Speed Regime Research Articles

Design perspectives of a system identification approach of the NATO AVT-316 multi-swept wing aerodynamics

Air supremacy requires enhanced maneuvering capabilities at high angles of attack and even beyond the stall angle. High angle-of-attack (high-α) maneuverability can be achieved using swept wings and tailored leading-edge shapes to replace local and disorganized flow separation with controlled separation-induced leading-edge vortices (LEV). Strong leading-edge vortices delay the stall to higher angles and generate a non-linear lift increment up to the angle of attack where the jet-type flow structure of LEV changes to a reversed-flow bubble (vortex breakdown phenomenon). A multi-swept wing configuration has the potential to delay the vortex breakdown to even higher angles as the vortices formed over the front wing can energize vortices formed over the main wing and lead to vortex merging. This article is focused on understanding the unsteady interactions between multiple leading edge vortices formed over multi-swept wing configurations in the subsonic speed regime. Specifically, this article investigates the aerodynamic characteristics of wings being evaluated under the initiative of the NATO STO AVT-316 Task Group. Highly refined meshes, and the use of hybrid turbulence models such as Detached Eddy Simulations (DES) and Delayed DES are required to accurately resolve the vortical flows over these wings. Simulating all flow conditions of interest is a computationally expensive approach. A system identification method was therefore proposed to rapidly and accurately generate aerodynamic models of these wings. The method uses a novel piece-wise chirp (constant amplitude and increasing frequency) motion as an input signal (training maneuver). The motion computational cost is equivalent to the cost of six static CFD simulations, however it can predict aerodynamic responses of the wings over a wide range of angles of attack. The method has been tested for double and triple delta wings. Some design considerations are provided based on predicted flow features and aerodynamic data. Prediction results with different turbulence models, sting geometries, grid resolutions and an adaptive mesh refinement approach are provided.

Flux Rope Modeling of the 2022 September 5 Coronal Mass Ejection Observed by Parker Solar Probe and Solar Orbiter from 0.07 to 0.69 au

As both Parker Solar Probe (PSP) and Solar Orbiter (SolO) reach heliocentric distances closer to the Sun, they present an exciting opportunity to study the structure of coronal mass ejections (CMEs) in the inner heliosphere. We present an analysis of the global flux rope structure of the 2022 September 5 CME event that impacted PSP at a heliocentric distance of only 0.07 au and SolO at 0.69 au. We compare in situ measurements at PSP and SolO to determine global and local expansion measures, finding a good agreement between magnetic field relationships with heliocentric distance, but significant differences with respect to flux rope size. We use PSP/Wide-Field Imager for Solar Probe images as input to the ELlipse Evolution model based on Heliospheric Imager data (or ELEvoHI), providing a direct link between remote and in situ observations; we find a large discrepancy between the resulting modeled arrival times, suggesting that the underlying model assumptions may not be suitable when using data obtained close to the Sun, where the drag regime is markedly different in comparison to larger heliocentric distances. Finally, we fit the SolO's magnetometer and PSP's FIELDS data independently with the 3D Coronal ROpe Ejection (or 3DCORE) model, and find that many parameters are consistent between spacecraft. However, challenges are apparent when reconstructing a global 3D structure that aligns with arrival times at PSP and SolO, likely due to the large radial and longitudinal separations between spacecraft. From our model results, it is clear the solar wind background speed and drag regime strongly affect the modeled expansion and propagation of CMEs and need to be taken into consideration.

