Design and manufacture of a chain driven motor shaft for Formula Electric applications

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (page 23).This document describes the design, manufacture, and testing of a motor shaft assembly that is a subcomponent of the drivetrain system in a Formula Electric racecar. The design covers detailed analysis of the bearing, sprocket, shaft, pins, and spacer created to meet a set of functional requirements. The process of determining these requirements is also covered, along with a set of best practices for thoughtful design in general. An initial phase of testing is covered as well, from the design of the testing apparatus to the execution of a torsional test on the shaft. With limited data, conclusions are hard to draw with certainty, but initial results seem to indicate that the shaft performs as expected. The intent of this document is to serve as an example of the level of detail and thoroughness that is expected when designing racecar components. To that end, this document should provide a number of unique examples of how specific problems were modeled and addressed in the design. It should also serve as a template for future documentation of such design efforts.by Jack J. Wanderman.S.B

WIKIPEDIA PROJECT TO TEACH ACADEMIC WRITING IN AN EAP UNIVERSITY COURSE

The introduction of modern information and communication technologies (ICT) into the classroom has led to a number of challenges and opportunities for instructors across the field of education. Wikipedia, a collaborative encyclopedia, has proven to be one of the most controversial online platforms throughout academia, with many higher education instructors banning its use outright. Despite the prevailing negative attitude, there has been a recent shift in thought among some in the field regarding its utilization as a teaching tool in a number of applications. One popular use is as the centre of a writing project, most commonly the creation of a new article or the improvement of a pre-existing one.This paper outlines a case study conducted at the Latvia University of Life Sciences and Technologies in the autumn semester of 2019, in which first year international veterinarian medicine students wrote Wikipedia articles as part of a semester-long project in an English for academic purposes course in order to improve academic writing skills such as researching, analysing, summarizing, and editing. Analysis of two questionnaires and the students’ work suggest that despite some challenges, a Wikipedia article writing project can serve as an engaging, rewarding, and effective method to teach academic writing skills.

The Effects of Dissolved Oxygen Concentration and Biological Solids Retention Time on Activated Sludge Treatment Performance

A bench scale treatment system with dissolved oxygen (DO) control was used to determine the effects of DO concentration and biological solids retention time (BSRT) on treatment performance using the activated sludge process. The four reactors, operating at BSRTs of 20, 10, 5, and 2 days, were fed settled municipal wastewater collected from the Kuwahee wastewater treatment plant in Knoxville, TN. The DO was maintained at different set points in each reactor ranging from 4.0 to 0.2 mg/L. Experimental results indicate that carbon treatment performance improved, on average, with increasing BSRT but DO had little effect on carbon oxidation. Sludge volume index (SVI) and effluent suspended solids (ESS) values also indicated that BSRT not DO concentration, affected sludge settling. Complete nitrification occurred in the 20, 10, and 5 day BSRT reactors under excess DO conditions ( ³2.0 mg/L). Nitrification was unaffected at a DO as low as 0.5 mg/L for the two longest BSRTs; however, nitrite buildup occurred in the 5 day BSRT during operation at 0.5 mg/L DO suggesting that nitrite oxidation can limit nitrification when insufficient DO is present. A 2 day BSRT was found to be insufficient for complete nitrification at all DO levels. Kinetic coefficients for the nitrifiers were determined for Knoxville’s municipal wastewater. The yield, decay coefficient, maximum substrate utilization rate, maximum growth rate, substrate half saturation coefficient, and oxygen half saturation coefficient were found to be 0.33 mg VSS/mg N, 0.17 day-1, 2.2 mg N/mg VSS-day, 0.75 day-1, 0.25 mg/L NH4+, and 0.92 mg/L O2 respectively. These values are within a published range identified in the literature

A 2-chain can interlock with a k-chain

One of the open problems posed in [3] is: what is the minimal number k such that an open, flexible k-chain can interlock with a flexible 2-chain? In this paper, we establish the assumption behind this problem, that there is indeed some k that achieves interlocking. We prove that a flexible 2-chain can interlock with a flexible, open 16-chain.Comment: 10 pages, 6 figure

Exploring the Problem-Finding and Problem-Solving Approach for Designing Organizations

An emerging problem-finding and problem-solving approach suggests that management's discovering problems to solve, opportunities to seize, and challenges to respond to, are vital to organizations. This paper explores the extent to which the problem-finding and problem-solving approach can provide a foundation for joining the capabilities, dynamic capabilities, and governance perspectives as a way to help scholars and practitioners to coherently design organizations from the perspective of design science. The problem-finding and problem-solving approach offers a unit of analysis and a set of behavioral assumptions that enable us to address open questions within the extant literature and to propose new questions in management research.