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Automatic grounding of vague geographic ontology in data
In constructing an ontological theory of a domain such as geography, it is important not only to take account of the vagueness and ambiguity which is inherent in many of the relevant concepts, but also to be able to relate the high-level definitions of the theory to actual sets of data of varying kinds. Any attempt to ignore or remove vagueness and ambiguity risks errors and conflict in the ontological theory with the knowledge of different domain experts, while an inability to ground the theory in real data limits its practical use. We present here a means of structuring such a theory to handle these issues in a principled manner, which lends itself to concrete implementation. We illustrate with reference to several examples from the domain of hydrography
To Seek and Know our Biases: Autoethnography in Missiological Inquiry
Today, Christian mission scholarship widely accepts the historical influence of colonialism on global mission and its impact on colonizing missiology as a scholarly discipline. Therefore, many scholars have been calling for the âdecolonizationâ of Christian mission. This paper seeks to join the call of decolonization by offering a considerate discussion on integrating autoethnography as a research methodology in missiological inquiry. The Paper demonstrates how autoethnography can be an integral methodology for missiological inquiries, namely in the process of de-colonizing and de-westernizing contemporary mission research
Changing Farming Systems â Financial Implications for Farming Businesses
Future prosperity of farming businesses depends not only on immediate prospects, but also on the capability to adapt to changing circumstances. In looking to the future, farm managers need to assess where the current farming system is taking them, and whether changing to an alternative farming system might be more profitable. There are various techniques for assessing the profitability of alternative farming systems, but frequently the cost of transition is overlooked. The financial consequences of transition to a new farming system are assessed for two case study farms using a spreadsheet tool (STEP), developed by the authors. The tool assists farm managers in assessing the risk of transition strategies as well as comparing rotations.Farm Management,
Atmospheric environmental implications of propulsion systems
Three independent studies have been conducted for assessing the impact of rocket launches on the earth's environment. These studies have addressed issues of acid rain in the troposphere, ozone depletion in the stratosphere, toxicity of chemical rocket exhaust products, and the potential impact on global warming from carbon dioxide emissions from rocket launches. Local, regional, and global impact assessments were examined and compared with both natural sources and anthropogenic sources of known atmospheric pollutants with the following conclusions: (1) Neither solid nor liquid rocket launches have a significant impact on the earth's global environment, and there is no real significant difference between the two. (2) Regional and local atmospheric impacts are more significant than global impacts, but quickly return to normal background conditions within a few hours after launch. And (3) vastly increased space launch activities equivalent to 50 U.S. Space Shuttles or 50 Russian Energia launches per year would not significantly impact these conclusions. However, these assessments, for the most part, are based upon homogeneous gas phase chemistry analysis; heterogeneous chemistry from exhaust particulates, such as aluminum oxide, ice contrails, soot, etc., and the influence of plume temperature and afterburning of fuel-rich exhaust products, need to be further addressed. It was the consensus of these studies that computer modeling of interactive plume chemistry with the atmosphere needs to be improved and computer models need to be verified with experimental data. Rocket exhaust plume chemistry can be modified with propellant reformulation and changes in operating conditions, but, based upon the current state of knowledge, it does not appear that significant environmental improvements from propellant formulation changes can be made or are warranted. Flight safety, reliability, and cost improvements are paramount for any new rocket system, and these important aspects cannot be compromised. A detailed environmental cost-benefit-risk analysis must be conducted before any new chemistry or changes in rocket operating conditions should be seriously considered for any future space or defense applications. This paper presents a summary of the results of environmental assessments contained in these independent studies
Multiculture and public parks : researching super-diversity and attachment in public green spaces
Situating itself in encounter and public space debates and borrowing from non-representational theory approaches this paper uses data from the authorsâ two-year ESRC research project to consider how local urban parks can work as sites of routine encounter, mixity and place belonging. The paper explores how parks as green public spaces are not only important as sites of inclusive openness but that the materiality of parks is a key dynamic in affective encounter processes. Parks can work as animators of social interactions, participatory practices and place affinities across ethnic and cultural difference. The paper concludes that the concept of convivial encounter can be extended to incorporate the concept of elective practices - choosing to be in shared public space can generate connective sensibilities which are not necessarily contingent on exchange. In using parks as a lens to examine localities and diversity the paper critically reflects on research practices for understanding and describing heterogeneous formations of multiculture and argues that the projectâs research design and the fieldwork methods present an attempt to carefully and appropriately respond to research with complexly different places and populations
Effects of scan direction and orientation on mechanical properties of laser sintered polyamide-12
In order to understand the impact of layer-wise scanning direction in the Selective Laser Sintering process, test coupons were manufactured for mechanical testing from DuraFormâą Polyamide powder. The effects of laser energy density, varying between 0.003 and 0.024 J/mm2 were examined in test specimens rotated 90Âș through the Z axis. SLS machines do not always facilitate âcross-hatchingâ of layers and therefore orientation has a major influence on part quality. When employed, the cross-hatching technique scans successive layers perpendicularly to the previous. Studying how parts perform with scan lines in a common direction, will assist in the understanding of how SLS parts behave in practice. Results showed that physical density, tensile strength and elongation rose with energy density up to 0.012 J/mmÂČ. This initial rise was due to a continued improvement in particle fusion with increasing energy density. Above 0.012 J/mmÂČ, these properties started to decline at different rates depending on their orientation (scan direction) on the part bed. Specimenâs oriented perpendicularly to the X axis exhibited a greater elongation at the expense of tensile strength, when compared to parallel specimens
An anomaly detector with immediate feedback to hunt for planets of Earth mass and below by microlensing
(abridged) The discovery of OGLE 2005-BLG-390Lb, the first cool rocky/icy
exoplanet, impressively demonstrated the sensitivity of the microlensing
technique to extra-solar planets below 10 M_earth. A planet of 1 M_earth in the
same spot would have provided a detectable deviation with an amplitude of ~ 3 %
and a duration of ~ 12 h. An early detection of a deviation could trigger
higher-cadence sampling which would have allowed the discovery of an Earth-mass
planet in this case. Here, we describe the implementation of an automated
anomaly detector, embedded into the eSTAR system, that profits from immediate
feedback provided by the robotic telescopes that form the RoboNet-1.0 network.
It went into operation for the 2007 microlensing observing season. As part of
our discussion about an optimal strategy for planet detection, we shed some new
light on whether concentrating on highly-magnified events is promising and
planets in the 'resonant' angular separation equal to the angular Einstein
radius are revealed most easily. Given that sub-Neptune mass planets can be
considered being common around the host stars probed by microlensing
(preferentially M- and K-dwarfs), the higher number of events that can be
monitored with a network of 2m telescopes and the increased detection
efficiency for planets below 5 M_earth arising from an optimized strategy gives
a common effort of current microlensing campaigns a fair chance to detect an
Earth-mass planet (from the ground) ahead of the COROT or Kepler missions. The
detection limit of gravitational microlensing extends even below 0.1 M_earth,
but such planets are not very likely to be detected from current campaigns.
However, these will be within the reach of high-cadence monitoring with a
network of wide-field telescopes or a space-based telescope.Comment: 13 pages, 4 figures and 1 table. Accepted for publication in MNRA
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