Temporal Properties of Apparent Motion in Subjective Figures

Perception ◽  
1988 ◽  
Vol 17 (6) ◽  
pp. 729-736 ◽  
Author(s):  
George Mather
Keyword(s):  
Apparent Motion ◽  
Motion Detection ◽  
Time Interval ◽  
Temporal Properties ◽  
Motion Process ◽  
Motion Percept ◽  
High Level ◽  
Level Process

In ‘Kanizsa’ figures, vivid subjective shapes are seen in the absence of explicit contours to define them. When two or more such figures are presented sequentially, so that the subjective shape occupies different positions, good apparent motion of the shape is usually reported. This motion percept must be mediated by a high-level process, in which form extraction precedes motion detection. Some spatial and temporal properties of this motion process are investigated. A major finding is that motion is only perceived when the time interval between successive frames falls below about 500 ms, and the duration of each frame exceeds about 80 ms.

Temporal Properties of the Short-Range Process in Apparent Motion

Perception ◽  
1985 ◽  
Vol 14 (2) ◽  
pp. 181-192 ◽  
Author(s):  
Curtis L Baker ◽  
Oliver J Braddick
Keyword(s):  
Motion Perception ◽  
Apparent Motion ◽  
Motion Detection ◽  
Interstimulus Interval ◽  
Short Range ◽  
Time Interval ◽  
Optimal Motion ◽  
Temporal Properties ◽  
Range Process

A study is reported of the perception of random-dot two-frame apparent motion in which the durations of each exposure and the interstimulus interval between them were varied. The results are largely consistent with the rule that, for optimal motion detection, a portion of each exposure must fall within the same time interval of about 40 ms. In addition, motion perception is separably dependent on the displacement from one exposure to the next and on the time interval between those exposures, rather than on the ‘velocity implied by their ratio.

scholarly journals Are there separate ON and OFF channels in fly motion vision?

1992 ◽  
Vol 8 (2) ◽  
pp. 151-164 ◽  
Author(s):  
Martin Egelhaaf ◽  
Alexander Borst
Keyword(s):  
Visual Field ◽  
Apparent Motion ◽  
Motion Detection ◽  
Visual Information ◽  
Detection System ◽  
Time Interval ◽  
Motion Vision ◽  
Response Component ◽  
Retinal Input ◽  
Motion Detection System

AbstractVisual information is processed in a series of subsequent steps. The performance of each of these steps depends not only on the computations it performs itself but also on the representation of the visual surround on which it operates. Here we investigate the consequences of signal preprocessing for the performance of the motion-detection system of the fly. In particular, we analyze whether the retinal input signals are rectified and segregate into separate ON and OFF channels, which then feed independent parallel motion-detection pathways. We recorded the activity of an identified directionally selective interneuron (HI-cell) in response to apparent motion stimuli, i.e. sequential brightness changes at two neighboring locations in the visual field, as well as to brightness changes at only a single location. For apparent motion stimuli, the motion-dependent response component was determined by subtracting from the overall response the responses to the individual stimulus components when presented alone. The following conclusions could be derived: (1) Apparent motion consisting of a sequence of increased or decreased brightness at two locations in the visual field have the same optimum interstimulus time interval (Fig. 3). (2) Sequences of brightness steps of like polarity (either increments or decrements) elicit positive and negative motion-dependent response components when mimicking motion in the cell's preferred and null direction, respectively. The motion-dependent response components are inverted in sign when the brightness steps of a stimulus sequence have a different polarity (Fig. 7). (3) The responses to the beginning and the end of a brightness pulse depend on the pulse duration. For pulse durations of less than 2 s, both events interact with each other (Fig. 9). All of these results do not provide any indication that the fly processes motion information in independent ON and OFF motion detectors. Brightness changes of both signs are rather represented at the input of the same movement detectors, and interactions between signals resulting from both brightness increments and decrements take their sign into account. This type of preprocessing of the retinal input is argued to render a motion-detection system particularly robust against noise.

scholarly journals Implementation of Six Sigma in Supply Chain Management in Industries

2009 ◽  
pp. 141-144
Author(s):  
Himanshu S. Moharana ◽  
J.S. Murty ◽  
S. K. Senapati ◽  
K. Khuntia
Keyword(s):  
Supply Chain ◽  
Supply Chain Management ◽  
Six Sigma ◽  
Strategic Analysis ◽  
Process Mapping ◽  
Chain Management ◽  
Low Level ◽  
Implementation Model ◽  
High Level ◽  
Level Process

There is increasing concern about implementation failures in six sigma concept in supply chain management. The reason for many Six Sigma programmes to fail is due to an implementation model. Using a successful Six Sigma concept in an industry we have to perform strategic analysis driven by the market and the customer. It is necessary to establish a high- level, cross-functional team to drive the improvement initiative and to identify overall improvement tools. We can perform high-level process mapping and prioritize improvement opportunities. We have to develop a detailed plan for low-level improvement teams, and then to implement, document, and revise as necessary. This is important for both practitioners and academicians.

