Temporal GIS

The overall objective of this research project is to enrich geographic data with temporal and semantic components in order to significantly improve spatio-temporal analysis of geographic phenomena. To achieve this goal, we intend to establish and incorporate three new layers (structures) into the core of the Geographic Information by using mark-up languages as well as defining a set of methods and tools for enriching the system to make it able to retrieve and exploit such layers (semantic-temporal, geosemantic, and incremental spatio-temporal). Besides these layers, we also propose a set of models (temporal and spatial) and two semantic engines that make the most of the enriched geographic data. The roots of the project and its definition have been previously presented in Siabato & Manso-Callejo 2011. In this new position paper, we extend such work by delineating clearly the methodology and the foundations on which we will base to define the main components of this research: the spatial model, the temporal model, the semantic layers, and the semantic engines. By putting together the former paper and this new work we try to present a comprehensive description of the whole process, from pinpointing the basic problem to describing and assessing the solution. In this new article we just mention the methods and the background to describe how we intend to define the components and integrate them into the GI.

In California, the Vegetation Type Map (VTM) project of the 1930’s has provided valuable historical vegetation data. Albert Wieslander led this effort to survey the forests of California in the 1930’s. His crews surveyed over 150,000 km2, drawing detailed vegetation maps, taking 3000 photos and 17,000 vegetation plots. We developed a technique to digitize the Placerville 309quadrangle VTM, rendering it to a Geographic Information System (GIS). The map covers 2408.8 km2 of the west slope of the Sierra Nevada. In this area VTM crews identified 59 dominant plant species and eight genera or land cover classes and mapped their distribution into 3422 polygons. They identified recently disturbed areas that covered 13.5%of the landscape. We compared the digital VTM quad to CALVEG, a satellite-derived vegetation map from 1996. Land cover change for California Wildlife Habitat Relationship (WHR) vegetation types had occurred on 42.1%of the area. WHR types with the largest gains were: Montane Hardwood, Douglas-Fir, and Annual Grassland. Low elevation hardwoods, particularly Blue Oak Woodland (dominated by Quercus douglasii, Fagaceae), chaparrals and upper elevation conifers were the types that lost the most area. Differences in mapping techniques are unlikely to be the cause of this change because the analysis used controlled for map-based errors.  Potential causes of the observed change at these physiognomic levels of classification include human perturbation, succession, and climate change.

Archaeology is fundamentally concerned with both space and time: dates, chronologies, stratigraphy, plans and maps
are all routinely used by archaeologists in their work. To aid in their analysis of this material, the use of Geographic
Information Systems (GIS) by archaeologists has become widespread. However, GIS are conventionally ignorant of
time. Thus, if archaeologists are to achieve the fullest potential in the application of GIS to their studies, GIS are
needed that properly take into account time as well as space.
A GIS capable of dealing with temporal data is referred to as a temporal-GIS (TGIS), and commercial TGIS systems
currently exist. However, these are locked into a model of modern clock time. Archaeological time does not sit well
within that model, being altogether fuzzier and less precise. Nor are commercial TGIS able to address the questions
that archaeologists ask of their spatio-temporal data. Thus, a TGIS is needed that deals with the types of time that we
encounter as archaeologists, lest we end up shaping our data and questions to the inherent capabilities of nonarchaeological
TGIS.
The creation of that new TGIS is the subject of this book: a fuzzy TGIS built specifically for the study of archaeological
data that also takes into account recent developments in the theory of temporality within the discipline. The new TGIS
needs to be flexible and powerful, yet to ensure that it is actually used it must remain within the software horizons of
GIS-literate archaeologists.
The new TGIS has been applied to two case studies, one in prehistoric Derbyshire and one in Roman Northamptonshire,
producing informative and interesting new results. It is hoped that others will fruitfully use the

Groundwater quality is gradually deteriorating due to agricultural activities and its evaluation is there for eneeded before use. The aim of this study was to evaluate groundwater quality for use in the foundry industry using water quality data, including PH, EC, TDS, Cl and HCO3, from 26 wells located in Jolgeh and Bon-Rud districts, Iran. Zoning and classification of the area were done, based on groundwater quality, using a GIS software and the existing standards for water use. Results showed that groundwater in the East, North and Southwest of the area was of acceptable quality for use in the foundry industry, but water quality deteriorated from the East to the West of the area. It was found that for foundry industry about 4 percent of area ground water could be used without any limitation, 2 percent with low limitation, 7 percent with moderate limitations, and the rest with high limitation or even unusable. Agricultural activities in the region are having a negative impact on the quality of groundwater.

