scholarly journals Microsaccades during high speed continuous visual search

2020 ◽  
Author(s):  
Jacob G. Martin ◽  
Charles E. Davis ◽  
Maximilian Riesenhuber ◽  
Simon J. Thorpe
Keyword(s):  
Visual Search ◽  
High Speed ◽  
Visual Hierarchy ◽  
Trial Onset ◽  
The Face ◽  
Cluttered Background ◽  
Random Location ◽  
Pass Through ◽  
Task Oriented ◽  
Inverted Face

ABSTRACTHere, we provide an analysis of the microsaccades that occurred during continuous visual search and targeting of small faces that we pasted either into cluttered background photos or into a simple gray background. Subjects continuously used their eyes to target singular 3-degree upright or inverted faces in changing scenes. As soon as the participant’s gaze reached the target face, a new face was displayed in a different and random location. Regardless of the experimental context (e.g. background scene, no background scene), or target eccentricity (from 4 to 20 degrees of visual angle), we found that the microsaccade rate dropped to near zero levels within only 12 milliseconds after trial onset. There were almost never any microsaccades before the saccade to the face. One subject completed 118 consecutive trials without a single microsaccade. However, in about 20% of the trials, there was a single corrective microsaccade that occurred almost immediately after the preceding saccade’s offset. These corrective microsaccades were task oriented because their facial landmark targeting distributions matched those of saccades within both the upright and inverted face conditions. Our findings show that a single feedforward pass through the visual hierarchy for each stimulus is likely all that is needed to effectuate prolonged continuous visual search. In addition, we provide evidence that microsaccades can serve perceptual functions like correcting saccades or effectuating task-oriented goals during continuous visual search.

scholarly journals Microsaccades during high speed continuous visual search

2020 ◽  
Vol 13 (5) ◽  
Author(s):  
Jacob G. Martin ◽  
Charles E. Davis ◽  
Maximilian Riesenhuber ◽  
Simon J. Thorpe
Keyword(s):  
Visual Search ◽  
High Speed ◽  
Stimulus Onset ◽  
Visual Hierarchy ◽  
The Face ◽  
Cluttered Background ◽  
Random Location ◽  
Pass Through ◽  
Task Oriented ◽  
Inverted Face

Here, we provide an analysis of the microsaccades that occurred during continuous visual search and targeting of small faces that we pasted either into cluttered background photos or into a simple gray background.  Subjects continuously used their eyes to target singular 3-degree upright or inverted faces in changing scenes.  As soon as the participant’s gaze reached the target face, a new face was displayed in a different and random location.  Regardless of the experimental context (e.g. background scene, no background scene), or target eccentricity (from 4 to 20 degrees of visual angle), we found that the microsaccade rate dropped to near zero levels within only 12 milliseconds after stimulus onset.  There were almost never any microsaccades after stimulus onset and before the first saccade to the face.  One subject completed 118 consecutive trials without a single microsaccade.  However, in about 20% of the trials, there was a single microsaccade that occurred almost immediately after the preceding saccade’s offset.  These microsaccades were task oriented because their facial landmark targeting distributions matched those of saccades within both the upright and inverted face conditions.  Our findings show that a single feedforward pass through the visual hierarchy for each stimulus is likely all that is needed to effectuate prolonged continuous visual search.  In addition, we provide evidence that microsaccades can serve perceptual functions like correcting saccades or effectuating task-oriented goals during continuous visual search.

Gliding Flight of the White-Backed Vulture Gyps Africanus

1971 ◽  
Vol 55 (1) ◽  
pp. 13-38 ◽  
Author(s):  
C. J. PENNYCUICK
Keyword(s):  
High Speed ◽  
Lift Coefficient ◽  
The Body ◽  
East African ◽  
Induced Drag ◽  
Gliding Flight ◽  
Vertical Speed ◽  
Statistical Sense ◽  
Pass Through ◽  
Comparison Measurements

