Introduction

The ability to use words as verbal means of communication is only with humans. Various vocal sounds can be produced using the vocal organs. The main organs which effect the production are the lungs, larynx, vocal folds, the vocal tract, the tongue and the lips. The control of these vocal organs is quite complex. The speech is analyzed using spectrogram. The speech production is explained using the source filter theory. The consonants and the vowels are quite different in their production while for vowels are made by fairly open vocal tract the consonants are made by constriction in the tract. In this presentation we have tried to explain the production of the vowels using the source filter theory. The larynx acts as the source its variation is quite complicated so we have used an artificial vocal cord model to represent the variation. We have tried to model the speech production in humans as a combination of two systems one the source other the filter. The inputs to the system are many but we have tried a simple model using the basic inputs for the cord and the tract. Using this we have studied the various properties of this system.

Ears are important sensory organ in a human body. The ears contain structures for both the sense of hearing and the sense of balance. They indicate direction of sound source better than eye and they are omni-directional. The human ear's purpose in the area of hearing is to convert sound waves into nerve impulses. These impulses are then perceived and interpreted by the brain as sound. The human ear analyzes sound into its frequency components not by its waveform. This is because almost all sounds are structured in frequency and it is easier to detect the sound in presence of other sounds. The human ear is made of three distinct areas: the outer ear, the middle ear, and the inner ear. The outer ear channels sound waves through the ear canal to the eardrum. The eardrum moves in response to the changes in pressure i.e. Waveform.The inner ear houses the "cochlea", a spiral-shaped structure that contains the organ of "Corti" - the most important component of hearing. The Corti sits in an extremely sensitive membrane called the "basilar membrane". Whenever the basilar membrane vibrates, small sensory hair cells inside the Corti are bent, which stimulates the sending of nerve impulses to the brain.

In this presentation, we have tried to explain the working of ear through its mathematical model. Ear is taken as a system which acts as converting input sound waves to nerve impulses.