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141.
Abbas Mohamed Abbas Sultan Awad Sultan Fernando A. Monteiro Santos 《Bulletin of Engineering Geology and the Environment》2008,67(3):411-414
An area 47 × 26 m adjacent to the Queens’ pyramids near the Menkaure Pyramid, Giza, was examined using 14 parallel Wenner-Schlumberger
profiles at 2 m intervals with a 1 m electrode spacing. Most of the inverted 3-D models show moderate resistivity values at
shallow depths. However, in two places higher resistivity values identified two elongate features. One may correspond to a
2 × 8 m solar boat placed near the pyramid while the other may indicate a 5 × 20 m N–S room with a mud brick roof.
相似文献
142.
This article presents electromagnetic (EM) design of a new folded‐waveguide resonator filter that uses an advanced coupling scheme to achieve the desired asymmetric frequency response with an attenuation pole of finite frequency on the high side of the passband. A filter of this type with a fraction bandwidth about 5% at a center frequency of 4.45 GHz has been successfully designed using a commercially available electromagnetic simulator. The designed filter has been fabricated and tested. Simulations and experimental results are presented to validate the design and to show the advantages of this type of filter. This filter also provides a compact size compared with conventional cavity resonator filters. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
143.
An apparatus made to study the form taken by threads laid on a moving belt under different conditions is described. This mechanism of laying down the thread is a partial imitation of the mechanism of laying down the filaments emerging from the spinnerets during the manufacturing process of spun-bonded non-woven fabrics. It is shown that the form of the laid-down thread can vary according to the type of thread, the height of the feed point, and the ratio of the feed speed to the belt speed. It is also shown that there is a critical value of the speed ratio at which the form changes its geometry considerably. The conditions for a homogeneous and controlled form of the laid thread are deduced. 相似文献
144.
Mazen Mushabab Alqahtani Ashit Kumar Dutta Sultan Almotairi M. Ilayaraja Amani Abdulrahman Albraikan Fahd N. Al-Wesabi Mesfer Al Duhayyim 《计算机、材料和连续体(英文)》2023,74(1):217-233
Recent developments in digital cameras and electronic gadgets coupled with Machine Learning (ML) and Deep Learning (DL)-based automated apple leaf disease detection models are commonly employed as reasonable alternatives to traditional visual inspection models. In this background, the current paper devises an Effective Sailfish Optimizer with EfficientNet-based Apple Leaf disease detection (ESFO-EALD) model. The goal of the proposed ESFO-EALD technique is to identify the occurrence of plant leaf diseases automatically. In this scenario, Median Filtering (MF) approach is utilized to boost the quality of apple plant leaf images. Moreover, SFO with Kapur's entropy-based segmentation technique is also utilized for the identification of the affected plant region from test image. Furthermore, Adam optimizer with EfficientNet-based feature extraction and Spiking Neural Network (SNN)-based classification are employed to detect and classify the apple plant leaf images. A wide range of simulations was conducted to ensure the effective outcomes of ESFO-EALD technique on benchmark dataset. The results reported the supremacy of the proposed ESFO-EALD approach than the existing approaches. 相似文献
145.
Sachin Sharma Meena Malik Chander Prabha Amal Al-Rasheed Mona Alduailij Sultan Almakdi 《计算机、材料和连续体(英文)》2023,75(1):393-407
Watermarking of digital images is required in diversified applications ranging from medical imaging to commercial images used over the web.
Usually, the copyright information is embossed over the image in the form of
a logo at the corner or diagonal text in the background. However, this form
of visible watermarking is not suitable for a large class of applications. In all
such cases, a hidden watermark is embedded inside the original image as proof
of ownership. A large number of techniques and algorithms are proposed
by researchers for invisible watermarking. In this paper, we focus on issues
that are critical for security aspects in the most common domains like digital
photography copyrighting, online image stores, etc. The requirements of this
class of application include robustness (resistance to attack), blindness (direct
extraction without original image), high embedding capacity, high Peak Signal
to Noise Ratio (PSNR), and high Structural Similarity Matrix (SSIM). Most
of these requirements are conflicting, which means that an attempt to maximize one requirement harms the other. In this paper, a blind type of image
watermarking scheme is proposed using Lifting Wavelet Transform (LWT)
as the baseline. Using this technique, custom binary watermarks in the form
of a binary string can be embedded. Hu’s Invariant moments’ coefficients
are used as a key to extract the watermark. A Stochastic variant of the
Firefly algorithm (FA) is used for the optimization of the technique. Under
a prespecified size of embedding data, high PSNR and SSIM are obtained
using the Stochastic Gradient variant of the Firefly technique. The simulation
is done using Matrix Laboratory (MATLAB) tool and it is shown that the
proposed technique outperforms the benchmark techniques of watermarking
considering PSNR and SSIM as quality metrics. 相似文献
146.
Miran Ha Pandiarajan Thangavel Ngoc Kim Dang Dong Yeon Kim Siraj Sultan Jae Sung Lee Kwang S. Kim 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(20):2300240
Electrocatalysts facilitating chlorine evolution reaction (ClER) play a vital role in chlor–alkali industries. Owing to a huge amount of chlorine consumed worldwide, inexpensive high-performing catalysts for Cl2 production are highly demanded. Here, a superb ClER catalyst fabricated through uniform dispersion of Pt single atoms (SAs) in C2N2 moieties of N-doped graphene (denoted as Pt-1) is presented, which demonstrates near 100% exclusive ClER selectivity, long-term durability, extraordinary Cl2 production rate (3500 mmol h−1 gPt−1), and >140 000-fold increased mass activity over industrial electrodes in acidic medium. Excitingly, at the typical chlor–alkali industries’ operating temperature (80 °C), Pt-1 supported on carbon paper electrode requires a near thermoneutral ultralow overpotential of 5 mV at 1 mA cm−2 current density to initiate the ClER, consistent with the predicted density functional theory (DFT) calculations. Altogether these results show the promising electrocatalyst of Pt-1 toward ClER. 相似文献
147.
