3,861 research outputs found
On a Testing Methodology for the Mechanical Property Assessment of a New Low-Cost Titanium Alloy Derived from Synthetic Rutile
Mechanical property data of a low-cost titanium alloy derived directly from synthetic rutile is reported. A small-scale testing approach comprising consolidation via field-assisted sintering technology, followed by axisymmetric compression testing, has been designed to yield mechanical property data from small quantities of titanium alloy powder. To validate this approach and provide a benchmark, Ti-6Al-4V powder has been processed using the same methodology and compared with material property data generated from thermo-physical simulation software. Compressive yield strength and strain to failure of the synthetic rutile-derived titanium alloy were revealed to be similar to that of Ti-6Al-4V
Seasonal and spatial variability of selected surface water quality parameters in Setiu Wetland, Terengganu, Malaysia
This paper presents the results for surface water quality parameters measured in the Setiu Wetland, on the east coast of Malaysia, which feeds into the southern part of the South China Sea. There are no previous studies dealing with the seasonal and spatial variation of water quality in this area, despite numerous anthropogenic inputs into this ecologically and economically important wetland. The parameters measured were salinity, temperature, dissolved oxygen (DO), pH, biological oxygen demand (BOD) and total suspended solids (TSS). These parameters were sampled monthly from October 2009 to September 2010, during both the wet and dry seasons, at ten sampling stations distributed throughout the area. The physical water quality parameters were measured in situ whilst TSS and BOD were determined using the standard methods. A deterioration of water quality in the Setiu Wetland was observed in areas near agriculture and aquaculture activities. This was expected to be as a result of the use of fertilisers, waste from fish farm food and the waste products of aquaculture. The parameters measured showed lower mean values of surface salinity, temperature, DO, pH and TSS during the wet season relative to the dry season. In contrast, the concentration of BOD was high during the wet season and lowest in the dry season. Results obtained from this study clearly showed the surface physical water quality for the Setiu Wetland was highly influenced by anthropogenic activities and seasonal variation. Therefore, both factors must be considered to move towards proper management of this wetland
Exploring the potential of knowledge brokering to enhance natural resource management : findings from the Catchment Knowledge Exchange project in Victoria
Despite significant efforts in natural resource management (NRM), the environmental condition of Victoria’s catchments is mostly ‘poor to moderate’, and continuing to decline in many places. NRM is a complex undertaking involving social, economic, and environmental objectives, across policy, research, and practice dimensions. It is therefore not easy to ensure that the knowledge required to underpin effective NRM is readily available to practitioners. Knowledge brokering is an emerging approach with the potential to improve knowledge sharing and exchange. While it has attracted attention in other areas of public interest (such as health and information technology), its potential in NRM has received relatively limited attention. This article reports on a Victorian knowledge brokering case study which was a major element in the Catchment Knowledge Exchange project. A key finding is that knowledge brokering is a role that is being undertaken informally, without proper acknowledgement or definition. This raises challenges for knowledge management in the context of NRM. We conclude that the ‘people’ component of knowledge brokering is the driving element, although organisational processes and information technologies are critical in enhancing the effectiveness of knowledge brokers. Demonstrating the benefits of knowledge brokering in terms of the ultimate measure of its contribution towards improving the condition of catchments remains a challenge
Neural Networks for Information Retrieval
Machine learning plays a role in many aspects of modern IR systems, and deep
learning is applied in all of them. The fast pace of modern-day research has
given rise to many different approaches for many different IR problems. The
amount of information available can be overwhelming both for junior students
and for experienced researchers looking for new research topics and directions.
Additionally, it is interesting to see what key insights into IR problems the
new technologies are able to give us. The aim of this full-day tutorial is to
give a clear overview of current tried-and-trusted neural methods in IR and how
they benefit IR research. It covers key architectures, as well as the most
promising future directions.Comment: Overview of full-day tutorial at SIGIR 201
Research fatigue in COVID-19 pandemic and post-disaster research: Causes, consequences and recommendations
Purpose: Research fatigue occurs when an individual or population of interest tires of engaging with research, consequently avoiding further participation. This paper considers research fatigue in the context of the current COVID-19 pandemic, to identify contributory factors and possible solutions for future post-disaster research.
Methodology: We draw on examples from the literature and our own observations from the recruitment and data collection phases of qualitative and quantitative studies, to provide an overview
of possible research fatigue in the current COVID-19 pandemic, with implications for future post disaster research.
Findings: People affected by disasters sometimes receive multiple requests for study participation by separate teams who may not necessarily be coordinating their work. Not keeping participants
informed of the research process or outcomes can lead to disillusionment. Being overburdened with too many research requests and failing to see any subsequent changes following participation may cause individuals to experience research fatigue.
Originality: Guidelines for researchers wishing to reduce the occurrence of research fatigue include ensuring greater transparency within research; sharing of results; and using oversight or gatekeeper bodies to aid coordination. Failure to restrict the number of times that people are asked to participate
in studies risks poor participation rates. This can subsequently affect the quality of information with which to inform policy-makers and protect the health of the public during the COVID-19 pandemic or other public health disasters/emergencies
Theoretical Evaluations of the Fission Cross Section of the 77 eV Isomer of 235-U
We have developed models of the fission barrier (barrier heights and
transition state spectra) that reproduce reasonably well the measured fission
cross section of U from neutron energy of 1 keV to 2 MeV. From these
models we have calculated the fission cross section of the 77 eV isomer of
U over the same energy range. We find that the ratio of the isomer
cross section to that of the ground state lies between about 0.45 and 0.55 at
low neutron energies. The cross sections become approximately equal above 1
MeV. The ratio of the neutron capture cross section to the fission cross
section for the isomer is predicted to be about a factor of 3 larger for the
isomer than for the ground state of U at keV neutron energies. We have
also calculated the cross section for the population of the isomer by inelastic
neutron scattering form the U ground state. We find that the isomer is
strongly populated, and for the cross section
leading to the population of the isomer is of the order of 0.5 barn. Thus,
neutron reaction network calculations involving the uranium isotopes in a high
neutron fluence are likely to be affected by the 77 eV isomer of U.
With these same models the fission cross sections of U and U
can be reproduced approximately using only minor adjustments to the barrier
heights. With the significant lowering of the outer barrier that is expected
for the outer barrier the general behavior of the fission cross section of
Pu can also be reproduced.Comment: 17 pages including 8 figure
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