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	<title>School of Computing and Information Science</title>
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	<link>http://umaine.edu/cis</link>
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		<title>Opening for Rank-Open Faculty Position in Spatial Informatics</title>
		<link>http://umaine.edu/cis/2013/04/05/opening-for-rank-open-faculty-position-in-spatial-informatics/</link>
		<comments>http://umaine.edu/cis/2013/04/05/opening-for-rank-open-faculty-position-in-spatial-informatics/#comments</comments>
		<pubDate>Fri, 05 Apr 2013 15:35:16 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Department News]]></category>
		<category><![CDATA[News]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1619</guid>
		<description><![CDATA[The School of Computing and Information Science together with the National Center for Geographic Information and Analysis (NCGIA) at the University of Maine seek applicants for an open rank academic-year tenure line joint faculty appointment effective September 1, 2013 with research foci in the area of spatial informatics. The School is an interdisciplinary unit encompassing [...]]]></description>
				<content:encoded><![CDATA[<p>The School of Computing and Information Science together with the National<br />
Center for Geographic Information and Analysis (NCGIA) at the University of<br />
Maine seek applicants for an open rank academic-year tenure line joint<br />
faculty appointment effective September 1, 2013 with research foci in the<br />
area of spatial informatics. The School is an interdisciplinary unit<br />
encompassing Computer Science and Spatial Informatics and offering degrees<br />
in Computer Science (BS, MS, PhD) and Spatial Information Science and<br />
Engineering (MS, PhD). The National Center for Geographic Information and<br />
Analysis is an organized research unit and leading research center in the<br />
area of Geographic Information Science with goals towards advancing major<br />
research innovations in spatial informatics and increasing the supply of PhD<br />
level students trained in spatial information science and engineering.</p>
<p>The successful candidate is required to contribute to the research agenda of<br />
NCGIA, to  advise and mentor graduate students in the Spatial Information<br />
Science and Engineering graduate program, and to teach in the School&#8217;s<br />
academic programs. Spatial Informatics lies at the intersection of software<br />
systems for databases, sensor systems, artificial intelligence,<br />
human-computer interaction, information retrieval, and the semantic web and<br />
deals with methods for modeling, storing, retrieving, analyzing, and<br />
interacting with spatial information.  Core topics within Spatial<br />
Informatics include spatial database systems, spatial reasoning, spatial<br />
robotics, spatial analytics, geosensor networks, multimodal spatial<br />
information processing, and the ethics of geospatial technologies. The<br />
school seeks a candidate with research interests enhancing or complimentary<br />
to its current research strengths in these areas. Any aspect of research<br />
expertise in Spatial Informatics would be considered but research interest<br />
and expertise in the following areas are preferred: spatial cognition,<br />
spatial semantics, spatial linguistics, mobile and ubiquitous computing and<br />
visual analytics.</p>
<p>Applicants must be committed to research excellence, graduate and<br />
undergraduate teaching and have successful experience in securing external<br />
funding. A Ph.D. in computer science, information science, or a related<br />
discipline is required by date of hire.  Academic rank and tenure status<br />
will be commensurate with qualifications and experience.  Applicants must be<br />
available to start work on September 1, 2013.  The position is part of a<br />
Maine Economic Improvement Fund initiative to further invest in Information<br />
Technology. The University of Maine is a land grant institution and the<br />
teaching, research, and service responsibilities of the selected candidate<br />
will be consistent with the land grant mission.</p>
<p>To apply:  Submit a cover letter, curriculum vitae, copies of graduate<br />
academic transcripts, and statements of both research and teaching interests<br />
to Professor Kate Beard, Director, National Center for<br />
Geographic Information and Analysis, School of Computing and Information<br />
Science, 5711 Boardman Hall (Room 348) University of Maine, Orono, ME<br />
04469-5711 with electronic copy to <a href="mailto:beard@spatial.maine.edu">beard@spatial.maine.edu</a>. In addition,<br />
applicants should arrange for three letters of recommendation to be sent by<br />
