Abnormal Traffic Events Detection Based on Short-time Constant Velocity Model and Spatio-Temporal Trajectory Analysis

In Brazil, malaria caused by Plasmodium vivax presents control challenges due to several reasons, among them the increasing possibility of failure of P. vivax treatment due to chloroquine-resistance (CQR). Despite limited reports of CQR, more extensive studies on the actual magnitude of resistance are still needed. Short-time recurrences of malaria cases were analyzed in different transmission scenarios over three years (2005, 2010, and 2015), selected according to malaria incidence. Multilevel models (binomial) were used to evaluate association of short-time recurrences with variables such as age. The zero-inflated Poisson scan model (scanZIP) was used to detect spatial clusters of recurrences up to 28 days. Recurrences compose less than 5% of overall infection, being more frequent in the age group under four years. Recurrences slightly increased incidence. No fixed clusters were detected throughout the period, although there are clustering sites, spatially varying over the years. This is the most extensive analysis of short-time recurrences worldwide which addresses the occurrence of P. vivax CQR. As an important step forward in malaria elimination, policymakers should focus their efforts on young children, with an eventual shift in the first line of malaria treatment to P. vivax.

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A novel social distancing analysis in urban public space: A new online spatio-temporal trajectory approach

Sustainable Cities and Society ◽

10.1016/j.scs.2021.102765 ◽

2021 ◽

Vol 68 ◽

pp. 102765

Author(s):

Jie Su ◽

Xiaohai He ◽

Linbo Qing ◽

Tong Niu ◽

Yongqiang Cheng ◽

...

Keyword(s):

Public Space ◽

Urban Public Space ◽

Social Distancing ◽

Trajectory Approach ◽

Spatio Temporal ◽

Temporal Trajectory

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Identification of Static Unbalance Wheel of Passenger Car Carried out on a Road

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.214.48 ◽

2014 ◽

Vol 214 ◽

pp. 48-57 ◽

Cited By ~ 3

Author(s):

Krzysztof Prażnowski ◽

Sebastian Brol ◽

Andrzej Augustynowicz

Keyword(s):

Fourier Transform ◽

Wavelet Transform ◽

Constant Velocity ◽

Fourier Transforms ◽

Static Condition ◽

Rotational Frequency ◽

Acceleration Sensor ◽

Short Time Fourier Transform ◽

Road Roughness ◽

Short Time

This paper presents a method of identification of non-homogeneity or static unbalance of the structure of a car wheel based on a simple road test. In particular a method the detection of single wheel unbalance is proposed which applies an acceleration sensor fixed on windscreen. It measures accelerations cause by wheel unbalance among other parameters. The location of the sensor is convenient for handling an autonomous device used for diagnostic purposes. Unfortunately, its mounting point is located away from wheels. Moreover, the unbalance forces created by wheels spin are dumped by suspension elements as well as the chassis itself. It indicates that unbalance acceleration will be weak in comparison to other signals coming from engine vibrations, road roughness and environmental effects. Therefore, the static unbalance detection in the standard way is considered problematic and difficult. The goal of the undertaken research is to select appropriate transformations and procedures in order to determine wheel unbalance in these conditions. In this investigation regular and short time Fourier transform were used as well as wavelet transform. It was found that the use of Fourier transforms is appropriate for static condition (constant velocity) but the results proves that the wavelet transform is more suitable for diagnostic purposes because of its ability of producing clearer output even if car is in the state of acceleration or deceleration. Moreover it was proved that in the acceleration spectrum of acceleration measured on the windscreen a significant peak can be found when car runs with an unbalanced wheel. Moreover its frequency depends on wheel rotational frequency. For that reason the diagnostic of single wheel unbalance can be made by applying this method.