Comparison of Model Predictive Control Algorithms Based on Different Reference Models

<div>Model predictive control (MPC) plays a crucial role in advancing intelligent vehicle technologies. Controllers designed based on various vehicle reference models, including kinematic and dynamic models (both linear and nonlinear), often demonstrate significant differences in control performance. This study contributes by comparing three different MPC control methods and proposing a comprehensive evaluation criterion that considers tracking accuracy, stability, and computational efficiency across various MPC designs. Joint simulations using CarSim and MATLAB/Simulink reveal distinct performance characteristics among the MPC variants. Specifically, kinematic MPC (KMPC) exhibits superior performance at low speeds, linear model predictive control (LMPC) performs best at moderate speeds, and nonlinear MPC (NMPC) achieves optimal performance at high speeds. These findings highlight the adaptive nature of MPC strategies to varying vehicle dynamics and operational conditions, emphasizing the importance of selecting the appropriate MPC design based on the speed regime for maximizing control effectiveness in intelligent vehicles.</div>

An Antiferromagnetic Neuromorphic Memory Based on Perpendicularly Magnetized CoO.

Antiferromagnets (AFMs) are ideal materials to boost neuromorphic computing toward the ultrahigh speed and ultracompact integration regime. However, developing a suitable AFM neuromorphic memory remains an aspirational but challenging goal. In this work, we construct such a memory based on the CoO/Pt heterostructure, in which the collinear insulating AFM CoO shows a strong perpendicular anisotropy facilitating its electrical readout and writing. Utilizing the unique nonlinear response and bipolar fading memory properties of the device, we demonstrate a multidimensional reservoir computing beyond the traditional binary paradigm. These results are expected to pave the way toward next-generation fast and massive neuromorphic computing.

A fully coupled Pressure-Based method for compressible flows at all Mach numbers

When extending the fully coupled pressure-based method to resolve compressible flows, the effective treatment of the boundary conditions is crucial due to the inherent characteristics of compressible flows. Failure to properly account for this can result in numerical instability and divergence. In this article, a detailed treatment of boundary conditions for compressible flows has been formulated in terms of the boundary face’s contribution to the discretization equation of the boundary element. These boundary conditions involve subsonic inlet, supersonic inlet, subsonic outlet, and supersonic outlet boundary conditions. The analysis has been focused on test cases of flow through a bumped arc channel and a converging–diverging nozzle including quasi-incompressible, subsonic, transonic, supersonic and hypersonic speed regimes, where the Mach number ranges from 0.1 to 10. The results indicate the robust performance of the fully coupled method in resolving compressible flows. The computational results obtained from the fully coupled algorithm exhibit a high degree of consistency with available literature cases and analytical solutions, with a maximum error of less than 5%. Moreover, the findings also suggest that the coupled solver presents promising potential in handling hypersonic flows.

Observer based pitch control for load mitigation and power regulation of floating offshore wind turbines

Abstract Most commercial wind turbines use proportional-integral (PI) collective blade-pitch control to regulate rotor speed in the above-rated wind speed regime. A significant drawback of this type of controller is that it assumes that the blades have identical structural properties and are subject to similar aerodynamic loads, which is seldom the case. Also, these controllers are designed to regulate the rotor speed and are not designed for structural vibration/load reduction. However, it is well known that blade pitch control can reduce structural loads on wind turbines. This opens up the possibility of designing controllers that use existing actuators and sensors like the blade pitch actuators to reduce structural loads/vibrations while maintaining the required rotor speed. Recent studies have investigated individual blade pitch control (IPC) to address these shortcomings. However, the vast majority of studies published in the literature depend on the availability of state measurement. Although sensors are commonly placed on all wind turbines, and some information is readily available, the measurement required by the typical state-feedback controllers is usually not available. Displacements and velocities of the blade, the tower and the floating platform are difficult to measure. This paper develops an observer-based individual blade pitch controller for load mitigation and power regulation of floating offshore wind turbines. We propose to use a Kalman filter to estimate the state from the accelerometer and strain gauge measurement for use in the state-feedback controller. The state-feedback controller was proposed previously by the authors that showed excellent performance. This paper extends the capability of the state-feedback controller by designing an observer (Kalman filter) to estimate the state from limited measurements. The proposed observer based controller is compared against a baseline proportional integral collective blade pitch controller and full state-feedback controllers to evaluate its performance. Numerical results show that the proposed output feedback controller offers performance improvements over the baseline controller, similar to the full state-feedback controller.

