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排序方式: 共有2594条查询结果,搜索用时 31 毫秒
51.
High Conductivity in Molecularly p‐Doped Diketopyrrolopyrrole‐Based Polymer: The Impact of a High Dopant Strength and Good Structural Order 下载免费PDF全文
Yevhen Karpov Tim Erdmann Ivan Raguzin Mahmoud Al‐Hussein Marcus Binner Uwe Lappan Manfred Stamm Kirill L. Gerasimov Tetyana Beryozkina Vasiliy Bakulev Denis V. Anokhin Dimitri A. Ivanov Florian Günther Sibylle Gemming Gotthard Seifert Brigitte Voit Riccardo Di Pietro Anton Kiriy 《Advanced materials (Deerfield Beach, Fla.)》2016,28(28):6003-6010
52.
Effect of Initial Annealing Temperature on Microstructural Development and Microhardness in High‐Purity Copper Processed by High‐Pressure Torsion 下载免费PDF全文
Saleh N. Alhajeri Abdulla I. Almazrouee Khaled J. Al‐Fadhalah Terence G. Langdon 《Advanced Engineering Materials》2018,20(1)
The effect of the initial annealing temperature on the evolution of microstructure and microhardness in high purity OFHC Cu is investigated after processing by HPT. Disks of Cu are annealed for 1 h at two different annealing temperatures, 400 and 800 °C, and then processed by HPT at room temperature under a pressure of 6.0 GPa for 1/4, 1/2, 1, 5, and 10 turns. Samples are stored for 6 months after HPT processing to examine the self‐annealing effects. Electron backscattered diffraction (EBSD) measurements are recorded for each disk at three positions: center, mid‐radius, and near edge. Microhardness measurements are also recorded along the diameters of each disk. Both alloys show rapid hardening and then strain softening in the very early stages of straining due to self‐annealing with a clear delay in the onset of softening in the alloy initially annealed at 800 °C. This delay is due to the relatively larger initial grain size compared to the alloy initially annealed at 400 °C. The final microstructures consist of homogeneous fine grains having average sizes of ≈0.28 and ≈0.34 µm for the alloys initially annealed at 400 and 800 °C, respectively. A new model is proposed to describe the behavior of the hardness evolution by HPT in high purity OFHC Cu. 相似文献
53.
High Efficiency Poly(acrylonitrile) Electrospun Nanofiber Membranes for Airborne Nanomaterials Filtration 下载免费PDF全文
Riyadh Al‐Attabi Ludovic F. Dumée Lingxue Kong Jürg A. Schütz Yosry Morsi 《Advanced Engineering Materials》2018,20(1)
54.
Hammam Al‐Bustami Guy Koplovitz Darinka Primc Shira Yochelis Eyal Capua Danny Porath Ron Naaman Yossi Paltiel 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(30)
There is an increasing demand for the development of a simple Si‐based universal memory device at the nanoscale that operates at high frequencies. Spin‐electronics (spintronics) can, in principle, increase the efficiency of devices and allow them to operate at high frequencies. A primary challenge for reducing the dimensions of spintronic devices is the requirement for high spin currents. To overcome this problem, a new approach is presented that uses helical chiral molecules exhibiting spin‐selective electron transport, which is called the chiral‐induced spin selectivity (CISS) effect. Using the CISS effect, the active memory device is miniaturized for the first time from the micrometer scale to 30 nm in size, and this device presents memristor‐like nonlinear logic operation at low voltages under ambient conditions and room temperature. A single nanoparticle, along with Au contacts and chiral molecules, is sufficient to function as a memory device. A single ferromagnetic nanoplatelet is used as a fixed hard magnet combined with Au contacts in which the gold contacts act as soft magnets due to the adsorbed chiral molecules. 相似文献
55.
Khalid A. Alissa Mohammed Maray Areej A. Malibari Sana Alazwari Hamed Alqahtani Mohamed K. Nour Marwa Obbaya Mohamed A. Shamseldin Mesfer Al Duhayyim 《计算机、材料和连续体(英文)》2023,74(3):5349-5367
Emerging technologies such as edge computing, Internet of Things (IoT), 5G networks, big data, Artificial Intelligence (AI), and Unmanned Aerial Vehicles (UAVs) empower, Industry 4.0, with a progressive production methodology that shows attention to the interaction between machine and human beings. In the literature, various authors have focused on resolving security problems in UAV communication to provide safety for vital applications. The current research article presents a Circle Search Optimization with Deep Learning Enabled Secure UAV Classification (CSODL-SUAVC) model for Industry 4.0 environment. The suggested CSODL-SUAVC methodology is aimed at accomplishing two core objectives such as secure communication via image steganography and image classification. Primarily, the proposed CSODL-SUAVC method involves the following methods such as Multi-Level Discrete Wavelet Transformation (ML-DWT), CSO-related Optimal Pixel Selection (CSO-OPS), and signcryption-based encryption. The proposed model deploys the CSO-OPS technique to select the optimal pixel points in cover images. The secret images, encrypted by signcryption technique, are embedded into cover images. Besides, the image classification process includes three components namely, Super-Resolution using Convolution Neural Network (SRCNN), Adam optimizer, and softmax classifier. The integration of the CSO-OPS algorithm and Adam optimizer helps in achieving the maximum performance upon UAV communication. The proposed CSODL-SUAVC model was experimentally validated using benchmark datasets and the outcomes were evaluated under distinct aspects. The simulation outcomes established the supreme better performance of the CSODL-SUAVC model over recent approaches. 相似文献
56.
