outcome of the IAOA-DLFD approach over the recent methods with the accuracy of 0.997. 相似文献
977.
978.
TA Abanina 《Canadian Metallurgical Quarterly》1982,18(11):1884-1893
This report is a third one in a series of works devoted to the genetic structure (biodemographic studies) of the Forest Nentsy. The main parameters of the population studied were as follows: the total number in seven subpopulations amounting to 1734 persons, the sex ratio 0.93, percentage of children in the group of 0 to 15 years old--39,1%, reproductive and effective sizes--29,5% and 22,0%, respectively, the mean number and variance of offspring per mating, when reproduction is completed being 2,7 (5,2). It has been shown that kin and territorial subdivision of the population contributes to the formation of conjugal pairs and migration pattern. Within-kin matings make 0,041, whereas, according to the panmixia hypothesis, this value would be 0,243. The average index of isolation for particular subpopulation is 62,7%. An exchange of migrants occurs between adjacent groups. Migration stream to the different subpopulations varies in volume and ethnic composition. Analysis of the admixture based on the pedigree isoname method has shown that the proportion of the Forest Nentsy gene contribution to their own population is 74,4%. Data on subpopulation size, patterns of matings, migration and admixture may serve as a basis to account for intrapopulation heterogeneity. 相似文献
979.
N.K. Za'aba ;M.A. Mohd Sarjidan ;W.H. Abd. Majid ;Eny Kusrini ;Muhammad I. Saleh 《中国稀土学报(英文版)》2014,32(7):633-640
Terbium-picrate triethylene glycol(EO3-Tb-Pic) complex was prepared in thin film and single layer device structure of ITO/EO3-Tb-Pic/Al, using spin coating technique. The UV-Vis absorption spectroscopy analysis was performed to evaluate the electronic molecular transition of the complex. The optical band gap, Eg estimated from the Tauc model revealed that EO3-Tb-Pic thin film exhibited a direct transition with Eg of 2.70 eV. The electronic parameters of the ITO/EO3-Tb-Pic/Al device such as the ideality factor n, barrier height Φb, saturation current Io, and series resistance Rs, were extracted from the conventional lnI-V, Cheung's functions and Norde's method. It was found that the evaluated parameters calculated from Norde's and Cheung's methods were consistent with those calculated from the conventional I-V method. In the double logarithmic I-V plot, three distinct regions based on the slope were identified, and the conduction mechanisms were discussed and explained. The mobility, μ value was estimated from SCLC region as 2.58×10^–7 cm2/(V·s). This newly obtained lanthanide complex may be potentially utilized in electronic devices. 相似文献
980.
JS Isaacs R Hardman TA Carman JC Barrett BE Weissman 《Canadian Metallurgical Quarterly》1998,9(7):545-555
Neuroblastoma (NB) cells in vitro are capable of bidirectional transdifferentiation, resulting in two distinct, yet reversible, phenotypes of neuroblastic (N-type) and nonneuronal (S-type) Schwann-like cells. Our previous studies suggested that the wild-type p53 protein is subject to differential regulation in a subset of neuronal cell types. To further test this hypothesis, we compared p53 function in three matched pairs of N- and S-type cell lines, each pair originating from an individual NB tumor. Our data show that although p53 remains cytoplasmically sequestered in a punctate pattern in N-type cells after DNA damage, the protein is diffusely distributed in the S-type cells and is additionally capable of translocating to the nucleus and mediating a biological response to this damage. Our data, therefore, suggest that the p53 protein may be differentially regulated by a neuronal cellular environment and that the sequestration of p53 in NB may be reversible. 相似文献