27,946 research outputs found
Geological and hydrogeological investigation in West Malaysia
The author has identified the following significant results. The broad synoptic view of the images allowed easy identification of circular features and major fault traces in low lying areas. Sedimentary units were delineated in accordance with the prevailing rock types and where applicable the folding characteristics. Igneous units could easily be differentiated by tone, degree of fracturing, texture, and drainage pattern. The larger fold structures, anticlinoriums and synclinoriums, of the younger sediments on the eastern edge of the central belt could also be easily delineated
Geological and hydrogeological investigations in west Malaysia
The author has identified the following significant results. Large structures along the east coast of the peninsula were discovered. Of particular significance were the circular structures which were believed to be associated with mineralization and whose existence was unknown. The distribution of the younger sediments along the east coast appeared to be more widespread than previously indicated. Along the Pahang coast on the southern end, small traces of raised beach lines were noted up to six miles inland. The existence of these beach lines was unknown due to their isolation in large coastal swamps
Coherent Topological Charge Structure in Models and QCD
In an effort to clarify the significance of the recent observation of
long-range topological charge coherence in QCD gauge configurations, we study
the local topological charge distributions in two-dimensional sigma
models, using the overlap Dirac operator to construct the lattice topological
charge. We find long-range sign coherence of topological charge along extended
one-dimensional structures in two-dimensional spacetime. We discuss the
connection between the long range topological structure found in and
the observed sign coherence along three-dimensional sheets in four-dimensional
QCD gauge configurations. In both cases, coherent regions of topological charge
form along membrane-like surfaces of codimension one. We show that the Monte
Carlo results, for both two-dimensional and four-dimensional gauge theory,
support a view of topological charge fluctuations suggested by Luscher and
Witten. In this framework, the observed membranes are associated with
boundaries between ``k-vacua,'' characterized by an effective local value of
which jumps by across the boundary.Comment: 26 page
An assessment of residents’ and fellows’ personal finance literacy: An unmet medical education need
Objectives: This study aimed to assess residents' and fellows' knowledge of finance principles that may affect their personal financial health. Methods: A cross-sectional, anonymous, web-based survey was administered to a convenience sample of residents and fellows at two academic medical centers. Respondents answered 20 questions on personal finance and 28 questions about their own financial planning, attitudes, and debt. Questions regarding satisfaction with one's financial condition and investment-risk tolerance used a 10-point Likert scale (1=lowest, 10=highest). Of 2,010 trainees, 422 (21%) responded (median age 30 years; interquartile range, 28-33). Results: The mean quiz score was 52.0% (SD = 19.1). Of 299 (71%) respondents with student loan debt, 144 (48%) owed over 25,000. Respondents' mean satisfaction with their current personal financial condition was 4.8 (SD = 2.5) and investment-risk tolerance was 5.3 (SD = 2.3). Indebted trainees reported lower satisfaction than trainees without debt (4.4 vs. 6.2, F (1,419) = 41.57, p < .001). Knowledge was moderately correlated with investment-risk tolerance (r=0.41, p < .001), and weakly correlated with satisfaction with financial status (r=0.23, p < .001). Conclusions: Residents and fellows had low financial literacy and investment-risk tolerance, high debt, and deficits in their financial preparedness. Adding personal financial education to the medical education curriculum would benefit trainees. Providing education in areas such as budgeting, estate planning, investment strategies, and retirement planning early in training can offer significant long-term benefits.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Hydrogen Fuel Cell Pick and Place Assembly Systems: Heuristic Evaluation of Reconfigurability and Suitability
