scholarly journals Extending Levelt’s Propositions to perceptual multistability involving interocular grouping

2016 ◽  
Author(s):  
Alain Jacot-Guillarmod ◽  
Yunjiao Wang ◽  
Claudia Pedroza ◽  
Haluk Ogmen ◽  
Zachary Kilpatrick ◽  
...  
Keyword(s):  
Hierarchical Model ◽  
Color Image ◽  
Stimulus Strength ◽  
Low Level ◽  
Color Saturation ◽  
Modeling Studies ◽  
Visual Hemifield ◽  
Neural Populations ◽  
The Difference ◽  
Dominance Duration

AbstractLevelt’s Propositions have been a touchstone for experimental and modeling studies of perceptual multistability. We asked whether Levelt’s Propositions extend to perceptual multistability involving interocular grouping. To address this question we used split-grating stimuli withcomplementary halves of the same color. As in previous studies, subjects reported four percepts in alternation: the two stimuli presented to each eye (single-eye percepts), as well as two interocularly grouped, single color percepts (grouped percepts). Most subjects responded to increased color saturation by more frequently reporting a single color image, thus increasingthe predominance of grouped percepts (Levelt’s Proposition I). In these subjects increased predominance was due to a decrease in the average dominance duration of single-eye percepts, while that of grouped percepts remained largely unaffected. This is in accordance with generalized Levelt’s Proposition II which posits that the average dominance duration of the stronger (in this case single-eye) percept is primarily affectedbychanges in stimulus strength. In accordance with Proposition III, thealternation rate increased as the difference in the strength of the percepts decreased. To explain the mechanism behind these observations, we introduce a hierarchical model consisting of low-level neural populations, eachresponding to input at a visual hemifield, and higher-level populations representing the percepts. The model exhibits the changes in dominance durationobserved in the data, and conforms to all of Levelt’s Propositions.

scholarly journals Primary School Student Teachers’ Perceived and Actual Knowledge in Biology

2017 ◽  
Vol 7 (4) ◽  
pp. 125-146
Author(s):  
Eija Yli-Panula ◽  
Elia Jeronen ◽  
Nonmanut Pongsakdi
Keyword(s):  
Student Teachers ◽  
Perceived Knowledge ◽  
Actual Knowledge ◽  
Low Level ◽  
Work Related ◽  
Cluster Group ◽  
Primary School Student ◽  
Study Programme ◽  
The Difference ◽  
Knowledge Strategies

Individuals’ perceptions of their knowledge can have an important role in shaping their cognition and influencing their behaviour. However, there has been a scarcity of studies in biology on how perceived knowledge relates to actual knowledge. The focus of this article is on quantitative results analysing and interpreting student teachers’ perceived knowledge of biological content in relation to their actual animal and species name knowledge linked to the ecosystem in which they live. K-means cluster analysis and ANOVA were used. The results show a high- and low-level perceived knowledge cluster group among the participants. They further indicate that the difference in actual animal and species name knowledge betweenthese cluster groups remained the same during the five years of the study. The student teachers with a higher level of perceived knowledge tended to have better actual animal and species name knowledge than those in the low-level group. The actual animal name knowledge in these cluster groups was similar with regard to the local Finnish ecosystems but differed concerning the exotic species by year. The year that the participants enrolled in the study programme had an impact on their actual animal and species name knowledge. Strategies for coping with work-related demands and maintaining engagement in one’s career would be important additions to the teacher education curriculum.

scholarly journals Comparing two years of Saharan dust source activation obtained by regional modeling and satellite observations

2012 ◽  
Vol 12 (10) ◽  
pp. 27667-27691
Author(s):  
I. Tegen ◽  
K. Schepanski ◽  
B. Heinold
Keyword(s):  
Regional Scale ◽  
Dust Emission ◽  
Saharan Dust ◽  
Strong Increase ◽  
Dust Source ◽  
Low Level ◽  
Mountainous Regions ◽  
Emission Fluxes ◽  
Low Level Jets ◽  
The Difference

Abstract. A regional-scale dust model is used to simulate Saharan dust emissions and atmospheric distributions in the years 2007 and 2008. The model results are compared to dust source activation events compiled from infrared dust index imagery from the geostationary Meteosat Second Generation (MSG) satellite. The observed morning maximum in dust source activation frequencies indicates that the breakdown of nocturnal low-level jets is responsible for a considerable number of dust source activation events in the Sahara. The comparison shows that the time of the day of the onset of dust emission is delayed in the model compared to the observations. Also, the simulated number of dust emission events associated with nocturnal low level jets in mountainous regions is underestimated in the model. The MSG dust index observations indicate a strong increase in dust source activation frequencies in the year 2008 compared to 2007, the difference between the two years is less pronounced in the model. The quantitative comparison of simulated dust optical thicknesses with observations at stations of the sunphotometer network AERONET shows, however, good agreement for both years, indicating that the number of observed dust activation events is only of limited use for estimating actual dust emission fluxes in the Sahara.

