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991.
Aqib Ali Wali Khan Mashwani Samreen Naeem Muhammad Irfan Uddin Wiyada Kumam Poom Kumam Hussam Alrabaiah Farrukh Jamal Christophe Chesneau 《计算机、材料和连续体(英文)》2021,68(1):391-407
The purpose of this research is the segmentation of lungs computed tomography (CT) scan for the diagnosis of COVID-19 by using machine learning methods. Our dataset contains data from patients who are prone to the epidemic. It contains three types of lungs CT images (Normal, Pneumonia, and COVID-19) collected from two different sources; the first one is the Radiology Department of Nishtar Hospital Multan and Civil Hospital Bahawalpur, Pakistan, and the second one is a publicly free available medical imaging database known as Radiopaedia. For the preprocessing, a novel fuzzy c-mean automated region-growing segmentation approach is deployed to take an automated region of interest (ROIs) and acquire 52 hybrid statistical features for each ROIs. Also, 12 optimized statistical features are selected via the chi-square feature reduction technique. For the classification, five machine learning classifiers named as deep learning J4, multilayer perceptron, support vector machine, random forest, and naive Bayes are deployed to optimize the hybrid statistical features dataset. It is observed that the deep learning J4 has promising results (sensitivity and specificity: 0.987; accuracy: 98.67%) among all the deployed classifiers. As a complementary study, a statistical work is devoted to the use of a new statistical model to fit the main datasets of COVID-19 collected in Pakistan. 相似文献
992.
Youseef Alotaibi Muhammad Noman Malik Huma Hayat Khan Anab Batool Saif ul Islam Abdulmajeed Alsufyani Saleh Alghamdi 《计算机、材料和连续体(英文)》2021,68(3):3323-3338
Social media data are rapidly increasing and constitute a source of user opinions and tips on a wide range of products and services. The increasing availability of such big data on biased reviews and blogs creates challenges for customers and businesses in reviewing all content in their decision-making process. To overcome this challenge, extracting suggestions from opinionated text is a possible solution. In this study, the characteristics of suggestions are analyzed and a suggestion mining extraction process is presented for classifying suggestive sentences from online customers’ reviews. A classification using a word-embedding approach is used via the XGBoost classifier. The two datasets used in this experiment relate to online hotel reviews and Microsoft Windows App Studio discussion reviews. F1, precision, recall, and accuracy scores are calculated. The results demonstrated that the XGBoost classifier outperforms—with an accuracy of more than 80%. Moreover, the results revealed that suggestion keywords and phrases are the predominant features for suggestion extraction. Thus, this study contributes to knowledge and practice by comparing feature extraction classifiers and identifying XGBoost as a better suggestion mining process for identifying online reviews. 相似文献
993.
Javaria Amin Muhammad Sharif Muhammad Almas Anjum Ayesha Siddiqa Seifedine Kadry Yunyoung Nam Mudassar Raza 《计算机、材料和连续体(英文)》2021,69(1):785-799
White blood cells (WBCs) are a vital part of the immune system that protect the body from different types of bacteria and viruses. Abnormal cell growth destroys the body’s immune system, and computerized methods play a vital role in detecting abnormalities at the initial stage. In this research, a deep learning technique is proposed for the detection of leukemia. The proposed methodology consists of three phases. Phase I uses an open neural network exchange (ONNX) and YOLOv2 to localize WBCs. The localized images are passed to Phase II, in which 3D-segmentation is performed using deeplabv3 as a base network of the pre-trained Xception model. The segmented images are used in Phase III, in which features are extracted using the darknet-53 model and optimized using Bhattacharyya separately criteria to classify WBCs. The proposed methodology is validated on three publically available benchmark datasets, namely ALL-IDB1, ALL-IDB2, and LISC, in terms of different metrics, such as precision, accuracy, sensitivity, and dice scores. The results of the proposed method are comparable to those of recent existing methodologies, thus proving its effectiveness. 相似文献
994.
