scholarly journals Estimating the Necessary Amount of Driving Data for Assessing Driving Behavior

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2600 ◽  
Author(s):  
Anna-Maria Stavrakaki ◽  
Dimitrios I. Tselentis ◽  
Emmanouil Barmpounakis ◽  
Eleni I. Vlahogianni ◽  
George Yannis
Keyword(s):  
Discrete Time ◽  
Driving Behavior ◽  
Methodological Framework ◽  
Detailed Data ◽  
Specific Time ◽  
Speed Limits ◽  
Specific Time Point ◽  
Smartphone Sensors ◽  
Over Time ◽  
Time Point

The aim of this paper was to provide a methodological framework for estimating the amount of driving data that should be collected for each driver in order to acquire a clear picture regarding their driving behavior. We examined whether there is a specific discrete time point for each driver, in the form of total driving duration and/or the number of trips, beyond which the characteristics of driving behavior are stabilized over time. Various mathematical and statistical methods were employed to process the data collected and determine the time point at which behavior converges. Detailed data collected from smartphone sensors are used to test the proposed methodology. The driving metrics used in the analysis are the number of harsh acceleration and braking events, the duration of mobile usage while driving and the percentage of time driving over the speed limits. Convergence was tested in terms of both the magnitude and volatility of each metric for different trips and analysis is performed for several trip durations. Results indicated that there is no specific time point or number of trips after which driving behavior stabilizes for all drivers and/or all metrics examined. The driving behavior stabilization is mostly affected by the duration of the trips examined and the aggressiveness of the driver.

scholarly journals Consistency in mutualism relies on local, rather than wider community biodiversity

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Katie Dunkley ◽  
Jo Cable ◽  
Sarah E. Perkins
Keyword(s):  
Biodiversity Loss ◽  
Context Dependency ◽  
Third Party ◽  
Interaction Patterns ◽  
Specific Time ◽  
Specific Time Point ◽  
Service Resource ◽  
Resource Mutualism ◽  
Time Point

AbstractMutualistic interactions play a major role in shaping the Earth’s biodiversity, yet the consistent drivers governing these beneficial interactions are unknown. Using a long-term (8 year, including > 256 h behavioural observations) dataset of the interaction patterns of a service-resource mutualism (the cleaner-client interaction), we identified consistent and dynamic predictors of mutualistic outcomes. We showed that cleaning was consistently more frequent when the presence of third-party species and client partner abundance locally increased (creating choice options), whilst partner identity regulated client behaviours. Eight of our 12 predictors of cleaner and client behaviour played a dynamic role in predicting both the quality (duration) and quantity (frequency) of interactions, and we suggest that the environmental context acting on these predictors at a specific time point will indirectly regulate their role in cleaner-client interaction patterns: context-dependency can hence regulate mutualisms both directly and indirectly. Together our study highlights that consistency in cleaner-client mutualisms relies strongly on the local, rather than wider community—with biodiversity loss threatening all environments this presents a worrying future for the pervasiveness of mutualisms.

scholarly journals Imputation algorithm using copulas

2006 ◽  
Vol 3 (1) ◽  
Author(s):  
Ene Käärik
Keyword(s):  
Conditional Distribution ◽  
Joint Distribution ◽  
Missing Values ◽  
Repeated Measurements ◽  
Specific Time ◽  
Marginal Distributions ◽  
Specific Time Point ◽  
Compound Symmetry ◽  
Time Point

In this paper the author demonstrates how the copulas approach can be used to find algorithms for imputing dropouts in repeated measurements studies. One problem with repeated measurements is the knowledge that the data is described by joint distribution. Copulas are used to create the joint distribution with given marginal distributions. Knowing the joint distribution we can find the conditional distribution of the measurement at a specific time point, conditioned by past measurements, and this will be essential for imputing missing values. Using Gaussian copulas, two simple methods for imputation are presented. Compound symmetry and the case of autoregressive dependencies are discussed. Effectiveness of the proposed approach is tested via series of simulations and results showing that the imputation algorithms based on copulas are appropriate for modelling dropouts.

Developmental toxicity of flucytosine following administration to pregnant rats at a specific time point of organogenesis

2018 ◽  
Vol 59 (2) ◽  
pp. 39-42 ◽  
Author(s):  
Sakiko Fujii ◽  
Kaoru Yabe ◽  
Yuki Kariwano-Kimura ◽  
Masatoshi Furukawa ◽  
Kouta Itoh ◽  
...  
Keyword(s):  
Developmental Toxicity ◽  
Specific Time ◽  
Pregnant Rats ◽  
Specific Time Point ◽  
Time Point

I-states-as-objects-analysis (ISOA): Extensions of an approach to studying short-term developmental processes by analyzing typical patterns

2012 ◽  
Vol 36 (3) ◽  
pp. 237-246 ◽  
Author(s):  
Lars R. Bergman ◽  
Jari-Erik Nurmi ◽  
Alexander A. von Eye
Keyword(s):  
Longitudinal Data ◽  
Developmental Stability ◽  
Specific Time ◽  
Short Term ◽  
Classification Analysis ◽  
Stability And Change ◽  
Children's Achievement ◽  
Specific Time Point ◽  
Time Invariant ◽  
Time Point

