scholarly journals A Perceptually-Validated Metric for Crowd Trajectory Quality Evaluation

Author(s):  
Beatríz Cabrero Daniel ◽  
Ricardo Marques ◽  
Ludovic Hoyet ◽  
Julien Pettré ◽  
Josep Blat

Simulating crowds requires controlling a very large number of trajectories and is usually performed using crowd motion algorithms for which appropriate parameter values need to be found. The study of the relation between parametric values for simulation techniques and the quality of the resulting trajectories has been studied either through perceptual experiments or by comparison with real crowd trajectories. In this paper, we integrate both strategies. A quality metric, QF, is proposed to abstract from reference data while capturing the most salient features that affect the perception of trajectory realism. QF weights and combines cost functions that are based on several individual, local and global properties of trajectories. These trajectory features are selected from the literature and from interviews with experts. To validate the capacity of QF to capture perceived trajectory quality, we conduct an online experiment that demonstrates the high agreement between the automatic quality score and non-expert users. To further demonstrate the usefulness of QF, we use it in a data-free parameter tuning application able to tune any parametric microscopic crowd simulation model that outputs independent trajectories for characters. The learnt parameters for the tuned crowd motion model maintain the influence of the reference data which was used to weight the terms of QF.

2021 ◽  
Vol 11 (15) ◽  
pp. 6955
Author(s):  
Andrzej Rysak ◽  
Magdalena Gregorczyk

This study investigates the use of the differential transform method (DTM) for integrating the Rössler system of the fractional order. Preliminary studies of the integer-order Rössler system, with reference to other well-established integration methods, made it possible to assess the quality of the method and to determine optimal parameter values that should be used when integrating a system with different dynamic characteristics. Bifurcation diagrams obtained for the Rössler fractional system show that, compared to the RK4 scheme-based integration, the DTM results are more resistant to changes in the fractionality of the system.


2013 ◽  
Vol 28 (1) ◽  
pp. 18-31 ◽  
Author(s):  
T. G. Fawcett ◽  
C. E. Crowder ◽  
S. N. Kabekkodu ◽  
F. Needham ◽  
J. A. Kaduk ◽  
...  

Eighty specimens of cellulosic materials were analyzed over a period of several years to study the diffraction characteristics resulting from polymorphism, crystallinity, and chemical substitution. The aim of the study was to produce and verify the quality of reference data useful for the diffraction analyses of cellulosic materials. These reference data can be used for material identification, polymorphism, and crystallinity measurements. Overall 13 new references have been characterized for publication in the Powder Diffraction File (PDF) and several others are in the process of publication.


2011 ◽  
Vol 71 (6) ◽  
pp. 725-735 ◽  
Author(s):  
GM Subba Rao ◽  
T Vijayapushapm ◽  
K Venkaiah ◽  
V Pavarala

Objective: To assess quantity and quality of nutrition and food safety information in science textbooks prescribed by the Central Board of Secondary Education (CBSE), India for grades I through X. Design: Content analysis. Methods: A coding scheme was developed for quantitative and qualitative analyses. Two investigators independently coded the data and inter-coder reliability was assessed using Cohen’s Kappa. The inferences were then reviewed by an expert group. Results: There was high agreement (Kappa = 0.89) between coders. Nutrition topics got > 10% pages in textbooks of grades I to VII, while they were omitted in subsequent grades. Food safety got a mere 1% of page allocation only in grades I to III books. Over 25% of biology illustrations related to nutrition in grades I, II and IV but not in others. Nutrition topics in textbooks beyond grade IV were repetitive and inconsistent. Some illustrations depicted uncommon foods and had urban bias. Conclusions: Nutrition and food safety content in science textbooks is low. Important topics such as nutritional needs during adolescence, obesity, unhealthy foods and food labelling are not covered. These findings provide direction for strengthening textbook content to promote nutrition education in schools.


2019 ◽  
Vol 2 (2) ◽  
pp. 149-157
Author(s):  
Hendra Arianto ◽  
Sofyan M. Saleh ◽  
Renni Anggraini

Reuse of reclaimed asphalt pavement material (RAP) is an alternative which applicated for potential enough on the roughness of the road. RAP material can be reused by adding the asphalt and the new aggregate according of the mixture composition so that it is expected will be obtained the quality as planned. One of the efforts made in improving the quality of asphalt mixture RAP material is using a modified asphalt with additional material, such as styrofoam. The use of styrofoam into the asphalt is expected to improve the technical properties of a mixture. The purpose of this research is to know the comparative characteristics of hot mix asphalt (asphalt concrete) type AC-WC that uses RAP material with additional asphalt pen. 60/70 and asphalt pen. 60/70 substitution in the styrofoam by 8%, 10% and 12% against the weight of asphalt based on levels of asphalt left on the material. The initial stages of this study is to conduct an examination of the physical properties of RAP material, then manufacturing a specimen with variations of the addition of asphalt and aggregate new levels based on the job mix diesign (JMD) Bina Marga Aceh (2013). Based on research results, parameter values marshall on all types of asphalt mixture with new aggregate as well as RAP materials and the use of 100% asphalt pen. 60/70 additional or different types of asphalt on OAC has fulfilled the technical specifications defined by the Bina Marga (2014). Best stability values obtained on asphalt mixture using RAP material with additional asphalt pen. 60/70 with 12% styrofoam substitution on OAC JMD Bina Marga Aceh, that amounted to 3,308.72 kg, the lowest value stability retrieved on asphalt mixture using a new aggregate based on the results of Department of Bina Marga Aceh on OAC i.e. of 983.94 kg.


