The equivalent resistance model of double-layer embroidered conductive lines on nonwoven fabric

To reveal the engineering relationship among the electrical properties of embroidered conductive lines, the electrical properties and arrangements of conductive yarns, it is necessary to establish their equivalent resistance model. Embroidered conductive lines in textiles are usually fabricated by single-layer (conductive and nonconductive yarn used as upper and lower yarn) or double-layer embroidery technology (conductive yarns used as upper and lower yarn). Several researchers have proposed the simple resistance model for single-layer embroidered conductive line based on geometric structure of single conductive yarn in fabric. However, the double-layer conductive line has the contact resistance periodically interlaced by the upper and lower conductive yarns, and it made its equivalent circuit different from that of single-layer conductive line. In this work, a geometric model was built to describe the trace of conductive yarn in fabric, and in combination with Wheatstone Bridge theory, was applied to establish the equivalent resistance models of double-layer conductive lines with a certain width, consisted of various courses. First, the equivalent resistance model of double-layer conductive lines consisting of single course was proposed to calculate the contact resistance. Then, to obtain the electrical resistance of double-layer conductive lines with a certain width, the equivalent resistance model was extended from single course to multiple courses ([Formula: see text]). Finally, to validate the proposed equivalent resistance model, double-layer conductive lines with different embroidery parameters (stitch length and stitch spacing) on nonwoven fabric were fabricated and evaluated. The experimental results revealed that the proposed model accurately predicted the resistances of double-layer conductive lines.

Algorithms for estimating equivalent resistances of in-plant electrical networks

THE PURPOSE. Investigation of the degree of influence of the characteristics of in- plant electrical networks on the reliability of the results in the algorithms for estimating equivalent resistances. METHODS. When solving this problem, a study of the radial power supply scheme of the tool shop section was carried out with the calculation and modeling of equivalent and reference values of the circuit resistances. Algorithms and methods for estimating the values of equivalent resistances have been developed, taking into account the main technical characteristics of in-plant networks.RESULTS. The data of calculations of the equivalent resistance values of the circuits with an assessment of the heating factor of the conductors and the resistance factor of the contact devices are analyzed. The proportions of the influence of the resistances of the contact equipment and lines, taking into account the number of electric power receivers connected to the power point, on the value of the equivalent resistances of the circuit are revealed. CONCLUSION. The article develops algorithms for estimating the values of equivalent resistances of in-plant power supply circuits. Nomograms are presented that take into account the number and length of the circuit lines with the allocation of the zone of accounting for the resistances of contact equipment in the equivalent resistances of the circuits. The obtained algorithms and results are recommended to be used to clarify the amount of power and electrical energy losses in the intra- factory networks, which will increase the reliability of calculations.

Influence of low-voltage electrical switching and protecting devices and parameters of electrical equipment on electricity losses in workshop power supply networks

THE PURPOSE. To develop an algorithm for estimating electricity losses, taking into account the influencing factors in the main circuits of shop power supply. To study the influence of the main parameters of electrical equipment on the equivalent resistance of the distribution busbar. METHODS. We use element-by-element methods for calculating active power losses using equivalent resistance on the example of a section of the main circuit of the shop network. Factors affecting the equivalent busbar resistance, such as the root-mean-square load factor, the load graph shape factor, the resistance of the contact connections of switching devices, and the ambient temperature, are investigated. RESULTS. The values of the resistances of the branch lines from the busbar are calculated taking into account the heating of the conductors and the resistances of the circuit breakers and magnetic starters installed on the line during the element-by-element calculation. The relations in the value of the equivalent resistance of the busbar to the values of the resistances of the contact connections of low-voltage electrical devices installed on the branch lines from the busbar, the values of the resistances of the branch lines taking into account heating, the value of the resistance of the busbar and the values of the resistance due to the heating of the busbar are revealed. CONCLUSIONS. The share of each of the studied parameters in the value of the equivalent resistance of the busbar is determined. The value of the relative error in determining the equivalent resistance of the busbar depending on the number of connected electric receivers and taking into account the studied parameters is calculated. The estimation of the value of the electricity losses of the section of the main scheme of the shop network was carried out in accordance with the daily schedule of the load of consumers.

Parameter Estimation of a Countershaft Brake for Heavy-Duty Vehicles with Automated Mechanical Transmission

A countershaft brake is used as a transmission brake (TB) to realize synchronous shifting by reducing the automated mechanical transmission (AMT) input shaft’s speed rapidly. This process is performed to reduce shifting time and improve shifting quality for heavy-duty vehicles equipped with AMT without synchronizer. To improve controlled synchronous shifting, the AMT input shaft’s equivalent resistance torque and the TB’s characteristic parameters are studied. An AMT dynamic model under neutral gear position is analyzed during the synchronous control interval. A dynamic model of the countershaft brake is discussed, and its control flow is given. The parameter identification method of the AMT input shaft’s equivalent resistance torque is given on the basis of the least squares algorithm. The parameter identification of the TB’s characteristic parameters is proposed on the basis of the recursive least squares method (RLSM). Experimental results show that the recursive estimations of the TB’s characteristic parameters under different duty cycles of the TB solenoid valve, including brake torque estimation, estimation accuracy, and braking intensity estimation, can be effectively estimated. The research provides some reliable evidence to further study the synchronous shifting control schedule for heavy-duty vehicles with AMT.

Accentuated Eccentric Loading is Superior to Traditional Loading for Improving Acute Countermovement Jump Performance in Adult, Resistance-Trained Males

Clinical Scenario: Traditional loading (TL) is a common technique to employ when engaging in countermovement jumps (CMJ). Accentuated eccentric loading (AEL) is a newer modality that is being explored for acute CMJ performance. Focused Clinical Question: In adult, resistance-trained males, will AEL have a superior impact on acute CMJ performance compared to TL? Summary of Key Findings: The literature was searched for studies that examined the influence of AEL on acute CMJ performance compared to a TL protocol. TL was defined as any loading condition that utilized an equivalent resistance during both the eccentric and concentric contractions. Three studies met the inclusion and exclusion criteria, and were identified and included in the critically appraised topic. Each of the 3 studies found that various AEL conditions were either equal to or better than TL when examining subsequent CMJ performance. In no specific CMJ outcome measure was TL deemed to have a greater impact than AEL. Clinical Bottom Line: AEL provides more favorable acute CMJ performance than TL in adult, resistance-trained males. Strength of Recommendation: Consistent findings from 2 randomized crossover studies and one repeated-measured design investigation suggest level 2b evidence to support AEL as an ideal protocol for acute CMJ performance.