separate cover.  Review of applications will begin immediately and continue<br />
until the position is filled.  Incomplete applications cannot be considered.<br />
Appropriate background checks will be required.</p>
<p>On January 1, 2011, UMaine became a tobacco-free campus.  Information<br />
regarding UMaine&#8217;s tobacco-free policy is online at<br />
<a href="http://umaine.edu/tobaccofree/">http://umaine.edu/tobaccofree/</a>.</p>
<p>The University of Maine, an EO/AA employer, seeks to employ outstanding<br />
people who contribute to the rich cultural diversity expected in a<br />
university setting.  All qualified individuals are encouraged to apply.</p>
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		<item>
		<title>CIS graduate students successful at UMaine’s GradExpo</title>
		<link>http://umaine.edu/cis/2013/04/05/cis-graduate-students-successful-at-umaines-gradexpo/</link>
		<comments>http://umaine.edu/cis/2013/04/05/cis-graduate-students-successful-at-umaines-gradexpo/#comments</comments>
		<pubDate>Fri, 05 Apr 2013 15:33:42 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Department News]]></category>
		<category><![CDATA[News]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1660</guid>
		<description><![CDATA[Six graduate students from the various graduate programs in the School of Computing and Information Science participated in this year’s GradExpo, among them three winners. Congratulations to all participants! &#160; Posters &#160; Stacy Doore and Janet Nichols: Movement Matters: Using state longitudinal mobility data to improve school policy, intervention and academic outcomes First place in [...]]]></description>
				<content:encoded><![CDATA[<p>Six graduate students from the various graduate programs in the School of Computing and Information Science participated in this year’s <a title="GradExpo" href="http://www2.umaine.edu/gsg/grad-expo/">GradExpo</a>, among them three winners. Congratulations to all participants!</p>
<p>&nbsp;</p>
<p><em>Posters </em></p>
<p>&nbsp;</p>
<p>Stacy Doore and Janet Nichols: Movement Matters: Using state longitudinal mobility data to improve school policy, intervention and academic outcomes</p>
<p><strong>First place in humanities/social sciences poster competition</strong><strong></strong></p>
<p>&nbsp;</p>
<p>Chris Bennett, Non-Visual Graphical Accessibility</p>
<p><strong>Third place in humanities/social sciences poster competition</strong></p>
<p>&nbsp;</p>
<p>Pathum Mudannayake: Semantic Topological Change</p>
<p>&nbsp;</p>
<p>RJ Perry: Data visualization of the Earths Radiation Balance</p>
<p>&nbsp;</p>
<p>Hari Prasath Palani: Accessible Graphics for Visually-Impaired People Using Touch-Based Devices</p>
<p>&nbsp;</p>
<p><em>Oral Presentations</em></p>
<p>&nbsp;</p>
<p>Hegnshan Li: Evaluating the effect of 2D and 3D indoor interfaces for facilitating navigation of multi-level buildings</p>
<p>&nbsp;</p>
<p>Hari Prasath Palani: Accessible Graphics for Visually-Impaired People Using Touch-Based Devices</p>
<p><strong>Winner of the Foster Center for Student Innovation Commercialization Award in Science and Technology</strong></p>
]]></content:encoded>
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		<item>
		<title>Increasing the Scalability of PISM for High Resolution Ice Sheet Models</title>
		<link>http://umaine.edu/cis/2013/02/22/increasing-the-scalability-of-pism-for-high-resolution-ice-sheet-models/</link>
		<comments>http://umaine.edu/cis/2013/02/22/increasing-the-scalability-of-pism-for-high-resolution-ice-sheet-models/#comments</comments>
		<pubDate>Fri, 22 Feb 2013 20:11:06 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1649</guid>
		<description><![CDATA[P. Dickens and T. Morey (2013), Increasing the Scalability of PISM for High Resolution Ice Sheet Models, 14th IEEE International Workshop on Parallel and Distributed Scientific and Engineering Computing (PDSEC-14), Boston, MA. Abstract The issue of global climate change is of great interest to scientist and a critical concern of society at large. One important piece of the [...]]]></description>
				<content:encoded><![CDATA[<p>P. Dickens and T. Morey (2013), <a href="http://www.umcs.maine.edu/~dickens/pubs/Scalability.PISM.pdf">Increasing the Scalability of PISM for High Resolution Ice Sheet Models</a>, <em>14th IEEE International Workshop on Parallel and Distributed Scientific and Engineering Computing (PDSEC-14)</em>, Boston, MA.</p>
<div></div>
<div><span style="font-family: tahoma, 'new york', times, serif">Abstract</span></div>
<div>
