@article{robichaud_dixon_potturi_cassidy_edwards_sohn_dow_muddiman_2011, title={Design, modeling, fabrication, and evaluation of the air amplifier for improved detection of biomolecules by electrospray ionization mass spectrometry}, volume={300}, ISSN={["1873-2798"]}, DOI={10.1016/j.ijms.2010.04.006}, abstractNote={Through a multi-disciplinary approach, the air amplifier is being evolved as a highly engineered device to improve detection limits of biomolecules when using electrospray ionization. Several key aspects have driven the modifications to the device through experimentation and simulations. We have developed a computer simulation that accurately portrays actual conditions and the results from these simulations are corroborated by the experimental data. These computer simulations can be used to predict outcomes from future designs resulting in a design process that is efficient in terms of financial cost and time. We have fabricated a new device with annular gap control over a range of 50 to 70 μm using piezoelectric actuators. This has enabled us to obtain better aerodynamic performance when compared to the previous design (2× more vacuum) and also more reproducible results. This is allowing us to study a broader experimental space than the previous design which is critical in guiding future directions. This work also presents and explains the principles behind a fractional factorial design of experiments methodology for testing a large number of experimental parameters in an orderly and efficient manner to understand and optimize the critical parameters that lead to obtain improved detection limits while minimizing the number of experiments performed. Preliminary results showed that several folds of improvements could be obtained for certain condition of operations (up to 34 folds).}, number={2-3}, journal={INTERNATIONAL JOURNAL OF MASS SPECTROMETRY}, author={Robichaud, Guillaume and Dixon, R. Brent and Potturi, Amarnatha S. and Cassidy, Dan and Edwards, Jack R. and Sohn, Alex and Dow, Thomas A. and Muddiman, David C.}, year={2011}, month={Mar}, pages={99–107} }
 @article{furst_dow_garrard_sohn_2010, title={Automated Part Centering With Impulse Actuation}, volume={132}, ISSN={["1528-8935"]}, DOI={10.1115/1.4000681}, abstractNote={Centering a part on a spindle for precision machining is a tedious, time-consuming task. Currently, a skilled operator must measure the run-out of a part using a displacement gauge, then tap the part into place using a plastic or rubber hammer. This paper describes a method to automatically center a part on a vacuum chuck with initial run-out as large as 2.5 mm. The method involves measuring the magnitude and direction of the radial run-out and then actuating the part until the part and spindle centerlines are within 5 μm of each other. The run-out can be measured with either a touch probe mounted to a machine axis or an electronic gauge. The part is tapped into place with a linear actuator driven by a voice coil motor. This paper includes an analysis of run-out measurement uncertainty as well as the design, performance modeling, and testing of the alignment actuator. This actuator was employed for part realignment and successfully positioned a hemispherical part with an initial run-out of 1–2.5 mm to within 5 μm of the spindle centerline. This capability shows that the run-out of a part manually placed on flat vacuum chuck can be automatically corrected.}, number={1}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Furst, S. J. and Dow, T. A. and Garrard, K. and Sohn, A.}, year={2010}, month={Feb} }
 @misc{sohn_garrard_dow_2005, title={Polar coordinate-based profilometer and methods}, volume={6,895,682}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Sohn, A. and Garrard, K. P. and Dow, T. A.}, year={2005} }
 @article{balkey_day_batha_elliot_pierce_sandoval_2004, title={Production and metrology of cylindrical inertial confinement fusion targets with sinusoidal perturbations}, volume={45}, ISSN={["1943-7641"]}, DOI={10.13182/FST04-A435}, abstractNote={Abstract Shock waves generated during inertial confinement fusion implosions propagate toward the center of the capsule encountering interfaces between materials with different densities, such as between the ablator and the DT fuel. These interactions are hydrodynamically unstable and the resulting instability causes mixing of the materials at the interface, which is predicted to have detrimental effects on fusion burn. In this experiment, the growth of a single-mode perturbation machined into a radiographically opaque marker layer, driven by a strong shock, is measured during a cylindrically symmetric implosion. These measurements are used to validate simulations and theories of the complex hydrodynamics. Since any perturbation on the marker layer surface will lead to instability growth, precise knowledge of the initial conditions is critical. The targets used in this experiment have up to a 3.0-μm-amplitude, mode 28 (θ = 98 μm) sinusoidal perturbation machined into a 438-μm-outerradius aluminum band with a nominal thickness of 8 μm. The perturbations were machined using a fast-tool servo [B. JARED and T. A. DOW, Precision Engineering Center Annual Report, North Carolina State University, Raleigh NC, p. 123 (1996)] and were metrologized using a linear variable differential transformer [FRANK J. OLIVER, Practical Instrumentation Tranducers, p. 42-45, Hayden Book Company (1971)]. In this paper, the importance of metrology is discussed and is shown to be critical to the interpretation of experimental results.}, number={2}, journal={FUSION SCIENCE AND TECHNOLOGY}, author={Balkey, MM and Day, RD and Batha, SH and Elliot, NE and Pierce, T and Sandoval, DL}, year={2004}, month={Mar}, pages={107–112} }