M. Azeem H.H. Ya M.A. Alam T.H. Sultan M. Ali M. Sattar T. Ahmad H. Hatami M.R. Sadique A.A. Mokhtar M. Mustapha M.A. Khan F. Masood 《Materialwissenschaft und Werkstofftechnik》2021,52(10):1101-1111
Composites are usually brittle materials and have low impact properties. Structural dimensions, stacking sequence, ply materials, ply thicknesses and ply angles are standard variables that influence composite‘s performance against impact loads. Stacking sequence in hybrid laminates affects the failure and impact resistance. Failure mechanisms at the low-velocity impact of a rigid object in hybrid laminates are complex, and the subsurface damage in a composite laminate cannot be detected directly. However, various simulation platforms make it easy to see the impact damage between the plies of laminate. This paper numerically investigated the effect of stack sequence and hybridization of two fiber types against low-velocity impact. The current study adopted four-layer composite laminates of carbon and glass fiber layers with a stacking plan [C/C/C/C], [C/G/C/G] and [G/C/G/C], having lay-up angles as [0°/45°/−45°/90°]. Keeping the impactor mass and the incident velocity constant, the laminates were subjected to low-velocity impact. The damage contours for a failure mode were recorded and compared at the ply level. The numerical study resulted in impact imitations showing comparisons of the damage contours using Hashin failure criteria. Hybrid laminates display better performance in absorbing impact energies; however, hybrid laminates experienced more subsurface damage due to more impact energy absorption. 相似文献
148.
The identification of an effective network which can efficiently meet the service requirements of the target, while maintaining ultimate performance at an increased level is significant and challenging in a fully interconnected wireless medium. The wrong selection can contribute to unwanted situations like frustrated users, slow service, traffic congestion issues, missed and/or interrupted calls, and wastefulness of precious network components. Conventional schemes estimate the handoff need and cause the network screening process by a single metric. The strategies are not effective enough because traffic characteristics, user expectations, network terminology and other essential device metrics are not taken into account. This article describes an intelligent computing technique based on Multiple-Criteria Decision-Making (MCDM) approach developed based on integrated Fuzzy AHP-TOPSIS which ensures flexible usability and maximizes the experience of end-users in miscellaneous wireless settings. In different components the handover need is assessed and the desired network is chosen. Further, fuzzy sets provide effective solutions to address decision making problems where experts counter uncertainty to make a decision. The proposed research endeavor will support designers and developers to identify, select and prioritize best attributes for ensuring flexible usability in miscellaneous wireless settings. The results of this research endeavor depict that this proposed computational procedure would be the most conversant mechanism for determining the usability and experience of end-users. 相似文献
149.
Ali Badawi Emad M. Ahmed Nasser Y. Mostafa F. Abdel-Wahab Sultan E. Alomairy 《Journal of Materials Science: Materials in Electronics》2017,28(15):10877-10884
In this work, the optical and mechanical properties of Fe2O3 nanoparticles (NPs)/chitosan nanocomposite films have been investigated. Nanocomposite films of different weight ratios of Fe2O3 NPs/chitosan (0, 1, 5, 10, 20 and 30 wt%) were fabricated using casting technique. The optical properties of colloidal Fe2O3 NPs and Fe2O3 NPs/chitosan nanocomposite films were recorded using UV–visible spectrophotometer. As the ratio of Fe2O3 NPs to chitosan increases from 0 to 30%, the energy band gap of Fe2O3 NPs/chitosan films decreases from 3.16 to 2.11 eV. This decrease is due to quantum confinement effect. The mechanical properties of the nanocomposite films as a function of sweeping temperature were measured using a dynamic mechanical analyzer. An enhancement in storage modulus, stiffness and glass transition temperature (Tg) has been observed as the ratio of Fe2O3 NPs/chitosan increases. Tg of Fe2O3 NPs/chitosan nanocomposite film shifts towards higher temperature side with respect to pure chitosan film from 152.1 to 166.3?°C as the ratio of Fe2O3 NPs/chitosan increases from 0 to 30 wt%. The increase in Tg is mainly attributed to the decrease in free volumes and vacancies in the nanocomposite films as the weight ratio of Fe2O3 NPs/chitosan increases. 相似文献
150.
Generalized fuzzy bi-ideals of semigroups 总被引:1,自引:0,他引:1
Osman Kazancı Sultan Yamak 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(11):1119-1124
After the introduction of fuzzy sets by Zadeh, there have been a number of generalizations of this fundamental concept. The
notion of (∈, ∈ ∨q)-fuzzy subgroups introduced by Bhakat is one among them. In this paper, using the relations between fuzzy points and fuzzy
sets, the concept of a fuzzy bi-ideal with thresholds is introduced and some interesting properties are investigated. The
acceptable nontrivial concepts obtained in this manner are the (∈, ∈ ∨q)-fuzzy bi-ideals and -fuzzy bi-ideals, which are extension of the concept of a fuzzy bi-ideal in semigroup. 相似文献