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arXiv 2024年

作者： Yang, Ying Liu, Tong-Hua Huang, Jiayuan Cheng, Xiaolan Biesiada, Marek Wu, Shu-Min Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and Electronics Hunan University of Science and Technology Xiangtan411201 China School of Physics and Optoelectronic Yangtze University Jingzhou434023 China National Centre for Nuclear Research Pasteura 7 WarsawPL-02-093 Poland Department of Physics Liaoning Normal University Dalian116029 China

The different spatial curvatures of the universe affect the measurement of cosmological distances, which may also contribute to explaining the observed dimming of type Ia supernovae. This phenomenon may be caused by the opacity of the universe. Similarly, the opacity of the universe can lead to a bias in our measurements of curvature. Thus, it is necessary to measure cosmic curvature and opacity simultaneously. In this paper, we propose a new model-independent method to simultaneously measure the cosmic curvature and opacity by using the latest observations of HII galaxies acting as standard candles and the latest Hubble parameter observations. The machine learning method-Artificial Neural Network is adopted to reconstruct observed Hubble parameter H(z) observations. Our results support a slightly opaque and flat universe at 1σ confidence level by using previous 156 HII regions sample. However, the negative curvature is obtained by using the latest 181 HII regions sample in the redshift range z ∼ 2.5. More importantly, we obtain the simultaneous measurements with precision on the cosmic opacity ∆τ ∼ 10−2 and curvature ∆ΩK ∼ 10−1. A strong degeneracy between the cosmic opacity and curvature parameters is also revealed in this analysis. © 2024, CC BY.

关键词： Opacity

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Practical considerations in using a binary pseudorandom array for instrument transfer function calibration 5

Practical considerations in using a binary pseudorandom arra...

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Applied Optical Metrology V 2023

作者： Takacs, P.Z. Rochester, S. Lacey, I. Munechika, K. Griesmann, U. Yashchuk, V.V. Surface Metrology Solutions LLC 19 S 1st St Unit B901 MinneapolisMN55401 United States Rochester Scientific LLC 2041 Tapscott Avenue El CerritoCA94530 United States Advanced Light Source LBNL 1 Cyclotron Road BerkeleyCA94720 United States HighRI Optics Inc. 5401 Broadway Terr St. 304 OaklandCA94618 United States National Institute of Standards and Technology Sensor Science Division GaithersburgMD20899 United States

ISBN: (纸本)9781510665583

Binary pseudo-random array (BPRA) artifacts are useful devices for calibrating the instrument transfer function (ITF) of interferometric microscopes and other optical and non-optical surface and wavefront measurement instruments. The intrinsic white noise character of the power spectral density function of the artifact simplifies the deconvolution of the ITF from the measured power spectral density (PSD). However, resampling of the BPRA intrinsic artifact features with the measurement tool's specific sampling pattern modifies the white noise character of the intrinsic spectrum and needs to be accounted for in the ITF-based data deconvolution process. We have developed an analytic solution to the spectrum of a resampled one- and two- dimensional BPRA. The resultant nominal PSD function is a simple twoparameter cosine function with a period equal to the resampled pixel width. A transfer function model for interferometric microscopes that incorporates this function, along with an ITF that includes aliasing effects and variable numerical aperture (NA), wavelength, and obscuration factor, is used to fit to the BPRA PSDs measured by an interference microscope for a range of objective and zoom lens magnification combinations. © 2023 SPIE. All rights reserved.

