修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

过滤筛选

出版时间
  • 2018
研究主题
  • Plastic rod scintillator
  • Radiation interaction position
  • Artificial Neural Network
  • Position sensitive detector
应用领域
  • Optoelectronic Information Science and Engineering
机构单位
  • University of Qom
  • Shahrood University of Technology
109 条数据
?? 中文（中国） ▾

  • Estimation of Intraocular Lens Power Calculation after Myopic Corneal Refractive Surgery: Using Corneal Height in Anterior Segment Optical Coherence Tomography

    摘要： Purpose: To investigate the feasibility of estimating effective lens position (ELP) and calculating intraocular lens power using corneal height (CH), as measured using anterior segment optical coherence tomography (AS-OCT), in patients who have undergone corneal refractive surgery. Methods: This study included 23 patients (30 eyes) who have undergone myopic corneal refractive surgery and subsequent successful cataract surgery. The CH was measured with AS-OCT, and the measured ELP (ELPm) was calculated. Intraocular lens power, which could achieve actual emmetropia (Preal), was determined with medical records. Estimated ELP (ELPest) was back-calculated using Preal, axial length, and keratometric value through the SRK/T formula. After searching the best-fit regression formula between ELPm and ELPest, converted ELP and intraocular lens power (ELPconv, Pconv) were obtained and then compared to ELPest and Preal, respectively. The proportion of eyes within a defined error was investigated. Results: Mean CH, ELPest, and ELPm were 3.71 ± 0.23, 7.74 ± 1.09, 5.78 ± 0.26 mm, respectively. The ELPm and ELPest were linearly correlated (ELPest = 1.841 × ELPm – 2.018, p = 0.023, R = 0.410) and ELPconv and Pconv agreed well with ELPest and Preal, respectively. Eyes within ±0.5, ±1.0, ±1.5, and ±2.0 diopters of the calculated Pconv, were 23.3%, 66.6%, 83.3%, and 100.0%, respectively. Conclusions: Intraocular lens power calculation using CH measured with AS-OCT shows comparable accuracy to several conventional methods in eyes following corneal refractive surgery.

    关键词： Intraocular lens power calculation,Corneal height,Corneal refractive surgery,Effective lens position,Anterior segment optical coherence tomography

    更新于2025-09-23 15:22:29

  • The CMS Beam Halo Monitor electronics

    摘要： The CMS Beam Halo Monitor has been successfully installed in the CMS cavern in LHC Long Shutdown 1 for measuring the machine induced background for LHC Run II. The system is based on 40 detector units composed of synthetic quartz Cherenkov radiators coupled to fast photomultiplier tubes (PMTs). The readout electronics chain uses many components developed for the Phase 1 upgrade to the CMS Hadronic Calorimeter electronics, with dedicated firmware and readout adapted to the beam monitoring requirements. The PMT signal is digitized by a charge integrating ASIC (QIE10), providing both the signal rise time, with few nanosecond resolution, and the charge integrated over one bunch crossing. The backend electronics uses microTCA technology and receives data via a high-speed 5 Gbps asynchronous link. It records histograms with sub-bunch crossing timing resolution and is read out via IPbus using the newly designed CMS data acquisition for non-event based data. The data is processed in real time and published to CMS and the LHC, providing online feedback on the beam quality. A dedicated calibration monitoring system has been designed to generate short triggered pulses of light to monitor the efficiency of the system. The electronics has been in operation since the first LHC beams of Run II and has served as the first demonstration of the new QIE10, Microsemi Igloo2 FPGA and high-speed 5 Gbps link with LHC data.

