Engineering methodology for calculation of corrugated beams for bending and torsion. Flat bend form stability

An engineering design procedure for calculating bending with torsion in corrugated beams, including finding the critical load of general stability, implemented in the commonly used MS Excel spreadsheet and verified in the LIRA-SAPR software package, has been proposed. The method makes it possible to take into account the beams section variability and corrugation parameters, to estimate the loading eccentricity effect, availability of supporting ribs and reinforcements of the compressed chord from the bending plane. Calculation results of particular design solutions for corrugated beams with definition of critical loads at transverse bending are given. Results of test calculation of a bent channel beam with calculation of stress-strain state parameters and its verification with the LIRA-SAP software package are given

Evaluating the efficiency of heat and power systems by the data envelopment analysis method

The article describes the Data Envelopment Analysis (DEA) method and the main features of its application. The main problems of heat and power systems are described, which are addressed by the DEA method of efficiency assessment presented in the article. The approbation of this method is presented at the objects of the centralized municipal heat supply system of the fuel and energy complex: boiler houses and heat and power plants. 9 objects were analyzed according to four input indicators: available heat capacity, installed heat capacity, heat consumption for own needs, fuel consumption. Also, the efficiency of the system was evaluated according to two output indicators: the release of thermal energy to the grid and the mass of the emission. As a result of the analysis and calculations made, it was revealed that 5 objects have the maximum possible efficiency indicator equal to 1, that is, they function as efficiently as possible. 4 objects of the centralized municipal heat supply system have an efficiency indicator less than 1. Accordingly, improvements are required for the operation of the above Decision-Making Units (DMU)s. These objects have deviations in terms of the inputs and outputs of the actual data and those obtained using the DEA method. Based on the calculations obtained for these 4 objects, the article provides recommendations for changing the quantitative values of their input and output indicators. For example, for object number 2, it is recommended to reduce the installed heat capacity in the grid by 72.57%, without changing the available heat capacity and fuel consumption. Reduce the heat consumption for your own needs by 69.383%. In addition, it is recommended to increase the supply of thermal energy to the grid by 6,034%, and reduce the mass of emission by 11.5%. Specific measures have also been developed to modernize the studied objects in order to achieve the recommended indicators of inputs and outputs. The research results presented in the article are of scientific and practical interest and can be used to improve the efficiency of heat and power systems facilities. © 2021, World Scientific and Engineering Academy and Society. All rights reserve

Study of the conditional flexibility effect of compressed chord on the overall stability of corrugated beams

In this paper, the calculation of cut corrugated beams loaded with uniformly distributed load in the plane of the wall, with a wall height of 333 and 500 mm (54 sizes), chord width from 160 to 400 mm and chord thickness from 6 to 30 mm for general stability in accordance with Building Codes (BC) 294.1325800.2017 is made. A geometric criterion has been defined which defines the boundaries of the load-carrying capacity of Russian corrugated beams between the flat bending form stability and the strength of the normal section under the action of the bending moment in the plane of the wall

Multiple scattering of laser beams in dense hydrosols

The multiple scattering of laser beams is usually described within the framework of small-angle scattering theory. The validity of this approximation as well as improvements due to the incorporation of diffusion theory in the calculations were studied

BIO-INSPIRED DESIGN OF A GRIPPER FOR HARVESTING ROBOT

In this work, a gripper for a harvesting robot was designed and manufactured. Bio-in-spired elements have been applied to the design of the gripper fingers. Evenly distributed strength and minimal structural weight were ensured through computer-aided engineering analysis and topology optimization

Efficacy of immune correcting therapy at varicose vein disease of pelvis minor in women

In the article the complex therapy of varicose vein disease of pelvis minor in women is suggested; it includes phlebotropic, metabolic and immunotropic drugs. Indicated scheme of treatment lead to improvement of hemodynamic parameters of venous system of pelvis minor. Positive changes of parameters of cytokine, cellular and humoral units of immune system are evidence for decrease of inflammatory response of venous vascular wall

Immune response and cytokine status at varicose vein disease of pelvis minor in women

The article describes participation of immune system in pathogenesis of varicose vein of pelvis minor. The study revealed elevation of proinflammatory cytokines, discovered disturbances in cellular and humoral units of immunity. Indicated changes are evidence for inflammatory character of changes in venous vascular wall, causing its destruction and varicose dilatation

On the Opportunities of Using the Indices of Lipid Peroxidation – Antioxidant Defense System in the Diagnostics of Varicose Veins of Small Pelvis in Women

Background: The prevalence of varicose veins of small pelvic veins in women of reproductive age varies widely – from 5.4 to 80 %, due to the low specificity and low sensitivity of clinical diagnostic techniques, and the absence of biomarkers that can be used to identify the formation and progression of varicose veins of small pelvic veins in women.Aims: To identify changes in the levels of parameters of the system “lipid peroxidation – antioxidant protection” with the development of varicose veins of the pelvis in women, as well as the possibility of their diagnostic use.Materials and methods: We examined 200 women with clinical signs of varicose veins of small pelvis. Control group included 30 women without any pathology of venous system. Treatment group included 137 women with varicose veins of small pelvis: with mild degree of severity – 39 women, with moderate degree of severity – 65 women, with severe degree of severity – 33 women. We performed comparative analysis of lipid peroxidation – antioxidant defense system in women with and without varicose veins of small pelvis taking into account the severity degrees of pathological process.Results: We obtained the most informative indices for lipid peroxidation – antioxidant defense processes in blood of women with varicose veins of small pelvis: concentration of diene conjugate (DC) for the mild degree of severity of pathological process, lipid hydroperoxide (LHP), DC and malonic dialdehyde (MDA) – for the moderate and severe degree of severity, and also changes in the activity of antioxidant enzymes with increase of the severity of the disease. Assessment of the level of catalase (Cat) and glutathione peroxidase (GP) showed their highest informative value at the mild degree of severity. Concentrations of glutathione reductase (GR), glutathione S-transferase (GST) and reduced glutathione (GSH) are more statistically significant markers for severe forms of pathological process.Conclusions: Our research showed the relevance and advisability of the studying the levels of lipid peroxidation – antioxidant defense indices in women with varicose veins of small pelvis. We registered the highest diagnostic value of DC, Cat and GP in the beginning of the disease and of LHP, DC, MDA, GR, GST and GSH – at severe forms of the pathological process. We obtained reference values for DC, MDA, Cat, SOD and GP concentration that can be considered as the predictors of the development of varicose veins of small pelvis

The Atmospheric Chemistry Suite (ACS) of Three Spectrometers for the ExoMars 2016 Trace Gas Orbiter

The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 μm—the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7–1.6 μm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2–4.4 μm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7–17 μm with apodized resolution varying from 0.2 to 1.3 cm−1. TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described