Performance Analysis and Development of a Semiconductor Junction Rectifier with Multicolor Coding for Indoor Farm Applications

This paper aims to build a smart lighting system with applications such as remote for controlling power supply and optimizing heat management in the metal body of the semiconductor diode and with a printed circuit board for agriculture. The semiconductor diode strips with multiple colors are lined up and configured as a LED lamp with proper casing and heat sink. It has a driver circuit with required power regulation that is able to control the intensity of light for photosynthesis and plant growth requirements. The system uses hydroponics to plant the water, thus decreasing the usage of fertilizers. The entire system is controlled remotely using necessary communication interface application.

PROMISING PULSE AND VIBRATION SHOCK DEVICE FOR UNLOADING OF TRAILERVEHICLES

Due to the growth of bulk cargo transportation by road, it is necessary to increase the level of mechanization and automation of loading and unloading operations. In recent years, various powerful high-performance unloading machines of original designs (car tippers, vibrating platforms, elevators, etc.) have been created to mechanize unloading processes. This makes it possible to speed up unloading, reduce costs and reduce excessive downtime of dump trucks under unloading. However, the use of such machines is cost-effective at unloading points with a turnover of more than 30 dump trucks per day. Therefore, the problem of creating simple and cheap equipment that ensures efficient unloading of dump trucks with bulk cargo, as well as cleaning of rolling stock from cargo residues, as regardless of the type and composition of cargo, some of them are delayed on the floor, in stamped ribs. pockets of all-metal body walls. The largest amount of cargo remains on the hatch covers, the angle of which is on average 300, while the angle of the actual slope of the cargo reaches 450 and more. Due to this ratio of angles, even dry material cannot fall out completely through the hatch opening, let alone moistened or viscous bulk cargoes. The amount of bulk cargo residues depends on many factors (type of cargo, its humidity, size of pieces, air temperature, distance of transportation, method of unloading) and can be from 2 to 30% of the total weight of the cargo [1]. The use of useful vibrations allows to solve this problem the most expediently. Therefore, the development of a vibratory shock device for unloading vehicles is a promising and urgent task.

Differential effects on the toxicity and bioconcentration of hexavalent and trivalent chromium on the rotifer Lecane papuana (Rotifera: Monogononta)

Heavy metals are still a matter of concern as they might reach aquatic environments due to anthropogenic activities like metal-mechanic or mining, which are part of the main economic activities in different regions around the world. The exposure to chromium may be linked to discharges from automotive and tannery industries, representing a threat to aquatic biota. In the environment, chromium presents two stable forms, the trivalent (CrIII) and the hexavalent (CrVI), which differ on their chemical properties, and thus, on their bioavailability and effects on organisms exposed to this metal. Therefore, this work was aimed to assess the effects of both chromium III and VI on the demographic responses of the rotifer Lecane papuana and describe how the bioconcentration of chromium affects survival and fecundity. For this purpose, acute toxicity (48 h) and chronic toxicity test (alterations on the intrinsic growth rate) were carried out. Moreover, the bioconcentration factor (BCF) and metal body burden (MBB) were estimated after 24-h exposure to either CrIII or CrVI. Our results indicate that CrIII was less toxic according to their respective LC50 values (CrIII = 2.613 mg/L; CrVI = 0.177 mg/L). The intrinsic growth rate was significantly affected by CrIII while CrVI caused no significant changes but only at 0.0885 mg/L, which represents 0.5 of their respective LC50 value. Bioconcentration experiments demonstrated that L. papuana accumulated more CrIII before causing deleterious effects, although it was not as toxic as CrVI, which elicited toxic effects on L. papuana at concentrations of environmental concern.

Additive technology to create a tool for electroerosive processing

The paper considers new methods and tools for combined electroabrasive finishing of metal parts, and shows the advantages of such a tool over traditional methods of finishing shaping the surfaces of labor-intensive products made of difficult-to-process alloys. The possibilities of layer-by-layer application of materials using additive technology to reduce labor intensity and cost for combined processing of tools with layers of abrasive on the periphery of a metal body obtained from a low-melting alloy by the additive method are considered. The possibility of accelerated production of tools using this technology, which does not require significant costs for editing and sharpening for specific parts, is shown, which reduces the production time of technological equipment when launching new generations of products, primarily in the aerospace industry of mechanical engineering. The new method and design of the tool are protected by a Russian patent. Experimental operation of wheels made using additive technologies has shown that the use of such a tool in single and small-scale flexible structure production significantly reduces the complexity of manufacturing parts for finishing operations.

CAE Modeling Rubber-metal Body Mounting of the Body-on-frame Car in Crash Simulations

The aim of the study was to research the behavior of the rubber-metal body mounting under various modeling options and to select the optimal, from the point of view of ensuring the accuracy of the results in the crash tests simulations. Body supports provide a link between the body and the car frame, and this has a critical effect on the impact test results of the car. The article discusses various options for modeling the body mounting by the degree of simplification from the simplest model with a rigid connection between the body and the frame to the model that takes into account the non-linearity of the stiffness characteristics of the supports, contact interaction between parts of the mounting and its surrounding parts, tension of the supports and failure. The results of virtual tests of a car with various options for modeling mountings were compared with the results of real tests. As a result of the study, a methodology for modeling the body supports was developed, which allows providing the necessary measurement error in virtual crash test modeling.

Новые типы фотонно-кристаллических двухзазорных резонаторов для миниатюрных многолучевых клистронов коротковолновой части СВЧ-диапазона

The results of three-dimensional electrodynamic modeling of photonic-crystal double-gaps resonators designed for use in miniature multi-beams klystrons. In the new resonators, the solid metal body is replaced by a similarly shaped lattice of metal rods, allowing to suppress parasitic types of vibrations. It is shown that such oscillatory systems have an improved complex of electrodynamic and mass-dimensional parameters. The conditions of tuning these systems to a highly efficient two-mode of interaction are investigated with multi-beam electron flow simultaneously at two frequencies corresponding to the main (antiphase) and the first higher (in-phase) types of oscillations.

Thermal insulating cover for the metal body of a rocket motor

Many years of experience in the design and manufacturing technology of ammunition and rockets by BUMAR AMUNICJA S.A. enabled undertaking, together with the Institute IMPiB Department Elastomers and Rubber Technology in Piastów, the task of developing an upgraded insulation cover for the metal body of the rocket motor of the GROM-M system. The insulating layer of the metal body of the motor is characterised by the fact that local thermal exposure occurring during rocket propellant combustion, often causes the motor body to burn through locally. Applying an insulating composition matched to the temperature of combustion of the rocket motor, brings about a carbonisation process applicable to this temperature. Thus, it provides a sufficient layer of carbon-carbon phase composite at the site to enhance the strength of the motor and protect the above-mentioned metal body from exposure to heat during combustion of the rocket propellant. The thermal insulating layer is a double layered coating consisting of a layer of rubber compound and a layer of impregnated carbon cloth. To obtain uniformity of the insulating layer and hence its heat resistance, similar components are used in the composition of the rubber compound for impregnating a composite based on carbon cloth: the same type of rubber, the same phenol-formaldehyde resin and the same vulcanising agents.