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modem

(Encyclopedia)modem [modulator/demodulator], an external device or internal electronic circuitry used to transmit and receive digital data over a communications line normally used for analog signals. A modem attach...

Sheridan, Philip Henry

(Encyclopedia)Sheridan, Philip Henry, 1831–88, Union general in the American Civil War, b. Albany, N.Y. Although not a brilliant general, Sheridan's flair for leadership and his ready fighting ability made him th...

acceleration

(Encyclopedia)acceleration, change in the velocity of a body with respect to time. Since velocity is a vector quantity, involving both magnitude and direction, acceleration is also a vector. In order to produce an ...

blackbody

(Encyclopedia)blackbody, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation fall...

television

(Encyclopedia)CE5 Video transmission and reception of color and black-and-white television: The camera lens focuses collected light rays into mirrors, which separate the image into its three primary color compon...

Durrës

(Encyclopedia)Durrës do͞orˈəs [key], Ital. Durazzo, city (1989 pop. 82,719), capital of Durrës dist., W Albania, on the Adriatic Sea. The chief seaport of Albania and the leading commercial and communications ...

facsimile

(Encyclopedia)facsimile făksĭmˈəlē [key] or fax, in communications, system for transmitting pictures or other graphic matter by wire or radio. Facsimile is used to transmit such materials as documents, telegra...

Four-H

(Encyclopedia)Four-H or 4-H, organization for boys and girls, generally from 8 to 18 years of age; some states offer programs for younger children, and there are also collegiate programs. 4-H teaches young people l...

Accra

(Encyclopedia)Accra əkräˈ, ăkˈrə [key], city (1984 pop. 867,459), capital of Ghana, a port on the Gulf of Guinea. It is Ghana's largest city and its administrative, communications, and economic center. The ch...

audiovisual education

(Encyclopedia)audiovisual education, educational instruction by means of materials that use the senses of sight and hearing to stimulate and enrich learning experiences. The successful use of motion pictures and ot...