Spatial Estimation of Accelerated Stimuli Is Based on a Linear 					Extrapolation of First-Order Information

Abstract. We examined spatial estimation of accelerating objects (−8, −4, 0, +4, or +8 deg/s2) during occlusion (600, 1,000 ms) in a spatial prediction motion task. Multiple logistic regression indicated spatial estimation was influenced by these factors such that participants estimated objects with positive acceleration to reappear behind less often than those with negative acceleration, and particularly after the longer occlusion. Individual-participant logistic regressions indicated spatial estimation was better predicted by a first-order extrapolation of the occluded object motion based on pre-occlusion velocity rather than a second-order extrapolation that took account of object acceleration. We suggest a general principle of extrapolation is involved in prediction motion tasks whereby there is a contraction of the variable of interest (i.e., displacement in spatial prediction motion and time in temporal prediction motion). Such an approach to extrapolation could be advantageous as it would offer participants better opportunity to correct for an initial estimation error.

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Temporal Prediction Errors Affect Short-Term Memory Scanning Response Time

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000339 ◽

2016 ◽

Vol 63 (6) ◽

pp. 333-342

Author(s):

Roberto Limongi ◽

Angélica M. Silva

Keyword(s):

Response Time ◽

Short Term Memory ◽

Estimation Error ◽

Predictive Coding ◽

Time Estimation ◽

Prediction Errors ◽

Memory Scanning ◽

Short Term ◽

Term Memory ◽

Temporal Prediction

Abstract. The Sternberg short-term memory scanning task has been used to unveil cognitive operations involved in time perception. Participants produce time intervals during the task, and the researcher explores how task performance affects interval production – where time estimation error is the dependent variable of interest. The perspective of predictive behavior regards time estimation error as a temporal prediction error (PE), an independent variable that controls cognition, behavior, and learning. Based on this perspective, we investigated whether temporal PEs affect short-term memory scanning. Participants performed temporal predictions while they maintained information in memory. Model inference revealed that PEs affected memory scanning response time independently of the memory-set size effect. We discuss the results within the context of formal and mechanistic models of short-term memory scanning and predictive coding, a Bayes-based theory of brain function. We state the hypothesis that our finding could be associated with weak frontostriatal connections and weak striatal activity.

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Temporal prediction of the arrival point of a moving target

Internal Medicine Review ◽

10.18103/imr.v2i8.145 ◽

2016 ◽

Vol 2 (8) ◽

Author(s):

Ryo Koshizawa

Keyword(s):

Cerebral Cortex ◽

Information Processing ◽

Task Performance ◽

Functional Properties ◽

Visual Information ◽

Moving Target ◽

Font Size ◽

Temporal Prediction ◽

Individual Participant ◽

Arrival Point

Coincidence-anticipation timing (CAT), a form of temporal prediction, is necessary not only in sports, but in many everyday situations. This review summarizes temporal prediction of a moving target at an arrival point in terms of both task performance and the functional properties of the cerebral cortex during CAT. In terms of CAT task performance, temporal accuracy during a CAT task depends on both the specific task conditions, and individual participant characteristics or conditions that might affect information processing in the cerebral cortex. In terms of the functional properties of the cerebral cortex during CAT, as it is possible to continuously gaze at a moving target to a non-occluded arrival point, participants need only to ascertain its velocity, which relies mainly upon the functional properties of the parietal. However, as it is impossible to continuously gaze at the moving target when the arrival point is occluded, participants need to transfer from processing the visual information gained during the visible section of movement to predicting the target’s movement in the occluded section, which relies mainly upon the functional properties of the premotor. In addition, the premotor mainly contribute toward facilitation of information processing by training in the CAT task. Future establishment of a strategy for accurate temporal prediction of moving targets, informed by further studies in CAT tasks, might allow for more accurate temporal prediction to be made, even without formal training.

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Synthesis of cam profile using classical splines and the effect of knot locations on the acceleration, jump, and interface force of cam follower system

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406211405926 ◽

2011 ◽

Vol 225 (12) ◽

pp. 3019-3030 ◽

Cited By ~ 7

Author(s):

U Chavan ◽

S Joshi

Keyword(s):

Displacement Function ◽

Physical Parameters ◽

Spline Curves ◽

Design Variables ◽

Negative Acceleration ◽

Positive Acceleration ◽

Large Jump ◽

Cam Follower ◽

Displacement Profile ◽

Cam Profile

Large positive acceleration against a load creates cam follower interface force that can cause excessive wear. Negative acceleration tends to reduce the cam follower interface force, and if the negative acceleration is sufficiently large, jump between the cam and follower can occur. Hence, these are the two main concerns of cam designers. This study presents a new approach to adjust the acceleration, interface force, and jump in the early phase of cam design. Knot locations of polynomial pieces of spline curves are considered as design variables which gives variety of cam profiles. Here, design process starts from displacement profile and there is no need for predefined acceleration curves. A single dwell cam displacement function is defined by classical spline curve, made up of four polynomial pieces that are tied together at their ends, called knots. Specifications of these knots are considered for synthesis and analysis of cam follower system. Mathematical relation between interface force and knot locations is presented as wear and jump models. These models are useful to reduce wear and jump by proper placement of the knots on the basis of interface force. By dynamic simulation of cam follower system, cam curves are drawn for different cases of knot locations and good resemblance was found with theoretical curves. This study suggests the cam designers have the added option to control the kinematic and dynamic quantities without changing the physical parameters of cam follower system.

