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2022 International Telecommunications Conference, ITC-Egypt 2022

作者： Ahmed, Hayder S. Ahmed, Zahraa Salah Zamel, Rafid S. Elwi, Taha Ahmed Al-Esraa University College Department of Biomedical Engineering Baghdad Iraq University of Technology Applied physics school Baghdad Iraq Al-Ma'moon University College Department of Communication Engineering Baghdad Iraq

ISBN: (数字)9781665488082

ISBN: (纸本)9781665488082

In this paper, a compact multi-input multi-output (MIMO) microstrip antenna is proposed by using hayder fractal geometry. The proposed structure is derived from Koch fractal geometry to provide a further flexibility in the design process to tune the antenna frequency resonance parameters. Therefore, a compacted MIMO antenna array is resulted with high isolation at center frequency of 28 GHz when mounted on Rogers5880 substrate of 0.787mm thickness and a dielectric constant of 2.2. CST Microwave Studio is invoked to investigate the simulation antenna performance in terms of S-permeates and radiation properties. For validation, the performance of the proposed antenna array is tested inside another electromagnetic software package (Microwave Office 'MWO'). The simulated results from the two used software packages are agreed acceptably. © 2022 IEEE.

关键词： Antenna arrays

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Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： M.K.h.Hamad Nidal Dwaikat M.H.A.Mhareb M.I.Sayyed R.M.Hamad Y.S.M.Alajerami M.A.Almessiere Gameel Saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear Medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia Medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&Minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOM computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding Mass stopping power Rare earths

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Accuracy of DFT computed oxygen-vacancy formation energies and high-throughput search of solar thermochemical water-splitting compounds

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Physical Review Materials 2023年第6期7卷 065403-065403页

作者： Bianca Baldassarri Jiangang He Xin Qian Emanuela Mastronardo Sean Griesemer Sossina M. Haile Christopher Wolverton Graduate Program in Applied Physics Northwestern University Evanston Illinois USA Department of Materials Science and Engineering Northwestern University Evanston Illinois USA

The enthalpy change involved in metal oxide reduction is a key quantity in various processes related to energy conversion and storage and is of particular interest for computational prediction. Often this prediction involves the simulation of a high-temperature reduction process with a 0-K methodology like density functional theory (DFT), and it is not infrequent for the high temperature and 0-K stable crystal structures to differ. This introduces a conundrum with regard to the choice of crystal structure to utilize in the computation, with approaches in the literature varying and experimental validation remaining scarce. In this work, we address both the crystal structure conundrum and the experimental validation, and then apply the insights we gain to guide a high-throughput search for new materials for solar thermochemical water-splitting applications. By computing the DFT+U oxygen-vacancy formation energy (ΔEvf) of a selection of ABO3 compounds and comparing different crystal structures for each composition, we highlight the issues that arise when the structure utilized in the computation is dynamically unstable at 0 K, namely the presence of an artificial lowering of ΔEvf, and the lack of convergence of ΔEvf with cell size. We solve these limitations by identifying and employing a suitable surrogate dynamically stable structure. We then validate the predictive power of our calculations against appositely generated experimental measurements of reduction enthalpy for a series of Hubbard U values, finding an accuracy ranging between 0.2–0.6 eV/O. In light of such conclusions, we revise and expand a previous a high-throughput DFT study on ABO3 perovskite oxides. We provide a list of candidate STCH materials, highlight trends with redox-active cation and structural distortion, and identify Mn4+, Mn3+, and Co3+ as the most promising redox-active cations.

关键词： Energy applications First-principles calculations Hydrogen energy

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Optimizing BI-RADS 4 Lesion Assessment Using Lightweight Convolutional Neural Network with CBAM in Contrast Enhanced Mammography 1st

Optimizing BI-RADS 4 Lesion Assessment Using Lightweight Con...

