Abstract: The present invention relates to network communication systems for managing client/server connections in a wireless environment. In accordance with the invention, a mobile communication unit (i.e., client), deploys keepalive packets at selected times in order to reset a keepidle timer of a server (e.g., host computer). By periodically resetting the keepidle timer a current connection between the mobile communication unit and server can be maintained as long as desired even when the mobile communication unit is in a power suspend mode. When in a power suspend mode, the mobile communication unit can briefly awake long enough to activate its transmitter and send a keepalive packet to the server to maintain the current connection. In this manner, the mobile communication unit can obtain the power savings of being in primarily a power suspend mode, but still prevent the current connection from timing out.

Abstract: The present invention relates to network communication systems for managing client/server connections in a wireless environment. In accordance with the invention, a mobile communication unit (i.e., client), deploys keepalive packets at selected times in order to reset a keepidle timer of a server (e.g., host computer). By periodically resetting the keepidle timer a current connection between the mobile communication unit and server can be maintained as long as desired even when the mobile communication unit is in a power suspend mode. When in a power suspend mode, the mobile communication unit can briefly awake long enough to activate its transmitter and send a keepalive packet to the server to maintain the current connection. In this manner, the mobile communication unit can obtain the power savings of being in primarily a power suspend mode, but still prevent the current connection from timing out.

Abstract: The present invention relates to network communication systems for managing client/server connections in a wireless environment. In accordance with the invention, a mobile communication unit (i.e., client), deploys keepalive packets at selected times in order to reset a keepidle timer of a server (e.g., host computer). By periodically resetting the keepidle timer a current connection between the mobile communication unit and server can be maintained as long as desired even when the mobile communication unit is in a power suspend mode. When in a power suspend mode, the mobile communication unit can briefly awake long enough to activate its transmitter and send a keepalive packet to the server to maintain the current connection. In this manner, the mobile communication unit can obtain the power savings of being in primarily a power suspend mode, but still prevent the current connection from timing out.

Abstract: The present invention relates to network communication systems for managing client/server connections in a wireless environment. In accordance with the invention, a mobile communication unit (i.e., client), deploys keepalive packets at selected times in order to reset a keepidle timer of a server (e.g., host computer). By periodically resetting the keepidle timer a current connection between the mobile communication unit and server can be maintained as long as desired even when the mobile communication unit is in a power suspend mode. When in a power suspend mode, the mobile communication unit can briefly awake long enough to activate its transmitter and send a keepalive packet to the server to maintain the current connection. In this manner, the mobile communication unit can obtain the power savings of being in primarily a power suspend mode, but still prevent the current connection from timing out.

Abstract: The present invention relates to network communication systems for managing client/server connections in a wireless environment. In accordance with the invention, a mobile communication unit (ie., client), deploys keep alive packets at selected times in order to reset a keep idle timer of a server (e.g., host computer). By periodically resetting the keep idle timer a current connection between the mobile communication unit and server can be maintained as long as desired even when the mobile communication unit is in a power suspend mode. When in a power suspend mode, the mobile communication unit can briefly awake long enough to activate its transmitter and send a keep alive packet to the server to maintain the current connection. In this manner, the mobile communication unit can obtain the power savings of being in primarily a power suspend mode, but still prevent the current connection from timing out.

Abstract: A multiplexed electrical control circuit is provided for use with optical display devices of the type wherein electrical intelligence is translated into optical images of letters or numbers or other patterns through the use of a liquid crystal shutter device fully described in a copending application Ser. No. 136,441, filed Apr. 22, 1971. The shutter device comprises a layer of liquid crystal material sandwiched between opposing parallel plates coated with transparent conducting films. The shutter device, or liquid crystal cell, is disposed between a pair of polarizers such that the application of electrical potential across a character, digit, or other image-defining segment and an opposing position-designating film will cause light to be transmitted or to be cut off, depending upon the orientation of the two polarizers.

Abstract: A liquid crystal welding lens assembly for use as the eyepiece of a welding helmet in which the light transmission of the lens assembly is no greater than 0.01% during the existence of a welding arc. This is achieved with the use of at least two liquid crystal light shutters and three polarizers alternately arranged in tandem.

Abstract: A protective welding lens assembly for use as the eyepiece of a welding helmet. The lens assembly utilizes a liquid crystal light shutter together with an electrical circuit adapted to change the light shutter from a uniform light-transmitting condition to a uniform, approximately opaque condition of very small light transmission solely in response to light energy emitted by an electric welding arc without the use of any connecting wires. Two light sensing devices are employed, one of which responds to visible light only and the other of which responds to infrared wave energy only. In order to change the light shutter from a light-transmitting to an opaque condition, both the visible and infrared wave energies from the arc must be sensed. This prevents a condition wherein the light shutter will remain opaque, even after the welding arc is extinguished, due to emission of infrared wave energy from a still-hot weld bead.

Abstract: Method for producing homogeneous surface alignment of liquid crystal materials by applying to the surfaces of transparent plates bounding a liquid crystal film a polymer which is subjected to a shear thinning technique to cause elongation and alignment of long chain polymers. In certain embodiments of the invention, the surfaces are coated with a polymer treated with a dichroic dye such that a polarizing film is formed adjacent the liquid crystal film. This eliminates the need for separate polarizers on opposite sides of a liquid crystal display.