1. Glide-comparison measurements were made on ten species of East African soaring birds using a Schleicher ASK-14 powered sailplane. Horizontal and vertical speed differences between bird and glider were measured by a photographic method, and used to estimate the bird's horizontal and vertical speeds relative to the air. The analysis refers to the white-backed vulture, since by far the largest number of measurements was obtained on this species. 2. A regression analysis using a two-term approximation to the glide polar yielded an implausibly high estimate of induced drag, which was attributed to a lack of observations at lift coefficients above 0.72. An amended glide polar was constructed assuming elliptical lift distribution and a maximum lift coefficient of 1.6 to define the low-speed end, while the high-speed end was made to pass through the mean horizontal and sinking speeds of all the experimental points. This curve gave a minimum sinking speed of 0.76 m/s at a forward speed of 10 m/s, and a best glide ratio of 15.3:1 at 13 m/s. It did not differ significantly (in the statistical sense) from the original regression curve. 3. In comparing the estimated circling performance, based on the amended glide polar, with that of the ASK-14, it was concluded that the rates of sink of both should be comparable, but that the glider would require thermals with radii about 4.3 times as great as those needed to sustain the birds. The conclusions are consistent with experience of soaring in company with birds. 4. In an attempt to assess the adaptive significance of the low-aspect-ratio wings of birds specializing in thermal soaring, the white-backed vulture's circling performance was compared with that of an ‘albatross-shaped vulture’, an imaginary creature having the same mass as a white-backed vulture, combined with the body proportions of a wandering albatross. It appears that the real white-back would be at an advantage when trying to remain airborne in thermals with radii between 14 and 17 m, but that the albatross-shaped vulture would climb faster in all wider thermals; on account of its much better maximum glide ratio, it should also achieve higher cross-country speeds. It is concluded that the wing shape seen in vultures and storks is not an adaptation to thermal soaring as such, but is more probably a compromise dictated by take-off and landing requirements. 5. The doubts recently expressed by Tucker & Parrott (1970) about the results and conclusions of Raspet (1950a, b; 1960) are re-inforced by the present experience.

The Aerodynamic Characteristics of the Pantograph When the Train Passes Through the Tunnel

2017 ◽  
Author(s):  
Dilong Guo ◽  
Wen Liu ◽  
Junhao Song ◽  
Ye Zhang ◽  
Guowei Yang
Keyword(s):  
High Speed ◽  
Aerodynamic Force ◽  
Maximum Amplitude ◽  
Aerodynamic Characteristics ◽  
High Speed Train ◽  
Expansion Waves ◽  
Compression And Expansion ◽  
High Speed Trains ◽  
Current Characteristics ◽  
Pass Through

The aerodynamic force acting on the pantograph by the airflow is obviously unsteady and has a certain vibration frequency and amplitude, while the high-speed train passes through the tunnel. In addition to the unsteady behavior in the open-air operation, the compressive and expansion waves in the tunnel will be generated due to the influence of the blocking ratio. The propagation of the compression and expansion waves in the tunnel will affect the pantograph pressure distribution and cause the pantograph stress state to change significantly, which affects the current characteristics of the pantograph. In this paper, the aerodynamic force of the pantograph is studied with the method of the IDDES combined with overset grid technique when high speed train passes through the tunnel. The results show that the aerodynamic force of the pantograph is subjected to violent oscillations when the pantograph passes through the tunnel, especially at the entrance of the tunnel, the exit of the tunnel and the expansion wave passing through the pantograph. The changes of the pantograph aerodynamic force can reach a maximum amplitude of 106%. When high-speed trains pass through tunnels at different speeds, the aerodynamic coefficients of the pantographs are roughly the same.

scholarly journals ANALYSIS OF EXPERIENCE IN THE APPLICATION OF MISSILE LAUNCH DETECTION SYSTEMS

2021 ◽  
pp. 118-129
Author(s):  
A. Pinchuk ◽  
M. Garbuz ◽  
P. Zeleny ◽  
D. Harnets ◽  
D. Ivanov
Keyword(s):  
High Speed ◽  
Armed Forces ◽  
The United States ◽  
Armed Conflicts ◽  
Desert Storm ◽  
Detection Systems ◽  
The Face ◽  
Protected Object ◽  
Conducting Research ◽  
The Impact

Analysis of combat losses of aircraft in local armed conflicts in recent decades shows that most cases of aircraft hits are related to the impact of guided surface-to-air and air-to-air missiles equipped with homing warheads. The use of modern guided missiles equipped with homing warheads is one of the main threats to aircraft of various types. This is due to the fact that modern guided missiles are characterized by high speed, maneuverability, accuracy of aiming and difficulty of detection. Solving the problem of protecting aircraft from guided missiles consists of several stages: detection of missile launch; confirmation that the detected missile is heading directly toward the protected object; missile identification and decision-making on the most effective countermeasure system employment. At present, there are no missile launch detection systems that guarantee a 100% probability of threat detection, but an analysis of aviation combat losses in local armed conflicts in recent decades convincingly shows that the number of combat losses of aircraft equipped with such systems is much lower than those in which missile launch detection is carried out visually. For example, most of the Soviet Union's losses during the war in Afghanistan and the United States‟ losses during Operation “Desert Storm” in Iraq were related to the use of portable anti-aircraft missile systems, which missiles were equipped with infrared homing warheads. Realizing the scale of the threat posed by such missiles, most of the world's leading countries have significantly increased the expenses on development new or improvement existing countermeasures. As a result, the aggregate losses of coalition forces in Iraq, Afghanistan and Syria since 2001 clearly suggest that these costs have paid off, with losses from the use of portable anti-aircraft missile systems significantly reduced, while the total number of combat sorties increased. Therefore, in the face of all the challenges and threats posed to Ukraine due to the aggressive actions of the Russian Federation, conducting research in the interests of aviation of the Armed Forces of Ukraine to improve the effectiveness of missile detection systems for ensuring timely detection of threats, warning of aircraft crew and activation in the automatic mode the means of countermeasures is as relevant as ever.