Model for Calculating Stress Intensity Factors for an Inclined Crack at the Leading Edge of a Gas Turbine Engine Blade Under the Influence of Centrifugal Forces

The study is devoted to the issue of the destruction of a body with an inclined crack during rotation. A mathematical model for calculating stress intensity factors in a rectangular plate with an inclined crack under the influence of centrifugal tensile forces during rotation around an axis lying in the plane of the plate is constructed in the article. Based on the equations of the theory of elasticity and the principles of brittle fracture mechanics, relationships were obtained that relate the stress intensity factors of type I and II, the rotation speed and geometry of the plate, as well as the parameters of the crack: length, angle of inclination to the axis of rotation, distance from the axis of rotation to the crack. The complexity of the study is because the plate in question with an inclined crack is under the action of mass forces. Therefore, the values of the effective stresses are not the same along the crack edge. Accordingly, stress intensity factors will depend on the location of the crack relative to the axis of rotation. The influence of the crack location and plate rotation speed on the change in stress intensity factor values is analyzed based on the results obtained. As the distance from the axis of rotation to the crack increases, the values of the stress intensity factors decrease. As the plate rotation frequency increases, the stress intensity coefficients increase according to a parabolic law. The results of the study can be used to assess the limit state of the rotating blades of a gas turbine engine in the presence of an inclined crack. The mathematical model can find practical application for assessing the critical speed regime of blade rotation in the presence of cracks of various lengths and angles of inclination to the rotation axis.

For whom is sharing really scaring? capturing unobserved heterogeneity in perceived comfort when cycling in shared spaces

Shared spaces for active mobility prioritize the safety and comfort of vulnerable road users by segregating them from motorized vehicles. However, the diverse speed regimes of pedestrians and cyclists can lead to encounters that may affect their comfort. In addition, the very perception of comfort may vary across individuals depending on their demographics, and therefore the determinants of comfort and their effects may not be fixed across all individuals. Despite these complexities, there is limited research in understanding the heterogeneous interactions between cyclists and other road users in shared spaces. To bridge this gap, we conducted an intercept survey complemented by an experimental section involving 594 cyclists in Sweden. This study focuses on gaining insights into cyclists' experiences, particularly their comfort levels during 'passing' and 'meeting' events with other road users in shared spaces. We then used the collected data to develop a random effect latent class ordered probit model to scrutinize the determinants of cycling comfort in passing and meeting scenarios. The latent class specification is employed to account for unobserved heterogeneity in the data. Findings reveal that female cyclists generally perceive less comfort compared to their male counterparts in both scenarios. Passing events have a more negative impact on older adults, leading to less comfort compared to younger cyclists. We also found that previous cycling experience increases comfort in shared facilities, particularly for older adults. These results highlight the intricate nature of perceived comfort in interactions, particularly concerning demographic characteristics, contributing to the promotion of user diversity in shared spaces.

ANALYSIS OF FACTORS AFFECTING DRIVING IN THE DARK TIME OF DAY

An analysis of factors affecting road traffic safety from the point of view of driving a car in the dark was carried out, in particular, the technical condition of the car, tinting of the windows, lighting of the streets (roads), speed of movement, driver fatigue. It has been established that a significant number of factors require significantly greater concentration and esponsibility from drivers. Driving a car in the dark requires special knowledge, skills and attention. The technical condition of vehicles becomes a number of priority problems. Vehicle malfunctions that are not detected in time or not eliminated increase the likelihood of a Road Traffic Accident. The cause of a Road Traffic Accident, especially in the dark period of the day, may be insufficient visibility of the road situation by the driver, which is caused by the violation of the requirements for tinting the glass in the car. The driver will not be able to fully assess everything that happens on the road at night both in conditions of insufficient visibility and in the presence of bad weather conditions. At the same time, proper street lighting can help reduce the risk of road traffic accidents by improving pedestrian visibility, reducing the likelihood of accidents and providing safer road conditions for both drivers and pedestrians. Speeding and incorrect selection of the speed regime in specific traffic conditions is one of the main factors affecting both the number and severity of Road Traffic Accidents. Another reason for the occurrence of a Road Transport Accident may be the driver’s fatigue, which reduces his concentration and ability to drive safely.

