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Published in Min Basadur, Michael Goldsby, Rob Mathews, Design-Centered Entrepreneurship, 2022
Min Basadur, Michael Goldsby, Rob Mathews
A basic understanding of machines may come in handy as you develop prototypes. The Naval Education and Training Program Development Center defines a machine as any device that helps you to do the work. We use machines to transform energy. Another use is to multiply force. Machines may also be used to multiply speed. There are only six simple machines: the lever, block, wheel, axle, inclined plane, screw, and gear. When you are familiar with the principles of these simple machines, you can work on better understanding the operation of complex machines. Complex machines are merely combinations of two or more simple machines.27A little understanding of technology, machinery, and power can provide you with a toolkit to better move an idea further. Of course, you will want to work with technical experts, and you will have a better interaction with them if you understand some basics about machinery.
Electrical science and principles
Published in Trevor Linsley, Electrical Installation Work Level 2, 2019
A lever allows a heavy load to be lifted or moved by a small effort. Every time we open a door, turn on a tap or tighten a nut with a spanner, we exert a lever-action turning force. A lever is any rigid body which pivots or rotates about a fixed axis or fulcrum. The simplest form of lever is the crowbar, which is useful because it enables a person to lift a load at one end which is greater than the effort applied through his or her arm muscles at the other end. In this way the crowbar is said to provide a ‘mechanical advantage’. A washbasin tap and a spanner both provide a mechanical advantage through the simple lever action. The mechanical advantage of a simple lever is dependent upon the length of lever on either side of the fulcrum. Applying the principle of turning forces to a lever, we obtain the formula:
Overview and introduction
Published in Tom Denton, Automobile Mechanical and Electrical Systems, 2018
A simple mechanical machine is a device that allows a small force to overcome a larger force. There are only three basic machines (Fig. 1.67): ramps – such as a wedgelevers – such as a lever!wheels and axles – such as pulleys and a belt.
Combined frequency and voltage regulation in multi-area system using an equilibrium optimiser based non-integer controller with penetration of electric vehicles
Published in International Journal of Ambient Energy, 2023
The secondary controller in the AGC loop plays a vital role in bringing back the deviations in the system dynamics to zero. Without this controller, the time domain responses show a steady-state error. Similarly, the controller in the AVR loop provides a suitable voltage range for the synchronous generator. The researchers in Gupta, Verma, and Chauhan (2020) utilised the PI controller. Authors in Rajbongshi and Saikia (2017) have compared the performance of PI, ID, PID and IDD with filter (IDDF) controllers. Investigations (Ramoji and Saikia 2021a) have utilised TID controllers for combined AGC and AVR investigations. The PID (integer order) controllers are widely used in the industry due to their simple construction and ease of maintenance. However, their performance for time-delayed and nonlinear higher-order system is not superior (Rajbongshi and Saikia 2017). Owing to this, authors (Rajbongshi and Saikia 2018; Lal and Barisal 2019) have utilised the fractional order (FO) controllers, namely FOIDDF (Rajbongshi and Saikia 2018) and FOPID (Lal and Barisal 2019), for combined AGC and AVR studies. However, it is seen that the system with DGs and time delays in the presence of FO controllers is not discussed so far for the combined AGC and AVR system, which is the interest of the authors in the present manuscript.
An efficient color image encryption scheme based on a matrix scrambling method and a new hybrid chaotic map
Published in Cogent Engineering, 2021
Here,,,and represent current plain pixel, output cipher pixel, previous cipher pixel and encryption key, respectively. Modular operation provides the cipher data to the range of [0,255]. Such a mixing operation is very efficient because simple modular arithmetic and logical operations can be performed in high speed. Furthermore, the current cipher pixel depends on the previous one that reflects the diffusion to whole cipher image. In this study, the first cipher value is encoded the first pixel data of the permutated image. However, it can also be used as a secret key parameter for the algorithm. The proposed encryption algorithm has a symmetric structure that means identical key has to be used for decryption process. The decryption is a reverse diffusion algorithm that is defined in Equation (15).
Mathematics anxiety and self-efficacy as predictors of mathematics literacy
Published in International Journal of Mathematical Education in Science and Technology, 2022
Suzanne E. Hiller, Anastasia Kitsantas, Jehanzeb E. Cheema, Maria Poulou
In an effort to clarify the interactive effect of self-efficacy and anxiety on mathematics literacy, we have provided a visualization of the interaction in Figure 1. In order to construct this figure, we converted anxiety to an ordinal variable with three levels (low, medium, high) using M 1 SD as cutoffs. The mathematics literacy values plotted on the vertical axis of Figure 1 have been adjusted for the effect of all variables not included in this figure. The simple regression lines presented in Figure 1 demonstrates that although an increase in mathematics self-efficacy improves mathematics literacy for all mathematics anxiety groups, the effect is greatest for the medium anxiety group.