scholarly journals Enhancement of Satellite Imagesusing Image Sharpening Technique

2019 ◽  
Vol 8 (6S2) ◽  
pp. 351-354
Keyword(s):  
Image Processing ◽  
Color Image ◽  
Histogram Equalization ◽  
Grayscale Image ◽  
Original Image ◽  
High Quality ◽  
Wide Range ◽  
Equalization Technique ◽  
The Difference

In many image processing applications, a wide range of image enhancement techniques are being proposed. Many of these techniques demanda lot of critical and advance steps, but the resultingimage perception is not satisfactory. This paper proposes a novel sharpening method which is being experimented with additional steps. In the first step, the color image is transformed into grayscale image, then edge detection process is applied using Laplacian technique. Then deduct this image from the original image. The resulting image is as expected; After performing the enhancement process,the high quality of the image can be indicated using the Tenengrad criterion. The resulting image manifested the difference in certain areas, the dimension and the depth as well. Histogram equalization technique can also be applied to change the images color.

scholarly journals Static Profiling of Assembly Code Performance and Optimization Effectiveness using Instructions Performed and Program Latency

2019 ◽  
Vol 8 (2S8) ◽  
pp. 1463-1468
Keyword(s):  
Assembly Language ◽  
Optimization Method ◽  
Program Optimization ◽  
Low Level ◽  
Code Performance ◽  
Execution Speed ◽  
The Difference ◽  
And Performance ◽  
High Level ◽  
Optimization And Performance

Software program optimization for improved execution speed can be achieved through modifying the program. Programs are usually written in high level languages then translated into low level assembly language. More coverage of optimization and performance analysis can be performed on low level than high level language. Optimization improvement is measured in the difference in program execution performance. Several methods are available for measuring program performance are classified into static approaches and dynamic approaches. This paper presents an alternative method of more accurately measuring code performance statically than commonly used code analysis metrics. New metrics proposed are designed to expose effectiveness of optimization performed on code, specifically unroll optimizations. An optimization method, loop unroll is used to demonstrate the effectiveness of the increased accuracy of the proposed metric. The results of the study show that measuring Instructions Performed and Instruction Latency is a more accurate static metric than Instruction Count and subsequently those based on it.

scholarly journals Comparing two years of Saharan dust source activation obtained by regional modelling and satellite observations

2013 ◽  
Vol 13 (5) ◽  
pp. 2381-2390 ◽  
Author(s):  
I. Tegen ◽  
K. Schepanski ◽  
B. Heinold
Keyword(s):  
Regional Scale ◽  
Dust Emission ◽  
Saharan Dust ◽  
Strong Increase ◽  
Regional Modelling ◽  
Dust Source ◽  
Low Level ◽  
Mountainous Regions ◽  
Low Level Jets ◽  
The Difference

Abstract. A regional-scale dust model is used to simulate Saharan dust emissions and atmospheric distributions in the years 2007 and 2008. The model results are compared to dust source activation events compiled from infrared dust index imagery from the geostationary Meteosat Second Generation (MSG) satellite. The observed morning maximum in dust source activation frequencies indicates that the breakdown of nocturnal low level jets is an important mechanism for dust source activation in the Sahara. The comparison shows that the time of the day of the onset of dust emission is delayed in the model compared to the observations. Also, the simulated number of dust emission events associated with nocturnal low level jets in mountainous regions is underestimated in the model. The MSG dust index observations indicate a strong increase in dust source activation frequencies in the year 2008 compared to 2007. The difference between the two years is less pronounced in the model. Observations of dust optical thickness, e.g. at stations of the sunphotometer network AERONET, do not show such increase, in agreement with the model results. This indicates that the number of observed dust activation events is only of limited use for estimating actual dust emission fluxes in the Sahara. The ability to reproduce interannual variability of Saharan dust with models remains an important challenge for understanding the controls of the atmospheric dust load.