Elaboration of a Generalized Mixed Model for the wind speed distribution and an assessment of wind energy in Algerian Coastal regions and at the Capes

Understanding and evaluating wind energy involves various steps, including the observed temporal and directional variations in wind speed, choosing a suitable Probability Density Function (PDF) to describe wind regimes, and selecting an appropriate location for building wind farms. The wind speed data archived from nine meteorological stations along the northern coast of Algeria from 2017 to 2021 was used as a dataset to achieve these purposes. Zero-inflated mixed model (ZIMM) has been elaborated to model the wind speed regimes that combine two processes. The first process consists of mixing two PDFs that generate the counts data. The second process generates the residual zero-counts data. The estimation of ZIMM parameters is obtained with the Expectation–Maximization algorithm. ZIMM performances were evaluated at the selected sites using the commonly used goodness of fit (GOF) metrics: coefficient of determination (R2), root mean square error (RMSE), sum of square error (SSE), Kolmogorov–Smirnov (KS), Akaike information criterion (AIK), Bayesian Information Criterion (BIC), and compared with the widespread single PDFs: the two parameters Weibull, generalized extreme value (GEV) and Normal–Weibull mixed model. The datasets are used as input for assessing wind power and the feasibility of wind power plants in 24 Algerian Capes where the data is unavailable, using the Wind Atlas Analyses and Application Program (WAsP) and three different wind turbines, namely Nordex N50, Bonus B54, and Nordex N60. The results show significant variations in diurnal, monthly, and seasonal mean wind speed and power density. According to all GOF, the ZIMM PDF model outperforms conventional PDFs and the mixed model at the nine meteorological stations. The Bonus B54 wind turbine has the best capacity factor (Cp) with the lowest electrical production cost of all Algerian Capes, and the Cp exceeds 0.3 at 15 Capes from the 24 analyzed Capes. The highest Cp, about 0.467 with an annual electric production that reaches 4.09 GWh/year, is obtained at Cape Takouch with the lowest electrical production cost of 0.0414 $/kWh and 2.032 Kton/year of CO2 emission avoided.

Detection and Diagnostics of Bearing and Gear Fault under Variable Speed and Load Conditions Using Heterogeneous Signals

In industrial applications, rotating machines operate under real-time variable speed and load regimes. In the presence of faults, the degradation of critical components is accelerated significantly. Therefore, robust monitoring algorithms able to identify these faults become crucial. In the literature, it is hard to find comprehensive monitoring systems that include variable speed and load regimes with combined gearbox faults using electrical and vibration signals. For this purpose, a novel signal processing methodology including a geometric classification technique is proposed. This methodology is based on using different types of sensors such as current, voltage and vibration sensors with a regime normalization, which allows the grouping of different regimes belonging to the same health state. It consists of reducing dispersion between the class observations and separating other classes representing different health states including the variation in speed and load. Then, a peripheral threshold is proposed in our classifier to diagnose new health states. To verify the effectiveness of the methodology, current, voltage and vibration data from a gearbox system are collected under variable speed and load levels.