Local-Level and Global-Level Form Characteristics in Apparent-Motion Correspondence

Perception ◽  
1995 ◽  
Vol 24 (11) ◽  
pp. 1233-1245 ◽  
Author(s):  
Terry Palmer ◽  
Ovid J L Tzeng ◽  
Sheng He
Keyword(s):  
Apparent Motion ◽  
Motion Detection ◽  
Local Level ◽  
The Other ◽  
Correspondence Problem ◽  
Global Level ◽  
Global Precedence ◽  
Detection Mechanism ◽  
Motion Display ◽  
Motion Correspondence

This study addressed the ‘correspondence’ problem of apparent-motion (AM) perception in which parts of a scene must be matched with counterparts separated in time and space. Given evidence that AM correspondence can be mediated by two distinct processes—one based on a low-level motion-detection mechanism (the Reichardt process), the other involving the tracking of objects by visual attention (the attention-based process)—the present study explored how these processes interact in the perception of apparent motion between hierarchically structured figures. In three experiments, hierarchical figures were presented in a competition motion display so that, across frames, figures were identical at either the local or the global level. In experiment 1 it was shown that AM occurred between locally identical figures. Furthermore, with the Reichardt AM component eliminated in experiments 3 and 4, no preference was obtained for either level. While evidence from previous studies suggests that form extraction for hierarchically structured figures proceeds from the global to the local level, the present results indicate the irrelevance of such a global precedence in AM correspondence. In addition, it is suggested that Reichardt AM correspondence between local elements constrains attention-based AM correspondence between global figures so that both components move in the same direction. It is argued that this constraining process represents an elegant means of achieving AM correspondence between objects undergoing complex transformations.

THE COVID-19 FINANCIAL PROBLEMS AND ASPECTS OF AUDIT QUALITY ASSURANCE IN GEORGIA

2021 ◽  
Vol 16 (1(21)) ◽  
pp. 22-31
Author(s):  
David Bidzinashvili
Keyword(s):  
Audit Quality ◽  
International Standards ◽  
Time Interval ◽  
Second Stage ◽  
The World ◽  
Main Variable ◽  
The Subject ◽  
High Level ◽  
Two Stages ◽  
Working Out

The new Corona-virus and the contagious disease which it causes, the so called COVID 19, put forward the serious challenges for many countries all over the world and for Georgia among them. Almost the whole world is facing very serious obstacles on the international and national levels. Too many problems emerged in the world countries. To resist against the new disease has become the main priority for each country. The global processes caused by the pandemics have influenced the audit service as well. The uncertainty and unpredictability caused the new risks of deficiencies and activated already existed ones in the new environment. The situation became more complicated due to the fact that it can happen that the auditors do not consider the mentioned risks in the process of planning for audits or the risks may be considered mistakenly. The firms and other economical institutions in which the audit is carried out are obliged to adopt the new rules and changing environments in which their businesses function; they should change the rules of fulfilling the operation, preparing the financial accounts, the processes of their representing the information processes, safety of information shown in the financial accounts, the rules of their preparing; they also evaluate the possibilities of keeping on their activities in the nearest future. The qualified performing of the audit implies the basical elemenst which helps to create such environment where the possibility of the high level audit will be at the maximum. Implementing the quality control implies that such system will include two stages; each of them is directed towards providing the audit processes according the international standards There are several types of the quality improvement system. In all of them the main variable value represents the amount of costs for the proper system. All countries choose the system which provides benefits taking the costs into consideration. There are four main stages in the process of implementation the system which will ensure the high quality audit. Here are four main stages shown in the process of implementation:  The first stage: to carry out diagnostic observation;  The second stage: stating the view;  The third sage: working out the system;  The fourth stage: implementation of the system. The firms and other economical institutions where the audit is carried out are obliged to be reliable with their activities in the changing situation in which their businesses function. The subjects change the rules of carrying out the usual operations, change the open information given in the financial accounts, and estimate the possibilities of maintaining the existing possibilities for the nearest future. It is important to revise some standards out of Audit International Standards and to make them fit for revealing and assessing the risks of essential mistakes and discrepencies. The controlled variation of the standard regulates such issues as the newly corrected risks caused by influences of COVID-19 pandemic on the planned approaches to the audit and also, evaluation of the risks already defined and making changes in them taking into consideration the influence of the errors in the risk evaluations and influence made upon the planned evaluations and audits the changes of which will influence the evaluations of the risks in the inner control of the subject on the previously made imagination of the control environment, in order to define the measures to be taken in order to change the reactions to the mistakes using different measures in order to reach the trustful mechanisms to rely on. International standards of audit– answering to the assessed risks, the checked variation of the standard implies that it maybecome necessary to change the measures of reaction to the changes in the circumstances in order to obtain enough reliable measures and activities to control the situation by means of enough auditory evidences. The auditor has responsibilities to take into consideration that largening the deadlines will cause growth of the period and the risks of the dates of events which will happen in the time interval between accountability date and the date of the conclusion made by audit, the audit is also responsible for any event taking place later in relation to the Covid-19 situation. He is responsible also for evaluation of the fact about financial information. The enterprise functioning within nowadays complex environment taking into consideration the situation of COVID 19, should consider such priority issues as the uncertainty accompanying the Covid situation, related covenants, and others which accompany the pandemic period, among them the region, the financial state of customers and dealers, liquidating and paying capacity. During the process of the risk assessments it should considered that Covid 19 pandemic greatly influenced the global economics and the separate branches such as hotels business, retail sail, tourism and others. As a result of pandemic, it is possible that the number of audit considerations and thee circumstances can modify them which can be conditioned by different circumstances and the audit will state if there are incorrectable improper conditioned due to the circumstances. The audit will make it certain there are unimprovable mistakes which apart and together are essential for the financial accountability and the auditor will conclude that they cannot acquire the proper conditioned which apart or together could be essential financial accounts or the audit will conclude that they are not able to the essential accountability. Important researches were led to assess the appeared situation and it was concluded that the COVID 19 pandemic had influenced the financial situation which showed that the specific actions and procedures became complicated.