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Marchenko multiple elimination and full wavefield migration in a resonant pinch-out model

Geophysics ◽

10.1190/geo2020-0867.1 ◽

2021 ◽

pp. 1-59

Author(s):

Evert Slob ◽

Lele Zhang ◽

Eric Verschuur

Keyword(s):

Constant Velocity ◽

Local Minimum ◽

Velocity Model ◽

Dominant Frequency ◽

Data Sampling ◽

Multiple Reflections ◽

Linear Inversion ◽

Acoustic Reflection ◽

Reflection Data ◽

Multiple Elimination

Marchenko multiple elimination schemes are able to attenuate all internal multiple reflections in acoustic reflection data. These can be implemented with and without compensation for two-way transmission effects in the resulting primary reflection dataset. The methods are fully automated and run without human intervention, but require the data to be properly sampled and pre-processed. Even when several primary reflections are invisible in the data because they are masked by overlapping primaries, such as in the resonant wedge model, all missing primary reflections are restored and recovered with the proper amplitudes. Investigating the amplitudes in the primary reflections after multiple elimination with and without compensation for transmission effects shows that transmission effects are properly accounted for in a constant velocity model. When the layer thickness is one quarter of the wavelength at the dominant frequency of the source wavelet, the methods cease to work properly. Full wavefield migration relies on a velocity model and runs a non-linear inversion to obtain a reflectivity model which results in the migration image. The primary reflections that are masked by interference with multiples in the resonant wedge model, are not recovered. In this case, minimizing the data misfit function leads to the incorrect reflector model even though the data fit is optimal. This method has much lower demands on data sampling than the multiple elimination schemes, but is prone to get stuck in a local minimum even when the correct velocity model is available. A hybrid method that exploits the strengths of each of these methods could be worth investigating.

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A sensory integration account for time perception

10.1101/2020.08.02.232801 ◽

2020 ◽

Author(s):

Alessandro Toso ◽

Arash Fassihi ◽

Luciano Paz ◽

Francesca Pulecchi ◽

Mathew E. Diamond

Keyword(s):

Time Perception ◽

Time Constant ◽

Sensory Integration ◽

Neuronal Firing ◽

Elapsed Time ◽

Leaky Integrator ◽

Long Time ◽

Integrator Model ◽

Short Time ◽

Sense Of Touch

ABSTRACTThe connection between stimulus perception and time perception remains unknown. The present study combines human and rat psychophysics with sensory cortical neuronal firing to construct a computational model for the percept of elapsed time embedded within sense of touch. When subjects judged the duration of a vibration applied to the fingertip (human) or whiskers (rat), increasing stimulus mean speed led to increasing perceived duration. Symmetrically, increasing vibration duration led to increasing perceived intensity. We modeled spike trains from vibrissal somatosensory cortex as input to dual leaky integrators – an intensity integrator with short time constant and a duration integrator with long time constant – generating neurometric functions that replicated the actual psychophysical functions of rats. Returning to human psychophysics, we then confirmed specific predictions of the dual leaky integrator model. This study offers a framework, based on sensory coding and subsequent accumulation of sensory drive, to account for how a feeling of the passage of time accompanies the tactile sensory experience.

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346. Measurements of the rate of change of temperature in high temperature-short time pasteurization plant

Journal of Dairy Research ◽

10.1017/s0022029900004891 ◽

1947 ◽

Vol 15 (1-2) ◽

pp. 18-23

Author(s):

F. Steghart

Keyword(s):

High Temperature ◽

Time Constant ◽

Rate Of Change ◽

Hot Water ◽

Water Pipe ◽

Temperature Changes ◽

Rates Of Change ◽

High Temperature Short Time ◽

Short Time

It has recently been claimed that in modern high temperature-short time pasteurization plant fluctuations in temperature of the order of 1° F./sec. are unusual and probably artefacts, and that an instantaneous drop is certainly fictitious.It has, nevertheless, been shown that such rapid drops in temperature do in fact occur frequently in high temperature-short time plants of the type investigated. The plant investigated was not of the latest design incorporating devices for speeding up the control by injecting steam directly into the hot-water pipe.Temperature changes of the order of those in question were first observed by Mattick & Hiscox(1) of the National Institute for Research in Dairying, who carried out tests on pasteurization plant using a small mirror galvanometer with a very short time constant. The maximum rates of change were, however, not observed.

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