DSP IMPLEMENTATION OF A DIGITAL NON-LINEAR INTERVAL CONTROL ALGORITHM FOR A QUASI-KEYHOLE PLASMA ARC WELDING PROCESS

The Quasi-Keyhole plasma arc welding (PAW) process is a relatively simple concept, which provides a basis for controlling the weld quality of a subject work piece by cycling the arc current between a static base and variable peak level. Since the weld quality is directly related to the degree of penetration and amount of heat that is generated and maintained in the system, the Non-Linear Interval Control Algorithm provides a methodology for maintaining these parameters within acceptable limits by controlling the arc current based upon measured peak current times. The Texas Instruments TMS320VC5416 DSK working in conjunction with Signalwares AED-109 Data Converter provides a hardware solution to implement this control algorithm. This study outlines this configuration process and demonstrates its validity

The Transit Light Curve project. XIV. Confirmation of Anomalous Radii for the Exoplanets TrES-4b, HAT-P-3b, and WASP-12b

We present transit photometry of three exoplanets, TrES-4b, HAT-P-3b, and WASP-12b, allowing for refined estimates of the systems' parameters. TrES-4b and WASP-12b were confirmed to be "bloated" planets, with radii of 1.706 +/- 0.056 R_Jup and 1.736 +/- 0.092 R_Jup, respectively. These planets are too large to be explained with standard models of gas giant planets. In contrast, HAT-P-3b has a radius of 0.827 +/- 0.055 R_Jup, smaller than a pure hydrogen-helium planet and indicative of a highly metal-enriched composition. Analyses of the transit timings revealed no significant departures from strict periodicity. For TrES-4, our relatively recent observations allow for improvement in the orbital ephemerides, which is useful for planning future observations.Comment: AJ, in press [11 pages]; corrected error in distance to WASP-1

A Review on Suitable Standards for Hybrid Photovoltaic/Thermal Systems

This paper will present an evaluation of the available standards and their considerations when using active-cooled CPV systems, along with an initial assessment of the most appropriate tests, including additional test requirements, for hybrid Photovoltaic-Thermal (PV-T) systems in order to guarantee their long-time electrical and thermal performance

Discovering Biological Roles of Glycosaminoglycans and Protein O-GlcNAcylation Using Chemical Tools

Carbohydrates surround nearly every cell in the human body. Glycosaminoglycans like chondroitin sulfate and heparan sulfate on the cell surface regulate protein ligand engagement and receptor activation to control a variety of biological processes including development, angiogenesis, and neuronal growth. These polysaccharides exert activity through protein binding to their diverse chemical structures. Therefore, the development of methods to tailor glycosaminoglycan populations at the cell surface with defined structures could provide novel approaches to control biological activity. Herein, two new methods to engineer the cell surface glycocalyx with known glycosaminoglycans are reported. Together, these methods provide complementary short- and long-term approaches to change carbohydrate structures at the cell surface and guide neuronal growth and stem cell differentiation. It is also critical to identify unknown protein-carbohydrate interactions that underlie biological phenomena. Studies delineating novel GAG interactions with an orphan receptor and related soluble ligands are reported herein as well as work towards understanding the biological functions of these newly discovered interactions. These results showcase the utility of chemical biology and biochemical tools to discover and modulate various GAG-protein interactions in diverse biological systems. Within the cell, thousands of proteins are modified by O-GlcNAc glycosylation, a process that is uniquely catalyzed by a single transferase and hydrolase pair unlike many other post-translational modifications. O-GlcNAcylation functions in many biological contexts including transcription, translation, proteostasis, and metabolism. Key to understanding its effects on these physiological phenomena is the discovery of O-GlcNAc modification sites. However, due to a number of technical challenges, O-GlcNAc proteomics has not progressed nearly as quickly as phosphoproteomics. Thus, developing new methods to enrich O-GlcNAcylated substrates and map modification sites is critical to unravel the myriad functions of O-GlcNAc. Herein, a labeling approach using a chemically cleavable tag is reported as an improved method to capture and release O-GlcNAcylated substrates. Unlike other methods, the cleavable Dde tag is quantitatively removed under mild, neutral conditions and leaves a minimal residual tag on the O-GlcNAcylated peptide to be analyzed. Moreover, the Dde linker outcompetes a previously used UV-cleavable tag both at the protein and peptide enrichment levels. Together, these results highlight the potential usefulness of this method to illuminate novel roles of O-GlcNAcylation in diverse systems.</p

On the special role of faithfulness constraints in morphology-sensitive phonology: The M-Faithfulness Model

A number of accounts of morpheme boundary-sensitive phonology have been proposed - Stratal OT (Bermúdez-Otero 2013), Coloured Containment (van Oostendorp 2007), Local Constraint Conjunction (Lubowicz 2002). This thesis considers a number of case studies and demonstrates that none among these existing models can account for the range of boundary-sensitive phonological processes which exist. A new model, M-Faithfulness, is presented which can successfully analyze all of these case studies, including those which other models cannot. The M-Faithfulness model includes two crucial points - one, faithfulness constraints may refer to morphological information in the input only, and two, these faithfulness constraints may target non-morpheme-peripheral material. Along these lines, a new constraint family, M-IDENT, is proposed which extends the idea of IDENT constraints to specifically target morpheme-internal information.Master of Art