I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the i-state, defined as a person’s pattern of variable values at a specific time point. All i-states are first subjected to a classification analysis that results in a time-invariant classification characterized by a number of typical i-states. Each person is then characterized at each time point by the typical i-state he/she belongs to. Then the person’s sequences of typical i-states are analyzed with regard to structural and individual stability and change. Extensions of ISOA are presented where: (1) some methods for checking the assumption of a time-invariant classification are indicated; (2) information about the degree of dissimilarity between typical i-states is used as an aid in interpreting the findings; and (3) attention is given to closed paths—that is, typical i-state sequences that do not occur at all. To demonstrate the methods, an empirical example is given that concerns the development of children’s achievement-intelligence patterns between ages 10 and 13.

The ecology of social time: An outline of an empirical analytic framework of the sociology of time

2015 ◽  
Vol 26 (2) ◽  
pp. 137-164 ◽  
Author(s):  
Tsuo-Yu Cheng
Keyword(s):  
Social Interactions ◽  
Empirical Research ◽  
Ecological Model ◽  
Specific Time ◽  
Analytic Framework ◽  
Social Time ◽  
Social Actions ◽  
The Social ◽  
Specific Time Point ◽  
Time Point

The purpose of this paper is to outline the “ecology of social time” as an empirical concept of time to bridge the gap between theory and empirical research in the sociology of time. First, this paper proposes that social time could be considered as an institutionalized referential mechanism that enables social interactions to occur at a specific time point by coordinating the social actions of various agents. Examining the condition of temporal coordination and diagnosing its fairness critically may be the tasks involved in the sociology of time. Second, this paper suggests that the ecology of social time is a useful concept for integrating the theses and tasks applied in the sociology of time. Finally, this paper presents an ecological model of social time as a possible framework for subsequent empirical research in the sociology of time.

Assessing Patient State and Efficacy

2018 ◽  
pp. 26-32
Author(s):  
Joseph P. Cravero
Keyword(s):  
Procedural Sedation ◽  
Imaging Procedures ◽  
Specific Time ◽  
Painful Procedure ◽  
Specific Time Point ◽  
Patient State ◽  
A Minor ◽  
Minor Procedure ◽  
Time Point

Pediatric procedural sedation is required for a wide variety of interventions ranging from nonstimulating imaging procedures to painful minor surgeries and other tests. The measurement of how well a given sedation strategy has met the requirements for a procedure is not well codified by simply noting the depth of sedation provided. Patients may be deeply sedated but thrashing about during a painful procedure, and they may be almost awake and perfectly tolerating a minor procedure. Procedural sedation must be measured using a rubric that appreciates the “state” of the patient and qualifies his or her movement, stress, pain, and safety at any specific time point during the procedure. The ability to control these factors and provide an acceptable state for the patient and the proceduralist should be the standard for measuring the quality of sedation provision for children.

scholarly journals Transcriptome dynamics of the Myxococcus xanthus multicellular developmental program

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
José Muñoz-Dorado ◽  
Aurelio Moraleda-Muñoz ◽  
Francisco Javier Marcos-Torres ◽  
Francisco Javier Contreras-Moreno ◽  
Ana Belen Martin-Cuadrado ◽  
...  
Keyword(s):  
Myxococcus Xanthus ◽  
Developmental Cycle ◽  
Fruiting Bodies ◽  
Rna Seq ◽  
Specific Time ◽  
Future Studies ◽  
Developmental Program ◽  
Global View ◽  
Specific Time Point ◽  
Time Point

The bacterium Myxococcus xanthus exhibits a complex multicellular life cycle. In the presence of nutrients, cells prey cooperatively. Upon starvation, they enter a developmental cycle wherein cells aggregate to produce macroscopic fruiting bodies filled with resistant myxospores. We used RNA-Seq technology to examine the transcriptome of the 96 hr developmental program. These data revealed that 1415 genes were sequentially expressed in 10 discrete modules, with expression peaking during aggregation, in the transition from aggregation to sporulation, or during sporulation. Analysis of genes expressed at each specific time point provided insights as to how starving cells obtain energy and precursors necessary for assembly of fruiting bodies and into developmental production of secondary metabolites. This study offers the first global view of developmental transcriptional profiles and provides important tools and resources for future studies.

scholarly journals Levels of physical activity in four domains and affective wellbeing before and during the Covid-19 pandemic

2021 ◽  
Vol 79 (1) ◽  
Author(s):  
Eliane S. Engels ◽  
Michael Mutz ◽  
Yolanda Demetriou ◽  
Anne K. Reimers
Keyword(s):  
Mental Health ◽  
Physical Activity ◽  
Protective Factor ◽  
Total Sample ◽  
Poor Mental Health ◽  
German Population ◽  
Time Points ◽  
Sport And Exercise ◽  
Over Time ◽  
Time Point

