Potential Use In Design Research Articles

Welding simulation of railway bogie frame side beam: Analyses of residual stresses, clamping forces, distortion and prediction of fatigue S-N curves

This paper presents numerical analyses of a welding simulation of a bogie frame side beam. The simulation is based on an analytical thermal model coupled with a non-linear structural finite element model using shell elements enabling the welding simulation of large structures. The predicted clamping forces, distortions, and residual stresses for different clamping conditions and plate thicknesses are analysed in terms of manufacture. A new fatigue model based on the endurance limit approach is proposed using residual stresses to predict the S-N curves. The predicted S-N curves with the proposed model showed close correlation with the S-N curves for class F and class F2 welds of the BS7608 standard, demonstrating its validity and potential use in design.

Optimal control problems for the Navier–Stokes system coupled with the [formula omitted]-[formula omitted] turbulence model

Optimal control of fluid-dynamics systems has gained attention in the last several years from the scientific community because of its potential use in design of new engineering devices and optimization of existing ones. Many research works have extensively studied the optimal control for the system of Navier–Stokes but the problem of turbulence in these works is usually not taken into account because of the many difficulties arising from the numerical implementation and solution of the optimality system. In this work turbulence is considered by coupling the k-ω two-equation turbulence model with the averaged Navier–Stokes system. The complete optimality system is derived and the existence of a weak solution proven. Some numerical examples are reported.

Benzothiophene Selective Estrogen Receptor Modulators Provide Neuroprotection by a novel GPR30-dependent Mechanism.

The clinical benzothiophene SERM (BT-SERM), raloxifene, was compared with estrogens in protection of primary rat neurons against oxygen-glucose deprivation (OGD). Structure-activity relationships for neuroprotection were determined for a family of BT-SERMs displaying a spectrum of ERα and ERβ binding affinity and agonist/antagonist activity, leading to discovery of a neuroprotective pharmacophore, present in the clinically relevant SERMS, raloxifene and desmethylarzoxifene (DMA), for which submicromolar potency was observed for neuroprotection. BT-SERM neuroprotection did not correlate with binding to ER nor classical ER activity, however, both the neuroprotective SERMs and estrogens were shown, using pharmacological probes, to activate the same kinase signaling cascades. The antiestrogen ICI 182,780 inhibited the actions of estrogens, but not those of BT-SERMs, whereas antagonism of the G-protein coupled receptor, GPR30, was effective for both SERMs and estrogens. Since SERMs have antioxidant activity, ER-independent mechanisms were studied using the classical phenolic antioxidants, BHT and Trolox, and the Nrf2-dependent cytoprotective electrophile, sulforaphane. However, neuroprotection by these agents was not sensitive to GPR30 antagonism. Collectively, these data indicate that the activity of neuroprotective BT-SERMs is GPR30-dependent and ER-independent and not mediated by antioxidant effects. Comparison of novel BT-SERM derivatives and analogs identified a neuroprotective pharmacophore of potential use in design of novel neuroprotective agents with a spectrum of ER activity.

Generalized set propagation operations for concurrent engineering

AbstractThis paper defines a number of general operations that accept arbitrary sets of values for two variables and general relations among three variables and generate a variety of third sets that are useful in design. Although the operations are defined without respect to mathematical or engineering domain, computing these operations depends on the specific mathematical domain, and algorithms are available for only a few domains. Appropriate software could make this complexity transparent to the designer, allowing the same conceptual operations to be used in many contexts. The paper proves a number of useful characteristics of the operations and offers examples of their potential use in design.

Improving full text search performance through textual analysis

The increased availability of full text databases has given rise to a number of retrieval problems, resulting from the ambiguities in natural language. The purpose of this study was to explore the potential of text analysis as a tool in full text search and design improvement. A trial analysis was performed in a selected domain, family history literature, and search and design recommendations were then developed from the findings. The findings included information specific to name searching, along with article length and graphical data. Surprisingly, life event terms (e.g., birth year or marriage state), which are commonly used terms in name searches, occurred in the trial text relevant to less than a third of the sampled persons. This suggests that the higher frequency personal name terms (e.g., the subject's name or father's name) should be searched instead. Differences in male versus female search term patterns also occurred, suggesting gender-specific search strategies. There was a low incidence of pedigree charts in the literature, a finding of potential use in design. All of the findings offered insights into possible gains and losses in using one search or design strategy versus another, with strong evidence provided as to the potential of text analysis in full text search and design improvement.

Devolatilization of polymer melts: Machine geometry and scale factors

AbstractThis study was aimed at comparing vented extruder geometries and identifying scale‐up parameters for melt devolatilization. Data are presented comparing single‐ and corotating twin‐screw extruders for devolatilization of methyl methacrylate from poly(methyl methacrylate), and parameters are identified which characterize dynamic similarity for potential use in design and scale‐up. These parameters include conventional process variables such as temperature, throughput, screw RPM, and degree of fill.