Blob (visual system)

Blobs are sections of the visual cortex where groups of neurons that are sensitive to color assemble in cylindrical shapes. They were first identified in 1979 by Margaret Wong-Riley when she used a cytochrome oxidase stain, from which they get their name. These areas receive input from parvocellular cells in layer 4Cβ of the primary visual cortex and output to the thin stripes of area V2. Interblobs are areas between blobs which receive the same input, but are sensitive to orientation instead of color. They output to the pale stripes of area V2.

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Visual system

The visual system is the part of the central nervous system which gives organisms the ability to process visual detail, as well as enabling the formation of several non-image photo response functions. It detects and interprets information from visible light to build a representation of the surrounding environment. The visual system carries out a number of complex tasks, including the reception of light and the formation of monocular representations; the buildup of a nuclear binocular perception from a pair of two dimensional projections; the identification and categorization of visual objects; assessing distances to and between objects; and guiding body movements in relation to the objects seen. The psychological process of visual information is known as visual perception, a lack of which is called blindness. Non-image forming visual functions, independent of visual perception, include the pupillary light reflex (PLR) and circadian photoentrainment.

Structure

This article mostly describes the visual system of mammals, humans in particular, although other "higher" animals have similar visual systems (see bird vision, vision in fish, mollusc eye, reptile vision). In the case of mammals (including humans), the visual system consists of:

Visual 1050

The Visual 1050 was an 8-bit desktop computer sold by Visual Technology in the early 1980s. The computer ran under the CP/M operating system and used 2 400KB, 5¼, SSDD, 96tpi floppy disk drives (TEAC FD-55E) for mass storage with an optional 10Mb external Winchester hard disk drive. In addition to the Zilog Z80 processor clocked at 4 MHz, the Visual 1050 also included a MOS Technology 6502 used as a graphics coprocessor.

Overview

The Visual 1050 featured a dual-processor architecture; Z80A processor as the main CPU and a 6502 to drive the display.

Memory: 160K of RAM was included with the system. 128K of this was programmable and 32K reserved for use by the display processor.

Screen: The display unit was 640×300 pixel, 80×25 character (8×12 dot matrix) green monochrome CRT bit-mapped display. The display offered programmable features which could be invoked from the main processing unit via a character-stream interface built in between the Z80 CPU and 6502 co-processor.

Communication ports An RS-232C serial port and Centronics parallel port.

Blob

Blob may refer to:

In science

In computing

In entertainment

Film and television

Gaming

System

A system is a set of interacting or interdependent component parts forming a complex/intricate whole. Every system is delineated by its spatial and temporal boundaries, surrounded and influenced by its environment, described by its structure and purpose and expressed in its functioning.

The term system may also refer to a set of rules that governs structure and/or behavior. Alternatively, and usually in the context of complex social systems, the term is used to describe the set of rules that govern structure and/or behavior.

Etymology

The term "system" comes from the Latin word systēma, in turn from Greek σύστημα systēma: "whole compounded of several parts or members, system", literary "composition".

History

According to Marshall McLuhan,

"System" means "something to look at". You must have a very high visual gradient to have systematization. In philosophy, before Descartes, there was no "system". Plato had no "system". Aristotle had no "system".

In the 19th century the French physicist Nicolas Léonard Sadi Carnot, who studied thermodynamics, pioneered the development of the concept of a "system" in the natural sciences. In 1824 he studied the system which he called the working substance (typically a body of water vapor) in steam engines, in regards to the system's ability to do work when heat is applied to it. The working substance could be put in contact with either a boiler, a cold reservoir (a stream of cold water), or a piston (to which the working body could do work by pushing on it). In 1850, the German physicist Rudolf Clausius generalized this picture to include the concept of the surroundings and began to use the term "working body" when referring to the system.

System (journal)

System (ISSN 0346-251X) is a peer-reviewed academic journal covering the applications of educational technology and applied linguistics to problems of foreign language teaching and learning. It was established in 1973 and is published quarterly by Elsevier.

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Physical system

In physics, a physical system is a portion of the physical universe chosen for analysis. Everything outside the system is known as the environment. The environment is ignored except for its effects on itself. In a physical system, a lower probability states that the vector is equivalent to a higher complexity.

The split between system and environment is the analyst's choice, generally made to simplify the analysis. For example, the water in a lake, the water in half of a lake, or an individual molecule of water in the lake can each be considered a physical system. An isolated system is one that has negligible interaction with its environment. Often a system in this sense is chosen to correspond to the more usual meaning of system, such as a particular machine.

In the study of quantum coherence the "system" may refer to the microscopic properties of an object (e.g. the mean of a pendulum bob), while the relevant "environment" may be the internal degrees of freedom, described classically by the pendulum's thermal vibrations.