Ultrasonic Imaging Systems

The use of ultrasonic imaging systems for non-destructive evaluation is increasing, with particular interest being paid to research into real time and quasi-real time imaging systems. Photos are shown which were taken using an electronically scanned and focused real time ultrasonic imaging system. The system can be operated with longitudinal waves, shear waves, Rayleigh waves, and lamb waves in the 1.5 MHz to 3.5 MHz frequency range, and has been successfully used on composite materials (boron fiber epoxy on titanium) and on a number of metals (steel, aluminum, and titanium). This system has been operated in both transmission and reflection modes; examples of each are shown

The Self-Taught Marketers Guide to Creating an Annual Report

Objective To produce an easy-to-read, visually appealing, 1-4 page annual report for the University of Maryland, Baltimore’s Health Sciences and Human Services Library (HSHSL). The report should be a mix of interesting statistics, highlights, stories, quotes, and photographs to promote the HSHSL’s annual accomplishments to the campus. Methods We gather all of the stories and statistics we think will be eligible material for the annual report, pulling content and ideas from: newsletters, workshops, blog posts, events, exhibits, and meetings with division and department heads. An annual report committee and visual designer decide upon the top stories and statistics, focusing upon high-impact events, meaningful statistics, and attractive design, images, and photographs to craft the report. We keep in mind that the report is meant to be read by non-librarians, and that the language and messages need to be understandable to our larger campus community.Results This will be our 5th year producing an annual report for the HSHSL. The process has become more streamlined and less time-consuming as we have become familiar with where to source content, design principles, and how to manage space limitations. This has decreased the amount of time it takes to produce the report and the number of iterations we go through before achieving our final product. Additionally, other libraries have been inspired by our designs and created their own colorful Annual Reports based on our layouts and ideas. Conclusions In our next report we plan to include a survey link to try to elicit feedback from our readers. We would like to know if the report was useful to them and if there is other information they would be interested to see in future reports

Efficient Model Learning for Human-Robot Collaborative Tasks

We present a framework for learning human user models from joint-action demonstrations that enables the robot to compute a robust policy for a collaborative task with a human. The learning takes place completely automatically, without any human intervention. First, we describe the clustering of demonstrated action sequences into different human types using an unsupervised learning algorithm. These demonstrated sequences are also used by the robot to learn a reward function that is representative for each type, through the employment of an inverse reinforcement learning algorithm. The learned model is then used as part of a Mixed Observability Markov Decision Process formulation, wherein the human type is a partially observable variable. With this framework, we can infer, either offline or online, the human type of a new user that was not included in the training set, and can compute a policy for the robot that will be aligned to the preference of this new user and will be robust to deviations of the human actions from prior demonstrations. Finally we validate the approach using data collected in human subject experiments, and conduct proof-of-concept demonstrations in which a person performs a collaborative task with a small industrial robot

Electron transport through double quantum dots

Electron transport experiments on two lateral quantum dots coupled in series are reviewed. An introduction to the charge stability diagram is given in terms of the electrochemical potentials of both dots. Resonant tunneling experiments show that the double dot geometry allows for an accurate determination of the intrinsic lifetime of discrete energy states in quantum dots. The evolution of discrete energy levels in magnetic field is studied. The resolution allows to resolve avoided crossings in the spectrum of a quantum dot. With microwave spectroscopy it is possible to probe the transition from ionic bonding (for weak inter-dot tunnel coupling) to covalent bonding (for strong inter-dot tunnel coupling) in a double dot artificial molecule. This review on the present experimental status of double quantum dot studies is motivated by their relevance for realizing solid state quantum bits.Comment: 32 pages, 31 figure