关键词： Power spectral density

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Uncertainty Budget in the Ldv-Based Radius Measurement

SSRN

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SSRN 2024年

作者： Shi, Shengyu Wu, Yongwei Li, Xiang Yin, Xiaochun Kuschmierz, Robert Czarske, Jürgen National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing Engineering Ministry of Education Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing School of Mechanical and Automobile Engineering South China University of Technology Guangzhou510640 China Laboratory for Measurement and Sensor System Techniques Technische Universität Dresden Dresden01069 Germany

Laser Doppler velocimeter (LDV) allows for the measurement of the lateral velocity of a rotating cylindrical workpiece, thus, enabling the absolute radius measurement, showing great application prospect. However, several adverse factors exist that decrease the measurement accuracy, for example, the variation of the fringe spacing, the variation of the rotating frequency, the spindle error motions, and the Doppler frequency estimation, which, unfortunately, have been seldom studied. In this context, this paper comprehensively analyzes the uncertainty in the LDV-based radius measurement. First, we construct an LDV sensor and calibrate its fringe spacing. Then, the LDV-based radius measurement is modeled as an algebraic equation, suggesting that the radius is indirectly measured from several input quantities, including the Doppler frequency, the fringe spacing, and the rotation frequency, each of which owns an input uncertainty, propagating into the measurement result. Ultimately, a detailed budget for the measurement uncertainty is provided. © 2024, The Authors. All rights reserved.

关键词： Laser Doppler velocimeters

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Development of a paper-based wearable UV photo-detector device using ZnO nanostructure

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Materials Today: Proceedings 2023年 92卷 951-954页

作者： Pooja M. Khanzode Devidas I. Halge Nabeel M. S. Kaawash Mohammed Y. H. Thabit Vijaykiran N. Narwade Jagdish W. Dadge Shailendra S. Dahiwale Kashinath A. Bogle Thin Film and Devices Laboratory School of Physical Sciences Swami Ramanand Teerth Marathwada University Nanded 431606 India RUSA Centre for Advanced Sensor Technology Dr. Babasaheb Ambedkar Marathwada University Aurangabad 431 004 India Department of Physics College of Engineering Pune 411005 India Department of Physics Savitribai Phule Pune University Pune 411007 India

We depict an exceedingly low-cost and flexible photodetector in this work employing ZnO nanostructures grown on Whatman filter paper as the substrate and pencil-drawn graphite as the electrodes with a gap of 1 mm between the electrodes. A semi-non-aqueous solution containing Zinc acetate ((CH 3 COO) 2 Zn·2H 2 O) is used to deposit ZnO thin film on paper. The graphite/ZnO/graphite device shows a noticeable increase in the photo-current under UV (253 nm) light of the intensities in the range from 6 to 100 µW/cm 2 with a higher I p /I d ratio of 7800 at 30 V. This device shows higher responsivity of 1.94 A/W for the lowest incident intensity of UV light (6 µW/cm 2 ). The best rise (t r ) and decay time (t d ) for this photodetector was ∼ 13 ms. Based on the results and the non-toxic/hazardous nature of the substrate, this device shows promising UV photodetection performance under ambient conditions and is found suitable for wearable devices to protect humans from getting exposed to harmful UV radiation.

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QCD topology and axion properties in an isotropic hot and dense medium

arXiv

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arXiv 2024年

作者： Gong, Hong-Fang Lu, Qi Lu, Zhen-Yan Liu, Lu-Meng Chen, Xun Wang, Shu-Peng Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and Electronics Hunan University of Science and Technology Xiangtan411201 China School of Physics Beihang University Beijing102206 China Physics Department Center for Particle Physics and Field Theory Fudan University Shanghai200438 China School of Nuclear Science and Technology University of South China Hengyang421001 China School of Physics and Electronics Hunan University Changsha410082 China

We study the QCD topology and axion properties at finite temperature and chemical potential in the framework of the two-flavor Nambu−Jona-Lasinio model. We find that the behaviors of the two lowest cumulants of the QCD topological charge distribution and axion properties are highly sensitive to the critical behavior of the chiral phase transition. In particular, the topological susceptibility and the axion mass follow the response of the chiral condensate to temperature and chemical potential, showing that both quantities decrease monotonically with the increment of temperature and/or chemical potential. However, it is important to note that the normalized fourth cumulant behaves differently depending on the temperature. At low temperatures, it is a non-monotonic function of the chemical potential, while at high temperatures, it monotonically decreases. Additionally, its value invariably approaches the asymptotic value of binst2 = −1/12, predicted by the dilute instanton gas model. We also observe that with the increase in chemical potential at relatively low temperatures, the axion self-coupling constant exhibits a sharp peak around the critical point, which can even be more than twice its vacuum value. After that, the self-coupling drops sharply to a much lower value than its vacuum value, eventually approaching zero in the high chemical potential limit. The finding that the axion self-coupling constant is significantly enhanced in high-density environments near the chiral phase transition could lead to the creation or enhancement of an axion Bose-Einstein condensate in compact astrophysical objects. Copyright © 2024, The Authors. All rights reserved.