2022 ◽  
Vol 12 ◽  
Author(s):  
Silvia Seoni ◽  
Simeon Beeckman ◽  
Yanlu Li ◽  
Soren Aasmul ◽  
Umberto Morbiducci ◽  
...  

Background: Laser-Doppler Vibrometry (LDV) is a laser-based technique that allows measuring the motion of moving targets with high spatial and temporal resolution. To demonstrate its use for the measurement of carotid-femoral pulse wave velocity, a prototype system was employed in a clinical feasibility study. Data were acquired for analysis without prior quality control. Real-time application, however, will require a real-time assessment of signal quality. In this study, we (1) use template matching and matrix profile for assessing the quality of these previously acquired signals; (2) analyze the nature and achievable quality of acquired signals at the carotid and femoral measuring site; (3) explore models for automated classification of signal quality.Methods: Laser-Doppler Vibrometry data were acquired in 100 subjects (50M/50F) and consisted of 4–5 sequences of 20-s recordings of skin displacement, differentiated two times to yield acceleration. Each recording consisted of data from 12 laser beams, yielding 410 carotid-femoral and 407 carotid-carotid recordings. Data quality was visually assessed on a 1–5 scale, and a subset of best quality data was used to construct an acceleration template for both measuring sites. The time-varying cross-correlation of the acceleration signals with the template was computed. A quality metric constructed on several features of this template matching was derived. Next, the matrix-profile technique was applied to identify recurring features in the measured time series and derived a similar quality metric. The statistical distribution of the metrics, and their correlates with basic clinical data were assessed. Finally, logistic-regression-based classifiers were developed and their ability to automatically classify LDV-signal quality was assessed.Results: Automated quality metrics correlated well with visual scores. Signal quality was negatively correlated with BMI for femoral recordings but not for carotid recordings. Logistic regression models based on both methods yielded an accuracy of minimally 80% for our carotid and femoral recording data, reaching 87% for the femoral data.Conclusion: Both template matching and matrix profile were found suitable methods for automated grading of LDV signal quality and were able to generate a quality metric that was on par with the signal quality assessment of the expert. The classifiers, developed with both quality metrics, showed their potential for future real-time implementation.


2005 ◽  
Vol 129 (8) ◽  
pp. 997-1003 ◽  
Author(s):  
R. Neill Carey ◽  
George S. Cembrowski ◽  
Carl C. Garber ◽  
Zohreh Zaki

Abstract Context.—Proficiency testing (PT) participants can interpret their results to detect errors even when their performance is acceptable according to the limits set by the PT provider. Objective.—To determine which rules for interpreting PT data provide optimal performance for PT with 5 samples per event. Design.—We used Monte Carlo computer simulation techniques to study the performance of several rules, relating their error detection capabilities to (1) the analytic quality of the method, (2) the probability of failing PT, and (3) the ratio of the peer group SD to the mean intralaboratory SD. Analytic quality is indicated by the ratio of the PT allowable error to the intralaboratory SD. Failure of PT was defined (Clinical Laboratory Improvement Amendments of 1988) as an event when 2 or more results out of 5 exceeded acceptable limits. We investigated rules with limits based on the SD index, the mean SD index, and percentages of allowable error. Results.—No single rule performs optimally across the range of method quality. Conclusions.—We recommend further investigation when PT data cause rejection by any of the following 3 rules: any result exceeds 75% of allowable error, the difference between any 2 results exceeds 4 times the peer group SD, or the mean SD index of all 5 results exceeds 1.5. As method quality increases from marginal to high, false rejections range from 16% to nearly zero, and the probability of detecting a shift equal to 2 times the intralaboratory SD ranges from 94% to 69%.