Kamran Sadiq Awan Tahir Mahmood Mohammad Shorfuzzaman Rashid Ali Raja Majid Mehmood 《计算机、材料和连续体(英文)》2021,68(1):29-43
Solar energy is a widely used type of renewable energy. Photovoltaic arrays are used to harvest solar energy. The major goal, in harvesting the maximum possible power, is to operate the system at its maximum power point (MPP). If the irradiation conditions are uniform, the P-V curve of the PV array has only one peak that is called its MPP. But when the irradiation conditions are non-uniform, the P-V curve has multiple peaks. Each peak represents an MPP for a specific irradiation condition. The highest of all the peaks is called Global Maximum Power Point (GMPP). Under uniform irradiation conditions, there is zero or no partial shading. But the changing irradiance causes a shading effect which is called Partial Shading. Many conventional and soft computing techniques have been in use to harvest solar energy. These techniques perform well under uniform and weak shading conditions but fail when shading conditions are strong. In this paper, a new method is proposed which uses Machine Learning based algorithm called Opposition-Based-Learning (OBL) to deal with partial shading conditions. Simulation studies on different cases of partial shading have proven this technique effective in attaining MPP. 相似文献
995.
Sitara Afzal Muazzam Maqsood Irfan Mehmood Muhammad Tabish Niaz Sanghyun Seo 《计算机、材料和连续体(英文)》2021,66(3):2301-2315
Cerebral Microbleeds (CMBs) are microhemorrhages caused by certain abnormalities of brain vessels. CMBs can be found in people with Traumatic Brain Injury (TBI), Alzheimer’s disease, and in old individuals having a brain injury. Current research reveals that CMBs can be highly dangerous for individuals having dementia and stroke. The CMBs seriously impact individuals’ life which makes it crucial to recognize the CMBs in its initial phase to stop deterioration and to assist individuals to have a normal life. The existing work report good results but often ignores false-positive’s perspective for this research area. In this paper, an efficient approach is presented to detect CMBs from the Susceptibility Weighted Images (SWI). The proposed framework consists of four main phases (i) making clusters of brain Magnetic Resonance Imaging (MRI) using k-mean classifier (ii) reduce false positives for better classification results (iii) discriminative feature extraction specific to CMBs (iv) classification using a five layers convolutional neural network (CNN). The proposed method is evaluated on a public dataset available for 20 subjects. The proposed system shows an accuracy of 98.9% and a 1.1% false-positive rate value. The results show the superiority of the proposed work as compared to existing states of the art methods. 相似文献
996.
Syeda Binish Zahra Muhammad Adnan Khan Sagheer Abbas Khalid Masood Khan Mohammed A. Al-Ghamdi Sultan H. Almotiri 《计算机、材料和连续体(英文)》2021,66(2):1269-1282
Biomechanics is the study of physiological properties of data and the measurement of human behavior. In normal conditions, behavioural properties in stable form are created using various inputs of subconscious/conscious human activities such as speech style, body movements in walking patterns, writing style and voice tunes. One cannot perform any change in these inputs that make results reliable and increase the accuracy. The aim of our study is to perform a comparative analysis between the marker-based motion capturing system (MBMCS) and the marker-less motion capturing system (MLMCS) using the lower body joint angles of human gait patterns. In both the MLMCS and MBMCS, we collected trajectories of all the participants and performed joint angle computation to identify a person and recognize an activity (walk and running). Using five state of the art machine learning algorithms, we obtained 44.6% and 64.3% accuracy in person identification using MBMCS and MLMCS respectively with an ensemble algorithm (two angles as features). In the second set of experiments, we used six machine learning algorithms to obtain 65.9% accuracy with the k-nearest neighbor (KNN) algorithm (two angles as features) and 74.6% accuracy with an ensemble algorithm. Also, by increasing features (6 angles), we obtained higher accuracy of 99.3% in MBMCS for person recognition and 98.1% accuracy in MBMCS for activity recognition using the KNN algorithm. MBMCS is computationally expensive and if we re-design the model of OpenPose with more body joint points and employ more features, MLMCS (low-cost system) can be an effective approach for video data analysis in a person identification and activity recognition process. 相似文献
997.