" Historians and Human Geographers deal with human systems or subsystems of considerable complexity. This situation presents a dilemma to those who use computational technologies, which demand a high level of precision to organize, analyze, and visualize information: the more complex the system is, the greater the imprecision of the available data. Historians and geographers often feel that their imprecise, ambiguous, contradictory, messy, largely qualitative information does not “fit” well in the available software categories, and they have trouble discussing the results produced when they work within computational environments because category assignment seems so arbitrary. This dilemma appears dramatically with the use of Geographically-Integrated History (GIH) as a research strategy. In this paper, we introduce fuzzy set theory (or fuzzy logic) as a proven solution for dealing with imprecision in complex systems.
"

"Most of the datasets presented in this thesis are available for free in ArcGIS shapefile format on the University of Edinburgh's DataShare Open data repository at http://datashare.is.ed.ac.uk/. These datasets are available for everyone to use as it is important to encourage data sharing in support of research activities. There are also some CORONA satellite images available on DataShare for the Syrian Jazira region.

I need to note as well that the archaeological dataset (http://dx.doi.org/10.7488/ds/1735) associated with this thesis has copyright protection, and my thesis must be cited in any publication that has incorporated this dataset into any research associated with it.

Relevant to CORONA, and the thesis, is a paper presented at a 1997 conference which first introduced CORONA satellite imagery to archaeologists doing research in the Near East.  Martin Fowler also wrote about the potential of CORONA in the Aerial Archaeology Research Group (AARG) news.

Mathys, Tony. “The Use of Declassified Intelligence Satellite Photographs in a GIS (IDRISI) to Map Archaeological Sites and the Surrounding Landscape in the Northeastern Region of the Syrian Jazirah. The University of Chicago Oriental Institute, NASA and St. Cloud State University Remote Sensing Applications in Archaeology Conference. St. Cloud, Minnesota, May 29-31, 1997.

Unfortunately, the Oriental Institute did not publish the papers presented at this conference; several academics, in attendance, built their careers on this presentation without any citation to it.

My gratitude and thanks to Dr Sarah Parcak for citing this unpublished conference paper in her book (Satellite Remote Sensing in Archaeology), and to Dr Aled Rowlands and Dr Apostolos Sarris for citing it in their Journal of Archaeological Science article 34 (2007)."

This thesis is copyright protected.
© 2001 Antone J.  Mathys. All Rights Reserved.""

The history of any place is shaped by the way that it is connected to other places across geographic space and by the way that these connections change over time. This chapter presents an innovative way --based on the ideas of Ernst Cassirer (1874-1945)-- to understand these complicated space-time issues.

Many applications such as planning, scheduling and natural language processing involve managing both symbolic and numeric aspect of time. We have developed a temporal model, TemPro, based on the interval algebra, to express such applications in terms of qualitative and quantitative temporal constraints. TemPro extends the interval algebra relations of Allen to handle numeric information. To solve a temporal constraint problem represented by TemPro, we have developed a method using constraint propagation, at the numeric and symbolic levels. In order to deal with real time applications or those applications where a complete solution cannot be obtained, we have modified the propagation techniques so that they will be able to solve temporal problems by giving a solution with a quality depending on the time allocated for computation.

Representing and reasoning about time is fundamental in many applications of Artificial Intelligence as well as of other disciplines in computer science, such as scheduling, planning, computational linguistics, database design and molecular biology. The development of a domain-independent temporal reasoning system is then practically important. An important issue when designing such systems is the efficient handling of qualitative and metric time information. We have developed a temporal model, TemPro, based on the Allen interval algebra, to express and manage such information in terms of qualitative and quantitative temporal constraints. TemPro translates an application involving temporal information into a Constraint Satisfaction Problem (CSP). Constraint satisfaction techniques are then used to manage the different time information by solving the CSP. In order for the system to deal with real time applications or those applications where it is impossible or impractical to solve these problems completely, we have studied different methods capable of trading search time for solution quality when solving the temporal CSP. These methods are exact and approximation algorithms based respectively on constraint satisfaction techniques and local search. Experimental tests were performed on randomly generated temporal constraint problems as well as on scheduling problems in order to compare and evaluate the performance of the different methods we propose. The results demonstrate the efficiency of the MCRW approximation method to deal with under constrained and middle constrained problems while Tabu Search and SDRW are the methods of choice for over constrained problems.

Path consistency is an important component of the resolution method needed to check for the consistency of an Allen’s Interval-based temporal network. While this local consistency algorithm reduces, in general, the size of the search space before applying the backtrack search, it implies the consistency of the problem for some specific temporal networks. Our goal in this paper is to maintain the path consistency of a temporal network in a dynamic environment i.e anytime a temporal relation is added or removed. For this purpose we propose a dynamic path consistency algorithm based on van Beek’s path consistency technique. Experimental tests on randomly generated dynamic interval-based temporal networks demonstrate the efficiency of our algorithm to deal with large size temporal problems in a dynamic environement.