<p><span style="font-family: tahoma, 'new york', times, serif">The issue of global climate change is of great interest to scientist and a critical concern of society at large. One important piece of the climate puzzle is how the dynamics of large-scale ice sheets, such as those in Greenland and Antarctic, will react in response to such climate change. Domain scientists have developed several simulation models to predict and understand the behavior of large-scale ice sheets, but the depth of knowledge gained from such models is largely dependent upon the resolution at which they can be efficiently executed. The problem, however, is that relatively small increases in the resolution of the model result in very large increases in the size of the input and output data sets, and an explosion in the number of grid points that must be considered by the simulation. Thus increasing the resolution of ice-sheet models, in general, requires the use of supercomputing technologies and the application of tools and techniques developed within the high-performance computing research community. In this paper, we discuss our work in evaluating and increasing the performance of the Parallel Ice Sheet Model  (PISM) [6, 25, 38], using a high-resolution model of the Greenland ice sheet, on a state-of-the-art supercomputer. In particular, we found that the computation performed by PISM was highly scalable, but that he I/O demands of the higher-resolution model were a significant drag on overall performance. We then performed a series of experiments to determine the cause of the relatively poor I/O performance and how such performance could be improved. By making simple changes to the PISM source code and one of the I/O libraries used by PISM we were able to provide an 8-fold increase in I/O performance.</span></p>
<div><em><span style="font-family: tahoma, 'new york', times, serif"><br />
</span></em></div>
</div>
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		</item>
		<item>
		<title>LocalAlert: Simulating decentralized ad-hoc collaboration in emergency situations</title>
		<link>http://umaine.edu/cis/2013/02/21/localalert-simulating-decentralized-ad-hoc-collaboration-in-emergency-situations/</link>
		<comments>http://umaine.edu/cis/2013/02/21/localalert-simulating-decentralized-ad-hoc-collaboration-in-emergency-situations/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:40:11 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1641</guid>
		<description><![CDATA[S. Nittel, C. Dorr, and J.C. Whittier, 2012, LocalAlert: Simulating decentralized ad-hoc collaboration in emergency situations, in: N.Xioa, M.P. Kwan, M. Goodchild, and S. Shekhar (eds.), Geographic Information Science — Seventh International Conference, GIScience 2012, Columbus, OH, Lecture Notes in Computer Science, Vol. 7478, Springer, pp. 146-159. &#160; Abstract Today, advances in short-range ad-hoc communication and mobile phone [...]]]></description>
				<content:encoded><![CDATA[<p>S. Nittel, C. Dorr, and J.C. Whittier, 2012, <a href="www.spatial.maine.edu/~nittel/papers/GISc2012_LocalAlert_nittel.pdf">LocalAlert: Simulating decentralized ad-hoc collaboration in emergency situations</a>, in: N.Xioa, M.P. Kwan, M. Goodchild, and S. Shekhar (eds.), <em>Geographic Information Science — Seventh International Conference, GIScience 2012</em>, Columbus, OH, <em>Lecture Notes in Computer Science</em>, Vol. 7478, Springer, pp. 146-159.</p>
<p>&nbsp;</p>
<p>Abstract</p>
<p>Today, advances in short-range ad-hoc communication and mobile phone technologies allow people to engage in ad-hoc collaborations based solely on their spatial proximity. These technologies can also be useful to enable a form of timely, self-organizing emergency response. Information about emergency events such as a fire, an accident or a toxic spill is most relevant to the people located nearby, and these people are likely also the first ones to encounter such emergencies. In this paper we explore the concept of decentralized ad-hoc collaboration across a range of emergency scenarios, its feasibility, and potentially effective communication protocols. We introduce the <em>LocalAlert</em> framework, an open source agent simulation framework that we have developed to build and test various form s of decentralized ad-hoc collaboration in different emergency situations. Initial experiments identify a number of parameters that affect the likelihood of a successful response under such scenarios.</p>
<p>&nbsp;</p>
]]></content:encoded>
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		</item>
		<item>
		<title>Spatial reasoning with augmented points: Extending cardinal directions with local distances</title>
		<link>http://umaine.edu/cis/2013/02/21/spatial-reasoning-with-augmented-points-extending-cardinal-directions-with-local-distances/</link>
		<comments>http://umaine.edu/cis/2013/02/21/spatial-reasoning-with-augmented-points-extending-cardinal-directions-with-local-distances/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:34:05 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1637</guid>
