Sound, Material and Strength Correlation

With a growing amount of manufacturing utilizing 3D printing, there is a correlation between strength and material which can affect sound produced by sirens. An air raid siren that has been downloaded from Thingiverse.com spins with a 49:1 gear ratio to produce 2 tone sounds and with that large number of revolutions comes friction, and in order to create a 3D printed air raid siren, the siren must be made out of a material that can withstand high temperatures without melting and quick rotations without delaminating. There are many materials that can be printed to withstand those forces, but it comes at a cost. In order to maximize sound at the cheapest price there will be different materials for different components depending on the need for heat resistance or strength. With the combination of five materials: PLA, ABS, PETG, PC ISO and ULTEM 9085, the 3D printed air raid siren will be able to maximize sound output without melting or breaking from the extreme forces

Degradation Kinetics and Functional Design of Linear Self-Immolative Polymers

Linear self-immolative polymers display a potential to address many of the limitations in the control over the degradation process in traditional biodegradable polymers. These materials are unique relative to most degradable polymers, in that they undergo end-to-end depolymerization in response to the cleavage of a stabilizing end-capping agent. Although one of their cited attributes is a dependence of their degradation time on chain length, no conclusive study has been conducted to demonstrate and study this effect. Using a previously reported linear self-immolative backbone derived from alternating 4-hydroxybenzyl alcohol and N,N’-dimethylethylenediamine spacers, this work offers the first conclusive study demonstrating the proportional relationship between chain length and degradation time. This is accomplished using a set of monodisperse oligomers synthesized through a new convergent iterative route and a series of polymers optimized to display varying molecular weights. This work also describes the development and validation of a new linear self-immolative degradation model relating monomer kinetics to polymer degradation and shows its application in explaining oligomeric and polymeric degradation profiles. Collectively, this work provides the first quantitative evidence supporting the mixed pseudo zero- and first-order degradation kinetics of linear self-immolative polymers and proves the utility of chain length as an alternate means to tune the degradation time in linear self-immolative polymers. In the second focus of this thesis, a series of modified linear self-immolative amphiphilic block copolymer designs are proposed and evaluated in an effort to develop functional self-immolative nanoparticles for controlled release applications. Overall, the work presented in this thesis serves to expand the utility of linear self-immolative polymers for biomedical applications by demonstrating the flexibility of such systems through controlled design

IMPLOSION DYNAMICS, RADIATION CHARACTERISTICS, AND SPECTROSCOPIC MEASUREMENTS OF WIRE-ARRAY Z-PINCHES ON THE CORNELL BEAM RESEARCH ACCELERATOR (COBRA)

This dissertation presents the results of two experimental studies of wire-array z-pinches on the 1-MA, 100-ns rise-time Cornell Beam Research Accelerator (COBRA). In the first study, results are presented which characterize the implosion dynamics and radiation output of wire array z-pinches on COBRA. Here the load geometries investigated include 10- and 20-mm tall cylindrical arrays ranging from 4 to 16 mm in diameter, and consisting of 8, 16, or 32 wires of either tungsten, aluminum, or Invar (64\% iron, 36\% nickel). Diagnostics fielded include an optical streak camera, a time-gated extreme-ultraviolet framing camera, a laser shadowgraph system, time-integrated pinhole cameras, an x-ray wide-band focusing spectrograph with spatial resolution, an x-ray streak camera, a load voltage monitor, a Faraday cup, a bolometer, silicon diodes, and diamond photoconducting detectors. The data produced by the entire suite of diagnostics are analyzed and presented to provide a detailed picture of the overall implosion process and resulting radiation output on COBRA. The highest x-ray peak powers (300--500 GW) and total energy yields (6--10 kJ) were obtained using 4-mm-diameter arrays that stagnated before peak current. Additional findings include a decrease in soft x-ray radiation prior to stagnation as the initial wire spacing was changed from 1.6 mm to 785 $\mu$m, and a timing correlation between the onset of energetic electrons, hard x-ray generation, and the arrival of trailing current on axis---a correlation that is likely due to the formation of micro-pinches. The details of these and other findings are presented and discussed. In the second study, a new diagnostic setup was developed to record the visible-light spectra emitted from aluminum wire-array plasmas as a continuous function of time. To accomplish this, a half-meter Czerny-Turner spectrometer was used in conjunction with the existing visible light streak camera system. The emitted spectra was seen to consist solely of continuum radiation. This continuum data is now being used to determine electron density. To determine electron density from the continuum data, an absolute calibration of the detection system was required. The details of these experiments, and the absolute calibration technique are presented.This research was partially supported by Sandia National Laboratories Contract No. AO258 and by the Stewardship Science Academic Alliances program of the National Nuclear Security Administration under the Department of Energy Cooperative Agreement No. DE-FC03-02NA00057

Crime, punishment, and evolution in an adversarial game

We examine the game theoretic properties of a model of crime first introduced by Short et al. (2010 Phys. Rev. E 82, 066114) as the SBD Adversarial Game. We identify the rationalizable strategies and one-shot equilibria under multiple equilibrium refinements. We further show that SBD’s main result about the effectiveness of defecting-punishers (“Informants”) in driving the system to evolve to the cooperative equilibrium under an imitation dynamic generalizes to a best response dynamic, though only under certain parameter regimes. The nature of this strategy’s role, however, differs significantly between the two dynamics: in the SBD imitation dynamic, Informants are sufficient but not necessary to achieve the cooperative equilibrium, while under the best response dynamic, Informants are necessary but not sufficient for convergence to cooperation. Since a policy of simply converting citizens to Informants will not guarantee success under best response dynamics, we identify alternative strategies that may help the system reach cooperation in this case, e.g., the use of moderate but not too severe punishments on criminals

How to Write, Edit, and Review Persuasive Briefs: Seven Guidelines from One Judge and Two Lawyers

The ability to write and recognize a persuasive brief is important to lawyers throughout their careers. Junior attorneys are often responsible for initially writing a brief. Senior attorneys often review those briefs and either rewrite or edit them (as circumstances require). In-house counsel may then review the briefs once more, providing additional edits and comments and addressing concerns. Wherever you happen to be in your career, it is important to know how to write, rewrite, edit, recognize, and review an effective brief. This Article offers a number of guidelines for crafting such briefs and provides a number of practical pointers to help lawyers along the way from writing through final review

How to Write, Edit, and Review Persuasive Briefs: Seven Guidelines from One Judge and Two Lawyers

The ability to write and recognize a persuasive brief is important to lawyers throughout their careers. Junior attorneys are often responsible for initially writing a brief. Senior attorneys often review those briefs and either rewrite or edit them (as circumstances require). In-house counsel may then review the briefs once more, providing additional edits and comments and addressing concerns. Wherever you happen to be in your career, it is important to know how to write, rewrite, edit, recognize, and review an effective brief. This Article offers a number of guidelines for crafting such briefs and provides a number of practical pointers to help lawyers along the way from writing through final review