Condensate-removal device for heat exchangers

Device comprises array of perforated tubes manifolded together and connected to a vacuum suction device. Vacuum applied to these tubes pulls mixture of condensate and effluent gas through perforations and along length of tubes to discharge device. Discharge device may be a separator which separates water vapor from effluent air and allows recirculation of both of them

Condensate removal device for heat exchanger

A set of perforated tubes disposed at the gas output side of a heat exchanger, in a position not to affect the rate of flow of the air or other gas is described. The tubes are connected to a common manifold which is connected to a sucking device. Where it is necessary to conserve and recirculate the air sucked through the tubes, the output of the manifold is run through a separator to remove the condensate from the gas. The perforations in the slurper tubes are small, lying in the range of 0.010 inch to 0.100 inch. The tubes are disposed in contact with the surfaces of the heat exchanger on which the condensate is precipitated, whether fins or plates, so that the water may be directed to the tube openings by means of surface effects, together with the assistance of the air flow. Only about 5 percent of the air output need be thus diverted, and it effectively removes virtually all of the condensate

Social and emotional adjustment across aggressor/victim subgroups: Do aggressive-victims possess unique risk?

Both theory and empirical evidence support the existence of “aggressive-victims,” a subgroup of youth who have been found to experience the negative outcomes associated with being an aggressor and being a victim. It remains unclear, however, if aggressive-victims possess risk factors that are unique from youth who are either aggressive or victimized. The present study sought to: (a) identify subgroups of seventh grade adolescents who differ in their patterns of aggression and victimization, (b) determine the number and structure of subgroups differ by school or sex, and (c) investigate whether aggressive-victims differ from all other subgroups in their social and emotional functioning. Secondary analyses were conducted on baseline data from 984 seventh grade adolescents participating in a randomized controlled trial evaluating an expressive writing intervention. Latent class analysis identified four subgroups of adolescents representing predominant-aggressors, predominant-victims, aggressive-victims, and youth with limited involvement. This pattern was consistent across sex and across schools that differed in the demographics of the adolescents. The findings indicate that aggressive victims are highly similar to predominant-aggressors and do not possess any unique characteristics beyond their pattern of involvement in both aggression and victimization. Further evidence of unique differences in risk factors is needed to support prevention and intervention efforts that are tailored to meet the specific needs of aggressive-victims. Future research should consider addressing methodological limitations of the present study, such as by examining continuous indicators, including additional indices of social and emotional functioning, or investigating differential item functioning

Galileo early cruise, including Venus, first Earth, and Gaspra encounters

This article documents Deep Space Network (DSN) support for the Galileo cruise to Jupiter. The unique trajectory affords multiple encounters during this cruise phase. Each encounter had or will have unique requirements for data acquisition and DSN support configurations. An overview of the cruise and encounters through the asteroid Gaspra encounter is provided

Breaking the cycle: A longitudinal study of factors that disrupt peer selection and influence processes among urban youth

Having friends who engage in problem behavior (i.e., aggression, substance use, delinquency) has consistently been linked to adolescents’ own engagement in problem behavior. There are, however, several key gaps in the literature on peer influence. Few studies have considered the influence of friends’ prosocial behavior and there has been limited research to identify promotive factors that influence urban youths’ affiliation with peers who engage in problem and prosocial behavior across early adolescence, a time of heightened susceptibility to peer influence. The purpose of this study was to identify modifiable promotive factors that reduce adolescents’ problem behavior by decreasing exposure to friends’ delinquent behavior and promoting affiliation with peers who engage in prosocial behavior. Specifically, the promotive effects of a positive future orientation, the presence of a caring adult, and child disclosure were examined given prior evidence of relations between these factors, peer affiliation, and problem behavior. Analyses were conducted on four waves of longitudinal data collected within the same year from 2,710 students attending three urban middle schools (Mage = 12.3; 52% female) who participated in an efficacy trial of a bullying prevention program. Seventy nine percent of participants identified as Black/African American (including 6% who endorsed one or more other racial identities). One-sided cross-lagged mediation analyses found support for friends’ delinquent behavior as a mediator of longitudinal relations between child disclosure and changes in physical aggression, substance use, and delinquency. Similar effects were not found for positive future orientation or presence of a caring adult. Friends’ prosocial behavior did not significantly mediate longitudinal relations between promotive factors and adolescent problem behavior. Findings suggest prevention efforts should enhance adolescents’ communication with their parents about their activities and whereabouts to disrupt peer influence dynamics and reduce problem behavior during early adolescence. Additional implications for theory and prevention efforts relevant to the positive development of youth in urban low-income communities are discussed