		<description><![CDATA[R. Moratz and J.O. Wallgrün, 2012, Spatial reasoning with augmented points: Extending cardinal directions with local distances, Journal of Spatial Information Science, Vol. 5. Abstract We present an approach for supplying existing qualitative direction calculi with a distance component to support fully fledged positional reasoning. The general underlying idea of augmenting points with local reference [...]]]></description>
				<content:encoded><![CDATA[<p>R. Moratz and J.O. Wallgrün, 2012, <a href="http://www.josis.org/index.php/josis/article/view/84/89">Spatial reasoning with augmented points: Extending cardinal directions with local distances</a>, <em>Journal of Spatial Information Science</em>, Vol. 5.</p>
<p>Abstract</p>
<p>We present an approach for supplying existing qualitative direction calculi with a distance component to support fully fledged positional reasoning. The general underlying idea of augmenting points with local reference properties has already been applied in the OPRAm calculus. In this existing calculus, point objects are attached with a local reference direction to obtain oriented points and able to express relative direction using binary relations. We show how this approach can be extended to attach a granular distance concept to direction calculi such as the cardinal direction calculus or adjustable granularity calculi such as OPRAm or the Star calculus. We focus on the cardinal direction calculus and extend it to a multi-granular positional calculus called EPRAm. We provide a formal specification of EPRAm including a composition table for EPRA2 automatically determined using real algebraic geometry. We also report on an experimental performance analysis of EPRA2 in the context of a topological map-learning task proposed for benchmarking qualitative calculi. Our results confirm that our approach of adding a relative distance component to existing calculi improves the performance in realistic tasks when using algebraic closure for consistency checking.</p>
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		</item>
		<item>
		<title>Qualitative Reasoning about Relative Direction of Oriented Points</title>
		<link>http://umaine.edu/cis/2013/02/21/1634/</link>
		<comments>http://umaine.edu/cis/2013/02/21/1634/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:30:16 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1634</guid>
		<description><![CDATA[T. Mossakowski and R.  Moratz, 2012, Qualitative Reasoning about Relative Direction of Oriented Points. Artificial Intelligence Journal, Volumes 180-181, pages 34-45. &#160; Abstract &#160; An important issue in qualitative spatial reasoning is the representation of relative directions. In this paper we present simple geometric rules that enable reasoning about the relative direction between oriented points. This framework, [...]]]></description>
				<content:encoded><![CDATA[<p>T. Mossakowski and R.  Moratz, 2012, <a href="http://www.informatik.uni-bremen.de/~till/papers/OPRA.pdf">Qualitative Reasoning about Relative Direction of Oriented Points</a>. <em>Artificial Intelligence Journal</em>, Volumes 180-181, pages 34-45.</p>
<p>&nbsp;</p>
<p>Abstract</p>
<p>&nbsp;</p>
<p>An important issue in qualitative spatial reasoning is the representation of relative directions. In this paper we present simple geometric rules that enable reasoning about the relative direction between oriented points. This framework, the oriented point algebra OPRA<sub><strong>m</strong></sub>, has a scalable granularity <strong>m</strong>. We develop a simple algorithm for computing the OPRA<sub><strong>m</strong></sub> composition tables and prove its correctness. Using a composition table, algebraic closure for a set of OPRA<sub><strong>m</strong></sub> statements is very useful to solve spatial navigation tasks. It turns out that scalable granularity is useful in these navigation tasks.</p>
<p>&nbsp;</p>
]]></content:encoded>
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		<title>Spatial working memory for locations specified by vision and audition: testing the amodality hypothesis</title>
		<link>http://umaine.edu/cis/2013/02/21/spatial-working-memory-for-locations-specified-by-vision-and-audition-testing-the-amodality-hypothesis/</link>
		<comments>http://umaine.edu/cis/2013/02/21/spatial-working-memory-for-locations-specified-by-vision-and-audition-testing-the-amodality-hypothesis/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:20:20 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1632</guid>