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Global and Local Contributions to the Optical Specification of Time to Contact: Observer Sensitivity to Composite Tau

Perception ◽

10.1068/p3230 ◽

2002 ◽

Vol 31 (8) ◽

pp. 901-924 ◽

Cited By ~ 26

Author(s):

Reinoud J Bootsma ◽

Cathy M Craig

Keyword(s):

Discrimination Performance ◽

Forced Choice ◽

Object Motion ◽

Time To Contact ◽

Local Expansion ◽

First Order ◽

Optical Distance ◽

Observer Motion ◽

Environmental Element ◽

Global And Local

First-order time remaining until a moving observer will pass an environmental element is optically specified in two different ways. The specification provided by global tau (based on the pattern of change of angular bearing) requires that the element is stationary and that the direction of motion is accurately detected, whereas the specification provided by composite tau (based on the patterns of change of optical size and optical distance) does not require either of these. We obtained converging evidence for our hypothesis that observers are sensitive to composite tau in four experiments involving relative judgments of time to passage with forced-choice methodology. Discrimination performance was enhanced in the presence of a local expansion component, while being unaffected when the detection of the direction of heading was impaired. Observers relied on the information carried in composite tau rather than on the information carried in its constituent components. Finally, performance was similar under conditions of observer motion and conditions of object motion. Because composite tau specifies first-order time remaining for a large number of situations, the different ways in which it may be detected are discussed.

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Discrete-time sliding mode observer for the state estimation of a manoeuvring target

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651819826488 ◽

2019 ◽

Vol 233 (7) ◽

pp. 847-854

Author(s):

K Harikumar ◽

Titas Bera ◽

Rajarshi Bardhan ◽

Suresh Sundaram

Keyword(s):

Boundary Layer ◽

Discrete Time ◽

Sliding Mode ◽

Estimation Error ◽

Sliding Mode Observer ◽

Unknown Parameters ◽

First Order ◽

Error Dynamics ◽

And Performance ◽

The Stability

This article addresses the problem of estimating the position, velocity, and acceleration of a manoeuvring target from noisy position measurements. A discrete-time sliding mode observer is designed to handle unmeasured disturbance input and measurement noise. A first-order linear dynamics is considered for target acceleration. The acceleration input command and the pole of the first-order acceleration dynamics are considered to be unknown parameters with known upper bounds. A finite non-zero boundary layer is employed to reduce the chattering phenomenon typically associated with sliding mode observers. Analysis of estimation error dynamics is presented for the case where the discrete-time sliding mode observer is operating outside the boundary layer and also within the boundary layer. An algorithm is developed for obtaining the observer gain vector that guarantees the stability of the error dynamics. Numerical simulations and experimental results are presented to validate the stability and performance of the proposed observer.

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Ocular pursuit and the estimation of time-to-contact with accelerating objects in prediction motion are controlled independently based on first-order estimates

Experimental Brain Research ◽

10.1007/s00221-009-2139-0 ◽

2009 ◽

Vol 202 (2) ◽

pp. 327-339 ◽

Cited By ~ 20

Author(s):

Nicolas Benguigui ◽

Simon J. Bennett

Keyword(s):

Time To Contact ◽

Ocular Pursuit ◽

First Order ◽

Prediction Motion ◽

Estimation Of Time

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Optimal Deterministic State Estimation—A First Step

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.3143733 ◽

1984 ◽

Vol 106 (2) ◽

pp. 176-178 ◽

Cited By ~ 3

Author(s):

R. G. Jacquot

Keyword(s):

Objective Function ◽

Linear Time ◽

Estimation Error ◽

Stochastic Estimation ◽

Initial Condition ◽

State Estimator ◽

First Order ◽

Linear Time Invariant ◽

Linear Time Invariant Systems ◽

Time Invariant

Optimal deterministic observers are derived for all first order linear time invariant systems. The optimization process consists of minimizing an objective function which is quadratic in the observer gain and in the estimation error. The objective function was chosen such that the resulting observer gains would be independent of system initial-condition which would, in general, be unknown to the state estimator. The results of this optimization are sensible in the light of the stochastic estimation results of Kalman.

