Analysis of the Effect of the Speed Factor on Highway Safety Using the Machine Learning Method

Speed is one of the most important factors that can significantly change the severity of accidents. Providing a model with predictive factors leads to designing traffic plans to promote safety. This study aims to create statistical models for accidents occurred on Firuzkuh highway, Iran. Moreover, the probability of each type of accident was determined using the logit model. Various modeling methods, such as backward, forward, and entering methods, were evaluated to find the best method. Finally, since the backward method had the best performance in terms of R2 and goodness of fit, the logit model of accidents was created. According to the model, the independent variables of the 12-24 hours, rainy weather, a speed of 81-95 and 96-110 km/h, the lack of attention ahead and the Pride brand of vehicle increased the severity of accidents, while the variables with negative coefficients of Tuesdays, the summer and spring seasons, sunny weather, a male driver, and daylight, reduced the severity of accidents.

Individual Factorial Structure of Biomechanical and Psychophysiological Indicators as a Basis for Determining the Fighting Style of Qualified Veteran Boxers

Purpose: to reveal the fighting style of veteran boxers based on the individual factor structure of psychophysiological and biomechanical indicators. Material and methods. The study involved 42 qualified veteran boxers (aged 45-50). A biomechanical analysis of the indicators of the movement speed of various points and the values ​​of the joint angles while performing a direct blow by boxers has been used as a research method. The psychophysiological method has been used to determine the time of a simple and complex reaction under standard conditions and in various testing modes. Descriptive Statistics and Factor Analysis have been applied as methods of statistical analysis. Results. Two main factors have been identified in the structure of the complex performance of qualified veteran boxers,. Factor 1 (55.063% of the total aggregate variance) is named "Speed". Factor 2 (44.937% of the total aggregate variance) stands for “Speed ​​Endurance”. Individual factor structure, which is characterized by the distinctive factor "Speed ​​and Coordination Endurance" by more than 80% as well as by the marked factor "Speed" by less than 30% is considered to be a particularity of the tempo style boxers. Individual factor structure, which is characterized by the intensity of the factor "Speed" by more than 80%, and by the distinctive factor "Speed ​​and Coordination Endurance" by less than 30% is considered to be typical for the playing style boxers. The individual factor structure, which is characterized by the marked factor "Speed" by more than 50%, and by the intencity of the factor "Speed ​​and Coordination Endurance" by less than 30% is seen to be peculiar to the strength style boxers. Conclusions. It is shown that the psychophysiological features of boxers of different fighting styles are reflected in the features of the direct strike technique. The lack of speed at the beginning of the movement in tempo style boxers is supplemented and compensated by the high speed of movement. Playing style boxers are characterized by a high speed of movement at the very beginning of the strike. Strength style boxers are characterized by the gradual development of movement speed.

Effect of the Speed Factor On the Amplitude of the Blade Passing Frequency in the Vaneless Space of a Pump Turbine in Turbine Mode

An exponential expression describing the relationship between the amplitude of the blade passing frequency in the vaneless space of a pump turbine operating in the turbine mode and the speed factor is proposed based on statistical analysis. This mathematical relationship was discovered through signal processing of the data recorded during the emergency load rejection process of a prototype pump turbine. Subsequently, based on the pumped-storage test rig at Wuhan University, an experimental investigation was conducted to verify this mathematical relationship. The results indicated that, under the optimal guide vane opening of the model pump turbine, the goodness of fit of this mathematical relationship was quite high. As for the Francis pump turbine, the speed factor corresponds to the Strouhal number. Therefore, for this correlation, the underlying physical mechanism is the influence of the Strouhal number. This relation could inform the design and operation of pump turbines to control the intensity of pressure pulsations in the vaneless space. In addition, based on this mathematical relationship, the intensity of the rotor-stator interaction for different pump turbines can be compared quantitively.

Speed factor in the road safety system

The article examines various factors affecting the accident rate in road transport and studies in detail the consequences of exceeding the established speed limit. Based on the statistics of road accidents and calculations made, the level and severity of the consequences caused by the violation of the speed limit by the driver is established.

STUDY OF THE INFLUENCE OF FREIGHT TRANSPORT TECHNOLOGY ON TRAFFIC SCHEDULE ON MACRO INDICATORS OF THE RAILWAY SYSTEM OF UKRAINE

The article examines the influence of freight transportation technology on special conditions according to the schedule of route trains on the quantitative and qualitative indicators of the operational work of the railway system of Ukraine. The calculations of the components of the freight car turnover are carried out. It was found that the strategy of routing, transportation by RRMP and coordination of loading and unloading terms significantly reduced the downtime of the car under freight operations. The analysis of indicators shows that the implemented technology of cargo transportation according to the RRMP allowed in 2019 to achieve a reduction within the busy flight of the number of technical stations from five stations in 2018 to 4.7 in 2019. The comparative analysis of technical and district speed is carried out and the speed coefficient is calculated. According to the analysis of the change in the speed factor, it can be stated that the ratio of precinct to technical speed remained unchanged in 2019 compared to 2018, which may indicate the lack of impact of transportation technology on dispatching, which was essentially unchanged for two years. Simulation according to the analytical approach of change of turnover of a freight car at increase in a share of transportations of freights under contracts on special conditions is executed. Calculations prove that with the increase of the share of cars of the working fleet, organized in the transportation of goods by RRMP in the element of car turnover - simple car at technical stations, can significantly reduce the overall turnover of the car. The influence of the technology of transportation according to the schedule on the reduction of the most significant element in the turnover of the car - the downtime of the car under freight operations.

