Clutter Interference and the Integration Time of Echoes in the Echolocating Bat, Eptesicus fuscus

1988 ◽  
Author(s):  
James A. Simmons ◽  
Edward G. Freedman ◽  
Scott B. Stevenson ◽  
Lynda Chen ◽  
Timothy J. Wohlgemant
Keyword(s):  
Eptesicus Fuscus ◽  
Integration Time

Clutter interference and the integration time of echoes in the echolocating bat, Eptesicus fuscus

1989 ◽  
Vol 86 (4) ◽  
pp. 1318-1332 ◽  
Author(s):  
James A. Simmons ◽  
Edward G. Freedman ◽  
Scott B. Stevenson ◽  
Lynda Chen ◽  
Timothy J. Wohlgenant
Keyword(s):  
Eptesicus Fuscus ◽  
Integration Time

Symmetric Multistep Methods Revisited: II. Numerical Experiments

1999 ◽  
Vol 173 ◽  
pp. 309-314 ◽  
Author(s):  
T. Fukushima
Keyword(s):  
Multistep Methods ◽  
Computational Time ◽  
Integration Time ◽  
Implicit Methods ◽  
Symmetric Methods ◽  
Celestial Bodies ◽  
The Stability ◽  
Predictor Corrector ◽  
Symmetric Multistep Methods ◽  
Integration Errors

AbstractBy using the stability condition and general formulas developed by Fukushima (1998 = Paper I) we discovered that, just as in the case of the explicit symmetric multistep methods (Quinlan and Tremaine, 1990), when integrating orbital motions of celestial bodies, the implicit symmetric multistep methods used in the predictor-corrector manner lead to integration errors in position which grow linearly with the integration time if the stepsizes adopted are sufficiently small and if the number of corrections is sufficiently large, say two or three. We confirmed also that the symmetric methods (explicit or implicit) would produce the stepsize-dependent instabilities/resonances, which was discovered by A. Toomre in 1991 and confirmed by G.D. Quinlan for some high order explicit methods. Although the implicit methods require twice or more computational time for the same stepsize than the explicit symmetric ones do, they seem to be preferable since they reduce these undesirable features significantly.

Comparative Assessment of Optical Techniques for Semi-Invasive SRAM Data Read-out on an MSP430 Microcontroller

2018 ◽  
Author(s):  
Tuba Kiyan ◽  
Heiko Lohrke ◽  
Christian Boit
Keyword(s):  
Supply Voltage ◽  
Photon Emission ◽  
Random Access ◽  
Integration Time ◽  
Security Evaluation ◽  
Testing And Debugging ◽  
Advantages And Disadvantages ◽  
The Core ◽  
Voltage Signal ◽  
Chip Testing

Abstract This paper compares the three major semi-invasive optical approaches, Photon Emission (PE), Thermal Laser Stimulation (TLS) and Electro-Optical Frequency Mapping (EOFM) for contactless static random access memory (SRAM) content read-out on a commercial microcontroller. Advantages and disadvantages of these techniques are evaluated by applying those techniques on a 1 KB SRAM in an MSP430 microcontroller. It is demonstrated that successful read out depends strongly on the core voltage parameters for each technique. For PE, better SNR and shorter integration time are to be achieved by using the highest nominal core voltage. In TLS measurements, the core voltage needs to be externally applied via a current amplifier with a bias voltage slightly above nominal. EOFM can use nominal core voltages again; however, a modulation needs to be applied. The amplitude of the modulated supply voltage signal has a strong effect on the quality of the signal. Semi-invasive read out of the memory content is necessary in order to remotely understand the organization of memory, which finds applications in hardware and software security evaluation, reverse engineering, defect localization, failure analysis, chip testing and debugging.

The Energy Response of Calorimeters

2018 ◽  
Author(s):  
Richard Wigmans
Keyword(s):  
Sampling Frequency ◽  
Integration Time ◽  
Signal Integration ◽  
Energy Response ◽  
Absorption Process ◽  
Active Materials ◽  
Unit Energy ◽  
Sampling Fraction ◽  
Signal Integration Time ◽  
Calorimeter Response

This chapter deals with the signals produced by particles that are being absorbed in a calorimeter. The calorimeter response is defined as the average signal produced per unit energy deposited in this absorption process, for example in terms of picoCoulombs per GeV. Defined in this way, a linear calorimeter has a constant response. Typically, the response of the calorimeter depends on the type of particle absorbed in it. Also, most calorimeters are non-linear for hadronic shower detection. This is the essence of the so-called non-compensation problem, which has in practice major consequences for the performance of calorimeters. The origins of this problem, and its possible solutions are described. The roles of the sampling fraction, the sampling frequency, the signal integration time and the choice of the absorber and active materials are examined in detail. Important parameters, such as the e/mip and e/h values, are defined and methods to determine their value are described.

scholarly journals Porosity Analysis of Additive Manufactured Parts Using CAQ Technology

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1142
Author(s):  
Peter Pokorný ◽  
Štefan Václav ◽  
Jana Petru ◽  
Michaela Kritikos
Keyword(s):  
Manufacturing Process ◽  
Scanning Speed ◽  
Additive Technologies ◽  
Integration Time ◽  
Detector Resolution ◽  
Porosity Analysis ◽  
3D Scans ◽  
Printing Direction ◽  
Non Destructive

