measuring frequency
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2021 ◽  
Vol 67 (4) ◽  
pp. 37-41
Author(s):  
Simon Koblar

Public transport plays a major role in sustainable mobility planning. This is even more obvious on regional level, where distances are often too long for cycling, therefore public transport remains only viable sustainable travel mode. In the process of preparation of regional SUMP, evaluation of accessibility is one of crucial steps. However, accessibility measurement can be a challenging task. In Slovenia, there have been several studies measuring frequency and access to closest stop, ignoring travel speed and destinations that could be reached. However rapid increase in computing power, software development and availability of schedule data in GTFS format, opened an opportunity to evaluate accessibility more precisely. We performed an analysis for Koroška region in Slovenia. Accessibility was measured with OpenTripPlanner with OpenStreetMap data for road network and schedules in GTFS format. Travel times were measured in both directions for all inhabited cells in a grid resolution of one hectare and central settlements of intermunicipal importance. The results of the analysis are important in terms of understanding how many citizens can access settlements of intermunicipal importance with public transport. This will serve as a baseline measure in regional SUMP preparation and will enable future iterations and comparisons. It also enables us to see the gaps in public transport supply and propose improvements. Open-source tools and open data enables this method to be used in other regions as well.


2021 ◽  
Vol 67 (4) ◽  
pp. 37-41
Author(s):  
Simon Koblar

Public transport plays a major role in sustainable mobility planning. This is even more obvious on regional level, where distances are often too long for cycling, therefore public transport remains only viable sustainable travel mode. In the process of preparation of regional SUMP, evaluation of accessibility is one of crucial steps. However, accessibility measurement can be a challenging task. In Slovenia, there have been several studies measuring frequency and access to closest stop, ignoring travel speed and destinations that could be reached. However rapid increase in computing power, software development and availability of schedule data in GTFS format, opened an opportunity to evaluate accessibility more precisely. We performed an analysis for Koroška region in Slovenia. Accessibility was measured with OpenTripPlanner with OpenStreetMap data for road network and schedules in GTFS format. Travel times were measured in both directions for all inhabited cells in a grid resolution of one hectare and central settlements of intermunicipal importance. The results of the analysis are important in terms of understanding how many citizens can access settlements of intermunicipal importance with public transport. This will serve as a baseline measure in regional SUMP preparation and will enable future iterations and comparisons. It also enables us to see the gaps in public transport supply and propose improvements. Open-source tools and open data enables this method to be used in other regions as well.


2021 ◽  
Author(s):  
Jixin Chen

<div> <p>Here an analytical solution of Fick’s 2<sup>nd</sup> law is used to predict the diffusion and the stochastic adsorption of single diluted solute molecules on flat and patterned surfaces. The equations are then compared to the results of several numerical Monte Carlo simulations using a random walk model. The 1D diffusion simulations clarify that the dependence of the solute-surface collision rate on the observation-time (measurement time resolution) is because of the multiple collisions of the same molecules over different time regions. It also surprisingly suggests that due to the self-mimetic fractal function of diffusion, the equation should be corrected by a factor of two. The absorption rate of solute on an adsorptive surface is found to follow a power-law decay function due to an evolving concentration gradient near the surface along with the depletion of the bulk solute molecules on the surface, for example, in a self-assembled monolayer adsorption kinetics. Thus, the analytical equations developed to calculate the collision at a fixed measuring frequency can be extended to map the whole curve over time. In the last section of this work, 3D diffusion simulations suggest that the analytical solution is valid to predict the adsorption rate of the bulk solute to a small group of adsorptive target molecules/area on a bouncing surface, which is a critical process in analyzing the kinetics of many bio-sensing platforms.</p> </div>


2021 ◽  
Vol 2086 (1) ◽  
pp. 012071
Author(s):  
M A Vodopyanov ◽  
K A Menzorov ◽  
V V Davydov ◽  
V Yu Rud

Abstract The principle of operation of the device for measuring frequency characteristics is considered. Block diagram of a device for measuring the frequency characteristics of a digital frequency comparator with correlation quadrature processing and description of their components is illustrated. The block diagram of the frequency multiplier is given. The accuracy characteristics of the developed meter design are evaluated. They are compared with the characteristics of previously used devices. The Improve accuracy characteristics and increased stability of operation were found.


2021 ◽  
Author(s):  
Christoph Wagner ◽  
Petr Schaffer ◽  
Pouriya Amini Digehsara ◽  
Michael Bärhold ◽  
Dirk Plettemeier ◽  
...  