Comparison between handwritten word and speech record in real-time using CNN architectures

This paper presents the development of a system of comparison between words spoken and written by means of deep learning techniques. There are used 10 words acquired by means of an audio function and, these same words, are written by hand and acquired by a webcam, in such a way as to verify if the two data match and show whether or not it is the required word. For this, 2 different CNN architectures were used for each function, where for voice recognition, a suitable CNN was used to identify complete words by means of their features obtained with mel frequency cepstral coefficients, while for handwriting, a faster R-CNN was used, so that it both locates and identifies the captured word. To implement the system, an easy-to-use graphical interface was developed, which unites the two neural networks for its operation. With this, tests were performed in real-time, obtaining a general accuracy of 95.24%, allowing showing the good performance of the implemented system, adding the response speed factor, being less than 200 ms in making the comparison.

Hydrodynamic analysis of a low head prototype Francis turbine for establishing an optimum operating regime using CFD

Hydraulic turbines need to operate at regimes other than designed ones. Off-design functioning of these turbines yields an inefficient and uneconomical operation of hydro projects. Performance and energy losses at different possible operating conditions need to be evaluated before finalizing the design of water turbines for satisfactory operations. Moreover, hydraulic turbines are unique machines designed for unique set of operating conditions and cost a huge percentage of the overall cost of the project. This work is compiled with twofold objectives; derivation of complete performance characteristics of a 48m head prototype Francis turbine in order to establish an optimum operating regime and, determination and analyses of head loss at different components of the turbine. Steady state flow simulations for four different load operations (60%, 80%, 100% and 120%) have been carried out using computational fluid dynamics. It is found that the optimum regime of operation lies within the speed factor range of 0.412-0.48 along with discharge factor range of 0.27-0.329 and maximum efficiency is obtained as 90.64% at full load operation. Maximum head loss in critical components of the turbine such as runner and draft tube is found as 12.7% at speed factor of 0.568 and 26.31% at 0.202 speed factor respectively. Also, the maximum total head loss in all the components is found as 47.8% at 60% load and 0.609 speed factor. It is concluded that the functioning of the turbine at higher speed factors is more detrimental than that at lower speed factors. Requirement of performance improvement at off-design conditions (especially at 60% load operation) is also suggested in order to widen the range of optimum operating regime. Obtained computational results are validated with experimental results and a strong agreement is found between the two.

Observed Physical Function Is Associated With Better Cognition Among Elderly Adults: The Adventist Health Study-2

Lifestyle factors may individually protect against the development of mild cognitive impairment. We investigate the relationships between both self-reported physical activity and measured physical function with cognition in a population of elderly adults, more than half of whom follow vegetarian dietary patterns. Otherwise healthy adults (n = 127, mean age 74.9 ± 7.9 years, 61.3% current vegetarians) were assessed using a comprehensive neuropsychological battery. A principal components analysis derived processing speed, executive function, and memory/language factors. Participants reported current levels of vigorous physical activity on questionnaires, and physical function and mobility were measured with the Physical Performance Test (PPT) and Timed Up and Go (TUG) Test. Generalized linear models estimated β coefficients for cross-sectional associations between cognitive factors and indicators of physical abilities and self-reported physical activity. Better physical function indicated by PPT was associated with higher scores on the processing speed factor (β = 0.21 SDs for each 4.4-point increase in PPT score; p = 0.02). Faster TUG times were also associated with higher processing speed factor scores (β = 0.21 SDs increase for each 2.8 second less TUG time; p = 0.02). Self-reported levels of vigorous physical activity were not associated with any area of cognitive function; the association between PPT, TUG and processing speed was independent of physical activity. Associations between PPT and TUG and processing speed were stronger among participants who followed vegetarian dietary patterns. Better physical function may have an effect on cognition in a context of healthy lifestyles.

Does Speededness in Collecting Reasoning Data Lead to a Speed Factor?

The consequences of speeded testing for the structure and validity of a numerical reasoning scale (NRS) were investigated. Confirmatory factor models including an additional factor for representing working speed and models without such a representation were employed for investigating reasoning data collected in speeded paper-and-pencil testing and in only slightly speeded testing. For achieving a complete account of the data, the models also accounted for the item-position effect. The results revealed the factor representing working speed as essential for achieving a good fit in data originating from speeded testing. The reasoning factors based on data due to speeded and slightly speeded testing showed a high correlation among each other. The factor representing working speed was independent of the other factors derived from reasoning data but related to an external score representing processing speed.