		<description><![CDATA[J.M. Loomis , R.L. Klatzky, B. McHugh, and N.A. Giudice, 2012, Spatial working memory for locations specified by vision and audition: testing the amodality hypothesis, Attention, Perception, &#38; Psychophysics 74(6):1260-7. Abstract Spatial working memory can maintain representations from vision, hearing, and touch, representations referred to here as spatial images. The present experiment addressed whether spatial images from vision [...]]]></description>
				<content:encoded><![CDATA[<p>J.M. Loomis , R.L. Klatzky, B. McHugh, and N.A. Giudice, 2012, Spatial working memory for locations specified by vision and audition: testing the amodality hypothesis, <em>Attention, Perception, &amp; Psychophysics</em> 74(6):1260-7.</p>
<p>Abstract<br />
Spatial working memory can maintain representations from vision, hearing, and touch, representations referred to here as spatial images. The present experiment addressed whether spatial images from vision and hearing that are simultaneously present within working memory retain modality-specific tags or are amodal. Observers were presented with short sequences of targets varying in angular direction, with the targets in a given sequence being all auditory, all visual, or a sequential mixture of the two. On two thirds of the trials, one of the locations was repeated, and observers had to respond as quickly as possible when detecting this repetition. Ancillary detection and localization tasks confirmed that the visual and auditory targets were perceptually comparable. Response latencies in the working memory task showed small but reliable costs in performance on trials involving a sequential mixture of auditory and visual targets, as compared with trials of pure vision or pure audition. These deficits were statistically reliable only for trials on which the modalities of the matching location switched from the penultimate to the final target in the sequence, indicating a switching cost. The switching cost for the pair in immediate succession means that the spatial images representing the target locations retain features of the visual or auditory representations from which they were derived. However, there was no reliable evidence of a performance cost for mixed modalities in the matching pair when the second of the two did not immediately follow the first, suggesting that more enduring spatial images in working memory may be amodal.</p>
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		<item>
		<title>Mid-latitude Amazonian glaciation on Mars</title>
		<link>http://umaine.edu/cis/2013/02/21/mid-latitude-amazonian-glaciation-on-mars/</link>
		<comments>http://umaine.edu/cis/2013/02/21/mid-latitude-amazonian-glaciation-on-mars/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:14:14 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1630</guid>
		<description><![CDATA[J L Fastook and J W Head, 2012, &#8220;&#62;Mid-latitude Amazonian glaciation on Mars: Controls on accumulation and glacial flow patterns, Lunar and Planetary Science Conference XXXXIII, Houston TX. Abstract A model of flow into a crater from episodic layering events driven by obliquity demonstrates that even at Amazonian temperatures, concentric crater fill can be formed in [...]]]></description>
				<content:encoded><![CDATA[<p>J L Fastook and J W Head, 2012, <a href="http://www.lpi.usra.edu/meetings/lpsc2012/pdf/1296.pdf">&#8220;&gt;Mid-latitude Amazonian glaciation on Mars: Controls on accumulation and glacial flow patterns</a>, <em>Lunar and Planetary Science Conference XXXXIII</em>, Houston TX.</p>
<p>Abstract</p>
<p>A model of flow into a crater from episodic layering events driven by obliquity demonstrates that even at Amazonian temperatures, concentric crater fill can be formed in as little as 50 m.y., whereas flow from a single persistent layer takes 450 m.y.</p>
]]></content:encoded>
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		</item>
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		<title>Early Mars climate near the Noachian–Hesperian boundary</title>
		<link>http://umaine.edu/cis/2013/02/21/early-mars-climate-near-the-noachian-hesperian-boundary/</link>
		<comments>http://umaine.edu/cis/2013/02/21/early-mars-climate-near-the-noachian-hesperian-boundary/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:06:56 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1627</guid>
		<description><![CDATA[J L Fastook, J W Head, D R Marchant, F Forget, and J-B Madeleine, 2012, Early Mars climate near the Noachian–Hesperian boundary: Independent evidence for cold conditions from basal melting of the south polar ice sheet (Dorsa Argentea Formation) and implications for valley network formation, Icarus 219(1):  25-40. &#160; Currently, and throughout much of the Amazonian, the mean annual [...]]]></description>
