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51.
Peal Michael Hossain Md Shafaeat Chen Jundong 《Journal of Intelligent Information Systems》2022,59(1):193-212
Journal of Intelligent Information Systems - E-commerce giants like Amazon rely on consumer reviews to allow buyers to inform other potential buyers about a product’s pros and cons. While... 相似文献
52.
A new centrality of the nodes in the network is proposed called alternate centrality, which can isolate effective drug targets in the complex signalling network. Alternate centrality metric defined over the network substructure (four nodes – motifs). The nodes involving in alternative activation in the motifs gain in metric values. Targeting high alternative centrality nodes hypothesised to be destructive free to the network due to their alternative activation mechanism. Overlapping and crosstalk among the gene products in the conserved network of MAPK pathways selected for the study. In silico knock‐out of high alternate centrality nodes causing rewiring in the network is investigated using MCF‐7 breast cancer cell line‐based data. Degree of top alternate centrality nodes lies between the degree of bridging and pagerank nodes. Node deletion of high alternate centrality on the centralities such as eccentricity, closeness, betweenness, stress, centroid and radiality causes low perturbation. The authors identified the following alternate centrality nodes ERK1, ERK2, MEKK2, MKK5, MKK4, MLK3, MLK2, MLK1, MEKK4, MEKK1, TAK1, P38alpha, ZAK, DLK, LZK, MLTKa/b and P38beta as efficient drug targets for breast cancer. Alternate centrality identifies effective drug targets and is free from intertwined biological processes and lethality.Inspec keywords: biochemistry, molecular biophysics, cellular biophysics, cancer, drugs, genetics, biomedical materialsOther keywords: MAPK pathways, complex signalling network, pagerank nodes, node deletion, drug targets, MCF‐7 breast cancer cell line‐based data, cellular mechanisms, ERK1 nodes, ERK2 nodes, MEKK2 nodes, MKK5 nodes, MKK4 nodes, MLK3 nodes, MLK2 nodes, MLK1 nodes, MEKK4 nodes, MEKK1 nodes, TAK1 nodes, P38alpha nodes, ZAK nodes, DLK nodes, LZK nodes, MLTKa/b nodes, P38beta nodes 相似文献
53.
Avishek Sarbajna Andres Georg Rösch Leonard Franke Uli Lemmer Md Mofasser Mallick 《Advanced Engineering Materials》2023,25(2):2200980
One of the simplest ways to generate electric power from waste heat is thermoelectric (TE) energy conversion. So far, most of the research on thermoelectrics has focused on inorganic bulk TE materials and their device applications. However, high production costs per power output and limited shape conformity hinder applications of state-of-the-art thermoelectric devices (TEDs). In recent years, printed thermoelectrics has emerged as an exciting pathway for their potential in the production of low-cost shape-conformable TEDs. Although several inorganic bulk TE materials with high performance are successfully developed, achieving high performance in inorganic-based printed TE materials is still a challenge. Nevertheless, significant progress has been made in printed thermoelectrics in recent years. In this review article, it is started with an introduction signifying the importance of printed thermoelectrics followed by a discussion of theoretical concepts of thermoelectricity, from fundamental transport phenomena to device efficiency. Afterward, the general process of inorganic TE ink formulation is summarized, and the current development of the inorganic and hybrid inks with the mention of their TE properties and their influencing factors is elaborated. In the end, TEDs with different architecture and geometries are highlighted by documenting their performance and fabrication techniques. 相似文献
54.
Mostafizur Rahman Rana Erik Upol Biswas Sultan Mahmud Salman Meem Sahel Syeda Sarita Hassan Mahdy Rahman Chowdhury Mahdy 《Advanced Engineering Materials》2023,25(20):2300438
Electromagnetic wideband absorption is still perceived as a critical and formidable challenge to address with an unambiguous photonic absorber. Subwavelength metamaterial (MM) unit cells with unique and controlled features have recently gained considerable interest. However, meta-atoms, generated using a quantum-inspired pattern distribution, are underwhelming in existing literature to design photonic absorbers and their potential application to manufacture solar sails is still quite uncommon. In this article, to create a flexible, polarization-insensitive, ultrathin, and broadband MM absorber, quantum interference pattern-inspired design is utilized. Herein, a novel approach to fabricating solar sails for the space exploration incorporates the proposed broadband photonic absorber rather than conventional reflectors. The quantum-inspired meta-absorber (QIMA) exhibits an absorption of over 91% for the visible domain, i.e., 380–800 nm under a conventional plane-polarized source. It is shown in the study that broadband absorbers are almost equivalent to excellent reflectors to design the solar sails in terms of the time-averaged force calculated by utilizing the Maxwell stress tensor method. Thus, the QIMA has the potential to be a viable alternative to reflectors in the design of futuristic solar sails for space exploration. The interference theory model is also utilized to assure the dependability of calculated data, and additionally, the standard AM1.5 solar spectrum is utilized to demonstrate the QIMA's solar-harvesting potentiality. 相似文献
55.
