Engineering transport by concatenated maps

We present a generalized kick rotor model in which the phase of the kick can vary from kick to kick. This additional freedom allows one to control the transport in phase space. For a specific choice of kick-to-kick phases, we predict novel forms of accelerator modes which are potentially of high relevance for future experimental studies

Geophysical and Biological Reconnaissance of Rock Habitats in Western Camden Bay, Beaufort Sea, Alaska

This report presents the results of a 10-day geophysical and biological survey in western Camden Bay, in the Alaskan Beaufort Sea. The primary objective of this survey was to confirm the existence of boulders and cobbles on the seafloor as reported by Barnes (1981, 1982). The survey area extended from the eastern edge of the Canning River (mud flat area) to Kangigivik Point and seaward to the 14m contour line (Fig. 1). A solid boundary of pack ice prevented any survey work seaward of the 14m contour. We had proposed to examine the seabed to the 18m contour.This work was supported by the Bureau of Land Management through an interagency agreement with the National Oceanic and Atmospheric Administration, under which a multiyear program responding to needs of petroleum development of the Alaskan Continental Shelf is managed by the Outer Continental Shelf Environmental Assessment Program (OCSEAP) office

Mass Transfer of Water at Silica Surfaces - Extension of the data base to lower temperatures

In two previous reports we have dealt with the description of the time dependence of the water content at the surface of silicate glass by mass transfer (SWP 73 and SWP 94). Literature measurements in the range of 200°C100°C. Measurements by Helmich&Rauch serve as a basis. A step change in the mass transfer coefficient is found at 200°

Romancelandia on Twitter: Designing a Digital Humanities Research Assignment for First-Year Writing Students

On Facebook, Instagram, and Tumblr, on blogs and Pinterest and Twitter, romance writers have embraced social media as a way to engage with their readers; they also use these platforms to foster community among romance authors, encouraging and promoting each other. This public presence provides a unique opportunity for scholars to witness the dynamics of the romance writing community in action. In Heather’s first-year writing class, Love and American Culture, in the primary goal is to introduce students to academic writing and research. Part of this entails helping students experience the excitement of writing a research paper when the topic is new and the questions are motivated by genuine interest. Heather has been collaborating with Ann, a research librarian, to develop an assignment sequence around original research on romance authors’ public social networks. The project uses Social Feed Manager and textual analysis tools to give students the opportunity to shape their own research questions and study the Twitter feed of the romance author of their choice. In-class activities will help students track down supplemental research and think through the ethical questions raised by studying individuals’ social media accounts. We are excited to be introducing a project the breaks free from the traditional writing program practice of privileging literary analysis (a quite distinctive research genre) as the prototype of academic research. In our presentation, we will discuss the successes and failures of our first semester’s efforts and, we hope, get good ideas on improving the project

Crack-tip models by Irwin and Dugdale for hydroxyl-damaged crack-tip zones

Due to the hydroxyl generation, the silica network ahead of crack tips is damaged. The consequence is a damaged crack-tip zone showing a reduced Young’s modulus. The linear-elastic fracture mechanical treatment by application of stress intensity factors becomes doubtful especially for large zones. In this report, we use a description via well-known models of Elastic-Plastic Fracture Mechanics, namely, the models by Irwin and Dugdale. As an application we compared the results with experimental observations on crack profiles from literature. The computed and observed Crack-Tip Opening Displacements (CTOD) were found to be in good agreement

Validation of the swelling formalism via evaluation of bending moments from literature: Comparison of theoretical predictions and measurements

The volume of silica expands by the hydroxyl generation when silica surfaces react with water. These volume strains are proportional to the mass concentration of the hydroxyl. They were measured by Wiederhorn et al. by evaluating the curvature of disks undergoing this reaction on only one side. The obtained bending moments were found to be proportional to square-root of heat-treatment time. In the present considerations we pay particular attention to global bending moments caused by swelling, which, in contrast to local swelling stresses, do not require assumptions about the type of stress distribution. It can be stated that • The bending moments from disk curvature and hydroxyl measurements via the IR-evaluation procedure by Libowitzky and Rossman are in excellent agreement. • Predictions of moments M based on diffusivities and surface water concentrations by Helmich and Rauch also show good agreement with correlation coefficients R$^2$>0.95. Consequently, we can sufficiently write: M$_{predict}$ = M$_{measured}$