    关键词： Cherenkov and transition radiation,Front-end electronics for detector readout,Beam-line instrumentation (beam position and profile monitors; beam-intensity monitors; bunch length monitors)

    更新于2025-09-23 15:22:29

  • A Large Range of Motion 3D MEMS Scanner With Five Degrees of Freedom

    摘要： Here, we discuss a novel, mixed mode 3D XYZ scanner built within a single foundry process. The device has a large range of motion in X, Y, and Z (14.1 μm in X and Y and 97.9 μm in Z) and can also rotate about two axes (7.4°), making it a 5 degree of freedom scanner. Vertical actuation can be accomplished with both thermal actuators, which have a larger range of motion, and capacitive actuators, which are faster, responding fully up to 3.2 kHz. Although useful for many applications, including scanning probe microscopy, micrometer scale optical microscopy, and manipulation of biological objects, the device was designed to be a 3D scanner for spray-painting atoms upon a surface with nanoscale precision and resolution for nanofabrication. Demonstrating the ability to combine the device with other complicated MEMS systems, it is integrated with an XY scanner designed to serve as a shutter of atomic flux. The full system has 7 degrees of freedom and 12 actuation motors, and because it is built in a low cost commercial foundry with a robust and stable process, it is easy and inexpensive to fabricate multiple copies or integrate into other complicated systems, making a system of systems.

    关键词： electrostatic actuators,thermal actuators,Comb drive,nanopositioning,position control,MEMS

    更新于2025-09-23 15:22:29

  • [IEEE 2018 41st International Conference on Telecommunications and Signal Processing (TSP) - Athens, Greece (2018.7.4-2018.7.6)] 2018 41st International Conference on Telecommunications and Signal Processing (TSP) - Measurement of Relative Position of Camera and Optical Beacon by Simultaneous Passive Method

    摘要： The paper deals with a problem of a passive measurement of the relative position of an optical beacon and an optical camera by a simultaneous analytical method. The beacon is composed of nine light sources which are arranged in space in a defined way. The proposed beacon layout enables the measurement of the beacon range and one position angle of the camera. This paper presents the mathematical model of the measurement method and the results, which were gathered on the basis of the experimental measurements. The standard commercial camera and lenses with four different focal lengths were used.

    关键词： simultaneous passive method,optical camera,optical beacon,measurement,lens focal length,relative position

    更新于2025-09-23 15:22:29

  • [IEEE 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - Saint-Petersburg, Russia (2018.11.26-2018.11.30)] 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) - The Problem of Determination of Coordinates of Unmanned Aerial Vehicles Using a Two-Position System Ground Radar

    摘要： the features of modern methods for detecting and determining the coordinates of small unmanned aerial vehicles using a two-position ground radar system are considered. It is proposed to use the methods developed for multi-sensor radar systems. The limitations and advantages of the two-position radar system are shown. The main potential characteristics of the system and the corresponding restrictions on the conditions of its effective application are determined. Potential characteristics are obtained by simulation methods using mathematical models built on the basis of experimental data.

    关键词： two-position system,radar system,detection of objects,trajectory coordinates,unmanned aerial vehicle,determination of coordinates,air object,joint information processing

    更新于2025-09-23 15:22:29

  • [IEEE 2018 Digital Image Computing: Techniques and Applications (DICTA) - Canberra, Australia (2018.12.10-2018.12.13)] 2018 Digital Image Computing: Techniques and Applications (DICTA) - Inter-Subject Image Registration of Clinical Neck MRI Volumes using Discrete Periodic Spline Wavelet and Free form Deformation

    摘要： This paper presents a framework for inter-patient image registration which uses a multi-thresholds, multi-similarity measures and multi-transformations based on compactly supported spline and discrete periodic spline wavelets (DPSWs) using the Gauss-Newton gradient descent (GNGD) and gradient descent (GD) optimization methods. Our primary intellectual contribution is incorporating DPSWs in the transformation while another includes fusing out-of-range concept in a surface matching technique which is implemented by a multi-transformations and multi-similarity measures. In particular, as a true deformation cannot be achieved by single combination of transformation, similarity measure (SM) and optimization of a registration process, a moving image is required to be brought within the range of a registration. On the other hand, the surface matching technique involves an edge position difference (EPD) SM in which coarse to fine surfaces are matched using multiple thresholds with a spline-based free from deformation (FFD) method. The registration experiments were performed on 3D clinical neck magnetic resonance (MR) images, with the results showing that our proposed method provides good accuracy and robustness.