Suppression of spiking defects in deep penetration electron beam welded ETP copper

The electron beam is an appropriate tool to weld pure copper due to its high absorptivity on the copper surface, a high power density and inert vacuum environment. However, deep penetration electron beam welding of pure copper often produces the spiking defect. In this work bead on plate electron beam welding was done on Cu-ETP. A critical welding speed was determined for the distinction between a conduction-determined (at lower welding speed) and a non-conduction-determined welding speed range (at higher welding speed). The influence of high preheating temperatures was shown. The welds were investigated by light optical microscopy, electron backscatter diffraction measurements, ultrasonic testing, in situ thermal imaging, electrical resistance measurements and tensile tests. It was shown that in the conduction-determined welding speed regime without preheating, full and partial penetration welds exhibited root porosity. This effect was related to the overheating of the weld pool in combination with the phenomena causing spiking. Low defect root formation was achieved by using welding speeds greater than the critical value or by applying high preheating temperatures. The joints reached up to 98% of the international annealed copper standard in terms of specific electrical conductivity. Rupture took place within the joints during tensile tests. The joints exhibited up to 77% of the ultimate tensile strength of the base metal. Welds carried out with preheating exceeded the base metal regarding the fracture strain.

До аналізу викидів від зносу автомобільних шин, як екологічної складової використання автомобільного транспорту

In the work, a study of the negative impact of vehicles on the environment, namely emissions from the wear of automobile tires, was carried out. As a result, tire dust is released into the environment, which settles on the roads, or gets into the air and is carried over considerable distances. The research of European and American scientists on the wear and tear of vehicle tires during their movement and the harmfulness of these emissions to human health is analyzed. The mechanism of tire tread wear has been studied, its types have been determined, and the factors affecting wear of the tire tread have been determined. Based on the analysis of scientific research, the influence of the established factors on the change in the concentration of PM10 and PM2.5 solid particles in emissions from car tire wear was determined. It was found that an aggressive driving style contributes to a significant increase (by 78 times) in the concentration of solid particles in emissions during tire wear. An increase in the level of emissions is also influenced by an increase in the load on the tires and an increase in the speed of movement. It was determined that new car tires are characterized by an increase in the concentration of particulate emissions, which is explained by a certain period of their running-in. An increase in the concentration of solid particles was also established when using studded winter tires compared to non-studded and summer ones. Possible steps for deepening research on the problem of solid particle emissions from tire wear and their impact on the environment are proposed. Among them: clear compliance with the load index when choosing tires, compliance with speed regimes, ensuring compliance of tire materials with wear resistance standards, taking into account the specifics of the impact of materials and the limit sizes of their components on the wear of automobile tires when designing coatings for new automobile roads and modernization of existing ones.

Patterns of the noise level change at different speeds for mixed traffic flows

The study describes the problems of determining the normative levels of traffic noise on city main streets. The main statements and preliminary laws that are taken into account when determining the acoustic characteristics of the urban environment in the current building regulations are considered. It was established that the main factor that determines the acoustic load on city streets is the type of covering. The dynamics of the level of traffic noise of mixed flows, taking into account different types of coverage at different speed regimes, are also determined. The obtained results partially differ from the calculated values, and therefore are relevant for the development of modern norms and rules for the calculation of traffic noise on city highways.

An exploration of the super-critical speed dynamic behaviours of the pantograph-catenary system

The train operating speed is traditionally limited to lower than 0.7 times the critical speed of the catenary. The material’s strength limits the tensile forces of the tension wires, preventing the further improvement of the train speed. A novel super-critical speed operating strategy of the pantograph catenary system (PCS) is proposed, using the relatively low tensile values of the catenary to make the pantograph run at a speed ratio larger than 1. The analytical results of a string under a moving load show the theoretical possibility of the super-critical speed operating strategy in moving load problems. The finite element method (FEM) is adopted for the model of the catenary. The differences between the simple catenary and the stitched catenary running at the super-critical speed regime are compared. Then, the tensile forces designation of the stitched catenary with different speed ratio values beyond 400 km/h is studied. Finally, the dynamic behaviours of the PCS reaching the super-critical speed regime are discussed, consisting of the continuous acceleration process and the transition process from the high-tension section to the low-tension section. The proposed super-critical speed operating strategy may be promising for the next-generation high-speed PCS.

