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Optimal control of thermoelastic beam vibrations by piezoelectric actuation

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控制理论与应用（英文版） 2013年第3期11卷 463-467页

作者： ibrahim SADEK Marwan ABUKHALED Department of Mathematics and Statistics American University of Sharjah

This paper presents the vibrations suppression of a thermoelastic beam subject to sudden heat input by a single piezoelectric actuator. An optimization problem is formulated as the minimization of a quadratic functional in terms of displacement and velocity at a given time and with the least control effort. The solution method is based on a combination of modal expansion and variational approaches. The modal expansion approach is used to convert the optimal control of distributed parameter system into the optimal control of lumped parameter system. By utilizing the variational approach, an explicit optimal control law is derived and the determination of the corresponding displacement and velocity is reduced to solving a set of ordinary differential equations. Numerical results are presented to demonstrate the effectiveness and the applicability of the proposed method.

关键词： Modal expansion approach Optimal control Thermoelastic beam Piezoelectric actuation Variational approach

Synthesis of some new fused coumarin derivatives

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Chinese Journal of Chemistry 2000年第4期18卷 590-595页

作者： EL-DEEN ibrahim Mohey ibrahim H.K. MAHMOUD F.F. Faculty of Education Suez Canal University Port-Said EgyptFaculty of Science Suez Canal University Ismailia EgyptFaculty of Science (for Girls) Al-Azhar University Nasr City Egypt

2-Hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (3) was prepared via condensation of 2 with hydrazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride affording the corresponding 2-(substituted) hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).

关键词： Synthesis fused coumarin derivatives cyclization

Hidden Hierarchy Based on Cipher-Text Attribute Encryption for IoT Data Privacy in Cloud

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Computers, Materials & Continua 2023年第7期76卷 939-956页

作者： Zaid Abdulsalam ibrahim Muhammad Ilyas Department of Electrical and Computer Engineering Altinbas UniversityIstanbulTurkey Department of Computer Engineering Altinbas UniversityIstanbulTurkey

Most research works nowadays deal with real-time Internetof Things (IoT) data. However, with exponential data volume increases,organizations need help storing such humongous amounts of IoT data incloud storage systems. Moreover, such systems create security issues whileefficiently using IoT and Cloud Computing technologies. Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has the potential to make IoT datamore secure and reliable in various cloud storage services. Cloud-assisted IoTssuffer from two privacy issues: access policies (public) and super polynomialdecryption times (attributed mainly to complex access structures). We havedeveloped a CP-ABE scheme in alignment with a Hidden HierarchyCiphertext-Policy Attribute-Based Encryption (HH-CP-ABE) access structure embedded within two policies, i.e., public policy and sensitive *** this proposed scheme, information is only revealed when the user’sinformation is satisfactory to the public policy. Furthermore, the proposedscheme applies to resource-constrained devices already contracted tasks totrusted servers (especially encryption/decryption/searching). Implementingthe method and keywords search resulted in higher access policy privacy andincreased security. The new scheme introduces superior storage in comparisonto existing systems (CP-ABE, H-CP-ABE), while also decreasing storage costsin HH-CP-ABE. Furthermore, a reduction in time for key generation canalso be ***, the scheme proved secure, even in handling IoT datathreats in the Decisional Bilinear Diffie-Hellman (DBDH) case.

关键词： Bilinear Diffie-Hellman(DBDH) Internet of Things(IoT) Ciphertext-Policy Attribute-Based Encryption(CP-ABE) Hidden Hierarchy CP-ABE(HH-CP-ABE)

Chemical behaviours of 3-[1'-chloro-3'-(2"-phenyl-1",3"-oxazol-5"-one-4"-ylidene)propen-l'-yl]coumarin towards some nucleophilic reagents

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Chinese Journal of Chemistry 1998年第6期16卷 533-537页

作者： EL-DEEN ibrahim Mohey Faculty of Education Suez Canal University Port-Said EgyptFaculty of Education Suez Canal University Port-Said Egypt

The chemical behaviours of 3-[1'-chloro-3'-(2'-phenyl-1',3'-oxazol-5'-one-4'-ylidene)-propen-1'-yl]coumarin towards nucleophilic reagents (such as hydrolysis,aminolysis,hydroxyl-aminolysis,methanolysis and hydrazinoly... 详细信息

关键词： Chemical behaviours coumarin derivatives nucleophiles

New insights into astrocyte diversity from the lens of transcriptional regulation and their implications for neurodegenerative disease treatments

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Neural Regeneration Research 2024年第11期19卷 2335-2336页

作者： ibrahim Olabayode Saliu Guoyan Zhao Department of Genetics Washington University School of MedicineSt.LouisMOUSA Department of Neurology Department of Pathology and ImmunologyWashington University School of MedicineSt.LouisMOUSA

Astrocytes are a major glial cell type in the central nervous system,and they provide trophic and metabolic support to *** addition to these roles,they play crucial roles in modulating synaptic functions,development,and pruning(Brandebura et al.,2023).Astrocytes become reactive(activated)by undergoing morphological,molecular,and functional alterations in response to neuropathology such as in injuries and neurodegenerative diseases(NDs)(Escartin et al.,2021).

