5,469 research outputs found
Optical and holographic storage properties of F3, Cu, and Mg-doped lithium niobate
Several samples of iron, copper, and magnesium doped lithium niobate were tested to determine their storage properties which would be applicable to an optical data storage system and an integrated optics data preprocessor which makes use of holographic storage techniques. The parameters of interest were the diffraction efficiency, write power, write time, erase time, erase energy, and write sensitivity. Results of these parameters are presented. It was found that iron doped lithium niobate samples yielded the best results in all parameters except for a few percent higher diffraction efficiency in copper doped samples. The magnesium doped samples were extremely insensitive and are not recommended for use in holographic optical data storage and processing systems
Rotor response for transient unbalance changes in a nonlinear simulation
Transient unbalance shifts were determined not to excite a rotor instability in the high pressure turbomachinery of the Space Shuttle Main Engine using the current rotor dynamic models. Sudden unbalance changes of relatively small magnitudes during fast-speed ramps showed stable nonsynchronous motion depending on the resultant unbalance distribution at subsequent high speed dwells. Transient moment unbalance may initiate a limit cycle subsynchronous response that shortly decays, but a persistent subsynchronous with large amplitudes was never achieved. These limit cycle subsynchronous amplitudes appear to be minimized with lower unbalance magnitudes, which indicates improved rotor balancing would sustain synchronous motion only. The transient unbalance phenomenon was determined to be an explanation for synchronous response shifts often observed during engine tests
Nuclear reactor power as applied to a space-based radar mission
The SP-100 Project was established to develop and demonstrate feasibility of a space reactor power system (SRPS) at power levels of 10's of kilowatts to a megawatt. To help determine systems requirements for the SRPS, a mission and spacecraft were examined which utilize this power system for a space-based radar to observe moving objects. Aspects of the mission and spacecraft bearing on the power system were the primary objectives of this study; performance of the radar itself was not within the scope. The study was carried out by the Systems Design Audit Team of the SP-100 Project
A “Dark Side” of Communication Avoidance: Indirect Interpersonal Aggressiveness
Although our understanding of direct forms of verbal aggressiveness has been greatly advanced over the past decade, indirect interpersonal aggressiveness has remained relatively understudied. In the present study, items designed to tap indirect forms of interpersonal aggressiveness were written, administered to participants, factor analyzed along with verbal aggressiveness items, and correlated with a criterion measure. Results produced an internally consistent set of item which: (1) loaded on a separate factor from verbal aggressiveness items, (2) contributed unique variance over that accounted for by verbal aggressiveness in the prediction of psychoticism, a theoretically appropriate criterion variable for validating aggression measures, and (3) loaded on the same factor with verbal aggressiveness and psychoticism when second‐order factor analysis was conducted
A “Dark Side” of Communication Avoidance: Indirect Interpersonal Aggressiveness
Although our understanding of direct forms of verbal aggressiveness has been greatly advanced over the past decade, indirect interpersonal aggressiveness has remained relatively understudied. In the present study, items designed to tap indirect forms of interpersonal aggressiveness were written, administered to participants, factor analyzed along with verbal aggressiveness items, and correlated with a criterion measure. Results produced an internally consistent set of item which: (1) loaded on a separate factor from verbal aggressiveness items, (2) contributed unique variance over that accounted for by verbal aggressiveness in the prediction of psychoticism, a theoretically appropriate criterion variable for validating aggression measures, and (3) loaded on the same factor with verbal aggressiveness and psychoticism when second‐order factor analysis was conducted
Effects of 1- and 2-MeV electrons on photomultiplier tubes
Various types of photomultiplier tubes useful for space applications were irradiated with 1- and 2-MeV electrons at Van Allen radiation belt fluxes of 100,000 to 10 millions electrons/sq cm-sec. The increase in the dark current due to electron irradiation was observed at various bias voltages under worst-case conditions (no shielding). Results were presented in the form of dark current plotted against electron flux. All the tubes tested showed extremely large increases in dark current. Tube types 541A, 6217, 6199, and 6903 exhibited the largest increases under irradiation, whereas type 1P22 was affected the least. All the damage observed was transient. The luminescence produced in the optical window probably accounts for a large part of the dark-current increases, but there were some effects possibly due to direct irradiation of the photocathode and dynode chain
From Opportunity to Necessity: Development of an Asynchronous Online Interprofessional Learning Experience
Incorporating interprofessional collaboration competencies into both undergraduate pre-licensure and graduate health science students poses challenges for academic health science centers. Certain student groups may have less opportunity to participate in interprofessional learning experiences due to demands of individual programs of study and conflicts in scheduling time with other disciplines. A group of interprofessional higher education faculty members created an innovative online asynchronous interprofessional experience with the primary goals of meeting accreditation standards for specific programs and providing interprofessional education (IPE) to students who were unable to participate in traditional face-to-face IPE experiences already established at the institution. This guide will highlight the process of design and development of the learning opportunity, from conception to implementation. The pilot of the asynchronous online IPE experience served as a model for the transition of the original in-person model to virtual IPE during the COVID-19 pandemic
The paradox of invasion:Reeves' muntjac deer invade the British Isles from a limited number of founding females
An Empirical Test of a Communibiological Model of Trait Verbal Aggressiveness
The purpose of this study was to test Beatty and McCroskey\u27s communibiological model of trait verbal aggressiveness. In general, this model views trait verbal aggressiveness as an expression of temperament; specifically, that trait verbal aggressiveness represents low thresholds for the fight or flight (FFS) neurobiological system. This model further contends that behavioral inhibition circuitry (BIS) moderates FFS activation by tempering aggressive impulses, otherwise FFS activation would manifest itself in the form of physical rather than verbal attacks. Beatty and McCroskey (1997) propose that low thresholds for stimulating the behavioral activation system (BAS) should be related to trait verbal aggressiveness to the extent that the construct involves a proactive rather than a purely reactive interpersonal function. Because previous research indicated that psychoticism (P), neuroticism (N) and extroversion (E) represent psychological manifestations of the FFS, BIS, and BAS systems, respectively, hypotheses linking P, N, and E to trait verbal aggressiveness (VAS) were tested. A multiple regression equation based on disattenuated correlations explained approximately 46% of the variance in VAS scores. Specifically, (1) the results for P and N were consistent with predictions derived from Beatty and McCroskey\u27s model, and (2) the results for E were indicative of a purely reactive function of trait verbal aggressiveness. Implications for theory and research are discussed
- …