Flight test results of the Strapdown hexad Inertial Reference Unit (SIRU). Volume 3: Appendices A-G

Results of flight tests of the Strapdown Inertial Reference Unit (SIRU) navigation system are presented. The fault tolerant SIRU navigation system features a redundant inertial sensor unit and dual computers. System software provides for detection and isolation of inertial sensor failures and continued operation in the event of failures. Flight test results include assessments of the system's navigational performance and fault tolerance. Selected facets of the flight tests are also described in detail and include some of the following: (1) flight test plans and ground track plots; (2) navigation residual plots; (3) effects of approximations in navigation algorithms; (4) vibration spectrum of the CV-340 aircraft; and (5) modification of the statistical FDICR algorithm parameters for the flight environment

Flight test results of the Strapdown hexad Inertial Reference Unit (SIRU). Volume 1: Flight test summary

Flight test results of the strapdown inertial reference unit (SIRU) navigation system are presented. The fault-tolerant SIRU navigation system features a redundant inertial sensor unit and dual computers. System software provides for detection and isolation of inertial sensor failures and continued operation in the event of failures. Flight test results include assessments of the system's navigational performance and fault tolerance

Flight test results of the strapdown hexad inertial reference unit (SIRU). Volume 2: Test report

Results of flight tests of the Strapdown Inertial Reference Unit (SIRU) navigation system are presented. The fault tolerant SIRU navigation system features a redundant inertial sensor unit and dual computers. System software provides for detection and isolation of inertial sensor failures and continued operation in the event of failures. Flight test results include assessments of the system's navigational performance and fault tolerance. Performance shortcomings are analyzed

Coaxial inverted geometry transistor having buried emitter

The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed

A study of redundancy management strategy for tetrad strap-down inertial systems

Algorithms were developed that attempt to identify which sensor in a tetrad configuration has experienced a step failure. An algorithm is also described that provides a measure of the confidence with which the correct identification was made. Experimental results are presented from real-time tests conducted on a three-axis motion facility utilizing an ortho-skew tetrad strapdown inertial sensor package. The effects of prediction errors and of quantization on correct failure identification are discussed as well as an algorithm for detecting second failures through prediction

“I Didn’t Want to Make Them Feel Wrong in Any Way”: Preservice Teachers Craft Digital Feedback on Sociopolitical Perspectives in Student Texts

This qualitative multicase analysis investigated the role of “educational niceness” and “neutrality” (e.g., Baptiste, 2008; Bissonnette, 2016) in preservice English teacher feedback on sociopolitical issues in student writing. As part of the field experiences for several ELA methods courses at two universities, one urban and one rural, the teacher-researchers used Google Docs and other technologies (e.g., screencasts and Google Community) to connect preservice teachers (PSTs) with high school writers at a geographical distance so that urban-situated PSTs could mentor rural-situated writers and vice versa. Five methods courses over two semesters served as cases, and 12 PSTs from those courses participated in focus groups. Data included audio recordings of nine focus groups and PSTs’ digital responses to student writing. Using thematic analysis, the authors explored how PSTs responded to sociopolitical perspectives in students’ writing — both engaging them and staying neutral. Although authentic opportunities for responding to student writers supported PSTs’ critical reflection on teaching writing, analysis of PSTs’ responses indicate that such authentic practice may not be sufficient for preparing PSTs to navigate sociopolitical issues and may, in fact, exacerbate PSTs’ impulse to enact educational niceness

“It Doesn’t Feel Like a Conversation”: Digital Field Experiences and Preservice Teachers’ Conceptions of Writing Response

Research shows that preservice English teachers (PSETs) lack opportunities to respond to student writing and that they may view student writing through a deficit lens. To address this need, the authors developed the Writing Mentors (WM) program, a digital field placement that gave PSETs experience providing feedback to high school writers. In this analysis, we examine how PSETs’ views of response were shaped by their digital interactions with high school writers. The challenges of interacting asynchronously created opportunities for PSETs to identify limitations in the mode of communication, propose approaches to providing feedback, and reflect on how teacher feedback can nurture or constrain relationships with students. These findings point to the promise of critical reflection on the disruptive potential of digital feedback for supporting PSTs’ response to student writing

“I Didn’t Want to Make Them Feel Wrong in Any Way”: Preservice Teachers Craft Digital Feedback on Sociopolitical Perspectives in Student Texts

This qualitative multicase analysis investigated the role of “educational niceness” and “neutrality” (e.g., Baptiste, 2008; Bissonnette, 2016) in preservice English teacher feedback on sociopolitical issues in student writing. As part of the field experiences for several ELA methods courses at two universities, one urban and one rural, the teacher-researchers used Google Docs and other technologies (e.g., screencasts and Google Community) to connect preservice teachers (PSTs) with high school writers at a geographical distance so that urban-situated PSTs could mentor rural-situated writers and vice versa. Five methods courses over two semesters served as cases, and 12 PSTs from those courses participated in focus groups. Data included audio recordings of nine focus groups and PSTs’ digital responses to student writing. Using thematic analysis, the authors explored how PSTs responded to sociopolitical perspectives in students’ writing — both engaging them and staying neutral. Although authentic opportunities for responding to student writers supported PSTs’ critical reflection on teaching writing, analysis of PSTs’ responses indicate that such authentic practice may not be sufficient for preparing PSTs to navigate sociopolitical issues and may, in fact, exacerbate PSTs’ impulse to enact educational niceness

Iatrogenic nerve injury in primary and revision reverse total shoulder arthroplasty

INTRODUCTION Iatrogenic nerve injury in orthopedic surgery can impair functional outcomes. During the last years, a steady increase in the number of performed reverse total shoulder arthroplasties has been reported and complications associated with this procedure are continuously described. Neurological complications, however, remain underreported. The aims of this study were to calculate the incidence of iatrogenic nerve injury after primary and revision reverse total shoulder arthroplasty in a large patient cohort, as well as identify associated patient-and surgery-related risk factors. MATERIALS AND METHODS A retrospective review of our institution's internal Reverse Total Shoulder Arthroplasty (RTSA) database from September 2005 to December 2019 was undertaken and 34 patients with iatrogenic nerve injuries were identified, resulting in a neurological complication rate of 2.6%. Group comparisons between patients with nerve injuries (n = 34) and the remaining cohort without nerve injuries (n = 1275) were performed to identify patient- and surgery-related risk factors. RESULTS Of the 34 cases with iatrogenic nerve injury, damage to terminal nerve branches occurred in 21 patients, whereas a brachial plexus lesion was diagnosed in the other 13. Nerve revision surgery was necessary in four patients. At final follow-up 13 patients (45%) had residual motor deficits and 17 (59%) had residual sensory deficits. Higher numbers of previous surgeries of the affected shoulder correlated with subsequent nerve injury (p = 0.035). Operative time was significantly longer in patients, who developed a neurologic deficit, showing a correlation between duration of surgery and occurrence of nerve injury (p = 0.013). Patients with neurologic complications were significantly younger than patients without nerve damage (median 68 vs. 72 years, p = 0.017). CONCLUSIONS In specialists' hands reverse total shoulder arthroplasty is a rather safe procedure regarding the risk of neurologic injury. However, multiple previous surgeries of the affected shoulder increase the risk of neurological complications. Cases with post-operative neurologic compromise are rare and usually recover well, with few patients suffering long-term functional deficits from iatrogenic nerve injury. LEVEL OF EVIDENCE Level III, retrospective cohort study