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1st Deep Breast Workshop on AI and Imaging for Diagnostic and Treatment Challenges in Breast Care, Deep-Breath 2024

作者： Oladimeji, Oladosu Ayaz, Hamail McLoughlin, Ian Unnikrishnan, Saritha Faculty of Engineering and Design Atlantic Technological University Sligo Ireland Health and Biomedical Strategic Research Centre Atlantic Technological University Sligo Ireland Faculty of Engineering and Design Atlantic Technological university SligoF91 YW50 Ireland Department of Computer Science and Applied Physics Atlantic Technological university Galway Ireland

ISBN: (纸本)9783031777882

Breast cancer is the leading cause of cancer-related mortality and morbidity among women worldwide. Early detection plays a crucial role in improving survival rates and BI-RADS classification is one of the effective ways of predicting breast cancer. However, BI-RADS Category 4 encompasses a broad spectrum of malignancy probabilities, ranging from over 2% to 95%. Due to the wide malignancy likelihood range and the ambiguous qualitative attributes of BI-RADS 4, patients are subjected to overdiagnosis and unnecessary procedures, such as biopsy, which entail a certain degree of physical trauma as well as financial strain. This study proposed a lightweight CNN where MobileNet serves as the backbone architecture, augmented with the Convolutional Block Attention Module (CBAM), resulting in the MobileNet-CBAM model. The model demonstrated good performance in discriminating BI-RADS 4 category malignant and benign cases in Contrast Enhanced Spectral Mammogram (CESM) with a prediction of 82%, 82% and 0.91 for accuracy, f1-score and roc-auc respectively. Additionally, for clinical friendliness, the model explanation was given using SHAP. Hence, the model presents potential utility in predicting breast cancer for lesions categorized as BI-RADS category 4 in breast imaging. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

关键词： Convolution

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Color-fast semi-transparent organic photovoltaics 25

Color-fast semi-transparent organic photovoltaics

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Organic Photonic Materials and Devices XXV 2023

作者： Sheriff, Hafiz K.M. Li, Yongxi Forrest, Stephen R. Applied Physics Program University of Michigan Ann ArborMI48109 United States Department of Electrical Engineering University of Michigan Ann ArborMI48109 United States Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States Department of Physics University of Michigan Ann ArborMI48109 United States

ISBN: (纸本)9781510659414

Equipping buildings with energy harvesting windows is a practical way to reduce greenhouse gas (GhG) emission. Utilizing semi-transparent organic photovoltaics (ST-OPVs) for this application requires the device to be colorfast, allowing for no change in the aesthetics or light harvesting property of the window. Here, we demonstrate an ST-OPV that is colorfast under 1 Sun AM 1.5G illumination at 50 °C and relative humidity of 34 %. © 2023 SPIE.

关键词： Energy harvesting

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Imaging and Understanding 3D Nanoscale Magnetic Structures

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Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada 2023年第1期29卷 1398-1399页

作者： Petford-Long, Amanda K. Brajuskovic, Vuk Li, Yue McCray, Arthur R C Phatak, Charudatta Materials Science Division Argonne National Laboratory Lemont IL United States Materials Science and Engineering Department Northwestern University Evanston IL United States Applied Physics Program Northwestern University Evanston IL United States

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Performance Optimization of Series Resonant Converter by Combined Frequency and Duty Ratio Control

Performance Optimization of Series Resonant Converter by Com...

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On-Line Conference (ONCON), Industrial Electronics Society Annual

作者： Soham Chakraborty Supratik Bhowmick Suman Maiti Department of Applied Physics UG Program of Electrical Engineering Calcutta University Kolkata India Department of Electrical Engineering Indian Institute of Technology Kharagpur Kharagpur India

ISBN: (数字)9798331540319

ISBN: (纸本)9798331540326

Resonant converters are widely used for voltage regulator applications. The basic converters i.e., Series resonant Converter (SRC) and Parallel Resonant Converter (PRC) are having some merits and limitations. These are addressed in multi element topologies at the cost of adding extra elements. This work takes up the SRC and reports a combined frequency and duty ratio control for performance optimization of the SRC. The key issue of SRC is that the voltage cannot be controlled at a low Q (i.e. Quality factor) operation. For example, at no load Q becomes zero making the converter inert to frequency variation. This however can be eliminated by pulse width modulation technique. Duty ratio can be properly controlled to achieve the output voltage at an extended load range. The work further takes up challenge to make efficiency optimized. For this a combined control of duty ratio and frequency are proposed. Efficiency Optimization Control (EOC) requires two voltage sensors (one at the input side and another at the output) and a current sensor. Following this, a new minimum rms current algorithm is developed that only requires a current and a voltage sensor. All the proposed techniques are simulated and verified using MATLAB/Simulink.