Abstract Background Latest studies indicated that the general mental health level is low during the pandemic. Probably, this deterioration of the mental health situation is partly due to declines in physical activity. The aim of this study was to investigate differences in and the association between affective wellbeing and levels of different domains of physical activity at three time points before and during the pandemic. Method We used a nationwide online panel with a trend data design encompassing a total sample of N = 3517, representing the German population (> 14 years). Four different activity domains (sport and exercise, light outdoor activity, housework/gardening, active travel) and affective wellbeing (positive and negative affect) were assessed at three time points before and during the Covid-19 pandemic (October 2019, March 2020, October 2020). Results Multivariate analyses of variance (MANOVA) indicate differences regarding affective wellbeing over the three time points with the lowest values at the second time point. Levels of activity in the four domains differed significantly over time with the strongest decrease for sport and exercise from the first to the second time point. Partial correlations indicated that the relationships between sport and exercise and positive affect were most consistent over time. Conclusions Overall, our findings suggest that physical activity plays a particularly important role in the pandemic period as a protective factor against poor mental health. Especially sports and exercise seem to be supportive and should be encouraged, e.g. by providing additional support in finding adequate outdoor, home-based or digital substitutes.

scholarly journals Knee Muscle Strength Recovery in the Early Period After ACL Reconstruction

2014 ◽  
Vol 2 (11_suppl3) ◽  
pp. 2325967114S0014
Author(s):  
Gulcan Harput ◽  
Hasan Erkan Kılınc ◽  
Hamza Özer ◽  
Gül Baltacı ◽  
Carl G. Mattacola
Keyword(s):  
Acl Reconstruction ◽  
Early Period ◽  
Quadriceps Strength ◽  
Isometric Strength ◽  
Time Points ◽  
Hamstring Muscles ◽  
Significant Difference ◽  
Isometric Torque ◽  
Over Time ◽  
Time Point

Objectives: The aim of this study was to investigate quadriceps and hamstrings isometric strength at 4, 8 and 12 week time points following ACL Reconstruction (ACLR) and to document the strength changes of these muscles over time. The primary hypothesis was that there would be significant increases in quadriceps and hamstring muscle strengths between the 4th, 8th and 12th weeks following ACLR. The secondary hypothesis was that the quadriceps index would be higher than hamstring index at 12th week after ACLR. Methods: Thirty patients (Mean ± SD [age, 29.1±2.3yrs; weight, 77.3±13.2kg; height, 172.1±7.1cm; BMI, 21.2±3.5kg/m2, time to surgery: 7.1±7.2 months]) who underwent ACLR with Hamstring Tendon Autograft (HTG) were enrolled in this study. The isometric strength of quadriceps and hamstring muscles was measured on an isokinetic dynamometer at 60° knee flexion angle at 4th, 8th and 12th weeks after surgery. The recovery of quadriceps and hamstring muscles strength following rehabilitation was expressed as a Quadriceps Index (QI) and Hamstring Index (HI) and calculated with the following formula:[(maximum voluntary isometric torque of the involved limb / maximum voluntary isometric torque by uninvolved limb) × 100]. Torque output of the involved and uninvolved limbs and quadriceps and hamstring indexes were used for the statistical analysis. A repeated measures of ANOVA was used to determine the strength changes of quadriceps and hamstrings over time. Results: Quadriceps and Hamstrings strengths significantly increased over time for both involved (Quadriceps: F (2,46)=58.3, p<0.001, Hamstring: F (2,46)=35.7, p<0.001) and uninvolved limb (Quadriceps: F(2,46)=17.9, p<0.001, Hamstring: F(2,46)=56.9, p=0.001 ). Quadriceps strength was higher at 12th week when compared to the 8 and 4 week time points for the involved limb (p<0.001), and it was higher at 8th week when compared to 4 week time point for the involved limb (p<0.001). For the uninvolved limb, quadriceps strength was also higher at 12th week when compared to the 8 (p=0.02) and 4 week time point (p<0.001), and higher at 8 week when compared to the 4 week time point (p=0.02). Hamstring strength was higher at 12 week when compared to the 8 and 4 week time points (p<0.001) and it was higher at 8 week when compared to 4 week time point for the involved limb (p<0.001). For the uninvolved limb hamstring strength was also higher at 12 week when compared to 4 week time point (p=0.01). There was no significant difference between the 4 and 8 week time points (p>0.05) or between the 8 and 12 week time points (p=0.07). Quadriceps and hamstring indexes significantly changed from 4th weeks (QI:57.9, HI:54.4 ) to 8th weeks (QI:78.8, HI:69.9 ) and from 8th weeks to 12th weeks (QI:82, HI:75.7 ) (p<0.001); however, there was no difference between indexes at the 12-week time point (p=0.17). Conclusion: Isometric strength of quadriceps and hamstring muscles for the involved and uninvolved limb increased during the early period of ACLR. The results of this study could be a baseline for clinicians while prescribing a rehabilitation protocol for ACLR patients with HTG to better appreciate expected strength changes of the muscles in the early phase.

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