Author(s):  
Steven Kim

We pass judgment on the value of scientific results. For example, we may feel that the periodic table of elements is of greater significance than the understanding that hydrogen is lighter than oxygen. For one thing, the latter fact may be deduced from an understanding of the periodic table. In this way, we may ascribe a measure of quality to an idea. The quality of an idea is subjective, and cannot be assigned an absolute value. However, it is possible to give a partial ordering and claim that idea A is of higher, lower, or equal worth in relation to idea B. The judgment of the relative importance of ideas is made routinely, for example, by an instructor in delivering a lecture or writing a book. The assignment of value occurs implicitly in the selection of topics and their relative emphasis. Once we admit a preference ordering among ideas, we may also assign an arbitrary numerical scale to them. This practice is standard in the field of economics, where a preference ordering among goods suggests a measure of utility. Since each consumer has individual tastes and needs, the resulting utility function varies from one person to another even for the same basket of goods. Further, the preferences are subjective and relative, rather than absolute. As a result, the level of utility can be based only on a conceptual scale. The basic measure of utility is an arbitrary unit called a util. In a similar way, we may assign a quality metric in terms of a granular unit of a qual. A person may assign a particular set of quals to a portfolio of ideas based on his own tastes and predilictions. A second person may offer a completely different set of quality values. This conception of an individual ordering of ideas is consistent with the view of difficulty and creativity as relative rather than absolute parameters. To pursue this line of reasoning, we may also speak of the combined quality of two or more ideas. The value of a set of ideas may be greater than, equal to, or less than the sum of the individual values.


Entropy ◽  
2019 ◽  
Vol 21 (8) ◽  
pp. 738 ◽  
Author(s):  
Łukasz Strąk ◽  
Rafał Skinderowicz ◽  
Urszula Boryczka ◽  
Arkadiusz Nowakowski

This paper presents a discrete particle swarm optimization (DPSO) algorithm with heterogeneous (non-uniform) parameter values for solving the dynamic traveling salesman problem (DTSP). The DTSP can be modeled as a sequence of static sub-problems, each of which is an instance of the TSP. In the proposed DPSO algorithm, the information gathered while solving a sub-problem is retained in the form of a pheromone matrix and used by the algorithm while solving the next sub-problem. We present a method for automatically setting the values of the key DPSO parameters (except for the parameters directly related to the computation time and size of a problem).We show that the diversity of parameters values has a positive effect on the quality of the generated results. Furthermore, the population in the proposed algorithm has a higher level of entropy. We compare the performance of the proposed heterogeneous DPSO with two ant colony optimization (ACO) algorithms. The proposed algorithm outperforms the base DPSO and is competitive with the ACO.


2008 ◽  
Vol 25 (No. 5) ◽  
pp. 249-258
Author(s):  
I. Švec ◽  
M. Hrušková ◽  
O. Jirsa

The effects of wheat cultivar and harvest year on the wheat technological quality were studied by univariate and multivariate statistical methods. Two wheat varieties sown in the harvest years 2003–2005 were used, the first one of European (cultivar Bezostaja, RUS), the second one of American origin (cultivar Jagger, USA). The evaluated parameter values indicated otherness of technological quality of the varieties studied, mostly in the milling effectivity and in proteins contents and quality. Principal component analysis (PCA) results suggested these differences, but their verifiability based on ANOVA testing was not proved. The harvest year mostly affected also the milling quality and alveograph parameters. The baking test results were not affected by either of both effects studied. The crop of 2003 had higher proximity to the crop of 2004 than to that of 2005. Multivariate analysis (cluster analysis; CA), was used to evaluate the interaction between the wheat cultivar and harvest year effects. In comparison of these effects rate, the technological quality of American cultivar Jagger was strongly influenced by the cultivar (with exception of Falling Number and gases volume). In contrast, the quality of the European wheat cultivar Bezostaja depended significantly on the harvest year.


2015 ◽  
Vol 43 (1) ◽  
pp. 179-185 ◽  
Author(s):  
Mihai STAVARACHE ◽  
Costel SAMUIL ◽  
Constantin I. POPOVICI ◽  
Doina TARCĂU ◽  
Vasile VÂNTU

Alternative use of alfalfa, for various purposes, including the production of biofuels or food supplement for human alimentation, is a study topic still in its early stages of research. Studying and understanding the biology of alfalfa and the factors with a major influence on it are very important activities. The productivity and quality of alfalfa are two indicators that help determine, in addition to economic value, the way in which alfalfa can be used. Evolution of alfalfa yield and quality depends on many factors, such as the growth stage of alfalfa plants at harvesting. It was observed over three years of vegetation the influence of alfalfa plant growth stage at harvest on plant height, leaves/stems ratio, production of leaves, stems and whole plant (DM - dry matter) per hectare and on quality indicators (CP - crude protein, NDF - neutral detergent fiber and ADF - acid detergent fiber). The results showed that, with the advancement of phenological phases, from early bud stage to complete flowering, the total biomass output raised from 2.79 Mg·ha-1 to 4.60 Mg·ha-1, the neutral detergent fiber raised from 48.4-50.6% to 62.0-67.7%, while crude protein content decreased from 21.2-24.0% to 13.3-16.5%. The parameter values were correlated with alfalfa growth stage during the harvesting (significant at the 0.05 and 0.01 probability levels).


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