scholarly journals New Dzungaria Gates for wmlt-corridor: historical necessity

2019 ◽  
Vol 5 (3) ◽  
pp. 36-44
Author(s):  
Viktor A. Bogachev ◽  
Yuri A. Terentyev ◽  
Viktor V. Koledov ◽  
Taras V. Bogachev
Keyword(s):  
Mathematical Models ◽  
Variational Methods ◽  
High Speed ◽  
Optimization Problem ◽  
Point Of View ◽  
The North ◽  
Computer Math ◽  
Pass Through ◽  
Historical Necessity ◽  
North Western

Background: Research is ongoing relating to the analysis of a set of issues that arise in connection with the creation of the operating on the basis of vacuum magnetic technologies a transcontinental high-speed land transport corridor, connecting the eastern regions of China with Russia. As part of the variation calculus task, the geopolitical, economic, social, logistic, geographic, geomorphological, seismological, topographic components of the project are considered, in which it is assumed that the high speed overland route will pass through the north-western part of the historical region of Dzungaria. Aim: Find the most optimal from the point of view of the above components the location of the most important section of high speed overland route passing through Central Asia. Methods: Variational methods for solving an optimization problem with the use of a computer math system. Results: After creating a fairly informative and versatile picture of the region in question, the foundations of the corresponding mathematical models are built. Conclusion: The New Dzungarian Gates is a key element in choosing the location of a high-speed overland route based on VMLT.

A measurement method for the overturning coefficient of high-speed trains passing through complex terrain sections under strong wind conditions

2019 ◽  
Vol 234 (8) ◽  
pp. 885-895
Author(s):  
Zhaijun Lu ◽  
Weijia Huang ◽  
Mu Zhong ◽  
Dongrun Liu ◽  
Tian Li ◽  
...  
Keyword(s):  
Real Time ◽  
Complex Terrain ◽  
High Speed ◽  
Suspension System ◽  
Strong Wind ◽  
Real Time Monitoring ◽  
Monitoring Method ◽  
High Speed Trains ◽  
Strong Winds ◽  
Pass Through

Real-time monitoring of overturning coefficients is very important for ensuring the safety of high-speed trains passing through complex terrain sections under strong wind conditions. In recent years, the phenomenon of “car swaying” that occurs when trains pass through the complex terrain has brought new challenges to ensuring the safety and riding comfort of passengers. In China, more and more high-speed trains are facing strong wind environments when running in complex terrain sections. However, due to the limitation of objective conditions, so far, only a few economical and effective methods of measurement have been developed that are suitable for real-time monitoring of the overturning coefficient of commercial vehicles. Therefore, considering the applicability and universality of such a monitoring method, this study presents a method for measuring the overturning coefficient of trains using the primary suspension system under strong winds. A vehicle test was carried out to verify the accuracy of the method. The results show that after correction, the overturning coefficient obtained from the primary suspension system is generally consistent with the overturning coefficient obtained from the instrumented wheelset. The method of measuring the overturning coefficient of trains in strong wind environments with the primary suspension system is, thus, proven feasible.

Impact of Spatial Filtering on the Least Cost Path Method

2010 ◽  
Vol 1 (4) ◽  
pp. 32-44
Author(s):  
Amy E. Rock ◽  
Amanda Mullett ◽  
Saad Algharib ◽  
Jared Schaffer ◽  
Jay Lee
Keyword(s):  
Land Cover ◽  
High Speed ◽  
Least Cost Path ◽  
High Speed Rail ◽  
Highway Infrastructure ◽  
Advantages And Disadvantages ◽  
Passenger Rail ◽  
The Face ◽  
Cost Paths ◽  
Cost Factors

In the face of renewed interest in High-Speed Rail (HSR) projects, Ohio is one of several states seeking federal funding to relieve pressure on aging, overburdened highway infrastructure by constructing passenger rail routes between major cities. This paper evaluates the creation of a new rail route in Ohio’s 3-C Corridor utilizing GIS. The authors consider two primary cost factors in construction, slope and land cover, to generate alternative least-cost paths. To assess the importance of the cost factors, two separate paths are created using two different weighting methods for the land cover layer. The land cover is weighted first by difficulty of construction, and second by relative acquisition costs. These two paths are then compared against a path selected by the Ohio Hub Project which uses existing track lines, advantages and disadvantages of each are discussed.