关键词： degenerative injuries

Keypoint Description Using Statistical Descriptor with Similarity-Invariant Regions

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Computer Systems Science & Engineering 2022年第7期42卷 407-421页

作者： ibrahim El rube Sameer Alsharif Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.o.Box 11099Taif21944Saudi Arabia

This article presents a method for the description of key points using simple statistics for regions controlled by neighboring key points to remedy the gap in existing ***,the existent descriptors such as speeded up robust features(SURF),Kaze,binary robust invariant scalable keypoints(BRISK),features from accelerated segment test(FAST),and oriented FAST and rotated BRIEF(ORB)can competently detect,describe,and match images in the presence of some artifacts such as blur,compression,and ***,the performance and reliability of these descriptors decrease for some imaging variations such as point of view,zoom(scale),and *** intro-duced description method improves image matching in the event of such *** utilizes a contourlet-based detector to detect the strongest key points within a speciﬁed window *** selected key points and their neighbors con-trol the size and orientation of the surrounding regions,which are mapped on rec-tangular shapes using polar *** resulting rectangular matrices are subjected to two-directional statistical operations that involve calculating the mean and standard ***,the descriptor obtained is invariant(translation,rotation,and scale)because of the two methods;the extraction of the region and the polar transformation techniques used in this *** descrip-tion method introduced in this article is tested against well-established and well-known descriptors,such as SURF,Kaze,BRISK,FAST,and ORB,techniques using the standard OXFORD *** presented methodology demonstrated its ability to improve the match between distorted images compared to other descriptors in the literature.

关键词： Keypoint detection descriptors neighbor region similarity invariance

Application of microfluidic technology based on surface-enhanced Raman scattering in cancer biomarker detection:A review

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Journal of Pharmaceutical Analysis 2023年第12期13卷 1429-1451页

作者： Changhong Nie ibrahim Shaw Chuanpin Chen Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha410013China

With the continuous discovery and research of predictive cancer-related biomarkers,liquid biopsy shows great potential in cancer ***-enhanced Raman scattering(SERS)and microfluidic technology have received much attention among the various cancer biomarker detection *** former has ultrahigh detection sensitivity and can provide a unique *** contrast,the latter has the characteristics of miniaturization and integration,which can realize accurate control of the detection samples and high-throughput detection through *** have the potential for point-of-care testing(POCT),and their combination(lab-on-a-chip SERS(LoC-SERS))shows good *** this paper,the basic situation of circulating proteins,circulating tumor cells,exosomes,circulating tumor DNA(ctDNA),and microRNA(miRNA)in the diagnosis of various cancers is reviewed,and the detection research of these biomarkers by the LoC-SERS platform in recent years is described in *** the same time,the challenges and future development of the platform are discussed at the end of the *** the current technology is expected to provide a reference for scholars engaged in related work and interested in this field.

关键词： Cancer biomarkers Microfluidic technology Surface-enhanced Raman scattering

Generalized thermoelasticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli

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Chinese Physics B 2012年第1期21卷 289-294页

作者： ibrahim A.Abbas Mohamed I.A.Othman Department of Mathematics Faculty of Science and Arts-KhulaisKing AbdulAziz UniversityJeddahSaudi Arabia Department of Mathematics Faculty of ScienceSohag UniversitySohagEgypt Department of Mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

In this paper, we construct the equations of generalized thermoelasicity for a non-homogeneous isotropic hollow cylider with a variable modulus of elasticity and thermal conductivity based on the Lord and Shulman theory. The problem has been solved numerically using the finite element method. Numerical results for the displacement, the temperature, the radial stress, and the hoop stress distributions are illustrated graphically. Comparisons are made between the results predicted by the coupled theory and by the theory of generalized thermoelasticity with one relaxation time in the cases of temperature dependent and independent modulus of elasticity.

关键词： generalized thermoelsticity thermal shock temperature dependent elastic moduli finiteelement method

Proactive Load Balancing Mechanism for Fog Computing Supported by Parked Vehicles in IoV-SDN

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China Communications 2021年第2期18卷 271-289页

作者： Ahmed Jawad Kadhim Jaber ibrahim Naser Ministry of Education General Directorate for Education in Al-QadisiyahAl-Qadisiyah 58002Iraq

Internet of Vehicles(IoV)is a new style of vehicular ad hoc network that is used to connect the sensors of each vehicle with each other and with other vehicles’sensors through the *** sensors generate different tasks that should be analyzed and processed in some given period of *** send the tasks to the cloud servers but these sending operations increase bandwidth consumption and *** computing is a simple cloud at the network edge that is used to process the jobs in a short period of time instead of sending them to cloud computing *** some situations,fog computing cannot execute some tasks due to lack of ***,in these situations it transfers them to cloud computing that leads to an increase in latency and bandwidth occupation ***,several fog servers may be fuelled while other servers are *** implies an unfair distribution of *** this research study,we shall merge the software defined network(SDN)with IoV and fog computing and use the parked vehicle as assistant fog computing *** can improve the capabilities of the fog computing layer and help in decreasing the number of migrated tasks to the cloud *** increases the ratio of time sensitive tasks that meet the *** addition,a new load balancing strategy is *** works proactively to balance the load locally and globally by the local fog managers and SDN controller,*** simulation experiments show that the proposed system is more efficient than VANET-Fog-Cloud and IoV-Fog-Cloud frameworks in terms of average response time and percentage of bandwidth consumption,meeting the deadline,and resource utilization.

关键词： IoV parked vehicles SDN fog computing load balancing