检索结果-南通市图书馆

The effect of multi-intermediate bands on the behavior of an InAs_(1-x)N_x/GaAs(1-y)Sb_y quantum dot solar cell

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第4期36卷 1-6页

作者： Abou El-Maaty M.Aly a.nasr Power Electronics and Energy Conversion Department ERINRCB College of Computer Qassim University Radiation Engineering Department NCRRTAtomic Energy Authority

A mathematical model of quantum dot intermediate band solar cells （QDIBSCs） is investigated using two intermediate bands （IBs）. These two IBs arise from the quantum dot （QD） semiconductor material within the bandgap energy. Some parameters such as the width of the QD （WQD） and the barrier thickness or the inter-dot distances between the QDs （BT） are studied to show their influence on the performance of the QDIBSC. The timeindependent Schr6dinger equation, which is solved using the Kronig-Penney model, is used to determine the posi- tion and bandwidth energies of the two IBs. In our proposed model, the cubic shape of the QDs from InAs0.9N0.1 and the barrier or host semiconductor material from GaAs0.98Sb0.02 are utilized. It is shown from the results obtained that changing the parameters WQD and Bx has more influence on the bandwidth energy for the first IB, A 1, than in the case of the second IB, A2. The optimum power conversion efficiencies （PCEs） of the QDIBSCs with two IBs for the model under study are 58.01% and 73.55% at 1 sun and maximum solar concentration, respectively. One can observe that, in the case of the two IBs, an improvement of the PCE is achieved.

关键词： intermediate bands solar cells quantum dots efficiency solar concentration

Lower extremity injuries in vehicle-pedestrian collisions using a legform impactor model

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 97-105页

作者： A.ABVABI a.nasr A.NOORPOOR M.S.KIASAT Department of Automotive Engineering Iran University of Science and TechnologyTehranIran School of Railway Engineering Iran University of Science and TechnologyTehranIran Faculty of Marine Technology Amirkabir University of TechnologyTehranIran

Though the bumper of a vehicle plays a major role in protecting the vehicle body against damage in low speed impacts, many bumpers, particularly in large vehicles, are too stiff for pedestrian protection. In designing a bumper for an automobile, pedestrian protection is as important as bumper energy absorption in low speed collisions. To prevent lower extremity injuries in car-pedestrian collisions, it is important to determine the loadings that car front structures impart on the lower extremities and the mechanisms by which injury is caused by these loadings. The present work was focused on gaining more insight into the injury mechanisms leading to both ligament damage and bone fracture during bumper-pedestrian collisions. The European Enhanced Vehicle-safety Committee （EEVC） legform impactor model was introduced and validated against EEVCAVG17 criteria. The collision mechanism between a bumper and this legform impactor was investigated numerically using LS-DYNA software. To identify the effect of the bumper beam material on leg injuries, four analyses were performed on bumpers that had the same assembly but were made from different materials.

关键词： Finite element model (FEM) Legform impactor Pedestrian safety Lower extremity injury Composite bumper

A New Reliable System For Managing Virtual Cloud Network

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第12期73卷 5863-5885页

作者： Samah Alshathri Fatma M.Talaat Aida a.nasr Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikhEgypt Faculity of Computers and Informatics Tanta UniversityTantaEgypt

Virtual cloud network(VCN)usage is popular today among large and small organizations due to its safety and ***,it makes all resources in the company work as one *** also facilitates sharing of files and applications without ***,cloud providers face many issues in managing the VCN on cloud computing including these issues:Power consumption,network failures,and data *** issues often occur due to overloaded and unbalanced load *** this paper,we propose a new automatic system to manage VCN for executing the *** new system calledMulti-User Hybrid Scheduling(MUSH)can solve running issues and save power during workflow *** consists of three phases:Initialization,virtual machine allocation,and task scheduling *** MUSH system focuses on the execution of the workflow with deadline ***,it considers the utilization of virtual *** new system can save makespan and increase the throughput of the execution operation.

关键词： Virtual network scheduling reliability VM allocation cloud computing

Thermal oil recovery factors from sandpacks of variable mineralogy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Research 2023年第4期8卷 481-489页

作者： Viacheslau Y.Kudrashou Hisham a.nasr-El-Din Slippery Rock University United States Texas A&M University United States