关键词： Topology

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Freely Suspended Platinum Diselenide Membranes without Polymer Support for Piezoresistive Pressure Sensing

Freely Suspended Platinum Diselenide Membranes without Polym...

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Device Research Conference

作者： Sebastian Lukas Vikas Jangra Nico Rademacher Michael Gross Eva Desgué Maximilian Prechtl Oliver Hartwig Cormac Ó Coileáin Tanja Stimpel-Lindner Satender Kataria Pierre Legagneux Georg S. Duesberg Max C. Lemme Chair of Electronic Devices RWTH Aachen University Aachen Germany THALES R&T Palaiseau France Faculty of Electrical Engineering and Information Technology (EIT 2) Center for Integrated Sensor Systems Institute of Physics University of the Bundeswehr Munich Neubiberg Germany AMO GmbH Advanced Microelectronic Center Aachen Aachen Germany

Platinum diselenide (PtSe 2 ) is a layered two-dimensional (2D) material with outstanding electronic and piezoresistive properties [1]–[3] . It has demonstrated its potential for membrane-based pressure sensor devices, where poly(methyl methacrylate) (PMMA) supported and suspended the PtSe2 membranes [4] . The impact of the polymer support layer on the response of the suspended 2D material is still under investigation [5] . To study the strain and the piezoresistive behavior, we fabricated and analyzed devices based on suspended PtSe 2 membranes with and without polymer support.

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Cold quark matter in a quasiparticle model: thermodynamic consistency and stellar properties

arXiv

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arXiv 2023年

作者： Ma, Zhi-Jun Lu, Zhen-Yan Xu, Jian-Feng Peng, Guang-Xiong Fu, Xiangyun Wang, Junnian Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and Electronics Hunan University of Science and Technology Xiangtan411201 China College of Information Engineering Suqian University Suqian223800 China School of Nuclear Science and Technology University of Chinese Academy of Sciences Beijing100049 China Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China

The strong coupling in the effective quark mass was usually taken as a constant in a quasiparticle model while it is, in fact, running with an energy scale. With a running coupling, however, the thermodynamic inconsistency problem appears in the conventional treatment. We show that the renormalization subtraction point should be taken as a function of the summation of the biquadratic chemical potentials if the quark’s current masses vanish, in order to ensure full thermodynamic consistency. Taking the simplest form, we study the properties of up-down (ud) quark matter, and confirm that the revised quasiparticle model fulfills the quantitative criteria for thermodynamic consistency. Moreover, we find that the maximum mass of an ud quark star can be larger than two times the solar mass, reaching up to 2.31M☉, for reasonable model parameters. However, to further satisfy the upper limit of tidal deformability Λ˜1.4 ≤ 580 observed in the event GW170817, the maximum mass of an ud quark star can only be as large as 2.08M☉, namely Mmax . 2.08M☉. In other words, our results indicate that the measured tidal deformability for event GW170817 places an upper bound on the maximum mass of ud quark stars, but which does not rule out the possibility of the existence of quark stars composed of ud quark matter, with a mass of about two times the solar mass. © 2023, CC BY-NC-ND.

