Real-Time LIDAR-Based Urban Road and Sidewalk Detection for Autonomous Vehicles

Road and sidewalk detection in urban scenarios is a challenging task because of the road imperfections and high sensor data bandwidth. Traditional free space and ground filter algorithms are not sensitive enough for small height differences. Camera-based or sensor-fusion solutions are widely used to classify drivable road from sidewalk or pavement. A LIDAR sensor contains all the necessary information from which the feature extraction can be done. Therefore, this paper focuses on LIDAR-based feature extraction. For road and sidewalk detection, the current paper presents a real-time (20 Hz+) solution. This solution can also be used for local path planning. Sidewalk edge detection is the combination of three algorithms working parallelly. To validate the result, the de facto standard benchmark dataset, KITTI, was used alongside our measurements. The data and the source code to reproduce the results are shared publicly on our GitHub repository.

Study of lifting platforms using three-dimensional computer-aided modeling

In the modern world, an aerial platform (auto-hydraulic lift) is an integral part of a rich model range of special crane equipment. The first primitive lift consisted of a lever, hinged on the base. A traction rope was placed on one side of the lever, and a counterweight on the other. With the help of his own physical strength, a person was able to rise to a small height using such a simple lifting mechanism. Currently, many types of lifts are used, which differ in height characteristics and the design of the lifting mechanism. Goal. The aim of this work is to study the kinematics of the moving elements of a hydraulic lift using a virtual model created on the basis of the Autodesk Inventor Professional software package. The model is based on an existing physical object. To study the kinematics of individual units and the installation as a whole, we use the method of modeling individual units and units of a machine, collecting them into a single mechanism with the task of all possible movements of structural elements in the Inventor package. Methodology. The assigned tasks can be solved by special design tools that are included in the software product, namely the environment for dynamic modeling, stress analysis. These tools are accessed while working in the "Assembly" environment, using the ribbon tabs "Design" and "Environments". The results of further research will bepresented in future publications.

Natural regeneration features of broad-leaved species under the canopy of coniferous stands in forest-steppe conditions

The age structure of the undergrowth was studied using the technique of constructing the age spectra of the adoles-cent population, which revealed the regularities of the natural pine recovery process. The aim of the study was to conduct a comparative analysis of the broad-leaved species renewal under the coniferous (pine) plantations canopy in forest-steppe conditions using the example of the Belgorod region. The research was carried out on 21 test areas using standard silvicultural techniques to assess natural regeneration effectiveness. Quercus robur L. and Ulmus laevis Pall. prevail among deciduous species in the second layer. Tilia cordata Miill, Fraxinus excelsior L., Acer platanoides L., Acer compestre L. reach less than 12%. (Betula pendula Ehrh., Populus tremula L.). The average number of young growth does not exceed 2000-2500 trees per hectare where the ones of medium height prevail (50%) and small height trees reach 22%. In the considered pine stands, Quercus robur L. young growth occurs more often. There is a growth that appeared from dormant buds at the root neck after the death of the seed unit. Units of normal vitality are found only among young growth younger than 5 years old or in communities with a disturbed stand structure.

Revisiting Thin-Layer Electrochemistry in a Chip-Type Cell for the Study of Electroorganic Reactions

It is important but challenging to elucidate the electrochemical reaction mechanisms of organic compounds using electroanalytical methods. Particularly, a rapid and straightforward method may be helpful if it can provide information on reaction intermediates or other key electrochemical parameters. In this work, we exploited the advantages of classic thin-layer electrochemistry to develop a thin-layer electroanalysis microchip (TEAM). TEAM provided better resolved voltammetric peaks than under semi-infinite diffusion condition owing to the small height. Importantly, rapid and accurate determination of the number of electrons transferred, n, was enabled by mechanically confining the microliter-scale volume analyte at the electrode, while securing ionic conduction using polyelectrolyte gels. The performance of the TEAM was validated using voltammetry and coulometry of standard redox couples. Utilizing TEAM, a (spectro)electrochemical analysis of FM 1-43, an organic dye widely used in neuroscience, was successfully performed. It was also applied to study the electrochemical oxidation mechanism of pivanilides and alkyltrifluoroborate salts with different substituents and solvents. This work suggests the TEAM as a promising tool to provide invaluable mechanistic information and promote the rational design of electrosynthetic strategies.

Constructing totally p-adic numbers of small height

Bombieri and Zannier gave an effective construction of algebraic numbers of small height inside the maximal Galois extension of the rationals which is totally split at a given finite set of prime numbers. They proved, in particular, an explicit upper bound for the lim inf of the height of elements in such fields. We generalize their result in an effective way to maximal Galois extensions of number fields with given local behavior at finitely many places.

Colorectal Adenocarcinoma Cell Culture in a Microfluidically Controlled Environment with a Static Molecular Gradient of Polyphenol

To study the simultaneous effect of the molecular gradient of polyphenols (curcumin, trans-resveratrol, and wogonin) and biological factors released from tumor cells on apoptosis of adjacent cells, a novel microfluidic system was designed and manufactured. The small height/volume of microfluidic culture chambers and static conditions allowed for establishing the local microenvironment and maintaining undisturbed concentration profiles of naturally secreted from cells biochemical factors. In all trials, we observe that these conditions significantly affect cell viability by stimulating cell apoptosis at lower concentrations of polyphenols than in traditional multiwell cultures. The observed difference varied between 20.4–87.8% for curcumin, 11.0–37.5% for resveratrol, and 21.7–62.2% for wogonin. At low concentrations of polyphenols, the proapoptotic substances released from adjacent cells, like protein degradation products, significantly influence cell viability. The mean increase in cell mortality was 38.3% for microfluidic cultures. Our research has also confirmed that the gradient microsystem is useful in routine laboratory tests in the same way as a multiwell plate and may be treated as its replacement in the future. We elaborated the new repetitive procedures for cell culture and tests in static gradient conditions, which may become a gold standard of new drug investigations in the future.

PARTICULARITIES OF MAGNETIC FIELD SHIELDING FOR UNDERGROUND CABLE LINE BY COMPOSITE FILL-UP SOIL WITH MAGNETIC PROPERTIES

The computations of the magnetic field generated by high-voltage (330 kV) underground power cable line with special fill-up soil having different dimensions (bulk) are carried out by the two- and three-dimensional computer models. The supplementary soil above the cables is the composite material with effective magnetic properties and serves as a magnetic shield. The computer results obtained by 2D and 3D models are compared. The efficiency of magnetic field shielding depending on the magnetic permeability, width, and height of the fill-up soil is studied. As revealed, there is the optimal small soil height for the best magnetic field mitigation on the top of the ground directly over the cable line. In addition, the width of the magnetic soil has an appreciable effect on shielding efficiency. The shielding of underground single-circuit three-phase power cable lines is efficient only when using the magnetic fill-up soil (or ordinary external screen made of magnetic materials) with enough small height. References 14, figures 7.