Raytheon

About: Raytheon is a company organization based out in Waltham, Massachusetts, United States. It is known for research contribution in the topics: Signal & Antenna (radio). The organization has 15290 authors who have published 18973 publications receiving 300052 citations.

Liquid carbon dioxide cleaning using jet edge sonic whistles at low temperature

Abstract: A cleaning system (10) and method utilizing sonic whistle agitation to enhance the soil removal and mass transport capacity of the liquid carbon dioxide (20) at low process temperatures Sonic whistles (61) are within a cleaning chamber (40), and liquid carbon dioxide (20) is forced out of the sonic whistle jets to ultrasonically emulsify and disperse non-miscible liquids or insoluble solids, such as remove low solubility oils and greases, in the liquid carbon dioxide contained in the cleaning chamber Cleaning is accomplished at temperatures between -68 °F and 88 °F, and the temperature of the liquid carbon dioxide is typically below 32 °F

Creative patterns and stimulation in conceptual design

Abstract: Conceptual design is a creative process. Designers create functions to satisfy customer needs and behaviors and forms to fulfill their functions. Although cognitive processes are at the center in developing new ideas, they are rarely taken into account in research and development of design support methods and systems. It is conceivable that if one understands how cognitive processes are stimulated to generate design ideas, then more effective methods and tools can be developed to support conceptual design. In this article, a cognitive model of conceptual design is developed to capture the relationships among design entities, design operations, and cognitive processes. A protocol analysis is performed to evaluate the model, and a cognitive experiment carried out to study the creative patterns and stimulating relationships. The results show that designers exhibit patterns of creative design behavior, and that these patterns can be captured and instilled into the design process to promote creativity.

Frequency- and time-dependent gain characteristics of dye lasers

Abstract: The approach used by McCumber for treating phonon-terminated lasers is applied to investigate the gain properties of dye lasers and is extended to include effects arising from population buildup in the triplet-level system and associated triplet-triplet absorptive losses. The gain is expressed in terms of time-dependent excited-state populations and spectral emission and/or absorption functions. For a given optical-pump pulse, a computer program is used to solve rate equations for the populations up to threshold and to calculate the gain as a function of time and frequency. The gain varies with frequency over the broad fluorescence bands characteristic of dye molecules and with time until the threshold for laser action is reached. Experiments using rhodamine 6G verify the predicted dependence of the laser frequency and time of threshold on cavity Q and demonstrate laser frequency tuning by adjusting the opening time of an intracavity Q switch. No variation of laser frequency is expected for fluorescing molecules exhibiting large Stokes shifts; this is observed for 7-hydroxycoumarin. Computer calculations of the gain for anthracene and rhodamine B illustrate the dependence of gain properties on the rate of intersystem crossing and triplet-triplet absorption. An estimate of the rate of intersystem crossing for rhodamine B in methanol is obtained from a comparison of predicted and observed laser threshold conditions. Requirements for achieving flashlamp-pumped laser action are shown to depend upon both flashlamp and dye properties and are analyzed using the above approach.

Detector and method for detecting telephone-activated devices in idle state

Abstract: A detector for detecting telephone-activated devices, such as cellular telephones used for remotely triggering explosive devices, includes a transmitter for generating and transmitting a pseudo base station signal corresponding to a base station for a telephone-activated device, and a receiver for receiving and detecting a response signal transmitted by the telephone-activated device. At least part of the transmitter and at least of the receiver may be located within a shield of conductive material, such as a cone-shaped metal shield, that aids in localizing and directing the transmitting of the pseudo base station signal toward an object to be interrogated (with regard to whether or not it contains a telephone-activated device in an idle state). The detector has a response unit for providing a response when a telephone-activated device is detected, such as providing an alarm to an operator or interdicting operation of the telephone-activated device.

Serpentine robotic crawler

Abstract: A serpentine robotic crawler capable of multiple movement moves is disclosed. The serpentine robotic crawler includes a plurality of frame units, coupled together by at least one actuated linkage. Each frame unit includes a continuous track, enabling forward movement of the serpentine robotic crawler. The at least one actuated linkage has at least 7 degrees of movement freedom, enabling the serpentine robotic crawler to adopt a variety of poses.