TECHNOLOGICAL OPTIMIZATION OF POSITIONING PRISMATIC-BODY DETAILS IN HOLDING DEVICES

The aim of the present work is to propose and substantiate a scheme of a device for positioning prismatic-body details on two holes with parallel axes and a plane, perpendicular to them. This will help to achieve high accuracy of linear and angular orientation of the workpiece. Thus the requirements for the accuracy of the center-to-center distance of the base holes will be reduced and the process of assembling the workpiece to the grip pawls will be simplified.

Surface Roughness and Fiber Angular Orientation Analysis Toward Laminated Composite Crack Propagation

Composite is a material that consisting of two or more materials, either micro or macro, where the properties of the material differ in shape and chemical composition from the original substance. In this study, fatigue testing of fiber metal composites was carried out to determine the rate of crack propagation so that the age of the fiber metal composite specimen was known. The independent variable in this research is the angular orientation of the carbon fiber and the surface roughness of the aluminum with the dependent variable response is the bridge crack rate. The manufacture of fiber metal laminates specimens uses the Vacuum Resin Infuse (VARI) method, which uses a vacuum pump as a means to flow the resin from the reservoir to the mold. This method is used to minimize the occurrence of air bubbles trapped on the specimen which causes porosity defects which will reduce the strength of the metal laminates specimen itself. Fatigue testing is performed using the stress amplitude method. That is, the value of the load when the tensile test is one third of the tensile strength. After the fatigue test was carried out, the results were obtained on specimens with an angular orientation of 0/90 ° fibers, the crack propagation rate slowed down with a cycle value of 90000 in specimens with a surface roughness value of 2.128 µm then decreased cycles on specimens with a value of 2.887 µm, namely 11000 cycles.

Looking for Targets to Restore the Contractile Function in Congenital Myopathy Caused by Gln147Pro Tropomyosin

We have used the technique of polarized microfluorimetry to obtain new insight into the pathogenesis of skeletal muscle disease caused by the Gln147Pro substitution in β-tropomyosin (Tpm2.2). The spatial rearrangements of actin, myosin and tropomyosin in the single muscle fiber containing reconstituted thin filaments were studied during simulation of several stages of ATP hydrolysis cycle. The angular orientation of the fluorescence probes bound to tropomyosin was found to be changed by the substitution and was characteristic for a shift of tropomyosin strands closer to the inner actin domains. It was observed both in the absence and in the presence of troponin, Ca2+ and myosin heads at all simulated stages of the ATPase cycle. The mutant showed higher flexibility. Moreover, the Gln147Pro substitution disrupted the myosin-induced displacement of tropomyosin over actin. The irregular positioning of the mutant tropomyosin caused premature activation of actin monomers and a tendency to increase the number of myosin cross-bridges in a state of strong binding with actin at low Ca2+.

Methodology for assessing the range of reception by modern telemetric means when launching products from cosmodromes

Проведен анализ места размещения измерительного пункта с точки зрения получения полного объема телеметрической информации при пусках изделий с заданного космодрома. Методика оценки дальности приема основана на расчёте зон радиовидимости стационарных измерительных пунктов по трассе выведения с учетом угловой ориентации изделия в ходе полета, расчёте энергетического запаса радиолиний для существующих и перебазируемых средств приёма телеметрической информации, оценке потерь уровня сигнала в радиолинии, проверке отсутствия экранирования радиолинии факелом двигателя. The analysis of the location of the measuring point from the point of view of obtaining the full volume of telemetric information when launching products from a given cosmodrome is carried out. The method for assessing the reception range is based on calculating the radio visibility zones of stationary measuring points along the injection route, taking into account the angular orientation of the product during flight, calculating the energy reserve of radio lines for existing and relocatable means of receiving telemetry information, assessing the signal level loss in the radio line, checking the absence of shielding of the radio line by the engine torch.