Osman Pehlivanoğlu 030040089 3rd Week

Variational Design
In variational design, the entire system of constraints for a part or parts is solved simultaneously with a constraint solver (e.g., Newton-Raphson). Variational design systems offer several advantages including the ability to solve problems whose dimensions cannot be calculated with a single algebraic expression as well as subsuming most of the capabilities of parametric desing systems. An entire design sequence in a parametric design system can be thought of as a system of constraints in a variational design system. (A Mathematical Theory of Design, Dan Braha, p 388)

Abrasive Machining
Abrasive machining or grinding is a chip-forming metal cutting operation. Most of us are familiar with the grinding wheels, used to sharpen knives and other tools, and sand paper which is used to smoothen surfaces and sharp corners. For grinding, generally, a rotating grinding wheel is used as a tool. The grinding wheel and sand paper consist of bonded abrasives. The abrasive grains have sharp edges that project out and cut the chips. In grinding, the high circumferential speed of the grinding wheel causes high friction and chips become red hot and fly as sparks.
In grinding and other abrasive machining processes, a very large number of tiny cutting edges simultaneously cut the surface, each taking a very minute cut. (Elements of Manufacturing Processes, Nagendra Parashar, p171)

Ladder Diagram
Ladder Diagram has been developed by the IEC by considering the most commonly used symbols and terminology used in mainstream PLCs.
Ladder Diagram is based on a technique used to design logic using relays. A Ladder Diagram always has a left hand vertical power rail that notionally supplies power through contacts spread out along horizontal rungs. (Programming Industrial Control Systems Using IEC 1131-3, Robert Lewis, 2nd Edition, p153)

Drum-Buffer-Rope System
A drum-buffer-rope production control system has the following basic characteristics.
-The CCR beats the drum to set the pace for entire factory.
-An information rope ties production starts to the CCR.
An inventory buffer at (or heading toward) the constraint protects it from upstream stoppages. (Beyond the Theory of Constraints, William Levinson, p42)