S Steam injection is commonly used for production of viscous crude *** rock often contains clay *** nature of steam and clay minerals may lead to formation *** work in-vestigates oil recovery and changes in petrophysical properties as a function of the ***-packs with quartz,calcite,feldspar,kaolinite,smectite,and illite were prepared for steam injection *** of the steamed sandpacks was determined using coreflood *** composition of the produced aqueous samples was determined using ICP-OES(inductively coupled plasma-optical emission spectroscopy).Morphology of the rock samples was studied using SEM-EDs(scanning electron microscope-energy dispersive X-ray spectroscopy).Mineralogy and elemental content of the solid samples were determined using XRD(X-ray diffraction)analysis and XRF(X-ray fluorescence)*** was found that aqueous phase samples produced from clay-rich sandpacks tend to have higher pH than samples produced from samples without clay *** recovery factors for 100%quartz case was determined to be 65 wt%.Calcite-and feldspar-rich sandpacks produced 56 and 61 wt%of oil *** with clay fractions have shown the lowest oil recovery-39,29,and 28 wt%for kaolinite-,smectite-,and illite-rich samples *** dissolution and pre-cipitation were the dominant damaging mechanism for quartz and calcite ***-rich sandpack demonstrated signs of structural destruction of the mineral and fines ***'s effect on oil recovery was found to be associated with fines *** hydration and swelling in presence of steam was the dominant formation damage effect on the oil *** interaction with illite-rich sandpack caused formation of amorphous *** paper presents oil recovery factors as a function of injected pore volume(PV)of steam for sandpacks of different *** results characterize petroph

关键词： Steam injection Oilrecovery Kaolinite Smectite Ilite Sandpack

A Robust Video Watermarking Scheme with Squirrel Search Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第5期71卷 3069-3089页

作者： Aman Bhaskar Chirag Sharma Khalid Mohiuddin Aman Singh Osman a.nasr Mamdooh Alwetaishi Computer Science and Engineering Lovely Professional UniversityPunjab144411India Department of Management Information Systems King Khalid UniversityGuraigerAbha62529Saudi Arabia Department of Civil Engineering College of EngineeringTaif UniversityTaif21944Saudi Arabia

Advancement in multimedia technology has resulted in protection against distortion,modification,and *** implementing such protection,we have an existing technique called watermarking but obtaining desired distortion level with sufficient robustness is a challenging task for watermarking in multimedia *** the paper,we proposed a smart technique for video watermarking associating meta-heuristic algorithms along with an embedding method to gain an optimized *** main aim of the optimization algorithm is to obtain solutions with maximum robustness,and which should not exceed the set threshold of *** represent the accuracy of the proposed scheme,we employ a popular video watermarking technique(DCT domain)having frame selection and embedding method for watermarking.A squirrel search algorithm is chosen as a meta-heuristic algorithm that utilizes the stated fitness *** results indicate that quality constraint is fulfilled,and the proposed technique gives improved robustness against different attacks with several quality *** proposed technique could be practically implemented in several multimedia applications such as the films industry,medical imagery,OOT platforms,etc.

关键词： Meta-heuristic algorithm constrain optimization problem fitness fiction frame selection squirrel search algorithm

Robust Machine Learning Mapping of sEMG Signals to Future Actuator Commands in Biomechatronic Devices

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第1期21卷 270-287页

作者： Ali nasr Sydney Bell Rachel L.Whittaker Clark R.Dickerson John McPhee Systems Design Engineering University of WaterlooWaterloo N2L 3G1Canada Kinesiology and Health Sciences University of WaterlooWaterloo N2L3G3Canada

A machine learning model for regression of interrupted Surface Electromyography(sEMG)signals to future control-oriented signals(e.g.,robot’s joint angle and assistive torque)of an active biomechatronic device for high-level myoelectric-based hierarchical control is proposed.A Recurrent Neural Network(RNN)was trained using output data,initially obtained from offline optimization of the biomechatronic(human–robot)device and shifted by the prediction *** input of the RNN consisted of interrupted sEMG signals(to mimic signal disconnections)and previous kinematic signals of the assistive *** RNN with a 0.1-s prediction horizon could predict the control-oriented joint angle and assistive torque with 92%and 86.5%regression accuracy,respectively,for the test *** proposed approach permits a fast,predictive,and direct estimation of control-oriented signals instead of an iterative process that optimizes assistive torque in the inverse dynamic simulation of a multibody human–robot *** with these interrupted input signals significantly improves the regression accuracy in the case of sEMG signal *** Robust Predictive Control-oriented Machine Learning(Robust-MuscleNET)model can support volitional high-level myoelectric-based control of biomechatronic devices,such as exoskeletons,prostheses,and assistive/resistive *** work should study the application to prosthesis control as well as the repeatability of the high-level controller with electrode *** low-level hierarchical controller that manages the human–robot interaction,the assistance/resistance strategy,and the actuator coordination should also be studied.

关键词： Myoelectric-based control-Surface electromyography Machine learning Multibody system dynamics Exoskeleton Bionic

Advances in clinical applications of bioceramics in the new regenerative medicine era

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第11期12卷 1863-1869页

作者： Noha Elshazly Fayza Eid nasr Ayat Hamdy Safa Saied Mohamed Elshazly Tissue Engineering Laboratory Faculty of DentistryAlexandria UniversityAlexandria 21526Egypt Department of Biochemistry Faculty of ScienceAlexandria UniversityAlexandria 21526Egypt Public Dental Clinic Central Administration of DentistryMinistry of Health and PopulationAlexandria 21554Egypt Department of Surgery Faculty of Veterinary MedicineAlexandria 21526Egypt

