Modeling a vehicle suspension system as an educational laboratory exercise

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.In order to teach specific mathematical and applicable concepts of modeling a vehicle suspension system to students in the 2.672 class at MIT, a design of a lab apparatus and plan of the procedure for a laboratory exercise featuring the necessary materials was completed. Specifically, the exercise had the goal of teaching providing students with an insight to vehicle suspension systems and the potential for finding an ideal system by varying system parameters. Using a scaled model of a suspension system that can be modeled as a 2nd order differential system with a variable damper, the lab allows students to study different characteristics of the system and learn to apply mathematics and control to the system. The laboratory exercise will feature a scaled suspension system of a standard vehicle with a variable damping and variable oscillatory input force. These conditions will allow students working the exercise create different scenarios and to vary the damping, allowing them to predict and model the system as a 2nd-order differential equation. Analysis indicates that the model will work for the setup and allow for students to predict the behavior of the model vehicle suspension system.by Daniel T. Schultz.S.B

Quantum incompatibility in collective measurements

We study the compatibility (or joint measurability) of quantum observables in a setting where the experimenter has access to multiple copies of a given quantum system, rather than performing the experiments on each individual copy separately. We introduce the index of incompatibility as a quantifier of incompatibility in this multi-copy setting, as well as the notion of compatibility stack representing the various compatibility relations present in a given set of observables. We then prove a general structure theorem for multi-copy joint observables, and use it to prove that all abstract compatibility stacks with three vertices have realizations in terms of quantum observables.Comment: 22 pages, 13 figure

Spacecraft and Propulsion Technician Error

Commercial aviation and commercial space similarly launch, fly, and land passenger vehicles. Unlike aviation, the U.S. government has not established maintenance policies for commercial space. This study conducted a mixed methods review of 610 U.S. space launches from 1984 through 2011, which included 31 failures. An analysis of the failure causal factors showed that human error accounted for 76% of those failures, which included workmanship error accounting for 29% of the failures. With the imminent future of commercial space travel, the increased potential for the loss of human life demands that changes be made to the standardized procedures, training, and certification to reduce human error and failure rates. Several recommendations were made by this study to the FAA\u27s Office of Commercial Space Transportation, space launch vehicle operators, and maintenance technician schools in an effort to increase the safety of the space transportation passengers

Utilization of Paper Mill Primary Sludge

Recyclable fines and filler contribute to approximately one half the primary sludge stream, and is often disposed of instead of utilized to its fullest potential. With successful recovery of the fines and filler from the primary sludge, less raw material will be needed in the production of paper. This will decrease the cost of virgin material and the cost of disposing the sludge, while at the same time decreasing the volume of waste sent to landfills. Primary sludge was collected from a local paper mill and stored at the facilities of Western Michigan University. Solids and ash testing was done on the sludge in order to obtain background knowledge of the sample. Fiber length was performed using the Clark Classifier. Fines and filler material was separated from the primary sludge by means of a laboratory scale sidehill screen implementing a continuous process. After screening, fiber classification and ash tests were performed on both the accepts and the rejects collected. At this point handsheets were made at varying levels of recovered fines and filler material to determine the effects that increased addition levels had on the strength and optical properties of the handsheets. The tests used to evaluate the handsheets were brightness, tear Index, tensile Index, and zero-span tensile. Results showed that recovered fines and filler material can be added up to 10% addition level without significantly affecting the strength and optical properties

A Cajun Tale

Not required for Music Compositio

Optimization and control in bacterial Lag phase

The lag phase of bacterial growth is important from a medical and food safety perspective, but difficult to study due to the low density and metabolic rate of cells. A new study by Alon and colleagues reveals that the gene expression program during early lag phase prioritizes carbon source utilization enzymes over genes responsible for biomass accumulation. This cellular strategy ultimately maximizes growth, making the best long-term use of the new nutrient-rich environment. See research article: http://www.biomedcentral.com/1752-0509/7/13

Source of the optical red-slope in iron-rich meteorites

The relationship between ordinary chondrites and S-type asteroids is an unresolved issue in meteorite science. S-type asteroids exhibit a positively red-sloped spectrum that is interpreted to indicate the presence of elemental iron on the surfaces. The characteristic red-sloped spectrum of iron-rich meteorites is produced by only the specular component of the reflectance. Complex metallic surfaces can be modeled as linear mixtures of specular and nonspecular components. It is the geometry of the metal on a surface and its interaction with surrounding material, rather than the absolute amount of metal, that determine the redness of resulting spectra. In order to distinguish between ordinary chondrite and differentiated parent bodies it is important to understand how regolith processes affect the nature and form of metal on asteroid surfaces