On the Efficacy of Monin–Obukhov and Bulk Richardson Surface-Layer Parameterizations over Drylands

Abstract Surface-layer parameterizations for heat, mass, momentum, and turbulence exchange are a critical component of the land surface models (LSMs) used in weather prediction and climate models. Although formulations derived from Monin–Obukhov similarity theory (MOST) have long been used, bulk Richardson (Rib) parameterizations have recently been suggested as a MOST alternative but have been evaluated over a limited number of land-cover and climate types. Examining the parameterizations’ applicability over other regions, particularly drylands that cover approximately 41% of terrestrial land surfaces, is a critical step toward implementing the parameterizations into LSMs. One year (1 January–31 December 2018) of eddy covariance measurements from a 10-m tower in southeastern Arizona and a 200-m tower in western Texas were used to determine how well the Rib parameterizations for friction velocity (), sensible heat flux (H), and turbulent kinetic energy (TKE) compare against MOST-derived parameterizations of these quantities. Independent of stability, wind speed regime, and season, the Rib and TKE parameterizations performed better than the MOST parameterizations, whereas MOST better represented H. Observations from the 200-m tower indicated that the parameterizations’ performance degraded as a function of height above ground. Overall, the Rib parameterizations revealed promising results, confirming better performance than traditional MOST relationships for kinematic (i.e., ) and turbulence (i.e., TKE) quantities, although caution is needed when applying the Rib H parameterizations to drylands. These findings represent an important milestone for the applicability of Rib parameterizations, given the large fraction of Earth’s surface covered by drylands. Significance Statement Weather forecasting models rely upon complex mathematical relationships to predict temperature, wind, and moisture. Monin–Obukhov similarity theory (MOST) has long been used to forecast these quantities near the land surface, even though MOST’s limitations are well known in the scientific community. Researchers have suggested an alternative to MOST called the bulk Richardson (Rib) approach. To allow for the Rib approach to be used in weather forecasting models, the approach needs to be tested over different land-cover and climate types. In this study, we applied the Rib approach to dry areas of the United States and found that the approach better represented turbulence variables than MOST relationships. These findings are an important step toward using Rib relationships in weather forecasting models.

Plane wave stability analysis of Hartree and quantum dissipative systems

We investigate the stability of plane wave solutions of equations describing quantum particles interacting with a complex environment. The models take the form of PDE systems with a non local (in space or in space and time) self-consistent potential; such a coupling lead to challenging issues compared to the usual nonlinear Schrödinger equations. The analysis relies on the identification of suitable Hamiltonian structures and Lyapounov functionals. We point out analogies and differences between the original model, involving a coupling with a wave equation, and its asymptotic counterpart obtained in the large wave speed regime. In particular, while the analogies provide interesting intuitions, our analysis shows that it is illusory to obtain results on the former based on a perturbative analysis from the latter.

An analytical study of the climatic elements in Bazian region - Sulaymaniyah for the period from 1985 - 2022 and its impact on the planting dates of some crops

During a field study in Bazian Plain which is one of the most important agricultural areas in Sulaymaniyah it became clear that current scenario is linked to rapid climate change directly. Arid and semi-arid ecosystems are likely to be particularly affected by changes in wind speed and vapour pressure regimes, changes in those regimes may show from climate data that vapour pressure has clearly increased during these years. For instance, in January and February of 2017 wind speed reached 8 and 9 (m. sec.-1). Sulaymaniyah Meteorology Department reported a lesser speed of 0.1 (m. sec.-1) in the months 4, 5, 6 and 9, on average the greatest rates of 3.1 and 2.2 (m. sec.-1) in 1985 and 1992. on the other hand, in 1991 recorded the lowest rate of (1 m. sec.-1) amounts and times of precipitation during the study years, floods occurred in some seasons the dry seasons less than 300 (ml) were very few, while the remaining seasons were more than 450 (ml) rainfall amounts in the seasons 2006-2007, 2007-2008 and 2008-2009 were among the driest seasons during the years of the study Which was straight (66000, 87000, 86000) dunam. as the agricultural areas were reduced to their lowest levels, although the levels of precipitation were acceptable. The data gathered found that the average annual temperature rate has increased by over 1.3(°C) with the warmest year for this time being recorded in 2010 at 21.55(°C). Sunshine was the lowest in terms of the number of daylight hours in December with total annual averages for the period 1985-2022 for December being 184.4 (hours) 1996 was the lowest with 2.3 (hr.) and 2018 was also the second lowest with a value of 3.3 (hr.) During the decades of the study period, wheat growing seasons advanced mostly to November, and in recent decades (2011-2020) (2010-2009) 20 farmers plant in December to ensure rainfall.