This paper addresses urban block densification in a simulation context. The simulation of such a process requires several spatial analysis tools and specific knowledge on the types of objects accounting for the increased urban density. In this paper, only buildings creation is considered. The method proposed hereby takes into account the existing spatial organisation of an urban block in order to respect it while creating new buildings.

Comprendre les dynamiques urbaines est un defi d'une importance croissante qui peut etre traite de facons differentes. Pendant ces dernieres annees, une litterature importante a couvert le sujet dans des domaines de recherche tels que la geographie urbaine et economique, la geomatique. Neanmoins, quel que soit le domaine de recherche, afin de mieux comprendre les dynamiques urbaines, les changements effectifs subis par les objets geographiques au cours du temps doivent etre etudies. La conduite d'une telle etude necessite la constitution de bases de donnees spatio-temporelles contenant des donnees pour chaque etape des evolutions etudiees. La construction de ces bases de donnees est malheureusement un processus difficile qui requiert le suivi des objets geographiques dans les bases de donnees consecutives par la creation de liens. Les evolutions des objets topographiques suivis peuvent etre etudiees et ensuite simulees. Chaque objet est appele agent. Les simulations effectue...

This report introduces TimeBliography, a dynamic and online bibliography on temporal GIS. We provide a brief description of the bibliography as well as the components and functionalities of the web application that supports it. The bibliography is fully accessible on the Web at http://spaceandtime.wsiabato.info.

A well known approach to managing the numeric and the symbolic aspects of time is to view them as Constraint Satisfaction Problems (CSPs). Our aim is to extend the temporal CSP formalism in order to include activity constraints and composite variables. Indeed, in many real life applications the set of variables involved by the temporal constraint problem to solve is not known in advance. More precisely, while some temporal variables (called events) are available in the initial problem, others are added dynamically to the problem during the resolution process via activity constraints and composite variables. Activity constraints allow some variables to be activated (added to the problem) when activity conditions are true. Composite variables are defined on finite domains of events. We propose in this paper two methods based respectively on constraint propagation and stochastic local search (SLS) for solving temporal constraint problems with activity constraints and composite variables. We call these problems Conditional and Composite Temporal Constraint Satisfaction Problems (CCTCSPs). Experimental study we conducted on randomly generated CCTCSPs demonstrates the efficiency of our exact method based on constraint propagation in the case of middle constrained and over constrained problems while the SLS based method is the technique of choice for under constrained problems and also in case we want to trade search time for the quality of the solution returned (number of solved constraints).

A new data structure for the implementation of temporal
geographic information systems is presented. This data
structure, based on Kantabutra’s ILE database management
system, treats both time and place as first-class citizens
and utilizes direct linkages among entities that are related
to each other. The suggested data structure supports
naturally the three types of queries suggested by Peuquet
as queries that a temporal GIS database should be able to
answer.

This article introduces a type of DBMS called the Intentionally-Linked Entities (ILE) DBMS for use as the basis for temporal and historical Geographical Information Systems. ILE represents each entity in a database only once, thereby mostly eliminating redundancy and ...

Many applications such as planning, scheduling, computational linguistics and computational models for molecular biology involve systems capable of managing qualitative and metric time information. An important issue in designing such systems is the efficient handling of temporal information in an evolutive environment. In a previous work, we have developed a temporal model, TemPro, based on the interval algebra, to express such information in terms of qualitative and quantitative temporal constraints. In order to find a good policy for solving time constraints in a dynamic environment, we present in this paper, a study of dynamic arc-consistency algorithms in the case of temporal constraints. We show that, an adaptation of the new AC-3 algorithm presents promising results comparing to the other dynamic arc-consistency algorithms. Indeed, while keeping an optimal worst-case time complexity, this algorithm has a better space complexity than the other methods.

Many applications such as planning, scheduling, computational linguistics and computational models for molecular biology involve systems capable of managing qualitative and metric time information. An important issue in designing such systems is the efficient handling of temporal information in an evolutive environment. In a previous work, we have developed a temporal model, TemPro, based on the interval algebra, to express such information in terms of qualitative and quantitative temporal constraints. In order to find a good policy for solving time constraints in a dynamic environment, we present in this paper, a study of dynamic arc-consistency algorithms in the case of temporal constraints. We show that, an adaptation of the new AC-3 algorithm presents promising results comparing to the other dynamic arc-consistency algorithms. Indeed, while keeping an optimal worst-case time complexity, this algorithm has a better space complexity than the other methods.

