operation(redirected from Abbe-Estlander operation)
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the process of finding a particular quantity (data element) as the result of performance by a digital computer of special actions ordered by a program instruction on one or more initial quantities. The quantities that are the object of the operation are called operands. A distinction is made among data-processing, or computational, operations; control operations; and operations on program instructions (address-substitution operations).
The following computational operations may be distinguished: arithmetical, logic bit-by-bit, and logic operations. Arithmetical operations (addition, subtraction, multiplication, and division) are those that are performed according to the rules of arithmetic; the operands and the results of arithmetical operations are usually numbers in various forms of representation (with fixed or floating decimal point; fields of variable length) and various systems of notation, such as binary, ternary, or decimal. Logic bit-by-bit operations—logical addition, multiplication, biconditional implication and nonimplication (that is, comparison)—are performed according to the rules of algebraic logic; the operands and results of such operations are individual bits of the initial quantities represented in binary form. Logic operations, such as search, access, sorting, and grouping, are performed on certain bits of the operands or sets of bits (digits, letters, symbols, or bytes). Control operations ensure performance of the program and operation of the computer devices. They include control transfer, cycle organization, access to peripherals, routing of data, interruption of the master program, and changes of the mode of operation of the devices (start, stop, search a zone, read, write, and so on). In address-substitution operations (instruction modification), the operands are the actual instructions of the program. These operations play a large part in the writing of looped programs and in the provision for simultaneous operation on several programs.
Computers can perform various operations by hardware and hardware-software methods. In the second method the elementary operations (micro-operations) that make up more complex operations (macro-operations) are performed by hardware in a sequence determined by the program of the particular macro-operation. The higher the performance of the computer, the greater the assortment of operations that can be performed by hardware. The range of operations of a specialized digital computer is determined by the specific features of the class of problems it solves; for a general-purpose computer the set of operations is chosen by calculating the convenience of solving various classes of problems.
G. B. SMIRNOV
the totality of strikes, encounters, and battles, coordinated and interrelated by objective, time, and place and conducted by operational commands of one or more armed services according to a single concept and plan for fulfilling operational or strategic missions.
The operation as a form of waging military actions first appeared in the wars of the late 18th century and early 19th; the concept of the “operation” took shape practically and theoretically in the early 20th century. By the mid-1930’s the theory of waging a deep offensive operation with massive use of tanks, aviation, artillery, and airborne landings had been worked out in the Soviet armed forces. Present-day operations may include land, naval, air, and airborne operations.
In terms of objectives, operations may be offensive or defensive, whereas in terms of time, they are either simultaneous or successive (one develops another). Depending on the composition of forces involved, operations are classified as strategic, front (groups of armies), fleet, army, or flotilla operations. The objectives and content of an operation are determined by the military and political objectives of the combatants in the theater of war, the composition of participating forces, the concrete conditions of the operational-strategic situation, the nature of the actions of enemy and friendly forces, and terrain conditions. The most typical indexes of the scope of an offensive operation are its depth, duration, width of zone of attack, and rate of advance of forces. For the defensive operation, the indexes are the width of the zone, the depth of construction of the defense, and the duration of the defensive operation. The preparation for and conduct of operations are the subject of strategy and operational art.
P. K. ALTUKHOV
What does it mean when you dream about an operation?
A medical procedure being performed on the dreamer may signify old issues being “cut out” or patched up. If the dreamer is doing the operating, then deep unconscious issues are being faced, worked on, and healed. The overall implication of this dream depends on one’s experiences with medical operations.
operation(1) See operation code.
(2) Any manual or machine activity. See process.