scholarly journals CSR Communication, Corporate Reputation, and the Role of the News Media as an Agenda-Setter in the Digital Age

2020 ◽  
pp. 000765032092896
Author(s):  
Daniel Vogler ◽  
Mark Eisenegger
Keyword(s):  
Social Media ◽  
News Media ◽  
Corporate Reputation ◽  
Media Coverage ◽  
Digital Age ◽  
The Public ◽  
Csr Communication ◽  
Agenda Setter ◽  
The Face ◽  
Pass Through

By using social media, corporations can communicate about their corporate social responsibility (CSR) to the public without having to pass through the gatekeeping function of the news media. However, to what extent can corporations influence the public’s evaluation of their CSR activities with social media activities and if the legacy news media still act as the primary agenda setters when it comes to corporate reputation have not yet been thoroughly analyzed in a digitized media environment. This study addressed this research gap by looking at the effect of CSR communication through Facebook and news media coverage of CSR on corporate reputation in Switzerland. The results of this longitudinal study show that the salience and tone of news media coverage of CSR were positively related to corporate reputation, even though the news media coverage about CSR was predominantly negative. Thus, reputation was still strengthened even in the face of negative publicity. No effect of CSR communication through Facebook on corporate reputation was found. The results suggest that legacy news media still were influential in determining how the public evaluates corporations in the digital age.

scholarly journals A Novel Approach to Reduce the Unicast Bandwidth of an IPTV System in a High-Speed Access Network

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
El Hassane Khabbiza ◽  
Rachid El Alami ◽  
Hassan Qjidaa
Keyword(s):  
High Speed ◽  
Access Network ◽  
Channel Change ◽  
Set Top Box ◽  
Novel Approach ◽  
Assisted Delivery ◽  
High Bandwidth ◽  
Internet Protocol Television ◽  
Unicast Traffic ◽  
Pass Through

Channel change time is a critical quality of experience (QOE) metric for IP-based video delivery systems such as Internet Protocol Television (IPTV). An interesting channel change acceleration scheme based on peer-assisted delivery was recently proposed, which consists of deploying one FCC server (Fast Channel Change Server) in the IP backbone in order to send the unicast stream to the STB (Set-Top Box) before sending the normal multicast stream after each channel change. However, deploying such a solution will cause high bandwidth usage in the network because of the huge unicast traffic sent by the FCC server to the STBs. In this paper, we propose a new solution to reduce the bandwidth occupancy of the unicast traffic, by deploying the FCC server capabilities on the user STB. This means that, after each channel change request, the STB will receive the unicast traffic from another STB instead of the central server. By using this method, the unicast traffic will not pass through the IP network; it will be a peer-to-peer communication via the Access Network only. Extensive simulation results are presented to demonstrate the robustness of our new solution.

scholarly journals Distal convoluted tubule sexual dimorphism revealed by advanced 3D imaging

2020 ◽  
Vol 319 (5) ◽  
pp. F754-F764
Author(s):  
Ebrahim Tahaei ◽  
Richard Coleman ◽  
Turgay Saritas ◽  
David H. Ellison ◽  
Paul A. Welling
Keyword(s):  
Sexual Dimorphism ◽  
High Speed ◽  
Distal Convoluted Tubule ◽  
Volumetric Imaging ◽  
Female Mice ◽  
Cellular Density ◽  
The Face ◽  
Antibody Labeling ◽  
Male Subjects ◽  
Insight Into

The thiazide-sensitive Na+-Cl− cotransporter (NCC) is more abundant in kidneys of female subjects than of male subjects. Because morphological remodeling of the distal convoluted tubule (DCT) is dependent on NCC activity, it has been generally assumed that there is a corresponding sexual dimorphism in the structure of the DCT, leading to a larger female DCT. Until now, this has never been directly examined. Here, optical clearing techniques were combined with antibody labeling of DCT segment markers, state-of-the-art high-speed volumetric imaging, and analysis tools to visualize and quantify DCT morphology in male and female mice and study the DCT remodeling response to furosemide. We found an unexpected sex difference in the structure of the DCT. Compared with the male mice, female mice had a shorter DCT, a higher cellular density of NCC, and a greater capacity to elongate in response to loop diuretics. Our study revealed a sexual dimorphism of the DCT. Female mice expressed a greater density of NCC transporters in a shorter structure to protect Na+ balance in the face of greater basal distal Na+ delivery yet have a larger reserve and structural remodeling capacity to adapt to unique physiological stresses. These observations provide insight into mechanisms that may drive sex differences in the therapeutic responses to diuretics.

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