Simulating hydraulic interdependence between bridges along a river corridor under transient flood conditions

The interactions between rivers, surrounding hydrogeological features, and hydraulic structures such as bridges are not well-established or understood at the network scale, especially under transient conditions. The cascading hydraulic effects of local perturbations up- and downstream of the site of perturbation may have significant, unexpected, and far-reaching consequences, and therefore often cause concern among stakeholders. The up- and downstream hydraulic impacts of a single structural modification may extend much farther than anticipated, especially in extreme events. This work presents a framework and methodology to perform an analysis of interdependent bridge-stream interactions along a river corridor. Such analysis may help prioritize limited resources available for bridge and river rehabilitations, allow better-informed cost/benefit analysis, facilitate holistic design of bridges, and address stakeholder concerns raised in response to planned bridge and infrastructure alterations. The stretch of the Otter Creek from Rutland to Middlebury, VT, is used as a test bed for this analysis. A two-dimensional hydraulic model is used to examine the effects individual structures have on the bridge-stream network, particularly during extreme flood events. Results show that, depending on their characteristics, bridges and roadways may either attenuate or amplify peak flood flows up- and downstream, or have little to no impact at all. Likewise, bridges may or may not be sensitive to any changes in discharge that result from perturbation of existing structures elsewhere within the network. Alterations to structures that induce substantial backwaters may result in the most dramatic impacts to the network, which can be either positive or negative. Structures that do not experience relief (e.g., roadway overtopping) may be most sensitive to network perturbations

Disparity of externalizing the internal architecture of creation

Thesis (S.M. in Art, Culture and Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012."June 2012." Cataloged from PDF version of thesis.Includes bibliographical references (p. 90-92).The completion of any visual work is not an arrival, but furthered from the origin, the inner plane of perspective, which is so readily lent from the context of communicating the seemingly coded space from which I am inspired. The closest visual language within my grasp to elucidate my inquiries and to extend the physical works into a shared plane of seeing is through prose. This exploration of my research through the coupling of visual works, contextualized through the lens of allegory, furthers my understandings to communicate the inconsistencies in visual articulation. The prose in this case will not be treated as a literary work but as an extension of pre-conscious vision around which my practice has centered. When we read, we activate both a consciously aware state and the pre-conscious workings of our memories, this internal plane where perspective can be realized as a special architecture without form. While writing has the potential to motivate all of the senses, I use it in an attempt to restore the concrete to its original state; the internalized presence of its dimension. I am captivated by a kind of site I cannot clearly articulate with words or works, but there is a clarity, which may be revealed through the parallel pursuit that I will here explore. I would like to see this work as a map of multiple dimensions, a set of architectures that together elucidate a whole.by Matthew Everett Lawson.S.M.in Art, Culture and Technolog

Why Do Senior Officers Sometimes Fail in Character? The Leaky Character Reservoir

This article argues senior officers may fail in character because their rate of character development throughout their careers typically decreases as environmental stressors rise. It conceptualizes character as an open system with both gains and leaks over time and integrates existing scholarship on personality and ethical development to create the Leaky Character Reservoir framework, which it then applies to Army officers’ careers. Military leaders will gain a new understanding of character and find specific actions officers, units, and the US Army can undertake to strengthen the character of its senior officers

Sliver® modules - a crystalline silicon technology of the future

A new technique has been devised for the manufacture of thin (<60µm) highly efficient single crystalline solar cells. Novel methods of encapsulating these Sliver® solar cells have also been devised. Narrow grooves are formed through a 1-2mm thick wafer. Device processing (diffusion, oxidation, deposition) is performed on the wafer, so that each of the narrow strips becomes a solar cell. The strips are then detached from the wafer and laid on their sides, which greatly increases the surface area of solar cell that can be obtained from the wafer. Further gains of a factor of two can be obtained by utilising a simple method of static concentration. Large decreases in processing effort (up to 30-fold) and silicon usage (up to 10-fold) per m2 of module are possible. The size, thickness and bifacial nature of the cells create the opportunity for a wide variety of module architectures and applications

The Transit Light Curve Project. VI. Three Transits of the Exoplanet TrES-2

Of the nearby transiting exoplanets that are amenable to detailed study, TrES-2 is both the most massive and has the largest impact parameter. We present z-band photometry of three transits of TrES-2. We improve upon the estimates of the planetary, stellar, and orbital parameters, in conjunction with the spectroscopic analysis of the host star by Sozzetti and co-workers. We find the planetary radius to be 1.222 +/- 0.038 R_Jup and the stellar radius to be 1.003 +/- 0.027 R_Sun. The quoted uncertainties include the systematic error due to the uncertainty in the stellar mass (0.980 +/- 0.062 M_Sun). The timings of the transits have an accuracy of 25s and are consistent with a uniform period, thus providing a baseline for future observations with the NASA Kepler satellite, whose field of view will include TrES-2.Comment: 15 pages, including 2 figures, accepted Ap