Abstract Recovering speech in the absence of the acoustic speech signal itself, i.e., silent speech, holds great potential for restoring or enhancing oral communication in those who lost it. Radar is a relatively unexplored silent speech sensing modality, even though it has the advantage of being fully non-invasive. We therefore built a custom stepped frequency continuous wave radar hardware to measure the changes in the transmission spectra during speech between three antennas, located on both cheeks and the chin with a measuring frequency of 100 Hz. We then recorded a command word corpus of 40 phonetically balanced, two-syllable German words and the German digits zero to nine for two individual speakers and evaluated both the speaker-dependent multi-session and inter-session recognition accuracies on this 50-word corpus using a bidirectional long-short term memory network. We obtained recognition accuracies of 99.17 % and 88.87 % for the speaker-dependent multi-session and inter-session accuracy, respectively. These results show that the transmission spectra are very well suited to discriminate individual words from one another, even across different sessions, which is one of the key challenges for fully non-invasive silent speech interfaces.


2021 ◽  
Vol 310 ◽  
pp. 108624
Author(s):  
C. Lammirato ◽  
M. Wallman ◽  
P. Weslien ◽  
L. Klemedtsson ◽  
T. Ruetting

2021 ◽  
Vol 11 (21) ◽  
pp. 9916
Author(s):  
Zhong-Xiang Li ◽  
Chun Hu ◽  
Ming-Zhe Han ◽  
Shang-Chun Fan ◽  
De-Zhi Zheng

Nonlinear interference components exist in the output signals of dual-tube Coriolis mass flowmeters (CMFs) which affect the sensitivity and accuracy of the devices. This nonlinearity still appears under zero flow, which is manifested when the output signal contains a frequency doubling signal. This study (1) investigated an additional-mass method to suppress the nonlinear frequency doubling phenomenon, (2) established a coupling system vibration model with additional mass, built a dynamic differential equation for the vibration of the double-beam coupling system from the Lagrange equation, (3) obtained amplitude frequency information using a fourth-order Runge–Kutta method, (4) determined the suppression effect of the additional mass on the nonlinear frequency doubling phenomenon, and (5) experimentally verified the CMF. The results showed that the base coupled the vibrations of two beams, and the symmetric additional mass suppressed the nonlinear frequency doubling phenomenon, thus suppressing low or high frequencies. Also, the effect of pipeline defects simulated under asymmetric additional mass was obtained through numerical analysis and experimental data. Flowmeters with a required measuring frequency range had the optimal suppression effect on nonlinear frequency doubling and provided theoretical guidance for the nondestructive testing of measuring tubes.


2021 ◽  
Author(s):  
Prasanna V. Kothalkar ◽  
Sathvik Datla ◽  
Satwik Dutta ◽  
John H. L. Hansen ◽  
Yagmur Seven ◽  
...  

2021 ◽  
Vol 1 (8) ◽  
Author(s):  
Yoga Dwi Cahyono ◽  
Samsul Hidayat ◽  
Nugroho Adi Pramono

Icing is one of the main dangers for the flight and are cumulative. The icing is a process of accumulation of ice on parts of the aircraft, which will lead to changes in geometry and resulted in a variety of other disorders. For example, there was a buildup of ice on the propellor (propeller) and the engine carburetor so it can reduce the thrust plane even caused the plane to fall freely (stall). For it needs to be designed and built the Icing Detector as well as the actuator in providing early warning of the existence of the calculation and the icing on the pilot. This instrument is designed with electronic units that use the oscillator as frequency generator and frequency meter based mikrokontroller ATmega8 as the measuring frequency. The surface of the sensor is made up of printed inductor with a broad surface for detection area. Sensors and electronic units connected by cable. In addition, modeling for the pilot indicators have been designed using the LCD. Research results suggest that testing on "Ice Accretion-Level Measurement On Modelling using printed Inductor Sensor Prototype Based On Frequency Shifting" has been a successful made in accordance with the expected functions. These instruments can detect the occurrence of icing and give an indication of the thickness of the ice. It is possible to form a flat sensor installation on the aircraft to be more unobtrusive air flow, as well as a spacious surface produces more accurate results.


Actuators ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 211
Author(s):  
Daniele Leonardis ◽  
Luca Tiseni ◽  
Domenico Chiaradia ◽  
Antonio Frisoli

Wearable haptic devices in the shape of actuated thimbles are used to render the sense of touch in teleoperation and virtual reality scenarios. The design of similar devices has to comply with concurring requirements and constraints: lightweight and compactness, intensity and bandwidth of the rendered signals. Micro-sized motors require a mechanical reduction to increase the output force, at the cost of noise and vibrations introduced by conventional gear reducers. Here we propose a different actuation method, based on a miniaturized twisted string actuator and a flexure hinge transmission mechanism. The latter is required to transmit and transform the pulling force of the twist actuator to a pushing force of the plate in contact with the fingerpad. It achieves a lightweight and noiseless actuation in a compact mechanism. In this work, we present design guidelines of the proposed approach, optimization, and FEM analysis of the flexure hinge mechanism, implementation of the prototype, and experimental characterization of the twist actuator measuring frequency response and output force capabilities.


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