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Characterization of the Deposition Behavior and Changes in Bonding Structures of Hexamethyldisiloxane and Decamethylcyclopentasiloxane Atmospheric Plasma‐Deposited Films
No full textThe plasma deposition behavior of hexamethyldisiloxane (HMDSO) and decamethylcyclopentasiloxane (D5) is investigated for an atmospheric pressure plasma jet. The energy‐deficient and monomer‐deficient domains are revealed by normalized parameters and no significant difference between HMDSO and D5 is observed. The results are supported by Fourier‐transform infrared spectroscopy (FTIR) and X‐ray photoelectron spectroscopy. The data is also evaluated using an Arrhenius‐type equation and an empirical equation reported in the literature, but the correlation is not as good as the normalized parameters. Changes in Si–O–Si bonding arrangements are analyzed by deconvolution of the FTIR absorbance band, showing an increase in porous cage structures with higher normalized energy input
An Optical-based Tecnique to Obtain Operating Deflection Shapes of Structures with Complex Geometries
No full textThe dynamic characteristics of structures are conventionally obtained by exciting the structure using an impulse hammer or a mechanical shaker and measuring the response using uniaxial or multi-axial accelerometers. However, contact-based sensors can mass-load the structure and do not provide full-field data. Hence, obtaining the true dynamics of the structure using conventional sensors can be challenging. That makes test engineers seek different non-contact techniques that can provide full-field data without mass-loading the structure. Recently, stereo-photogrammetry and three-dimensional digital image correlation (3D DIC) have been adopted to collect operating data for structural analysis. These non-contact optical techniques provide a wealth of distributed data over the entire structure. However, the stereo-camera system is limited by the field-of-view of the cameras; a single pair of DIC cameras may not be able to provide deformation data for the entire structure. Hence, it is challenging to obtain the vibration characteristics of the entire structure. In the current work, a multi-view 3D DIC approach is used and validated to predict the vibrational characteristics of an automotive muffler with a complex structure. A pair of DIC cameras travels over the entire structure to capture the deformation of each field of view. The measured data includes the geometry and displacement data, which is later mapped into a global coordinate system. The measured data in the time domain for each field-of-view is transformed to the frequency domain to extract the operational deflection shapes and resonant frequencies for each field of view. The obtained deflection shapes are stitched together in the frequency domain to extract the operating deflection shapes and resonant frequencies of the automotive body panel with a complex structure
In‐situ extraction and impregnation of black walnut husk into polyethylene film using supercritical carbon dioxide with an ethanol modifier
Get PDFWalnuts are commonly cultivated for their kernel, which is a rich source of antioxidant phenolic compounds. The husk likewise contains antioxidant and antimicrobial compounds, but is typically discarded without further processing. Antioxidant compounds are useful in creating active packaging films, but typically decompose at melt extrusion temperatures in polymer processing. Due to carbon dioxide\u27s low critical point and ability to swell polymer films, supercritical carbon dioxide may be used to impregnate phenolic compounds into polymers. For this study, a novel technique is used to simultaneously produce walnut husk extracts and impregnate the extract into polymer films in the same batch extractor using supercritical carbon dioxide with a 15 wt-% ethanol modifier at 60°C at 19.4 MPa. The effect of varying the loading of walnut husk in the extractor upon impregnation mass was evaluated with the impregnation mass of the film increasing with walnut husk loading. It was determined by FTIR, as well as the eduction of the protein cytochrome c, that antioxidant compounds may be extracted from walnut husks and impregnated into low-density polyethylene film (LDPE) by this technique
Keep Forwardiing Path Freshest in VANET via Applying Reinforcement Learning
No full textIn Vehicular Ad Hoc NETworks (VANET), dynamic topology changes of network and inconstant bandwidth make it hard to maintain an end-to-end path to complete long-time stable data transmission. Facing this challenge, researchers have proposed the hybrid routing approach, which tries to combine both the advantages of recalculating route when topology changes and looking up routing table as long as the network topology is relatively stable. However, the existing hybrid routing algorithms can easily cause the blind path problem, meaning a route entry is kept in the routing table without expiration according to the timeout mechanism but it is actually invalid, because the next hop is already unavailable. To address this issue, we propose a Reinforcement learning based Hybrid Routing algorithm (RHR) that can online track the available paths with their status and use packet-carry-on information as real-time feedback to guide routing. RHR keeps the forwarding path always the freshest and thus improves the system performance. Simulation results show that RHR achieves better performance in packet delivery ratio (PDR), roundtrip time (RTT) and overhead than other peers under different scenarios of network scale, request frequency and vehicle velocity
Traction Load, Tong Position, and Head Support Significantly Influence Cervical Spine Loading During Traction
No full textSome cervical dislocation injuries may be acutely treated with traction via Gardner-Wells tongs, which are attached to the skull via two pins. While a variety of techniques have been proposed and utilized in the literature and clinical practice to use the tongs, these techniques have not been methodically studied to confirm how they transmit loads to the cervical spine. The current study investigated the mechanical effect of different traction techniques in a laboratory setting. A 50th male Hybrid anthropomorphic test device was used as a human surrogate to represent an average male in height and weight was modified to represent a patient with a unilateral facet dislocation injury. Electronic sensors at the atlanto-occipital joint recorded the loading delivered to the superior cervical spine by traction loading. Combinations of the following variables were evaluated as traction loads were progressively increased to one-third of body weight: tong pin position in the skull (anterior–posterior and superior–inferior to the recommended neutral position), traction cable angle in the sagittal plane (elevated, horizontal, declined), and presence or absence of an occipital support. Analysis of the cervical axial traction loads showed that the only significant predictor of cervical tension was the magnitude of the traction load. Anterior–posterior changes in the pin positions in the skull significantly influenced the cervical flexion–extension moment and anterior-posterior (AP) shear. The data show that a combined cervical tension, flexion moment, and anterior shear force can be achieved with posteriorly biased pins and a bolster behind the head. Increasing the angle of traction cable increased the cervical flexion moment and anterior shear force. The following variables should be carefully considered when applying cervical traction since they significantly affect cervical loading: magnitude of the hanging traction load, anterior–posterior pin position, use of an occipital bolster, and traction load angle
1/16/2019: Course Change Form BUSN 483
No full textDeletion since this course is being combined with BUSN 482
1/16/2019: Course Change Form MGMT 101
No full textChanges course from BUSN 101-Business Decision Making to MGT 101-Managing Project Teams for Consumer Value Creation. This change supports an emphasis of Project Management that can be better utilized in co-ops early in the curriculum
1/16/2019: Course Change Form MGMT 482
No full textThis course combines BUSN 482 and BUSN 483 into a single comprehensive strategic management course. This change is intended to provide a comprehensive course that serves as a sound foundation in preparation for the Management capstone course entitled MGMT 484, Business Consulting Project, as well as supporting professional success