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Handhold location and utilization during bathtub ingress/egress and sit-to-stand tasks : a pilot study
No full textInstallation of grab bars and handholds are recommended to reduce risk of injuries commonly resulting from unsuccessful transfers in the bath/shower/tub. However, few empirical investigations or studies of handhold and grab bar placement are available to guide installation and aging-in-place renovations. This paper presents a pilot experiment that aims to identify the locations where handholds are most utilized during bathtub ingress/egress and sit-to-stand tasks. Nine young volunteers were videotaped while getting in and out of a simulated bathtub alcove that had a grid arrangement of vertical and horizontal handholds spanning the walls. Analysis of the resulting distribution of grasped handholds shows a clear preference for horizontal handholds in specific locations, as well as a consistent utilization of bathtub rims for stand-sit-stand scenarios. Preferred grab bar configurations are discussed in the context of existing standards. Results support the need for further studies to help inform safe installation of grab bars in residential homes, aging-in-place renovations, and hotel chains
A multi-server parallel system with pure space sharing and Markovian arrivals - A Simulation Approach
No full textBusiness Analytics and Intelligence: A Compendium includes articles on advanced data analysis, business analytics, big data and business intelligence for distinguished academicians, practitioners and researchers from academia and industry. It highlights emerging concepts and potential applications in descriptive, predictive and prescriptive analytics fields. The 216 articles presented in the proceedings are from over 425 contributors from academics and industry
Itô formula for mild solutions of SPDEs with Gaussian and non-Gaussian noise and applications to stability properties
No full textWe use Yosida approximation to find an Itô formula for mild solutions { Xx(t), t ≥ 0 }of SPDEs with Gaussianand non-Gaussian coloured noise, the non Gaussian noise being defined through compensated Poisson random measure associated to a Lévy process. The functions to which we apply such Itô formula are in C1,2([0,T]×H), as in the case considered for SDEs in [19]. Using this Itô formula we prove exponential stability and exponential ultimate boundedness properties in mean square sense for mild solutions. We also compare such Itô formula to an Itô formula for mild solutions introduced by Ichikawain [15], and an Itô formula written in terms of the semigroup of the drift operator [6] which we extend before to the non Gaussian case
2016 Draft Statement
No full textA Draft Statement presenting the findings of the recent evaluation by the Engineering Accreditation Commission of ABET
Application of dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry for the determination of oxygenated volatile organic compounds in effluents from the production of petroleum bitumen
No full textWe present a new procedure for the determination of oxygenated volatile organic compounds in samples of postoxidative effluents from the production of petroleum bitumens using dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry. The eight extraction parameters were optimized for 43 oxygenated volatile organic compounds. The detection limits obtained ranged from 0.07 to 0.82 μg/mL for most of the analytes, the precision was good (relative standard deviation below 2.91% at the 5 μg/mL level and 4.75% at the limit of quantification), the recoveries for the majority of compounds varied from 70.6 to 118.9%, and the linear range was wide, which demonstrates the usefulness of the procedure. The developed procedure was used for the determination of oxygenated volatile organic compounds in samples of raw postoxidative effluents and in effluents after chemical treatment. In total, 23 compounds at concentration levels from 0.37 to 32.95 μg/mL were identified in real samples. The same samples were also analyzed in the SCAN mode, which resulted in four more phenol derivatives being identified and tentatively determined. The studies demonstrated the need for monitoring volatile organic compounds content in effluents following various treatments due to the formation of secondary oxygenated volatile organic compounds. This article is protected by copyright. All rights reserved
A procedure for evaluating the applicability of a control proxy function to optimal co-design
No full textOptimisation is a useful tool in the design of many systems. When designing a system which will be subject to control, the full optimisation of the system must take into account both the physical components of the system and the controller. Many different methods have been developed for the optimisation of such systems. One approach is to define one single optimisation objective, which may consist of a combination of system characteristics; another approach iterates between the physical system, or plant, and the controller. Other approaches are sequential, in which the plant is optimised first, followed by the controller. The optimisation of the plant may, in some cases, include some characteristics relevant to the controller. One such sequential method, optimisation using a control proxy function (CPF), is highlighted in this paper. This method allows a designer to perform sequential optimisation of a coupled co-design problem, while producing optimal or near-optimal results. However, it is necessary to first evaluate whether the CPF method is appropriate for a problem, and then to identify an appropriate CPF. This paper presents a decision process which a designer can use to determine whether the CPF approach is appropriate, and if so, criteria to determine the CPF