Proton Exchange Membrane Fuel Cells (PEMFCs) offer numerous advantages over combustion technology but they remain economically uncompetitive except for in niche applications. A portion of this cost is attributed to a lack of assembly expertise and the associated risks. To solve this problem, this research investigates the assembly systems that do exist for this product and systematically decomposes them into their constituent components to evaluate reconfigurability and suitability to product. A novel method and set of criteria are used for evaluation taking inspiration from heuristic approaches for evaluating manufacturing system complexity. It is proposed that this can be used as a support tool at the design stage to meet the needs of the product while having the capability to accept potential design changes and variants for products beyond the case study presented in this work. It is hoped this work develops a new means to support in the design of reconfigurable systems and form the foundation for fuel cell assembly best practice, allowing this technology to reduce in cost and find its way into a commercial space
A Framework for Automatically Realizing Assembly Sequence Changes in a Virtual Manufacturing Environment
© 2016 The Authors. Global market pressures and the rapid evolution of technologies and materials force manufacturers to constantly design, develop and produce new and varied products to maintain a competitive edge. Although virtual design and engineering tools have been key to supporting this fast rate of change, there remains a lack of seamless integration between and within tools across the domains of product, process, and resource design-especially to accommodate change. This research examines how changes to designs within these three domains can be captured and evaluated within a component based engineering tool (vueOne, developed by the Automation Systems Group at the University of Warwick). This paper describes how and where data within these tools can be mapped to quickly evaluate change (where typically a tedious process of data entry is required) decreasing lead times and cost and increasing productivity. The approach is tested on a sub-assembly of a hydrogen fuel cell, where an assembly system is modelled and changes are made to the sequence which is translated through to control logic. Although full implementation has not yet been realized, the concept has the potential to radically change the way changes are made and the approach can be extended to supporting other change types provided the appropriate rules and mapping
Searching for Dark Matter at the LHC with a Mono-Z
We investigate a mono-Z process as a potential dark matter search strategy at
the LHC. In this channel a single Z boson recoils against missing transverse
momentum, attributed to dark matter particles, , which escape the
detector. This search strategy is related, and complementary to, monojet and
monophoton searches. For illustrative purposes we consider the process
in a toy dark matter model, where the Z boson is
emitted from either the initial state quarks, or from the internal propagator.
Among the signatures of this process will be a pair of muons with high pT that
reconstruct to the invariant mass of the Z, and large amounts of missing
transverse energy. Being a purely electroweak signal, QCD and other Standard
Model backgrounds are relatively easily removed with modest selection cuts. We
compare the signal to Standard Model backgrounds and demonstrate that, even for
conservative cuts, there exist regions of parameter space where the signal may
be clearly visible above background in future LHC data, allowing either new
discovery potential or the possibility of supplementing information about the
dark sector beyond that available from other observable channels.Comment: 11 pages, 13 figure
A question of hierarchy: matter effects with atmospheric neutrinos and anti-neutrinos
It is by now established that neutrinos mix, have (different) non-zero
masses, and therefore oscillate. The oscillation parameters themselves,
however, are not all well-known. An open problem is that of the neutrino mass
hierarchy. We study the possibility of determining the neutrino mass hierarchy
with atmospheric neutrinos using an iron calorimeter detector capable of charge
identification such as the proposed MONOLITH and ICAL/INO detectors. We find
that such detectors are sensitive to the sign of the mass-squared difference,
\delta_{32} = m_3^2 - m_2^2, provided the as-yet unknown mixing angle between
the first and third generations, \theta_{13}, is greater than 6 degrees (\sin^2
2\theta_{13} > 0.04). A result with a significance greater than 90% CL requires
large exposures (more than 500 kton-years) as well as good energy and angular
resolution of the detected muons (better than 15%), especially for small
\theta_{13}. Hence obtaining definitive results with such a detector is
difficult, unless \theta_{13} turns out to be large. In contrast, such
detectors can establish a clear oscillation pattern in atmospheric neutrinos in
about 150 kton-years, therefore determining the absolute value of \delta_{32}
and \sin^2 2 \theta_{23} to within 10%.Comment: 36 pages revtex with 14 eps figures; new section on statistical
significance when detector resolution is include
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