    关键词： Image registration,edge position difference,multi-resolution,inter-subject registration,optimization,discrete periodic spline wavelet

    更新于2025-09-23 15:22:29

  • [IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - The Wideband Pulsed Antenna and its Application

    摘要： This paper presents a design of the antenna with an expandable slot for effective radiating and receiving the ultra-wideband (UWB), short-pulse (SP) signals. The offered design of the antenna allows creating an interferential electromagnetic field of a bipolar pulse in an equivalent general antenna aperture. A quantitative and quality is evaluation of efficiency of proposed antenna design performed. It is shown that an application of the given antenna allows increasing the damaging range from acting the pulsed UWB signals.

    关键词： temporal position-pulse transmission,wireless system,electromagnetic compatibility,wideband pulsed antenna,ultrawideband signal,data modulation

    更新于2025-09-23 15:21:21

  • Use of YAP(Ce) in the development of high spatial resolution radiation imaging detectors

    摘要： A scintillator with a high light output is considered to be required for the development of high spatial resolution radiation imaging detectors. In contrast to this scientific consensus, we found that high spatial resolution images can be obtained using a medium light output scintillator comprising cerium-doped yttrium aluminum perovskite, YA1O3 (YAP(Ce)). We evaluated the performance of a radiation imaging detector comprising a 0.5 mm thick YAP(Ce) plate, which was optically coupled to a 25.4 mm (1-inch) square position-sensitive photomultiplier. The Anger principle was used to calculate the radiation positions. The spatial resolution and energy resolution for the imaging detector with 5.5 MeV alpha particles were 0.2 mm full width at half-maximum (FWHM) and 7.4% FWHM, respectively. The spatial resolutions for 60 keV gamma photons and ~32 keV X-rays were ~ 0.6 mm FWHM and ~ 0.8 mm FWHM, respectively. The spatial resolution of the detector when imaging beta particles at a maximum energy of 254 keV was less than 0.6 mm FWHM. We conclude that YAP(Ce) is a promising scintillator for developing high spatial resolution and high energy resolution radiation detectors for imaging alpha particles, beta particles, and gamma photons.

    关键词： YAP(Ce),energy resolution,position-sensitive photomultiplier,spatial resolution

    更新于2025-09-23 15:21:21

  • Outage and BER performances of indoor relay-assisted hybrid RF/VLC systems

    摘要： In this study, the authors analyse the outage performance of the indoor relay-assisted hybrid radio frequency (RF)/visible light communication (VLC) systems. They derive closed-form expressions for the outage probability of the end-to-end signal-to-noise ratio. Then they obtain the optimal approximation parameter with optimising the outage probability using the differential evolution algorithm. Moreover, they analysed the average bit error rate (BER) performance of the hybrid RF/optical system using pulse position modulation method while assuming the timing error in synchronisation. Finally, they present some numerical results utilising the newly derived exact closed-form expressions.

    关键词： pulse position modulation,hybrid RF/VLC,BER,differential evolution algorithm,relay-assisted,outage probability

    更新于2025-09-23 15:21:21

  • [IEEE 2019 IEEE 13th International Conference on ASIC (ASICON) - Chongqing, China (2019.10.29-2019.11.1)] 2019 IEEE 13th International Conference on ASIC (ASICON) - Design of the admittance detecting circuit for silicon waveguides using the capacitor-integration method

    摘要： The in?uences of the intermediate band (IB) ?lling, the absorption coef?cient constants, and the IB position on the ef?ciency of a quantum dot intermediate band solar cell (QD-IBSC) are investigated considering the spatial variation of subbandgap generation rates. A new de?nition of optimal intermediate band ?lling is proposed. A mathematical model is developed to optimize the intermediate band solar cell (IBSC) structure under idealized conditions, which calculates the optimal ratio of the subbandgap absorption coef?cient constants and the optimal position of IB.

    关键词： optimal ?lling,Intermediate band solar cell (IBSC),absorption coef?cients,IB position,conversion ef?ciency

    更新于2025-09-23 15:21:01