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排序方式: 共有1017条查询结果,搜索用时 156 毫秒
151.
Fraser Daniel Naim Hossain Patoary Arden L. Moore Leland Weiss Adarsh D. Radadia 《The International Journal of Advanced Manufacturing Technology》2018,99(5-8):1215-1224
This study characterizes the microstructure and temperature dependence of resistance of two commercially available electrically conductive polylactic acid (PLA) composites for fused deposition modeling (FDM): PLA-carbon black and PLA-graphene. No microstructural changes were observed between the filament and the printed parts; however, the resistivity of the filament was found to drop by four to six times upon FDM. Also, compared to the resistivity of individual extruded wire, the resistivity of the printed parts was found to be up to 1500 times higher for PLA-graphene and up to 300 times higher for PLA-carbon black. The raw PLA-carbon black filament and printed wire showed a positive temperature coefficient of resistance (α) value between ~?0.03 and 0.01 °C?1, which makes them more suitable for sensor development. The raw PLA-graphene filament and printed wire did not exhibit a significant α, which makes them more suitable for printing wires. However, the parts made with multilayer FDM exhibited a negative or a negligible α up to a certain temperature prior to exhibiting a positive α; further, these α values were significantly lower than those obtained for the filaments before or after extrusion. These findings enable proper selection of commercial conductive FDM filaments for enabling quicker prototyping of electronics and sensors. 相似文献
152.
Wireless Networks - In this paper, we consider full-duplex (FD) two-way relaying networks, where wireless power transfers from hybrid power access-point, H to user and wireless information... 相似文献
153.
Wearable Devices: Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring (Adv. Mater. 39/2017)
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154.
Lewis Nkenyereye S. M. Riazul Islam Mahmud Hossain M. Abdullah-Al-Wadud Atif Alamri 《计算机、材料和连续体(英文)》2021,67(1):211-221
The Internet of Medical Things (IoMT) offers an infrastructure made of smart medical equipment and software applications for healthcare services. Through the internet, the IoMT is capable of providing remote medical diagnosis and timely health services. The patients can use their smart devices to create, store and share their electronic health records (EHR) with a variety of medical personnel including medical doctors and nurses. However, unless the underlying commination within IoMT is secured, malicious users can intercept, modify and even delete the sensitive EHR data of patients. Patients also lose full control of their EHR since most healthcare services within IoMT are constructed under a centralized platform outsourced in the cloud. Therefore, it is appealing to design a decentralized, auditable and secure EHR system that guarantees absolute access control for the patients while ensuring privacy and security. Using the features of blockchain including decentralization, auditability and immutability, we propose a secure EHR framework which is mainly maintained by the medical centers. In this framework, the patients’ EHR data are encrypted and stored in the servers of medical institutions while the corresponding hash values are kept on the blockchain. We make use of security primitives to offer authentication, integrity and confidentiality of EHR data while access control and immutability is guaranteed by the blockchain technology. The security analysis and performance evaluation of the proposed framework confirms its efficiency. 相似文献
155.
Chakraborty Malay Dey Tina Bera Kamal Kanti Roy Partha Sarathi Ghorai Kalyan Hossain Akbar Bhattacharya Swapan Kumar 《Journal of Materials Science》2022,57(3):2021-2038
Journal of Materials Science - Palladium–bismuth oxoiodide nanocomposites of various molar ratios of Pd and BiOI have been synthesized by the facile solvothermal method following the chemical... 相似文献
156.
Nur A. A. Rahman Mohd A. Jamlos Mohd F. Jamlos Ping J. Soh Norfatihah Bahari Toufiq M. Hossain 《国际射频与微波计算机辅助工程杂志》2020,30(5)
This article presents a newly circularly polarized (CP) antenna for V2X's dedicated short range communications applications. Its CP characteristic is enabled by a 70 Ω sequential phase feeding network and sequential rotation technique designed on top of the substrate. It has features of ≈90° phase difference in sequence between ports of S21 = 2.4°, S31 = ?87°, S41 = ?180°, and S51 = ?276°, resulting in a 2.19 dB axial ratio centered at 5.9 GHz. The length of the SP feeding network to each ports designed in the different form of meander lines are the key to control the generated phase at the center frequency It also contributes to the smaller final size of 0.59λ × 0.59λ. The proposed antenna operated from 5.850 to 5.925 GHz with a gain between 4 and 6 dBi. The gains are radiated in bidirectional mode due to the presence of the complimentary dipoles located on the opposite side of the substrate. These features indicate the suitability of the proposed antenna in compliance to the ITS‐G5 OBU V2X standard. 相似文献
157.
Wireless Personal Communications - Wireless sensor networks (WSNs) are one of the very active research area. They have many applications like military, health care, environmental monitoring and... 相似文献
158.
Al-Qurishi Muhammad Alhuzami Saad AlRubaian Majed Hossain M. Shamim Alamri Atif Rahman Md. Abdur 《Multimedia Tools and Applications》2018,77(9):11179-11201
Multimedia Tools and Applications - Online Social Networks (OSNs) have recently been the subject of numerous studies that have attempted to develop effective methods for classifying and analyzing... 相似文献
159.
Vishal Singh Hossain Chizari Farzad Ismail Appendix by Rémi Abgrall 《Journal of scientific computing》2018,76(3):1521-1546
This paper solves the advection–diffusion equation by treating both advection and diffusion residuals in a separate (non-unified) manner. An alternative residual distribution (RD) method combined with the Galerkin method is proposed to solve the advection–diffusion problem. This Flux-Difference RD method maintains a compact-stencil and the whole process of solving advection–diffusion does not require additional equations to be solved. A general mathematical analysis reveals that the new RD method is linearity preserving on arbitrary grids for the steady-state advection–diffusion equation. The numerical results show that the flux difference RD method preserves second-order accuracy on various unstructured grids including highly randomized anisotropic grids on both the linear and nonlinear scalar advection–diffusion cases. 相似文献
160.
Bei Zhao Dingyi Shen Zucheng Zhang Ping Lu Mongur Hossain Jia Li Bo Li Xidong Duan 《Advanced functional materials》2021,31(48):2105132
2D materials and the associated heterostructures define an ideal material platform for investigating physical and chemical properties, and exhibiting new functional applications in (opto)electronic devices, electrocatalysis, and energy storage. 2D transition metal dichalcogenides (2D TMDs), as a member of the 2D materials family including 2D semiconducting TMDs (s-TMDs) and 2D metallic/semimetallic TMDs (m-TMDs) have attracted considerable attention in the scientific community. Over the past decade, the 2D s-TMDs have been extensively researched and reviewed elsewhere. Because of their distinctive physical properties including intrinsic magnetism, charge-density-wave order and superconductivity, and potential applications, such as high-performance electronic devices, catalysis, and as metal electrode contacts, 2D m-TMDs have grabbed widespread attention in recent years. However, reviews demonstrating the m-TMDs systematically and comprehensively have been rarely reported. Here, the recent advances in 2D m-TMDs in the aspects of their unique structures, synthetic approaches, distinctive physical properties, and functional applications are highlighted. Finally, the current challenges and perspectives are discussed. 相似文献