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Synthesis, Characterization and X-ray Structure of N-(4-bromobutanoyl-N'-(2-3-and 4-methylphenyl)thiourea

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Chinese Journal of Structural Chemistry 2015年第3期34卷 379-385页

作者： hamza M Abosadiya Siti Aishah Hasbullah Bohari M Yamin School of Chemical Sciences and Food Technology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia

N-4-（bromobutanoyl）-N＇-（o-, m- and p-tolyl）thioureas 3a, 3b and 3c respectively, were synthesized by the reaction of 4-bromobutanoylisothiocyanate with p-, m- and o-toludine. The products were characterized by IR, and NMR spectroscopic techniques. The two carbonoylthiourea isomers N-（4-bromobutanoyl）-N＇-（3-methylphenyl）thiourea （3b） and N-（4-bromobutanoyl）-N＇-（4- methylphenyl）thiourea （3c） were obtained in crystalline form by recrystallization from DMSO. X- ray crystallographic studies showed that both compounds 3b and 3c crystallize in triclinic system with space group ofPi. The molecules adopt trans-cis configuration with respect to the positions of 4-bromobutanoyl and tolyl groups respectively, against the thiono C=S bond across their C-N bonds The configuration is attributed by the intrahydrogen bond between the carbonyl oxygen and amide hydrogen atoms. Both crystal structures are stabilized by N-H…S intermolecular hydrogen bonds to form dimers and arranged along the b axis.

关键词： 4-bromobutyryl chloride, thiourea derivatives, X-ray structural study

Embedding Extraction for Arabic Text Using the AraBERT Model

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Computers, Materials & Continua 2022年第7期72卷 1967-1994页

作者： Amira Hamed Abo-Elghit Taher hamza Aya Al-Zoghby Faculty of Computers and Information Department of Computer SciencesMansoura UniversityMansoura35516Egypt Faculty of Computers and Artificial Intelligence Department of Computer SciencesDamietta UniversityDamietta34517Egypt

Nowadays,we can use the multi-task learning approach to train a machine-learning algorithm to learn multiple related tasks instead of training it to solve a single *** this work,we propose an algorithm for estimating textual similarity scores and then use these scores in multiple tasks such as text ranking,essay grading,and question answering *** used several vectorization schemes to represent the Arabic texts in the SemEval2017-task3-subtask-D *** used schemes include lexical-based similarity features,frequency-based features,and pre-trained model-based ***,we used contextual-based embedding models such as Arabic Bidirectional Encoder Representations from Transformers(AraBERT).We used the AraBERT model in two different ***,as a feature extractor in addition to the text vectorization schemes’*** fed those features to various regression models to make a prediction value that represents the relevancy score between Arabic text ***,AraBERT is adopted as a pre-trained model,and its parameters are fine-tuned to estimate the relevancy scores between Arabic textual *** evaluate the research results,we conducted several experiments to compare the use of the AraBERT model in its two *** terms of Mean Absolute Percentage Error(MAPE),the results showminor variance between AraBERT v0.2 as a feature extractor(21.7723)and the fine-tuned AraBERT v2(21.8211).On the other hand,AraBERT v0.2-Large as a feature extractor outperforms the finetuned AraBERT v2 model on the used data set in terms of the coefficient of determination(R2)values(0.014050,−0.032861),respectively.

关键词： Semantic textual similarity arabic language embeddings AraBERT pre-trained models regression contextual-based models concurrency concept

Extensive Study of Cloud Computing Technologies, Threats and Solutions Prospective

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Computer Systems Science & Engineering 2022年第4期41卷 225-240页

作者： Mwaffaq Abu-Alhaija Nidal M.Turab AbdelRahman hamza Department of Networks and Information Security Faculty of Information TechnologyAl-Ahliyya Amman UniversityAmman19328Jordan Department of Computer Science Information TechnologyAl-Ahliyya Amman UniversityAmman19328Jordan

Infrastructure as a Service(IaaS)provides logical separation between data,network,applications and machines from the physical constrains of real *** is one of the basis of cloud ***,security issues are also gradually emerging with virtualization of cloud *** security aspects of cloud virtualization will be explored in this research paper,security recognizing potential threats or attacks that exploit these vulnerabilities,and what security measures are used to alleviate such *** addition,a dis-cussion of general security requirements and the existing security schemes is also *** shown in this paper,different components of virtualization environ-ment are targets to various attacks that in turn leads to security issues compromis-ing the whole cloud *** this paper an overview of various cloud security aspects is also *** attack scenarios of virtualization envir-onments and security solutions to cater these attacks have been discussed in the *** then proceed to discuss API security concerns,data security,hijacking of user account and other security *** aforementioned discussions can be used in the future to propose assessment criteria,which could be useful in ana-lyzing the efﬁciency of security solutions of virtualization environment in the face of various virtual environment attacks.