				<content:encoded><![CDATA[<p>J L Fastook, J W Head, D R Marchant, F Forget, and J-B Madeleine, 2012, Early Mars climate near the Noachian–Hesperian boundary: Independent evidence for cold conditions from basal melting of the south polar ice sheet (Dorsa Argentea Formation) and implications for valley network formation, <em>Icarus</em> 219(1):  25-40.</p>
<p>&nbsp;</p>
<p>Currently, and throughout much of the Amazonian, the mean annual surface temperatures of Mars are so cold that basal melting does not occur in ice sheets and glaciers and they are cold-based. The documented evidence for extensive and well-developed eskers (sediment-filled former sub-glacial meltwater channels) in the south circumpolar Dorsa Argentea Formation is an indication that basal melting and wetbased glaciation occurred at the South Pole near the Noachian–Hesperian boundary. We employ glacial accumulation and ice-flow models to distinguish between basal melting from bottom-up heat sources (elevated geothermal fluxes) and top-down induced basal melting (elevated atmospheric temperatures warming the ice). We show that under mean annual south polar atmospheric temperatures (<strong></strong>100 <strong></strong>C) simulated in typical Amazonian climate experiments and typical Noachian–Hesperian geothermal heat fluxes (45–65 mW/m2), south polar ice accumulations remain cold-based. In order to produce significant basal melting with these typical geothermal heat fluxes, the mean annual south polar atmospheric temperatures must be raised from today’s temperature at the surface (<strong></strong>100 <strong></strong>C) to the range of <strong></strong>50 to <strong></strong>75 <strong></strong>C. This mean annual polar surface atmospheric temperature range implies lower latitude mean annual temperatures that are likely to be below the melting point of water, and thus does not favor a &#8220;warm and wet&#8221; early Mars. Seasonal temperatures at lower latitudes, however, could range above the melting point of water, perhaps explaining the concurrent development of valley networks and open basin lakes in these areas. This treatment provides an independent estimate of the polar (and non-polar) surface temperatures near the Noachian–Hesperian boundary of Mars history and implies a cold and relatively dry Mars climate, similar to the Antarctic Dry Valleys, where seasonal melting forms transient streams and permanent ice-covered lakes in an otherwise hyperarid, hypothermal climate.</p>
<p><a href="http://www.planetary.brown.edu/pdfs/4126.pdf">Full Paper</a></p>
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		<title>An Ordering of Convex Topological Relations</title>
		<link>http://umaine.edu/cis/2013/02/21/an-ordering-of-convex-topological-relations/</link>
		<comments>http://umaine.edu/cis/2013/02/21/an-ordering-of-convex-topological-relations/#comments</comments>
		<pubDate>Thu, 21 Feb 2013 17:01:38 +0000</pubDate>
		<dc:creator>megenhofer</dc:creator>
				<category><![CDATA[Recent Publications]]></category>

		<guid isPermaLink="false">http://umaine.edu/cis/?p=1625</guid>
		<description><![CDATA[M. Dube and M. Egenhofer, An Ordering of Convex Topological Relations, in: N.Xioa, M.P. Kwan, M. Goodchild, and S. Shekhar (eds.), Geographic Information Science &#8212; Seventh International Conference, GIScience 2012, Columbus, OH, Lecture Notes in Computer Science, Vol. 7478, Springer, pp. 72-86, September 2012. Abstract Topological relativity is a concept of interest in geographic information theory. One way [...]]]></description>
				<content:encoded><![CDATA[<p>M. Dube and M. Egenhofer, <a href="http://www.spatial.maine.edu/~max/convexOrdering.pdf">An Ordering of Convex Topological Relations</a>, in: N.Xioa, M.P. Kwan, M. Goodchild, and S. Shekhar (eds.), <em>Geographic Information Science &#8212; Seventh International Conference, GIScience 2012</em>, Columbus, OH, <em>Lecture Notes in Computer Science</em>, Vol. 7478, Springer, pp. 72-86, September 2012.</p>
<p>Abstract</p>
<p>Topological relativity is a concept of interest in geographic information theory. One way of assessing the importance of topology in spatial reasoning is to analyze commonplace terms from natural language relative to conceptual neighborhood graphs, the alignment structures of choice for topological relations. Sixteen English-language spatial prepositions for regionregion relations were analyzed for their corresponding topological relations, each of which was found to represent a <em>convex</em> subset within the conceptual neighborhood graph of the region-region relations, giving rise to the construction of the convex ordering of region-region relations. The resulting lattice of the convex subgraphs enables an algorithmic approach to explaining unknown prepositions.</p>
<p>&nbsp;</p>
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