Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Bridge

Pulse Width Modulation for DC Motor Control Based on LM324

Jamal A. Mohammed

Engineering and Technology Journal, 2013, Volume 31, Issue 10, Pages 1882-1896

The DC motor is an important part of an equipment in many industrial applications requiring variable speed and load characteristics due to its ease of controllability.
Nowadays, there are lots of good-quality motor speed controllers on the market. However, their costs are relatively high. A speed controller with both low cost and good performance will be highly marketable, especially for small mobility applications.
The current work allows controlling the speed of a DC motor in both forward and reversing direction, from fully off to fully on. It runs in switch mode so it is quite efficient. In this work, designing motor bi-directional DC control circuit using Pulse Width Modulation (PWM) based on an operational amplifier model LM324 is implemented.
The proposed system offers many advantages such as simple structure, low cost, accurate, quite efficient, lightweight nature, small volume, and bi-directional speed control.

Interference of Scouring action between Pier and Abutment: Primary Approach

Jaafar Sadeq Maatooq

Engineering and Technology Journal, 2008, Volume 26, Issue 5, Pages 565-569

Presented here are the results of a limited experimental program dealing with
the problem describing the scour , which is formed around bridge pier neighboring
abutment . To achieve this the results shown , generally, that the scour depends on
a distance interaction between pier and abutment . A modification factor deals with
this distance presented as a multiplicative factor used with an empirical predictive
formula of scour depth around bridge pier .