Components produced by additive technology are implemented in various spheres of industry, such as automotive or aerospace. This manufacturing process can lead to making highly optimized parts. There is not enough information about the quality of the parts produced by additive technologies, especially those made from metal powder. The research in this article deals with the porosity of components produced by additive technologies. The components used for the research were manufactured by the selective laser melting (SLM) method. The shape of these components is the same as the shape used for the tensile test. The investigated parts were printed with orientation in two directions, Z and XZ with respect to the machine platform. The printing strategy was “stripe”. The material used for printing of the parts was SS 316L-0407. The printing parameters were laser power of 200 W, scanning speed of 650 mm/s, and the thickness of the layer was 50 µm. A non-destructive method was used for the components’ porosity evaluation. The scanning was performed by CT machine METROTOM 1500. The radiation parameters used for getting 3D scans were voltage 180 kV, current 900 µA, detector resolution 1024 × 1024 px, voxel size 119.43 µm, number of projections 1050, and integration time 2000 ms. This entire measurement process responds to the computer aided quality (CAQ) technology. VG studio MAX 3.0 software was used to evaluate the obtained data. The porosity of the parts with Z and XZ orientation was also evaluated for parts’ thicknesses of 1, 2, and 3 mm, respectively. It has been proven by this experimental investigation that the printing direction of the part in the additive manufacturing process under question affects its porosity.

scholarly journals Liquid-Mirror Telescope Surveys

1998 ◽  
Vol 11 (1) ◽  
pp. 464-467
Author(s):  
P. Hickson
Keyword(s):  
Integration Time ◽  
Spectral Energy ◽  
Energy Distributions ◽  
Ccd Cameras ◽  
Photometric Redshifts ◽  
Rotating Liquid ◽  
Liquid Mirrors ◽  
Under Construction ◽  
Optical Telescopes ◽  
Mirror Telescope

Abstract Recent advances in the technology of rotating liquid-mirrors now make feasible the construction of large optical telescopes for dedicated survey programs. Two three-metre-class astronomical telescopes have been built and asix-metre telescope is under construction. These instruments observe in zenith-pointing mode, using drift-scanning CCD cameras to record continuous imaging of a strip of sky typically 20 arcmin wide. This enables them to observe of order 100 square degrees of sky with an integration time of a few minutes per night. Data can be co-added from night to night in order to increase the depth of the survey. Liquid-mirror telescopes are particularly wellsuited to surveys using broad or intermediate bandwidth filters to obtain photometric redshifts and spectral energy distributions for faint galaxies and quasars.

scholarly journals Daytime perimeter environmental noise in the vicinity of four hospitals in the city of Lima, Peru

Noise Mapping ◽  
2020 ◽  
Vol 7 (1) ◽  
pp. 239-247
Author(s):  
Alberto E. García-Rivero ◽  
Ricardo Ángel Yuli-Posadas ◽  
Warren Reátegui Romero ◽  
Odón Sánchez-Ccoyllo ◽  
Wilfredo Bulege-Gutierrez ◽  
...  
Keyword(s):  
Working Hours ◽  
Environmental Noise ◽  
Integration Time ◽  
Environmental Standards ◽  
Mean Values ◽  
The Hours ◽  
Measurement Mode ◽  
Special Protection Areas ◽  
The City ◽  
National Environmental

AbstractThe present study is intended to get to know the levels of perimeter diurnal environmental noise of four hospitals in the city of Lima. The measurement mode used at each hospital was A-weighting, with an integration time of five minutes per recording. It was measured in the FAST mode with calibrations made at the beginning and end of the measurement day. Statistical analysis consisted of the mean comparison T test which was applied at all the hospitals considered in the study. At the four hospitals, at all the hours of measurement and both on working days and non-working days (Sunday), LAeq mean values are higher than 83 dBA. On working days, two periods of maximum noise from 08:00 to 10:00 in the morning and from 17:00 to 19:00 in the afternoon coincide with the start and end of working hours. The perimeter diurnal environmental noise levels determined at the vicinity of four hospitals show higher values in all cases to those established by the Peruvian National Environmental Standards for Noise for special protection areas both for working days and for non-working days. Noise that comes from the dense and disorganized traffic of Lima plays a fundamental role in this behaviour.

scholarly journals The Influence of an Integration Time Step on Dynamic Calculation of a Vehicle-Track-Bridge under High-Speed Railway

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 431
Author(s):  
Junjie Ye ◽  
Hao Sun
Keyword(s):  
High Speed ◽  
Coupled Model ◽  
Short Wave ◽  
Integration Time ◽  
Vertical Acceleration ◽  
Dynamic Calculation ◽  
Time Step ◽  
High Speed Railway ◽  
Track Irregularity ◽  
Track Bridge

In order to study the influence of an integration time step on dynamic calculation of a vehicle-track-bridge under high-speed railway, a vehicle-track-bridge (VTB) coupled model is established. The influence of the integration time step on calculation accuracy and calculation stability under different speeds or different track regularity states is studied. The influence of the track irregularity on the integration time step is further analyzed by using the spectral characteristic of sensitive wavelength. According to the results, the disparity among the effect of the integration time step on the calculation accuracy of the VTB coupled model at different speeds is very small. Higher speed requires a smaller integration time step to keep the calculation results stable. The effect of the integration time step on the calculation stability of the maximum vertical acceleration of each component at different speeds is somewhat different, and the mechanism of the effect of the integration time step on the calculation stability of the vehicle-track-bridge coupled system is that corresponding displacement at the integration time step is different. The calculation deviation of the maximum vertical acceleration of the car body, wheel-sets and bridge under the track short wave irregularity state are greatly increased compared with that without track irregularity. The maximum vertical acceleration of wheel-sets, rails, track slabs and the bridge under the track short wave irregularity state all show a significant declining trend. The larger the vibration frequency is, the smaller the range of integration time step is for dynamic calculation.

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