199 research outputs found
An extensible product structure model for product lifecycle management in the make-to-order environment
This paper presents a product structure model with a semantic representation technique that make the product structure extensible for developing product lifecycle management (PLM) systems that is flexible for make-to-order environment. In the make-to-order business context, each product could have a number of variants with slightly different constitutions to fulfill different customer requirements. All the variants of a family have common characteristics and each variant has its specific features. A master-variant pattern is proposed for building the product structure model to explicitly represent common characteristics and specific features of individual variants. The model is capable of enforcing the consistency of a family structure and its variant structure, supporting multiple product views, and facilitating the business processes. A semantic representation technique is developed that enables entity attributes to be defined and entities to be categorized in a neutral and semantic format. As a result, entity attributes and entity categorization can be redefined easily with its configurable capability for different requirements of the PLM systems. An XML-based language is developed for semantically representing entities and entity categories. A prototype as a proof-of-concept system is presented to illustrate the capability of the proposed extensible product structure model
Comparison of acid and alkaline hydrogen-bromine fuel cell systems
The Conference abstracts' website is located at https://ecs.confex.com/ecs/224/webprogram/Paper20002.htmlSession - Vanadium Redox Systems 2 and Other Redox Systems 1: abstract no. 1674The hydrogen bromine (H2-Br2) fuel cell system is an attractive system for electrical energy storage because of its high round-trip conversion efficiency, high power density capability, and anticipated low costs. The hydrogen-bromine fuel cell system can be operated in the acid or alkaline modes. The charge and discharge electrode reactions in an acid H2-Br2 fuel cell system are as follows …postprin
Tensile Properties of Martensitic Stainless Steels at Elevated Temperatures
Tensile properties of quenched and tempered martensitic alloys EP-823, HT-9, and 422 were evaluated at temperatures ranging from ambient to 600 °C as a function of three different tempering times. The results indicated that the yield strength, ultimate tensile strength, and the failure strength were gradually reduced with increasing temperature. The ductility parameters were enhanced at elevated temperatures due to increased plastic flow. However, the tempering time did not significantly influence these properties. The evaluation of the fracture surfaces by scanning electron microscopy revealed reduced cracking and dimpled microstructures, indicating enhanced ductility at higher testing temperatures
A Study of Alkaline-Based H2-Br2 and H2-I2 Reversible Fuel Cells
published_or_final_versio
Disruption of Yarrowia lipolytica biofilms by rhamnolipid biosurfactant
BACKGROUND: Yarrowia lipolytica is an ascomycetous dimorphic fungus that exhibits biofilm mode of growth. Earlier work has shown that biosurfactants such as rhamnolipids are efficient dispersants of bacterial biofilms. However, their effectiveness against fungal biofilms (particularly Y. lipolytica) has not been investigated. The aim of this study was to determine the effect of rhamnolipid on a biofilm forming strain of Y. lipolytica. Two chemical surfactants, cetyl-trimethyl ammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) were used as controls for comparison. RESULTS: The methylene blue dye exclusion assay indicated an increase in fungal cell permeability after rhamnolipid treatment. Microtiter plate assay showed that the surfactant coating decreased Y. lipolytica biofilm formation by 50%. Rhamnolipid treatment disrupted pre-formed biofilms in a more effective manner than the other two surfactants. Confocal laser scanning microscopic studies showed that biofilm formation onto glass surfaces was decreased by 67% after sub-minimum inhibitory concentration (sub-MIC) treatment with rhamnolipids. The disruption of biofilms after rhamnolipid treatment was significant (P<0.05) when compared to SDS and CTAB. CONCLUSION: The results indicate a potential application of the biological surfactant to disrupt Y. lipolytica biofilms
Alkaline-based hydrogen bromine fuel cell
The hydrogen bromine (H2-Br2) fuel cell system is an attractive system for electrical energy storage because of its high round-trip conversion efficiency, high power density capability, and anticipated low costs. The hydrogen-bromine fuel cell system can be operated in the acid or alkaline modes as shown by below ...postprin
Interaction-Induced Enhancement of Spin-Orbit Coupling in Two-Dimensional Electronic System
We study theoretically the renormalization of the spin-orbit coupling
constant of two-dimensional electrons by electron-electron interactions. We
demonstrate that, similarly to the factor, the renormalization corresponds
to the enhancement, although the magnitude of the enhancement is weaker than
that for the factor. For high electron concentrations (small interaction
parameter ) the enhancement factor is evaluated analytically within the
static random phase approximation. For large we use an approximate
expression for effective electron-electron interaction, which takes into
account the local field factor, and calculate the enhancement numerically. We
also study the interplay between the interaction-enhanced Zeeman splitting and
interaction-enhanced spin-orbit coupling.Comment: 18 pages, 2 figures, REVTe
Predicting length of stay in head and neck patients who undergo free flap reconstruction
ObjectiveUnderstanding factors that affect postoperative length of stay (LOS) may improve patient recovery, hasten postoperative discharge, and minimize institutional costs. This study sought to (a) describe LOS among head and neck patients undergoing free flap reconstruction and (b) identify factors that predict increased LOS.MethodsA retrospective cohort was performed of 282 head and neck patients with free flap reconstruction for oncologic resection between 2011 and 2013 at a tertiary academic medical center. Patient demographics, tumor characteristics, and surgical and infectious complications were characterized. Multivariable regression identified predictors of increased LOS.ResultsA total of 282 patients were included. Mean age was 64.7 years (SD = 12.2) and 40% were female. Most tumors were located in the oral cavity (53.9% of patients), and most patients underwent radial forearm free flap (RFFF) reconstruction (RFFF—73.8%, anterolateral thigh flap—11.3%, and fibula free flap—14.9%). Intraoperative complications were rare. The most common postoperative complications included nonwound infection (pneumonia [PNA] or urinary tract infection [UTI]) (15.6%) and wound breakdown/fistula (15.2%). Mean and median LOS were 13 days (SD = 7.7) and 10 days (interquartile range = 7), respectively. Statistically significant predictors of increased LOS included flap take back (Beta coefficient [C] = +4.26, P < .0001), in‐hospital PNA or UTI (C = +2.52, P = .037), wound breakdown or fistula (C = +5.0, P < .0001), surgical site infection (C = +3.54, P = .017), and prior radiation therapy (C = +2.59, P = .004).ConclusionSeveral perioperative factors are associated with increased LOS. These findings may help with perioperative planning, including the need for vigilant wound care, optimization of antibiotics prophylaxis, and institution‐level protocols for postoperative care and disposition of free flap patients.Level of Evidence2b; retrospective cohort.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155916/1/lio2410.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155916/2/lio2410_am.pd
Recommended from our members
Ossifying Parotid Carcinoma ex Pleomorphic Adenoma
We present a unique case of an extensively ossified carcinoma ex pleomorphic adenoma (CXPA) in a 76-year-old man with a five-year history of a slowly growing parotid mass. Fine-needle aspiration of the mass was nondiagnostic. A computed tomography (CT) scan of the lesion revealed a well-circumscribed mass with peripheral calcification. Initial pathological analysis suggested a benign parotid mass, but rigorous decalcification revealed noninvasive CXPA. The patient underwent complete resection of the mass and remained disease-free nine months later. Extensive ossification of a seemingly benign parotid mass may mask areas of carcinoma that may progress if left untreated
- …