关键词： Q-factor Frequency modulation Resonant frequency Resonant converters Frequency conversion Sensors Topology Voltage control Frequency control Optimization

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A New Pulse Skipping Control for Series Resonant Converter

A New Pulse Skipping Control for Series Resonant Converter

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On-Line Conference (ONCON), Industrial Electronics Society Annual

作者： Supratik Bhowmick Soham Chakraborty Suman Maiti Department of Electrical Engineering Indian Institute of Technology Kharagpur Kharagpur India Department of Applied Physics UG Program of Electrical Engineering Calcutta University Kolkata India

ISBN: (数字)9798331540319

ISBN: (纸本)9798331540326

This paper proposes a pulse skipping based combined frequency and duty ratio control for a series resonant converter which is targeted for voltage regulator applications. The proposed pulse skipping control combines duty ratio based phase shifted control for maintaining output voltage at its reference value, along with frequency based control which assists in development of the pulse skipping algorithm. This algorithm is structured so that pulses are skipped in generated gate pulses for upper switching devices present in the converter whenever the output voltage tries to be higher than its specified maximum value or be lower than its specified minimum value. These maximum and minimum voltages are determined based on its reference voltage and allowable voltage ripple within which the oscillations in output voltage are desired to be in. The converter system with the proposed control method is simulated in MATLAB/Simulink environment to validate its performance under transient conditions e.g., variation in load resistance and output voltage reference. The system performance with proposed method is also compared with conventional method where the proposed control demonstrates its superiority by significantly minimizing the output voltage ripple.

关键词： Resistance Resonant frequency Resonant converters Logic gates Frequency conversion Voltage control Transient analysis MATLAB Frequency control Oscillators

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Ronchigram Simulation and Aberration Correction Training using ***

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Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada 2023年第1期29卷 1911-1912页

作者： Millsaps, William Sung, Suk Hyun Schnitzer, Noah Kourkoutis, Lena F. Hovden, Robert Engineering Physics Program University of Michigan Ann Arbor MI United States Department of Materials Science and Engineering University of Michigan Ann Arbor MI United States Department of Materials Science and Engineering Cornell University Ithaca NY United States School of Applied and Engineering Physics Cornell University Ithaca NY United States Kavli Institute at Cornell for Nanoscale Science Cornell University Ithaca NY United States

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TiO2 Hole Transport Layer Incorporated in a Thermally Evaporated Sb2Se3 Photoelectrode Exhibiting Low Onset Potential for Photoelectrochemical Applications

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Energy and Fuels 2024年第17期38卷 16936-16948页

作者： Xavier, Thatheyus Peter Piraviperumal, Malar Kuo, Chih-Yu Govindasamy, Mani Thinfilm Photovoltaics Laboratory Department of Physics and Nanotechnology SRM Institute of Science and Technology Tamil Nadu Kattankulathur603203 India Department of Chemical Engineering & Biotechnology National Taipei University of Technology Taipei City10608 Taiwan Research Center for Intelligence Medical Devices Ming Chi University of Technology New Taipei City243303 Taiwan Department of Research and Innovation Saveetha School of Engineering SIMATS Chennai602105 India Taipei10608 Taiwan International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices Ming Chi University of Technology New Taipei City243303 Taiwan

Developing cost-effective photoelectrodes with a low band gap in the NIR-visible regions remains a challenge to achieve effective hydrogen production. We report the details of superstrate-configured photocathodes, consisting of antimony selenide (Sb2Se3) light absorbing layers with titanium dioxide (TiO2) as a hole transport layer, exhibiting the capability for hydrogen evolution with broad range light absorption enabled by the low band gap value of ∼1.2 eV of Sb2Se3. Strong anisotropy is a significant characteristic property of Sb2Se3, allowing superior electrical transportation along the [hkl] crystallographic orientation, which is obtained via close space evaporation of presynthesized bulk material at a growth temperature of 250 °C, over the solution-processed TiO2 film on a fluorine-doped tin oxide (FTO) substrate. The superstrate-configured FTO/TiO2/Sb2Se3 photocathode exhibited a photocurrent density of 100 μA cm-2 at −0.3 V vs RHE in 0.5 M H2SO4 under 1 sun illumination. To further improve photocurrent density, Pt as a cocatalyst was deposited over Sb2Se3 that led to enhanced photocurrent to 3 mA cm-2 at −0.3 V vs RHE in 0.5 M H2SO4 under 1 sun illumination. Despite the relatively lower photocurrent observed, which resulted due to a large conduction band offset (ΔECB = 0.99 eV) of the TiO2/Sb2Se3 interface in a superstrate configuration, a significantly lower onset potential of −0.1 V vs RHE was observed. The results are encouraging due to the low band gap of Sb2Se3, photocorrosion stability, and straightforward fabrication, which is expected to assist for significant outcomes. © 2024 American Chemical Society.

关键词： Titanium dioxide

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