Assessment of electron swarm parameters and limiting electric fields in SF 6 +CF 4 +Ar gas mixtures
No full textThe electron swarm parameters, namely electron drift velocity, mean energy, effective ionization coefficient and limiting values of number-density-reduced electric fields, E/N, are calculated and assessed in SF6+CF4+Ar ternary mixtures for SF6 concentrations that vary from 1% to 20% over a range of E/N from 50Td to 600Td by solving Boltzmann\u27s equation. The limiting electric field values for the ternary mixtures are deduced from the graphs of the calculated effective ionization coefficients as a function of E/N. Furthermore, breakdown voltage measurements are conducted for the ternary mixtures. The limiting electric field values obtained from the measured breakdown voltages are compared with those of the Boltzmann analysis and found to be in good agreement. The insulation strength of the ternary mixtures with constant Ar concentrations indicated an increase with increasing contents of SF6 while the share of CF4 in the mixture reduced in the investigated E/N range up to 600 Td with SF6 concentrations varying from 1% to 20%. Moreover, a significant synergy is observed due to the non-linear nature of the mixture, and the maximum synergy appears to be around 10% SF6 in the mixtures of this study with fixed Ar concentration. Furthermore, theoretical calculations of breakdown voltages from Boltzmann analysis are found to be in good correlation with the experimental values
Antioxidant Potential of Juglans Nigra, Black Walnut, Husks Extracted Using Supercritical Carbon Dioxide with an Ethanol Modifier
Get PDFThe black walnut, Junglas nigra, is indigenous to eastern North America, and abscission of its fruit occurs around October. The fruit consists of a husk, a hard shell, and kernel. The husk is commonly discarded in processing, though it contains phenolic compounds that exhibit antioxidant and antimicrobial properties. For this study, black walnut husks were extracted using supercritical carbon dioxide with an ethanol modifier. The effects of temperature, ethanol concentration, and drying of walnut husks prior to extraction upon antioxidant potential were evaluated using a factorial design of experiments. The solvent density was held constant at 0.75 g/mL. The optimal extraction conditions were found to be 68°C and 20 wt-% ethanol in supercritical carbon dioxide. At these conditions, the antioxidant potential as measured by the ferric reducing ability of plasma (FRAP) assay was 0.027 mmol trolox equivalent/g (mmol TE/g) for dried walnut husk and 0.054 mmol TE/g for walnut husks that were not dried. Antioxidant potential was also evaluated using the total phenolic content (TPC) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assays and the FRAP assay was found to linearly correlate to the TPC assa
Fostering an Entrepreneurial Mindset in Digital Systems Class through a Producer-Customer Model
No full textWe introduce a Producer-Customer model and use it to add an innovative portion to the “Digital Systems” course materials. In this work, we have developed and tested ten Intellectual Property (IP) cores, real products, which are either defective or improvable. A defective product does not function as it should. An improvable product works in accordance with its specification; however, it has potential for improvement. Two different directions are possible for improvements: performance or area. Students will work in the customer and then producer settings to diagnose and then resolve the issues, respectively. This work is an attempt to fulfill the Kern Entrepreneurial Engineering Network (KEEN) Students Outcomes, hence help instill an entrepreneurial mindset in engineering undergraduates. We have received encouraging evaluations for our innovative work from students
Co3O4 Carbon Nanofiber Mats as Negative Electrodes for Sodium-ion Batteries
No full textCo3O4carbon nanofiber (CNF) mats were synthesized by sol-gel electrospinning and carbonization. The tiny Co3O4nanocrystals (6.27 nm) are homogeneously embedded in CNFs predominantly 150 nm in diameter. When applied as negative electrode for sodium-ion batteries (SIBs), Co3O4-CNF mat delivered an excellent cycling stability with reversible specific capacity of 400 mA h g 1 at 0.5 C until 700 cycles. This impressed cycling performance is attributed to the nanoconfinement of the high capacity Co3O4nanocrystals into one-dimensional CNF network. Such a conductive CNF mat could not only used as buffering matrix to effectively release the mechanical strain originated from the Na ion insertion/ex-traction, but also prevent the aggregation of Co3O4nanocrystals