The Space Technology 7 Disturbance Reduction System (ST7-DRS) is a NASA technology demonstration payload that operated from January 2016 through July of 2017 on the European Space Agency's LISA Pathfinder spacecraft. The joint goal of the NASA and ESA missions was to validate key technologies for a future space-based gravitational wave observatory targeting the source-rich milliHertz band. The two primary components of ST7-DRS are a micropropulsion system based on colloidal micro-Newton thrusters (CMNTs) and a control system that simultaneously controls the attitude and position of the spacecraft and the two free-flying test masses (TMs). This paper presents our main experimental results and summarizes the overall the performance of the CMNTs and control laws. We find that the CMNT performance to be consistent with pre-flight predictions, with a measured system thrust noise on the order of 100 nN/ √ Hz in the 1 mHz ≤ f ≤ 30 mHz band. The control system maintained the TM-spacecraft separation with an RMS error of less than 2 nm and a noise spectral density of less than 3 nm/ √ Hz in the same band. Thruster calibration measurements yield thrust values consistent with the performance model and ground-based thrust-stand measurements, to within a few percent. We also report a differential acceleration noise between the two test masses with a spectral density of roughly 3 fm/s 2 / √ Hz in the 1 mHz ≤ f ≤ 30 mHz band, slightly less than twice as large as the best performance reported with the baseline LISA Pathfinder configuration and below the current requirements for the Laser Interferometer Space Antenna (LISA) mission.

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We examined the mental constructs that guide students' expectations for advisor behavior. Through exploratory factor analysis, we identified four factors that underlie students' expectations. Interpretive analysis revealed underlying dimensions reflected by the factors of advisor role and enactment level. Specifically, the first dimension reflected that advisors may be expected to perform as academic and developmental advisor. The second dimension showed a refinement of factors such that each role could be enacted in a generalized or individualized manner. Based on the identified role and enactment level, four constructs were posited to guide students' expectations for advisors: informing, mentoring, guiding, and apprising. Findings suggest that students prefer that advisors display the informing, guiding, and apprising behaviors significantly more than mentoring behaviors. Relative emphasis: * theory, research, practice

This study tested the hypothesis that high writing apprehensive subjects would differ significantly from low writing apprehensive subjects in regard to the writing intensity of their jobs. A random sample of 500 people employed in clerical, technical, secretarial, professional, supervisory, or administrative positions in two midwestern manufacturing firms was studied. A significant difference (p < .05) was seen in the mean writing intensity scores between high apprehensives (n = 96) and low apprehensives (n = 91). This finding suggests that where a lack of writing productivity exists in writing-intensive jobs, managers might explore writing apprehension problems, or at least examine the match between levels of apprehension and writing requirements.