The impact of London on a low-level jet

2021 ◽  
Author(s):  
Aristofanis Tsiringakis ◽  
Natalie Theeuwes ◽  
Janet Barlow ◽  
Gert-Jan Steeneveld
Keyword(s):  
Urban Area ◽  
Prediction Models ◽  
Weather Prediction ◽  
Vertical Mixing ◽  
Forecasting Model ◽  
Low Level ◽  
Low Level Jet ◽  
The Difference ◽  
The Impact ◽  
Numerical Weather Prediction Models

<p>The low-level jet (LLJ) is an important phenomenon that can affect (and is affected by) the turbulence in the nocturnal urban boundary layer (UBL). We investigate the interaction of a regional LLJ with the UBL during a 2-day period over London. Observations from two Doppler Lidars and two numerical weather prediction models (Weather Research & Forecasting model and UKV Met Office Unified Model) are used to compared the LLJ characteristics (height, speed and fall-off) between a urban (London) and a rural (Chilbolton) site. We find that LLJs are elevated (70m) over London, due to the deeper UBL, an effect of the increased vertical mixing over the urban area and the difference in the topography between the two sites. Wind speed and fall-off are slightly reduced with respect to the rural LLJ. The effects of the urban area and the surrounding topography on the LLJ characteristics over London are isolated through idealized sensitivity experiments. We find that topography strongly affects the LLJ characteristics (height, falloff, and speed), but there is still a substantial urban influence.</p>

THE LEED-COMMERCIAL INTERIORS (V4) PROJECTS IN CALIFORNIA

2021 ◽  
Vol 16 (3) ◽  
pp. 57-72
Author(s):  
Svetlana Pushkar
Keyword(s):  
Green Building ◽  
Nonparametric Tests ◽  
Indoor Environmental Quality ◽  
Positive Correlation ◽  
Low Level ◽  
Impact Reduction ◽  
Environmental Product Declarations ◽  
The Difference ◽  
High Level ◽  
Building Standards

ABSTRACT This study analyzed the Leadership in Energy and Environmental Design for Commercial Interior Certified, Silver, and Gold projects version 4.0 (LEED-CIv4) in California for the period 2015‒2020. Nonparametric tests were used to assess category and credit achievement, i.e., the difference between possible and achieved points and the correlation between associated credits. The results show that most of the credits in the location and transportation category and the indoor environmental quality categories had a high level of achievement, a few credits in the energy and atmosphere and materials and resources categories had a high level of achievement, and all of the credits in the water efficiency category had a low level of achievement. Some associated credits, such as surrounding density and quality transit, had a high level of achievement and a positive correlation, whereas other associated credits, such as life-cycle impact reduction and environmental product declarations, had a low level of achievement and a positive correlation. If LEED-CIv4 credits meet the requirements of the California Green Building Standards Code 2016 (CGBSC 2016), then these credits typically have a medium/high level of achievement. If LEED-CIv4 credits exceed the requirements of CGBSC 2016, then these credits have a low level of achievement. Therefore, to improve the next version of LEED-CI, it is necessary to improve the local green codes.

Studies of Blood Lipid Fractions of Quiescent Rheumatic Fever Patients and Their Siblings

1959 ◽  
Vol 5 (6) ◽  
pp. 557-565 ◽  
Author(s):  
Harold D Appleton ◽  
Alvin F Coburn ◽  
Yale L Meltzer
Keyword(s):  
Rheumatic Fever ◽  
Normal Level ◽  
Plasma Levels ◽  
Blood Lipids ◽  
Lipid Fraction ◽  
Blood Lipid ◽  
Low Level ◽  
Lipid Fractions ◽  
The Difference

Abstract Three phospholipid fractions have been determined in plasmas of quiescent rheumatic children and their siblings of similar ages. The method for determining blood lecithin gave reproducible results, and the lipid fraction appeared indicative of difference in levels of blood lipids between rheumatic and nonrheumatic children. In this series of lecithin determinations only one rheumatic subject had a high normal level and only one sibling (presumably nonrheumatic) had a low level. The difference in mean nonfasting lecithin plasma levels between rheumatic subjects and siblings was 0.36 mMol./L. Similarly, the lecithin level of each of the nonrheumatic siblings in this series averaged 0.41 mMol./L. higher than that of the corresponding quiescent rheumatic child. In both of these differences P <0.05.

Hybrid Method for Vehicle Detection from CCTV Captured Image

2013 ◽  
Vol 677 ◽  
pp. 412-417
Author(s):  
Suppatoomsin Chompoo ◽  
Srikaew Arthit
Keyword(s):  
Hybrid Method ◽  
Color Image ◽  
Principal Component ◽  
Vehicle Detection ◽  
Self Organizing Map ◽  
Resonance Theory ◽  
Difference Image ◽  
Fuzzy Art ◽  
Image Area ◽  
The Difference

This paper presents a hybrid method for vehicle detection from CCTV captured image. In order to overwhelm such complex details of the color image, the system combines artificial intelligence techniques to achieve automatic vehicle detection. These are techniques 2D principal component analysis (2DPCA), Fuzzy adaptive resonance theory (Fuzzy ART), genetic algorithm (GA) and self-organizing map. The proposed system can detect different vehicle sizes from different proportional image area. Bilinear interpolation is used to resize each proportional image area to vehicle feature matrix. The proposed system can detect various types of vehicles from the difference image background.

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