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A Self-Assembled, Silicone Acrylate Coating Formulation and Detection of the Optically Non-Uniform Structure with Reflectance Spectroscopy
No full textA newly synthesized, single-step silicone acrylate formulation cured by conventional radiation produced a reflection spectrum that showed an unusual interference pattern for a single-step coating. The acrylate was prepared by transesterification of silicate oligomer with ω-functionalized acrylic alcohol. The reflectance spectrum was analyzed by means of the Fourier transformation, followed by a separation of variables and constrained conditions. The separation of variables was based on the refractive index as a function of the layer depth, which revealed the coating was non-uniform in refractive index. An interface within the coating was independently observed by microscopy, showing that the coating separated into two layers, supporting the numerical analysis. Although the coating was manufactured by a single-step coating process, the two-layer structure that was formed is normally constructed with multiple coating processes, such as applications of a primer and a top coat. Experiments varying the formulation components show that the new silicone acrylate and an aliphatic di-functional acrylic ester were essential components for the formation of the two-layer structure. Outdoor weathering results are presented after 1 year of testing in Florida and Arizona, which showed better performance than conventional coating systems
Software Framework for VR-Enabled Transcatheter Valve Implantation in Unity
No full textVR navigation systems have emerged as a particularly useful tool for the guidance of minimally invasive surgical procedures to restore the 3D perception of the surgical field and augment the visual information available to the surgical team. Over the past decade, X-ray free VR navigation systems based on Electromagnetic (EM) tracking have been proposed to guide catheter-based minimally invasive surgical procedures, including transcatheter valve implantation, with a reduced intra-procedural radiation exposure and contrast medium injections. One of the major limits of current navigation platforms is the lack or the poor reliability/efficiency of the real-time modeling unit to reproduce the deformations of the cardiovascular anatomy and surgical instruments. In this work we propose an EM navigation platform, with software functionalities, developed using the Unity game engine, to mimic physical behaviors of surgical instruments inside the patient vasculature, handle the interaction between the tools and the anatomical model via collision detection, and (in the next version of the software) deform in real-time the anatomy. Additionally, the technology used (Unity) can allow a seamless integration of AR headset to further improve the ergonomics of the 3D scene visualization
Ages in Reliability and Bio Systems, Interpretations, Control, and Applications
No full textIn this article, we define age and compare ages for objects from two populations by making use of their lifetime distributions. The main purposes of this talk are to propose various definitions, based on relationships between important different but equivalent probability components, which allow tractable use in engineering and humane practice. These definitions admit different meaning important in numerous applications. Respectively, there are various areas of use. Most of the statements and Examples are straightforward consequences of the Definitions. For instance, there are several ways for evaluation of the true age of an object on the background of its population. An approach to the time scaling in the age evaluation based on accelerated testing is offered, using the concept of accumulated total stress. Examples with biological age control similar to reliability age-correcting factor illustrate the theory. We generalize this approach to two-dimensional and multi-dimensional distributions that also may represent life, and sketch areas where this knowledge can be applied
Incorporating Open-source Physical Computing Tools into an Introductory Computational Physics Course
No full textPhysical computing is the building of interactive physical systems by the use of hardware and software to sense and respond to the world. I have introduced open-source physical computing into our introductory computational physics course at Kettering University via the Arduino Uno microcontroller and Arduino C/C++. Based on an Advanced Laboratory Physics Association (ALPhA) workshop on Arduino, I wrote a chapter to introduce students to analog and digital data types, simple digital input and output and analog input, basic programming constructs, rapid prototyping, and the engineering design process. For formative assessment, I required students to record results from exercises in the chapter in a LabArchives electronic laboratory notebook and then provided feedback. For summative assessment, I assessed a report and presentation of a device of the students’ own design to acquire data and perform hardware control. I discuss basic and advanced examples of student work. Based on 5 teams with 10 students over two terms, I have observed that students like to use Arduino and can generally implement their designs into a practical device. In most cases, the final projects indicated mastery of the intended learning objectives
1/16/2019: Course Change Form MGMT 312
No full textThis course introduces the students to systems simulation as a way to analyze complex business issues and problems. These skills are increasingly important in the solution of challenging problems in the increasingly complex business environment
PBX 9502 Gas-Generation
No full textWhen energetic materials are subjected to thermal insult, an event may follow in which the explosive exothermically reacts in an undesirable fashion. This event is known as cookoff, or self-ignition, and understanding how different explosives behave during this event is critical for explosives safety. To further our understanding of how PBX 9502 (95% TATB, 5% Kel-F 800) behaves during cookoff, small scale laboratory experiment were conducted to study the pressure rise created by unconfined samples as they were heated to self-ignition. Collected data included high-speed video of deflagration, sample temperature, a time-lapse of thermal damage and expansion, quasi-static pressure during heating, and the dynamic pressure during cookoff. These data provide evidence that this composition remains impermeable through thermal evolution, until internal void pressure overcomes the mechanical strength of the material and drives macro-scale cracking