关键词： Cloud computing environment paravirtualization full virtualization cloud virtualization security hypervisor virtual machines

Modified Harris Hawks Optimization Based Test Case Prioritization for Software Testing

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Computers, Materials & Continua 2022年第7期72卷 1951-1965页

作者： Manar Ahmed hamza Abdelzahir Abdelmaboud Souad Larabi-Marie-Sainte Haya Mesfer Alshahrani Mesfer Al Duhayyim hamza Awad Ibrahim Mohammed Rizwanullah Ishfaq Yaseen Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharj16278Saudi Arabia Department of Information Systems College of Science and ArtsKing Khalid UniversityMahayil Asir62529Saudi Arabia Department of Computer Science College of Computer and Information SciencesPrince Sultan UniversityP.O.Box No.66833Rafha StreetRiyadh11586Saudi Arabia Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Natural and Applied Sciences College of Community-AflajPrince Sattam bin Abdulaziz University16278Saudi Arabia College of Computer at Al-Gunfudah Umm Al-Qura UniversityAl-Gunfudah24382Saudi Arabia

Generally,software testing is considered as a proficient technique to achieve improvement in quality and reliability of the ***,the quality of test cases has a considerable influence on fault revealing capability of software testing *** Case Prioritization(TCP)remains a challenging issue since prioritizing test cases is unsatisfactory in terms of Average Percentage of Faults Detected(APFD)and time spent upon execution *** ismainly intended to design a collection of test cases that can accomplish early optimization using preferred *** studies conducted earlier focused on prioritizing the available test cases in accelerating fault detection rate during software *** this aspect,the current study designs aModified Harris Hawks Optimization based TCP(MHHO-TCP)technique for software *** aim of the proposed MHHO-TCP technique is to maximize APFD and minimize the overall execution *** addition,MHHO algorithm is designed to boost the exploration and exploitation abilities of conventional HHO *** order to validate the enhanced efficiency of MHHO-TCP technique,a wide range of simulations was conducted on different benchmark programs and the results were examined under several *** experimental outcomes highlight the improved efficiency of MHHO-TCP technique over recent approaches under different measures.

关键词： Software testing harris hawks optimization test case prioritization apfd execution time metaheuristics

Transfer Learning-Based Semi-Supervised Generative Adversarial Network for Malaria Classification

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Computers, Materials & Continua 2023年第3期74卷 6335-6349页

作者： Ibrar Amin Saima Hassan Samir Brahim Belhaouari Muhammad hamza Azam Institute of Computing Kohat University of Science and TechnologyKohat26000K.P.KPakistan College of Science and Engineering Hamad bin Khalifa UniversityDohaQatar Centre of Research in Data Science Computer and Information Sciences DepartmentUniversiti Teknologi PETRONASSeri Iskandar32610PerakMalaysia

Malaria is a lethal disease responsible for thousands of deaths worldwide every *** methods of malaria diagnosis are timeconsuming that require a great deal of human expertise and *** automated diagnosis of diseases is progressively becoming *** deep learning models show high performance in the medical field,it demands a large volume of data for training which is hard to acquire for medical ***,labeling of medical images can be done with the help of medical experts *** recent studies have utilized deep learning models to develop efficient malaria diagnostic system,which showed promising ***,the most common problem with these models is that they need a large amount of data for *** paper presents a computer-aided malaria diagnosis system that combines a semi-supervised generative adversarial network and transfer *** proposed model is trained in a semi-supervised manner and requires less training data than conventional deep learning *** of the proposed model is evaluated on a publicly available dataset of blood smear images(with malariainfected and normal class)and achieved a classification accuracy of 96.6%.

关键词： Generative adversarial network transfer learning semi-supervised malaria VGG16

Malicious Code Detection Model Based on Behavior Association

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Tsinghua Science and Technology 2014年第5期19卷 508-515页

作者： Lansheng Han Mengxiao Qian Xingbo Xu Cai Fu hamza Kwisaba Lab.of Information Security School of Computer ScienceHuazhong University of Science and Technology

Malicious applications can be introduced to attack users and services so as to gain financial rewards, individuals＇ sensitive information, company and government intellectual property, and to gain remote control of systems. However, traditional methods of malicious code detection, such as signature detection, behavior detection, virtual machine detection, and heuristic detection, have various weaknesses which make them unreliable. This paper presents the existing technologies of malicious code detection and a malicious code detection model is proposed based on behavior association. The behavior points of malicious code are first extracted through API monitoring technology and integrated into the behavior; then a relation between behaviors is established according to data dependence. Next, a behavior association model is built up and a discrimination method is put forth using pushdown automation. Finally, the exact malicious code is taken as a sample to carry out an experiment on the behavior＇s capture, association, and discrimination, thus proving that the theoretical model is viable.