Many temporal applications like planning and scheduling can be viewed as special cases of numeric and symbolic temporal constraint satisfaction problem. We have developed a temporal model, TemPro, based on the interval algebra, to express such applications in terms of qualitative and quantitative temporal constraints. TemProextends the interval algebra relations of Allen to handle numericinformation. To solve a constraint satisfaction problem, different approaches have been developed. These approaches generally use constraint propagation to simplify the original problem, and backtracking to directly search for possible solutions. Constraint propagation can also be used during backtracking to improve the performance of the search. The objectiveof this paper is to assess different policies for checking if aTemPro network is consistent. The main question we want to answer is how much constraint propagation is useful forfinding a single solution for a TemPro constraint graph. For this p...

This article introduces a type of DBMS called the Intentionally-Linked Entities (ILE) DBMS for use as the basis for temporal and historical Geographical Information Systems. ILE represents each entity in a database only once, thereby mostly eliminating redundancy and fragmentation, two major problems in Relational and other database systems. These advantages of ILE are realized by using relationship objects and pointers to implement all of the relationships among data entities in a native fashion using dynamically-allocated linked data structures. ILE can be considered to be a modern and extended implementation of the E/R data model. ILE also facilitates storage of things that are more faithful to the historical records, such as gazetteer entries of places with imprecisely known or unknown locations. This is difficult in Relational database systems but is a routine task using ILE because ILE is implemented using modern memory allocation techniques. We use the China Historical GIS (CHGIS) and other databases to illustrate the advantages of ILE. This is accomplished by modeling these databases in ILE and comparing them to the existing Relational implementations.

A key component of Al Gore's vision for a "Digital Earth" was the ability to explore a reconstructed past at all timescales. Many academic disciplines, such as history, archaeology and geology, share the problem of depicting continuous geographic change through time and correlating different spatio- temporal phenomena. A digital earth system with such visualisation capabilities would facilitate communication among experts, act as a tool for education, and enable complex information to be displayed to the general public.
The Temporal Earth project aims to combine Digital Earth's universality with the flexible expressivity of animated graphics. An initial prototype, named Sahul Time, presents a satellite-style depiction of ancient Australasia, with coastlines changing continuously as sea levels vary throughout the Ice Age. On further layers, time-dependent icons represent habitation periods for archaeological sites, and place-names change as land masses coalesce. The 'geotagged photo' concept has been extended to become a time-dependent view of a given scene. The timeline can be zoomed in to cover the historical timescale (200 years), or zoomed out to the geological timescale (200 million years). After the age of dinosaurs, fossils are transported vast distances upon tectonic plates until unearthed by palaeontologists.
The proofs-of-concept demonstrated in the visualisation prototype are now being translated into an extended KML schema, and toolkits will be released allowing discipline experts to author their own geo-temporal representations. Ultimately, Temporal Earth will provide an online digital earth system through which a user can explore space and time intimately, the interface selecting appropriate resources from its database according to space/time extents and granularity.

This is not a paper, but a spreadsheet showing alleged situation in the provincial, time-series part of CHGIS v4. database where the provincial capitals do not lie within the polygonal boundaries.  I have not had time to verify all these entries completely, and that is necessary.  However, what I know for sure is that there are lots of these errors, even if the exact number of 124 might not be correct. I will update this as soon as I finish the verification process.

Preferences in temporal problems are common but significant in many real world applications. In this paper, we extend our temporal reasoning framework, managing numeric and symbolic information, in order to handle preferences. Unlike the existing models managing single temporal preferences, ours supports four types of preferences, namely: numeric and symbolic temporal preferences, composite preferences and conditional preferences. This offers more expressive power in representing a wide variety of temporal constraint problems. The preferences are considered here as a set of soft constraints using a c-semiring structure with combination and projection operators. Solving temporal constraint problems with preferences consists in finding a solution satisfying all the temporal constraints while optimizing the preference values. This is handled by a variant of the branch and bound algorithm, we propose in this paper, and where constraint propagation is used to improve the time efficiency. Experimental tests, we conducted on randomly generated temporal constraint problems with preferences, favor a variant of MAC as the constraint propagation strategy that should be used within the branch and bound algorithm.

Simulation of complex Lotos specifications is not always efficient due to the space explosion problem of their corresponding transition systems. To overcome this difficulty in practice, we present in this paper a novel approach which integrates constraint propagation techniques into the Lotos specifications. These solving techniques are used to reduce the size of the search space before and during the search for a solution to a given combinatorial problem under constraints. In order to do that, we first tackle the challenging task of describing combinatorial problems in Lotos using the Constraint Satisfaction Problem (CSP) framework. In this regard, we provide two generic Lotos templates for describing CSPs and temporal CSPs (CSPs involving temporal constraints). To evaluate the time performance of the framework we propose, we have conducted several experimental tests on instances of the N-Queens, the machine scheduling and randomly generated CSPs. The results of these experiments are promising and demonstrate the efficiency of Lotos simulation when CSP techniques are integrated.