Accurate location or positioning of people and self-driven devices in large indoor environments has become an important necessity The application of increasingly automated self-operating moving transportation units, in large indoor spaces demands a precise knowledge of their positions. Technologies like WiFi and Bluetooth, despite their low-cost and availability, are sensitive to signal noise and fading effects. For these reasons, a hybrid approach, which uses two different signal sources, has proven to be more resilient and accurate for the positioning determination in indoor environments. Hence, this paper proposes an improved hybrid technique to implement a fingerprinting based indoor positioning, using Received Signal Strength information from available Wireless Local Area Network access points, together with the Wireless Sensor Networks technology. Six signals were recorded on a regular grid of anchor points, covering the research space. An optimization was performed by relative signal weighting, to minimize the average positioning error over the research space. The optimization process was conducted using a standard Quantum Particle Swarm Optimization, while the position error estimate for all given sets of weighted signals was performed using a Multilayer Perceptron (MLP) neural network. Compared to our previous research works, the MLP architecture was improved to three hidden layers and its learning parameters were finely tuned. These experimental results led to the 20% reduction of the positioning error when a suitable set of signal weights was calculated in the optimization process. Our final achieved value of 0.725 m of the location incertitude shows a sensible improvement compared to our previous results. 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.
Md. Salah Uddin Afsar Mohammad Rashed Iqbal Faruque Sabirin Abdullah Mohammad Tariqul Islam 《计算机、材料和连续体(英文)》2023,76(1):455-469
This study proposed a new royal crown-shaped polarisation insensitive double negative triple band microwave range electromagnetic metamaterial absorber (MA). The primary purpose of this study is to utilise the exotic characteristics of this perfect metamaterial absorber (PMA) for microwave wireless communications. The fundamental unit cell of the proposed MA consists of two pentagonal-shaped resonators and two inverse C-shaped metallic components surrounded by a split ring resonator (SRR). The bottom thin copper deposit and upper metallic resonator surface are disjoined by an FR-4 dielectric substrate with 1.6 mm thickness. The CST MW studio, a high-frequency electromagnetic simulator has been deployed for numerical simulation of the unit cell in the frequency range of 4 to 14 GHz. In the TE mode, the offered MA structure demonstrated three different absorption peaks at 6.85 GHz (C-band), 8.87 GHz (X-band), and 12.03 GHz (Ku-band), with 96.82%, 99.24%, and 99.43% absorptivity, respectively. The electric field, magnetic field, and surface current distribution were analysed using Maxwell’s-Curl equations, whereas the angle sensitivity was investigated to comprehend the absorption mechanism of the proposed absorber. The numerical results were verified using the Ansys HFSS (high-frequency structure simulator) and ADS (advanced design system) for equivalent circuit models. Moreover, the proposed MA is polarisation and incident angle independent. Hence, the application of this MA can be extended to a great extent, including airborne radar applications, defence, and stealth-coating technology. 相似文献
58.
Sujan Kumar Roy Md. Khademul Islam Molla Keikichi Hirose Md. Kamrul Hasan 《International Journal of Speech Technology》2011,14(4):339-349
A novel and robust pitch estimation method is presented in this paper. The basic idea is to reshape the speech signal using
a combination of the dominant harmonic modification (DHM) and data adaptive time domain filtering techniques. The noisy speech
signal is filtered within the ranges of fundamental frequencies to obtain the pre-filtered signal (PFS). The dominant harmonic
(DH) of the PFS is determined and enhanced its amplitude. Normalized autocorrelation function (NACF) is applied to that modified
signal. Then empirical mode decomposition (EMD) based data adaptive time domain filtering is applied to the NACF signal. Partial
reconstruction is performed in EMD domain. The pitch period is determined from the partially reconstructed signal. The experimental
results show that the proposed method performs better than the other recently developed methods for noisy and clean speech
signals in terms of gross and fine pitch errors. 相似文献
59.
This paper presents a new algorithm for de-noising global positioning system (GPS) and inertial navigation system (INS) data and estimates the INS error using wavelet multi-resolution analysis algorithm (WMRA)-based genetic algorithm (GA) with a well-designed structure appropriate for practical and real time implementations because of its very short training time and elevated accuracy. Different techniques have been implemented to de-noise and estimate the INS and GPS errors. Wavelet de-noising is one of th... 相似文献
60.
Ananda S. Chowdhury Sovira Tan Jianhua Yao Ronald M. Summers 《Pattern recognition letters》2010,31(9):876-883
Colon cancer is the second major cause of cancer related deaths in industrial nations. Computed tomographic colonography (CTC) has emerged in the last decade as a new less invasive colon diagnostic alternative to the usually practiced optical colonoscopy. The overall goal is to increase the effectiveness of virtual endoscopic navigation of the existing computer-aided detection (CAD) system. The colonic/haustral folds serve as important landmarks for various associated tasks in the virtual endoscopic navigation like prone–supine registration, colonic polyp detection and tenia coli extraction. In this paper, we present two different techniques, first in isolation and then in synergism, for the detection of haustral folds. Our input is volumetric computed tomographic colonography (CTC) images. The first method, which uses a combination of heat diffusion and fuzzy c-means algorithm (FCM), has a tendency of over-segmentation. The second method, which employs level sets, suffers from under-segmentation. A synergistic combination, where the output of the first is used as an input for the second, is shown to improve the segmentation quality. Experimental results are presented on digital colon phantoms as well as real patient scans. The combined method has a total erroneous (over-segmentation plus under-segmentation) detection of (6.5 ± 2)% of the total number of folds per colon as compared to (12.5 ± 5)% for the diffusion-FCM-based method and (11.5 ± 3)% for the level set-based method. The p-values obtained from the associated ANOVA tests indicate that the performance improvements are statistically significant. 相似文献