In this editorial,we comment on the hard and soft tissue applications of different ceramic-based scaffolds prepared by different mechanisms such as 3D printing,sol-gel,and *** new concept of regenerative medicine relies on biomaterials that can trigger in situ tissue regeneration and stem cell recruitment at the defect site.A large percentage of these biomaterials is ceramic-based as they provide the essential requirements of biomaterial principles such as tailored multisize porosity,antibacterial properties,and angiogenic *** these previously mentioned properties put bioceramics on top of the hierarchy of biomaterials utilized to stimulate tissue regeneration in soft and hard tissue *** clinical applications registered the use of these materials in triggering soft tissue regeneration in healthy and diabetic patients such as bioactive glass *** results were promising and opened new frontiers for utilizing these materials on a larger *** same results were mentioned when using different forms and formulas of bioceramics in hard defect *** bioceramics were used in combination with other polymers and biological scaffolds to improve their regenerative and mechanical *** this progress will enable a larger scale of patients to receive such services with ease and decrease the financial burden on the government.

关键词： Regenerative medicine Bioceramics Chronic wounds Bone defects Clinical applications

Engineering nanomedicines for immunogenic eradication of cancer cells:Recent trends and synergistic approaches

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第6期14卷 2475-2504页

作者： Ahmed O.Elzoghby Omar Samir Hagar E.Emam Ahmed Soliman Riham M.Abdelgalil Yomna M.Elmorshedy Kadria A.Elkhodairy Mahmoud L.nasr Division of Engineering in Medicine and Division of Renal Medicine Department of MedicineBrigham and Women's HospitalHarvard Medical SchoolBoston 02115MAUSA Cancer Nanotechnology Research Laboratory(CNRL) Faculty of PharmacyAlexandria UniversityAlexandria 21521Egypt

Resistance to cancer immunotherapy is mainly attributed to poor tumor immunogenicity as well as the immunosuppressive tumor microenvironment(TME)leading to failure of immune *** therapeutic strategies including chemotherapy,radiotherapy,photodynamic,photothermal,magnetic,chemodynamic,sonodynamic and oncolytic therapy,have been developed to induce immunogenic cell death(ICD)of cancer cells and thereby elicit immunogenicity and boost the antitumor immune ***,many challenges hamper the clinical application of ICD inducers resulting in modest immunogenic ***,we outline the current state of using nanomedicines for boosting ICD of cancer ***,synergistic approaches used in combination with ICD inducing nanomedicines for remodeling the TME via targeting immune checkpoints,phagocytosis,macrophage polarization,tumor hypoxia,autophagy and stromal modulation to enhance immunogenicity of dying cancer cells were *** further highlight the emerging trends of using nanomaterials for triggering amplified ICD-mediated antitumor immune *** reticulum localized ICD,focused ultrasound hyperthermia,cell membrane camouflaged nanomedicines,amplified reactive oxygen species(ROS)generation,metallo-immunotherapy,ion modulators and engineered bacteria are among the most innovative *** challenges,merits and demerits of ICD inducer nanomedicines were also discussed with shedding light on the future role of this technology in improving the outcomes of cancer immunotherapy.

关键词： Immunogenic cell death Immunogenic eradication Nanomedicines Drug delivery Cancer immunotherapy Antitumor immunity T cells Tumor associated antigens Synergistic immune response

Intravesical instillation of platelet-rich plasma for treatment of interstitial cystitis/bladder pain syndrome:A pilot study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Urology 2024年第1期18卷 49-54页

作者： Ahmed S.El Hefnawy Mohamed Attya Ahmed Hasan Esam El Sawy Mohamed Abdel-Razik nasr El-Tabey Mansoura Urology and Nephrology Center Faculty of MedicineMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the feasibility of intravesical instillation of platelet-rich plasma(PRP)to treat interstitial cystitis/bladder pain syndrome(IC/BPS).Materials and methods:Twenty PRP samples were tested in vitro for stability after exposure to urine samples with different pH.A pilot study involving 21 female patients with IC/BPS was conducted,and 6 weekly doses of autologous PRP(50 mL)were *** were followed up at the 2nd,4th,8th,and 12th weeks after terminating *** primary endpoint was the visual analog scale(VAS)for pain,and the secondary endpoints included the IC symptom index,IC problem index of the O'Leary-Sant questionnaire and global response assessment,urine culture,and *** was defined as a reduction in VAS by 30%or more compared with basal level,and adverse events were ***:The mean±SD of VAS was significantly reduced compared with basal level(4.4±2.6 vs.8.8±1.1,respectively,p=0.001).Meanwhile,80%of cases were considered successful,with a 50.1%reduction in the mean score compared with the basal *** mean±SD of IC symptom index and IC problem index significantly improved compared with the basal *** response assessment was markedly,moderately,and slightly improved in 2(10%),10(50%),and 5(25%)patients,respectively,and showed no change in 3(15%).Three patients had positive urine cultures at follow-up,but 1 withdrew after 2 sessions because of a lack of ***:Repeated intravesical instillation of PRP could be considered an effective and safe approach for treating IC/BPS.

关键词： Bladder pain syndrome Interstitial cystitis Platelet-rich plasma