scholarly journals Time Petri Nets with Action Duration

2013 ◽  
Vol 4 (2) ◽  
pp. 62-83 ◽  
Author(s):  
N. Belala ◽  
D.E. Saїdouni ◽  
R. Boukharrou ◽  
A.C. Chaouche ◽  
A. Seraoui ◽  
...  
Keyword(s):  
Petri Nets ◽  
Real Time ◽  
Timed Automata ◽  
Operational Semantics ◽  
Time Interval ◽  
Timing Constraints ◽  
Time Petri Nets ◽  
Real Time Systems ◽  
High Level ◽  
Time Systems

The design of real-time systems needs a high-level specification model supporting at the same time timing constraints and actions duration. The authors introduce in this paper an extension of Petri Nets called Time Petri Nets with Action Duration (DTPN) where time is associated with transitions. In DTPN, the firing of transitions is bound to a time interval and transitions represent actions which have explicit durations. The authors give an operational semantics for DTPN in terms of Durational Action Timed Automata (DATA). DTPN considers both timing constraints and durations under a true-concurrency semantics with an aim of better expressing concurrent and parallel behaviours of real-time systems.

Study on a Decision Making Methodology with Uncertainties in the Selection Process of Preliminary Investigation Areas

2003 ◽  
Vol 807 ◽  
Author(s):  
Hiroyuki Tsuchi ◽  
Toshihiro Seo ◽  
Richard Metcalfe ◽  
Kenji Kawano ◽  
Hiroyasu Takase ◽  
...  
Keyword(s):  
Decision Making ◽  
Selection Process ◽  
Preliminary Investigation ◽  
Process Models ◽  
Evidential Support ◽  
High Level ◽  
Hlw Repository ◽  
Level Process ◽  
Specific Evaluation ◽  
Selection Of

ABSTRACTThe selection of Preliminary Investigation Areas (PIAs) to be considered in the siting procedure for a Japanese High Level Radioactive Waste (HLW) repository, will require Site-specific Evaluation Factors (SSEF) to be considered. Evaluation of these factors requires a methodology for taking into account various kinds of uncertainties in varied types of literature data. The study described here evaluated the application of Evidential Support Logic (ESL) for this purpose. The approach involves constructing hierarchical process models. Uncertainties are then propagated from the lowest processes, corresponding to data or information, through intermediate processes, to some top level process of interest, such as “assessing the existence of an active fault”. To evaluate the usefulness of ESL a hypothetical site was assessed. The results demonstrate the value of the approach to support decision-making in the selection of PIAs.

Biotic invasion, niche stability, and the assembly of regional biotas in deep time: comparison between faunal provinces

Paleobiology ◽  
2016 ◽  
Vol 42 (3) ◽  
pp. 359-379 ◽  
Author(s):  
Mark E. Patzkowsky ◽  
Steven M. Holland
Keyword(s):  
Late Ordovician ◽  
Niche Shift ◽  
Time Interval ◽  
Natural Experiments ◽  
Deep Time ◽  
Taconic Orogeny ◽  
Ecological Parameters ◽  
High Level ◽  
Biotic Invasion ◽  
Rank Abundance

AbstractBiotic invasions in the fossil record provide natural experiments for testing hypotheses of niche stability, speciation, and the assembly and diversity of regional biotas. We compare ecological parameters (preferred environment, occupancy, median abundance, rank abundance) of genera shared between faunal provinces during the Richmondian Invasion in the Late Ordovician on the Laurentian continent. Genera that spread from one faunal province to the other during the invasion (invading shared genera) have high Spearman rank correlations (>0.5) in three of four ecological parameters, suggesting a high level of niche stability among invaders. Genera that existed in both regions prior to and following the invasion (noninvading shared genera) have low correlations (<0.3) and suggest niche shift between lineages that diverged at least 8 Myr earlier. Niche shift did not accumulate gradually over this time interval but appears to have occurred in a pulse associated with the onset of the Taconic orogeny and the switch from warm-water to cool-water carbonates in southern Laurentia.

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