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Numerical investigation of the spatial estimation error in sensor guidance used for the localization of a gaseous source in a 2D domain

2011 19th Mediterranean Conference on Control & Automation (MED) ◽

10.1109/med.2011.5983168 ◽

2011 ◽

Cited By ~ 4

Author(s):

Michael A. Demetriou ◽

Nikolaos A. Gatsonis ◽

Jeffrey R. Court

Keyword(s):

Numerical Investigation ◽

Estimation Error ◽

Spatial Estimation ◽

Gaseous Source

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The Association between Prostate-Specific Antigen Velocity (PSAV), Value and Acceleration, and of the Free PSA/Total PSA Index or Ratio, with Prostate Conditions

Journal of Clinical Medicine ◽

10.3390/jcm9113400 ◽

2020 ◽

Vol 9 (11) ◽

pp. 3400

Author(s):

María-Carmen Flores-Fraile ◽

Bárbara Yolanda Padilla-Fernández ◽

Sebastián Valverde-Martínez ◽

Magaly Marquez-Sanchez ◽

María-Begoña García-Cenador ◽

...

Keyword(s):

Prostate Specific Antigen ◽

De Novo ◽

Specific Antigen ◽

Ratio Method ◽

Normal Prostate ◽

Free Psa ◽

Negative Acceleration ◽

Positive Acceleration ◽

Total Psa ◽

Prostate Health

Introduction: Prostate-specific antigen velocity (PSAV) is used to monitor men with clinical suspicion of prostate cancer (PCa), with a normal cut-off point of 0.3–0.5 ng/mL/year. The aim of the study is to establish the predictive capacity of PSAV (value and acceleration) and of the free PSA/total PSA index or ratio. Method: Prospective multicentre observational study in 2035 men of over 47 years of age. Inclusion criteria: men who wished to be informed on the health of their prostate. Exclusion criteria: men with a previously diagnosed prostate condition. Groups: GA: (n = 518): men with serum PSA equal to or greater than 2.01 ng/mL. GB: (n = 775): men with serum PSA greater than or equal to 0.78 ng/mL and less than 2.01 ng/mL. GC: (n = 742): men with serum PSA less than 0.78 ng/mL. Variables: prostate-specific antigen (PSA); age; body mass index (BMI); PSA velocity (PSAV) (ng/mL per year); free PSA/total PSA index (iPSA); PSAV acceleration (increasing: positive, or decreasing: negative); prostate diagnosis (benign prostatic hyperplasia (BPH), prostatic intraepithelial neoplasia (PIN), or infectious and non-infectious prostatitis and prostatic adenocarcinoma (PCa)); de novo diagnoses of urinary tract diseases or conditions; concomitant treatments, diseases and conditions; final diagnosis of prostate health. Results: Mean age 62.35 years (SD 8.12), median 61 (47–94); age was lowest in GC. Mean BMI was 27.89 kg/m2 (SD 3.96), median 27.58 (18.56–57.13); no differences between groups. Mean PSAV was 0.69, SD 2.16, median 0.13 (0.001–34.46); PSAV was lowest in GC. Mean iPSA was 27.39 u/L (SD 14.25), median 24.29 (3.7–115); iPSA was lowest in GA. PSAV had more positive acceleration in GA and more negative acceleration in GC. There were 1600 (78.62%) cases of normal prostate or BPH, 322 (15.82%) cases of PIN or non-infectious prostatitis, and 113 (5.55%) cases of PCa. There were more cases of BPH in GC and more cases of PIN or prostatitis and cancer in GA (p = 0.00001). De novo diagnoses: 15 cases of urinary incontinence (UI), 16 discomfort/pain in LUT, 112 cases of voiding disorders, 12 urethral strictures, 19 hematuria, 51 cystitis, 3 pyelonephritis, 4 pelvic inflammatory disease; no differences were found between groups. In the multivariate analysis, PSAV and the direction of PSAV acceleration (positive or negative) were the variables which were correlated most strongly with prostate health. iPSA was associated with the presence of prostatitis, PCa, and BPH. Men in GA had more prostatitis, PCa, treatment with alpha blockers, and history of previous smoking. GB had more cases of BPH and more positive acceleration of PSAV. GC had more normal prostates, more BPH, more use of ranitidine, and more PSAV with negative acceleration. Conclusions: PSAV, direction of PSAV acceleration, and iPSA in PSA cut-off points of 0.78 ng/mL and 2.01 ng/mL in a priori healthy men over 47 predict the probability of benign or malignant pathology of the prostate.

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Is Acceleration Used for Ocular Pursuit and Spatial Estimation during Prediction Motion?

PLoS ONE ◽

10.1371/journal.pone.0063382 ◽

2013 ◽

Vol 8 (5) ◽

pp. e63382 ◽

Cited By ~ 16

Author(s):

Simon J. Bennett ◽

Nicolas Benguigui

Keyword(s):

Ocular Pursuit ◽

Spatial Estimation ◽

Prediction Motion

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