Circle Diagrams

"Dimensions of service quality.
A customer's expectation of a particular service is determined by factors such as recommendations, personal needs and past experiences. The expected service and the perceived service sometimes may not be equal, thus leaving a gap. The service quality model or the ‘GAP model’ developed by a group of authors- Parasuraman, Zeithaml and Berry at Texas and North Carolina in 1985 , highlights the main requirements for delivering high service quality. It identifies five ‘gaps’ that cause unsuccessful delivery. Customers generally have a tendency to compare the service they 'experience' with the service they 'expect' . If the experience does not match the expectation , there arises a gap. Ten determinants that may influence the appearance of a gap were described by Parasuraman, Zeithaml and Berry. in the SERVQUAL model: reliability, responsiveness, competence, access, courtesy, communication, credibility, security, understanding the customer and tangibles.
Later, the determinants were reduced to five: tangibles; reliability; responsiveness; service assurance and empathy in the so called RATER model." [Service quality. Wikipedia]
The block diagram example "Gap model of service quality" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Block Diagrams solution from the area "What is a Diagram" of ConceptDraw Solution Park.

"In elementary algebra, a quadratic equation (from the Latin quadratus for "square") is any equation having the form
ax^2+bx+c=0
where x represents an unknown, and a, b, and c are constants with a not equal to 0. If a = 0, then the equation is linear, not quadratic. The constants a, b, and c are called, respectively, the quadratic coefficient, the linear coefficient and the constant or free term.
Because the quadratic equation involves only one unknown, it is called "univariate". The quadratic equation only contains powers of x that are non-negative integers, and therefore it is a polynomial equation, and in particular it is a second degree polynomial equation since the greatest power is two.
Quadratic equations can be solved by a process known in American English as factoring and in other varieties of English as factorising, by completing the square, by using the quadratic formula, or by graphing." [Quadratic equation. Wikipedia]
The flowchart example "Solving quadratic equation algorithm" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Mathematics solution from the Science and Education area of ConceptDraw Solution Park.