Muhammad Aadil Siddiqui M. H. Md Khir Zaka Ullah Muath Al Hasan Abdul Saboor Saeed Ahmed Magsi 《计算机、材料和连续体(英文)》2023,75(2):2859-2871
One of the most pressing concerns for the consumer market is the detection of adulteration in meat products due to their preciousness. The rapid and accurate identification mechanism for lard adulteration in meat products is highly necessary, for developing a mechanism trusted by consumers and that can be used to make a definitive diagnosis. Fourier Transform Infrared Spectroscopy (FTIR) is used in this work to identify lard adulteration in cow, lamb, and chicken samples. A simplified extraction method was implied to obtain the lipids from pure and adulterated meat. Adulterated samples were obtained by mixing lard with chicken, lamb, and beef with different concentrations (10%–50% v/v). Principal component analysis (PCA) and partial least square (PLS) were used to develop a calibration model at 800–3500 cm−1. Three-dimension PCA was successfully used by dividing the spectrum in three regions to classify lard meat adulteration in chicken, lamb, and beef samples. The corresponding FTIR peaks for the lard have been observed at 1159.6, 1743.4, 2853.1, and 2922.5 cm−1, which differentiate chicken, lamb, and beef samples. The wavenumbers offer the highest determination coefficient R2 value of 0.846 and lowest root mean square error of calibration (RMSEC) and root mean square error prediction (RMSEP) with an accuracy of 84.6%. Even the tiniest fat adulteration up to 10% can be reliably discovered using this methodology. 相似文献
57.
Masoud Mohazzab Norbert Mulders Melora Larson Al Nash 《Journal of Low Temperature Physics》1998,113(5-6):1031-1036
In this paper we discuss a pulsed second sound experiment, aimed at determining accurately the critical exponent , and the predicted logarithmic correction to scaling, for the superfluid density along a tricritical path in the
3
He-
4
He phase diagram. We present an accurate estimate for the limits for closest approach to the tricritical point, as set by gravitationally induced sample inhomogeneities and finite size effects, and discuss some of the complications associated with measurements close to the tricritical point. 相似文献
58.
59.
Zaher Al Aghbari Ibrahim Kamel Ahmed Mustafa 《Peer-to-Peer Networking and Applications》2011,4(4):391-409
Recently, many applications have used Peer-to-Peer (P2P) systems to overcome the current problems with client/server systems
such as non-scalability, high bandwidth requirement and single point of failure. In this paper, we propose an efficient scheme
to support efficient range query processing over structured P2P systems, while balancing both the storage load and access
load. The paper proposes a rotating token scheme to balance the storage load by placing joining nodes in appropriate locations
in the identifier space to share loads with already overloaded nodes. Then, to support range queries, we utilize an order-preserving
mapping function to map keys to nodes in order preserving way and without hashing. This may result in an access load imbalance
due to non-uniform distribution of keys in the identifier space. Thus, we propose an adaptive replication scheme to relieve
overloaded nodes by shedding some load on other nodes to balance the access load. We derive a formula for estimating the overhead
of the proposed adaptive replication scheme. In this study, we carry simulation experiments with synthetic data to measure
the performance of the proposed schemes. Our simulation experiments show significant gains in both storage load balancing
and access load balancing. 相似文献
60.
An improved algorithm for disaggregating microwave-derived soil moisture based on red, near-infrared and thermal-infrared data 总被引:3,自引:0,他引:3
Accurate high-resolution soil moisture data are needed for a range of agricultural and hydrologic activities. To improve the spatial resolution of ∼ 40 km resolution passive microwave-derived soil moisture, a methodology based on 1 km resolution MODIS (MODerate resolution Imaging Spectroradiometer) red, near-infrared and thermal-infrared data has been implemented at 4 km resolution. The three components of that method are (i) fractional vegetation cover, (ii) soil evaporative efficiency (defined as the ratio of actual to potential evaporation) and (iii) a downscaling relationship. In this paper, 36 different disaggregation algorithms are built from 3 fractional vegetation cover formulations, 3 soil evaporative efficiency models, and 4 downscaling relationships. All algorithms differ with regard to the representation of the nonlinear relationship between microwave-derived soil moisture and optical-derived soil evaporative efficiency. Airborne L-band data collected over an Australian agricultural area are used to both generate ∼ 40 km resolution microwave pixels and verify disaggregation results at 4 km resolution. Among the 36 disaggregation algorithms, one is identified as being more robust (insensitive to soil, vegetation and atmospheric variables) than the others with a mean slope between MODIS-disaggregated and L-band derived soil moisture of 0.94. The robustness of that algorithm is notably assessed by comparing the disaggregation results obtained using composited (averaged) Terra and Aqua MODIS data, and using data from Terra and Aqua separately. The error on disaggregated soil moisture is systematically reduced by compositing daily Terra and Aqua data with an error of 0.012 vol./vol. 相似文献