关键词： Stars

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Real-Time Bird Counting and Environmental Control System for Enhanced Swiftlet Farmhouse Management

SSRN

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SSRN 2025年

作者： Markom, Arni Munira Rahman, Nuraishah Najiha Abdul Hamdan, Fakhirul Aziff Yusof, Yusrina Haris, Hazlihan Zaini, Muhammad Aizat Zaim Roslizar, Ahmad Muzammil Latiff, Anas Abdul Muhammad, Ahmad Razif Markom, Marni Azira School of Electrical Engineering College of Engineering Universiti Teknologi MARA Selangor Shah Alam40450 Malaysia Sabah Kota Kinabalu88400 Malaysia Hang Tuah Jaya Durian Tunggal Melaka76100 Malaysia Universiti Kebangsaan Malaysia UKM Selangor Bangi43600 Malaysia Faculty of Electronic Engineering & Technology Universiti Malaysia Perlis Kampus Pauh Putra Perlis Arau02600 Malaysia Center of Excellence for Advanced Sensor Technology Universiti Malaysia Perlis Kampus Pauh Putra Perlis Arau02600 Malaysia

This study presents the development of an IoT-based system for environmental monitoring and control, as well as bird counting, specifically designed for swiftlet farming in Menumbok, Sabah. The system integrates DHT11 and ultrasonic sensors to optimize habitat conditions and track swiftlet activity. Swiftlet farms face critical challenges in maintaining optimal environmental parameters and accurately monitoring bird populations, both essential for swiftlet health and productivity. The primary objective of this project is to establish a comprehensive system that not only monitors environmental factors but also allows farmers to actively control them, improving overall farm management. A key feature of this system is the ability to pump water from a barrel to a basin on the floor to regulate humidity levels, thereby enhancing the microenvironment for swiftlets. Two main methodologies were employed: (1) the installation of DHT11 sensors for continuous temperature and humidity measurement, ensuring optimal conditions for swiftlet habitation, and (2) the use of ultrasonic sensors at key entry points to accurately count swiftlets entering and exiting the farmhouse, providing precise data on their activity patterns. Key findings from the study include: (1) an average of approximately 600 swiftlets entered the farmhouse during peak evening hours (6 PM to 8 PM), while around 570 exited in the morning (5 AM to 7 AM), indicating stable population dynamics;(2) environmental data indicated temperature ranges from 31.9°C to 34.6°C, with humidity levels averaging 79%, which, while slightly below the optimal range, can be adjusted using the control system;and (3) variations in swiftlet activity were recorded, particularly increased movement during nighttime, suggesting external environmental influences on their behavior. In conclusion, this research demonstrates the effectiveness of integrating IoT technology for both environmental control and bird monitoring in swiftlet farming, o

关键词： Environmental monitoring

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UAS Simulator: A Laboratory Set-Up 1

UAS Simulator: A Laboratory Set-Up

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1st International Conference on Emerging Trends in Information technology and Engineering, ic-ETITE 2020

作者： Kasana, Abhishek Misra, Ajay Naidu, V.P.S. Defence Institute of Advanced Technology Department of Aerospace Engg. Pune India CSIR - National Aerospace Laboratories Multi-Sensor Data Fusion Lab Bangalore-17 India

ISBN: (纸本)9781728141428

This work describes the procedure for laboratory setup for Unmanned Aerial System (UAS) Simulator. UAS has three major components viz., UAV (or drone), Pilot and the system in place that connects both of them or interface. This simulator not only helps pilot for training purposes, designers for testing new models, mission planners in planning missions in a different environment but also helps in testing and development of the Synthetic Vision System (SVS). SVS generates a rendered image or 3D image of the flying environment and aware operator using an onboard database of terrain, obstacles, and relevant cultural features. © 2020 IEEE.

关键词： Unmanned aerial vehicles (UAV)

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Field enhanced photocatalytic disinfection

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Science Bulletin 2022年第8期67卷 779-783页

作者： Baoying Dai Hongqing Feng Zhou Li Yannan Xie State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Jiangsu Key Laboratory for BiosensorsJiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China

An enormous number and tremendous diversity of microorganisms(such as bacteria and viruses)are surrounding us in our daily life,most of which we can live together in harmony under common circumstance.

关键词：场增强光催化灭菌 of

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