Perception of aircraft separation with pilot-preferred symbology on a cockpit display of traffic information

The concept of a cockpit display of traffic information (CDTI) was developed for use in later full mission simulator evaluations of the CDTI concept. Pilots chose their preferred method of displaying air traffic information for several variables. Variables included: type of background, update rate, update type, predictor type, and history type. Each pilot designed a display he felt would be most useful in flight operations. After a series of test trials, each pilot was given the opportunity to modify the display for the experimental task. For a second day of testing, they repeated the experimental task using their display as well as displays chosen by other pilots. Results indicated a variety of individual preferences in symbology and differences in the accuracy of judgments. Pilots indicated concern for clutter of the display, relationship of the displayed symbology to physical reality, and a need to perceive the relative motion of the intruder aircraft. Analysis of data indicated that pilots were able to improve their performance with practice

Effect of display update interval, update type, and background on perception of aircraft separation on a cockpit display on traffic information

The concept of a cockpit display of traffic information (CDTI) includes the integration of air traffic, navigation, and other pertinent information in a single electronic display in the cockpit. Concise display symbology was developed for use in later full-mission simulator evaluations of the CDTI concept. Experimental variables used included the update interval motion of the aircraft, the update type, (that is, whether the two aircraft were updated at the same update interval or not), the background (grid pattern or no background), and encounter type (straight or curved). Only the type of encounter affected performance

The use of oil for in-flight flow visualization

Oil was used to visualize inflight aerodynamic characteristics such as boundary layer transition, shock wave location, regions of separated flow, and surface flow direction. The technique, which is similar to wind tunnel oil-flow testing, involves an oil mixture to test aircraft before takeoff. After takeoff, the airplane climbs immediately to the test altitude and photographs are taken. The developmental experience is summarized, several examples of inflight oil-flow photographs are presented and discussed, and an approach for potential users of the technique is presented

The effect of viewing time, time to encounter, and practice on perception of aircraft separation on a cockpit display of traffic information

The concept of a cockpit display of traffic information (CDTI) includes the integration of air traffic, navigation, and other pertinent information in a single electronic display in the cockpit. Two studies were conducted to develop a clear and concise display format for use in later full-mission simulator evaluations of the CDTI concept. Subjects were required to monitor a CDTI for specified periods of time and to make perceptual judgments concerning the future position of a single intruder aircraft in relationship to their own aircraft. Experimental variables included: type of predictor information displayed on the two aircraft symbols; time to encounter point; length of time subjects viewed the display; amount of practice; and type of encounter (straight or turning). Results show that length of viewing time had little or no effect on performance; time to encounter influenced performance with the straight predictor but did not with the curved predictor; and that learning occurred under all conditions

Toxicity of thermal degradation products of spacecraft materials

Three polymeric materials were evaluated for relative toxicity of their pyrolysis products to rats by inhalation: Y-7683 (LS 200), Y-7684 (Vonar 3 on Fiberglass), and Y-7685 (Vonar 3 on N W Polyester). Criteria employed for assessing relative toxicity were (1) lethality from in-chamber pyrolysis, (2) lethality from an outside-of-chamber pyrolysis MSTL Procedure, and (3) disruption of trained rats' shock-avoidance performance during sub-lethal exposures to in-chamber pyrolysis of the materials