ASSESSMENT OF THE UNEVENNESS OF THE MOVEMENT OF VEHICLES IN THE PLACES OF SEPARATION OF TRAFFIC FLOWS

The movement of vehicles in the places of separation of traffic flows is analyzed. The high-speed mode of movement of vehicles along traffic lanes at a regulated intersection in the places of traffic flow separation has been determined. It is recorded that the number of formed “bundles” increases in the places of separation of transport flows. The movement of the formed “packs” of moving cars determines the speed mode of vehicles. The experiment showed that the speed of movement along the lanes is different. In a lane with a large number of formed “bundles”, the speed of cars is less than in a lane with a smaller number of “bundles”. It is established that the presence of “bundles”, especially in the areas of separation of traffic flows, leads to a large variation in the range of changes in the speed of vehicles at the intersection. The highest value of the speed mode of vehicles when driving on the experimental section is within 15-20 km/h, and the lowest is less than 5 km/h.
 Purpose – determination of the factors influencing the change in the speed regime of vehicles in the places of separation of traffic flows.
 Methodology statistical methods of processing a full-scale experiment were used in the work.
 Results: the ranges of changes in the speed of vehicles in places where traffic flows are separated by lanes and the reasons for their changes are determined.
 Practical implications: the obtained results should be used in the development of measures to ensure road safety in places of separation of traffic flows and the organization of traffic at intersections.

Дослідження показників якості організації дорожнього руху в умовах міста методом GPS-треків

The choice of rational quality criteria for the organization of road traffic in cities is an urgent task for scientists in the field of road transport, as it directly affects the effectiveness of activities in the field of ensuring the safety and comfort of car traffic in urban conditions. Depending on the goals of the analysis, the complexity of the network, and technical capabilities, the quality of traffic management can be assessed by indicators of the economic efficiency of the transport process, the level of accidents, environmental safety, social attractiveness, etc. The modern level of development of geo-information technologies allows for constant monitoring of the vehicle's speed mode. To obtain characteristics of the quality of traffic organization, experimental studies were conducted on a section of the street-road network of the city of Kharkiv, which corresponds to a typical route of personal transport from a remote sleeping area to the central part of the city.
 As a result of data processing of the GPS track, a histogram of the distribution of instantaneous speed and graphs of the car’s movement in the coordinates “time-distance”, “time-speed”, "distance-speed” were built, which allow you to visually assess the mode of movement along the entire route and determine potential "bottlenecks". Such spatio-temporal characteristics as average technical speed, specific time in motion, specific idle time, as well as energy indicators of the quality of traffic management were also calculated: acceleration noise, speed gradient, energy gradient. After dividing the experimental route into separate kilometer sections, changes in the characteristics of the quality of traffic organization, as it approached the city center, were analyzed. On the first half of the route, when moving along the main street, the instability of the speed regime was observed due to stops and idling in the zone of regulated intersections. The presence of a trend towards a decrease in the average technical speed when approaching the city center is explained by an increase in the loading of VDM within the central business part of the city and, as a result, the appearance of additional traffic delays. As we approached the city center, the specific time in motion increased with a slight increase in the specific idle time, and an increase in the speed gradient was also observed with a slight decrease in the energy gradient.