Tag Archives: data

•When selecting which medium is suitable, several factors should be kept in mind: – costs and installation effort, – transmission safety – susceptibility to tapping, interference susceptibility, error probability, etc. – maximum data rate, – distances and topological position of the participants, etc.   Lecture 11-12_Transmission Medi.ppt dosyayı indir

•Digital-to-digital conversion – Encode digital data into a digital signal – Sending computer data •Analog-to-Digital conversion – Digitizing an analog – Sending voice in telephone (Decrease effect of noise ) •Digital-to-Analog conversion – Modulating a digital signal – Sending computer data through public telephone line •Analog-to-Analog conversion – Modulating an analog signal – Sending music from radio station   Lecture …

•Data – A representation of facts, concepts, or instructions in a formalized manner suitable for communication, interpretation, or processing by human beings or by automatic means •Information – The meaning that is currently assigned to data by means of the conventions applied to those data Lecture 3-4_Signals.ppt  dosyayı indir

• More flexible data model than the relational model. – Think of an object structure, but with the type of each object its own business. – Labels to indicate meanings of substructures. • Semi-structured: it is structured, but not everything is structured the same way! lecture13.pdf  dosyayı indir