Effective Communication Systems: Types, Technologies, and Methods
Communication: An Introduction
Communication is the transmission of information from one place to another. In terms of technology, communication requires a system with a message sender and a receiver.
The communication channel is the means by which the message is transmitted. Transmission occurs through environmental perturbations (signals) that originate in the transmitter until they reach the receiver. Key features include:
- The means by which it is transmitted (atmosphere, water, vacuum, optical
Error Control Codes: Detection and Correction
Error Control Codes in Computer Communication
To enable communication between two different computers, a code is necessary. This code consists of a limited set of symbols combined by specific rules known to both the sender and receiver. When a recipient receives a message coded in natural binary, it contains only digits that can have two values: 0 and 1. Each digit is called a bit.
Error Detection Codes
Binary code is suitable for representing decimal numbers. However, it’s very sensitive to errors
Read MoreDynamic Positioning Systems in Maritime Operations
Dynamically Controlled Vessels
These vessels are capable of maintaining position at sea without the use of moorings or anchors. This is achieved by using propulsion units called computer-controlled thrusters. It is common to see several tunnel thrusters side by side, either at the bow or stern. While tunnel thrusters are fixed, azimuth thrusters can rotate 360 degrees. All these vessels still retain their main thrusters and rudders.
Dynamic Positioning: Principles of Operation
Dynamic Positioning (
Read MoreUnderstanding Control Systems: Proportional, Integral, Derivative & More
Understanding Control Systems
Proportional Control
A proportional (P) control system responds to an error signal, providing a symmetrical correction proportional to the error. A constant error signal results in a constant corrective action. Sudden changes in the error signal lead to a fast response from the controller.
Proportional-Integral Control
In proportional-integral (PI) control, the error signal causes a growing response due to the integral action of the controller. This type of control is suitable
Read MoreUnderstanding Control Actions: Integral, Derivative, Proportional
Integral Action
Moves the valve at a rate proportional to the integral area obtained between the variation of the variable and the set point over time.
Time Integral Action
The interval of time during which, when a step input signal is applied, the output signal due to the integral action equals that due to the proportional action.
Reset Windup
This is the phenomenon that occurs when the error decreases while the area under the integral action continues to increase. This may lead to saturation of the
Read MoreTRIAC and GTO Thyristors: Operation and Advantages
TRIAC
- An SCR is a unidirectional device; it can conduct from anode to cathode only and not from cathode to anode.
A TRIAC can conduct in both directions.
TRIAC: Bidirectional thyristor with three terminals.
Extensively used for the control of power in AC circuits.
- A TRIAC is a bidirectional device, and its terminals can have various combinations of positive and negative voltages. There are four possible electrode potential combinations, as given below:
MT2 is positive with respect to MT1, G positive with
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