关键词： malicious code behavior monitor behavior association pushdown automation

Hypoxia inducible factor-1 alpha stabilization for regenerative therapy in traumatic brain injury

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Neural Regeneration Research 2017年第5期12卷 696-701页

作者： Mushfiquddin Khan hamza Khan Inderjit Singh Avtar K.Singh Department of Pediatrics Medical University of South Carolina Charleston SC USA College of Medicine University of South Carolina Columbia SC USA Department of Pathology and Laboratory Medicine Medical University of South Carolina Charleston SC USA Ralph H. Johnson VA Medical Center Charleston SC USA

Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.

关键词： traumatic brain injury hypoxia inducible factor-1 alpha S-nitrosoglutathione neurorepair functional recovery

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增材制造高熵合金复合材料综述

Transactions of Nonferrous Metals Society of China 2023年第1期33卷 1-24页

作者： hamza OSMAN 柳林华中科技大学材料科学与工程学院材料成型与模具技术国家重点实验室武汉430074 Department of Mining and Petroleum Faculty of EngineeringAl Azhar UniversityQenaEgypt

高熵合金复合材料是一种由高熵合金基体和第二相(如碳化物、硼化物、氮化物)组成的新型金属基复合材料。近年来,高熵合金复合材料的优异性能吸引了大量研究者的关注。然而,在传统铸造高熵合金复合材料中会发生严重的成分偏析,这极大制... 详细信息

高熵合金复合材料是一种由高熵合金基体和第二相(如碳化物、硼化物、氮化物)组成的新型金属基复合材料。近年来,高熵合金复合材料的优异性能吸引了大量研究者的关注。然而,在传统铸造高熵合金复合材料中会发生严重的成分偏析,这极大制约了高熵合金复合材料的发展。目前,新兴的3D打印技术可以解决这一问题并制备出复杂形状的零件,因此,得到了研究者的关注并有大量相关文献报导。本文总结了截止目前3D打印高熵合金复合材料的研究进展。首先,对高熵合金及其复合材料做了介绍,并总结了目前高熵合金复合材料粉末的制备方法(气雾化法和机械合金化法)。其次,介绍了几种常用于成形高熵合金复合材料的3D打印方法(粉末床熔化法和直接金属沉积技术),并对其相应的微观结构进行了分析。然后,对比了3D打印高熵合金复合材料、3D打印高熵合金及其铸件的力学性能,并对其硬度抗磨损、腐蚀和氧化性能进行了探讨。最后,对3D打印高熵合金复合材料的发展前景进行了展望。

关键词：高熵合金复合材料增材制造增强相微观结构力学性能

BAS-ADAM:An ADAM Based Approach to Improve the Performance of Beetle Antennae Search Optimizer

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 461-471页

作者： Ameer hamza Khan Xinwei Cao Shuai Li Vasilios N.Katsikis Liefa Liao Department of Computing Hong Kong Polytechnic UniversityHong KongChina School of Management Shanghai UniversityShanghai 201900China Department of Electronics and Electrical Engineering Swansea UniversitySwansea SA18ENUK Department of Economics Division of Mathematics and InformaticsNational and Kapodistrian University of AthensAthens 10679Greece School of Information Engineering Jiangxi University of Science and TechnologyGanzhou 341000China

In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective *** achieve this by adaptively adjusting the step-size in each iteration using the adaptive moment estimation(ADAM)update *** proposed algorithm also increases the convergence rate in a narrow valley.A key feature of the ADAM update rule is the ability to adjust the step-size for each dimension separately instead of using the same *** ADAM is traditionally used with gradient-based optimization algorithms,therefore we first propose a gradient estimation model without the need to differentiate the objective ***,it demonstrates excellent performance and fast convergence rate in searching for the optimum of noin-convex *** efficiency of the proposed algorithm was tested on three different benchmark problems,including the training of a high-dimensional neural *** performance is compared with particle swarm optimizer(PSO)and the original BAS algorithm.

关键词： Adaptive moment estimation(ADAM) Beetle antennae search(BAM) gradient estimation metaheuristic optimization nature-inspired algorithms neural network