Muhammad Adnan Khan Abdur Rehman Khalid Masood Khan Mohammed A. Al Ghamdi Sultan H. Almotiri 《计算机、材料和连续体(英文)》2021,66(1):467-480
Networks provide a significant function in everyday life, and cybersecurity therefore developed a critical field of study. The Intrusion detection system
(IDS) becoming an essential information protection strategy that tracks the situation of the software and hardware operating on the network. Notwithstanding
advancements of growth, current intrusion detection systems also experience dif-
ficulties in enhancing detection precision, growing false alarm levels and identifying suspicious activities. In order to address above mentioned issues, several
researchers concentrated on designing intrusion detection systems that rely on
machine learning approaches. Machine learning models will accurately identify
the underlying variations among regular information and irregular information
with incredible efficiency. Artificial intelligence, particularly machine learning
methods can be used to develop an intelligent intrusion detection framework.
There in this article in order to achieve this objective, we propose an intrusion
detection system focused on a Deep extreme learning machine (DELM) which
first establishes the assessment of safety features that lead to their prominence
and then constructs an adaptive intrusion detection system focusing on the important features. In the moment, we researched the viability of our suggested DELMbased intrusion detection system by conducting dataset assessments and evaluating the performance factors to validate the system reliability. The experimental
results illustrate that the suggested framework outclasses traditional algorithms.
In fact, the suggested framework is not only of interest to scientific research
but also of functional importance. 相似文献
998.
Naeem Ahmad Jan Saad Hassan Kiani Daniyal Ali Sehrai Muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim 《计算机、材料和连续体(英文)》2021,66(1):35-49
In this paper, a low cost, highly efficient and low profile monopole
antenna for ultra-wideband (UWB) applications is presented. A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high efficiency. To design the proposed structure, three steps
are utilized to achieve an UWB response. The bandwidth of the proposed antenna
is improved with changing meander lines parameters, miniaturization of the
ground width and optimization of the feeding line. The measured and simulated
frequency band ranges from 3.2 to 12 GHz, while the radiation patterns are measured at 4, 5.3, 6 and 8 GHz frequency bands. The overall volume of the proposed
antenna is 26 × 25 × 1.6 mm3
; whereas the FR4 material is used as a substrate
with a relative permittivity and loss tangent of 4.3 and 0.025, correspondingly.
The peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98% for
the entire wideband. Design modelling of proposed antenna is performed in
ANSYS HFSS 13 software. A decent consistency between the simulated and
measured results is accomplished which shows that the proposed antenna is a
potential candidate for the UWB applications. 相似文献
999.
Social networking platforms provide a vital source for disseminating
information across the globe, particularly in case of disaster. These platforms
are great mean to find out the real account of the disaster. Twitter is an example
of such platform, which has been extensively utilized by scientific community due
to its unidirectional model. It is considered a challenging task to identify eyewitness tweets about the incident from the millions of tweets shared by twitter users.
Research community has proposed diverse sets of techniques to identify eyewitness account. A recent state-of-the-art approach has proposed a comprehensive set
of features to identify eyewitness account. However, this approach suffers some
limitation. Firstly, automatically extracting the feature-words remains a perplexing
task against each feature identified by the approach. Secondly, all identified features were not incorporated in the implementation. This paper has utilized the language structure, linguistics, and word relation to achieve automatic extraction of
feature-words by creating grammar rules. Additionally, all identified features were
implemented which were left out by the state-of-the-art model. A generic
approach is taken to cover different types of disaster such as earthquakes, floods,
hurricanes, and wildfires. The proposed approach was then evaluated for all disaster-types, including earthquakes, floods, hurricanes, and fire. Based on the static
dictionary, the Zahra et al. approach was able to produce an F-Score value of
0.92 for Eyewitness identification in the earthquake category. The proposed
approach secured F-Score values of 0.81 in the same category. This score can
be considered as a significant score without using a static dictionary. 相似文献
1000.