Number Of GIS Research Articles

The Locating Chromatic Number of Book Graph

Let G = V G , E G be a connected graph and c : V G ⟶ 1,2 , … , k be a proper k -coloring of G . Let Π be a partition of vertices of G induced by the coloring c . We define the color code c Π v of a vertex v ∈ V G as an ordered k -tuple that contains the distance between each partition to the vertex v . If distinct vertices have distinct color code, then c is called a locating k -coloring of G . The locating chromatic number of G is the smallest k such that G has a locating k -coloring. In this paper, we determine the locating chromatic number of book graph.

On Double Domination Numbers of Generalized Petersen Graphs

A (total) double dominating set in a graph G is a subset S ⊆ V(G) such that each vertex in V(G) is (total) dominated by at least 2 vertices in S. The (total) double domination number of G is the minimum size of a (total) double dominating set of G. We determine the total double domination numbers and give upper bounds for double domination numbers of generalized Petersen graphs. By applying an integer programming model for double domination numbers of a graph, we have determined some exact values of double domination numbers of these generalized Petersen graphs with small parameters. The result shows that the given upper bounds match these exact values.

Applications of a New Separator Theorem for String Graphs

An intersection graph of curves in the plane is called astring graph. Matoušek almost completely settled a conjecture of the authors by showing that every string graph withmedges admits a vertex separator of size$O(\sqrt{m}\log m)$. In the present note, this bound is combined with a result of the authors, according to which every dense string graph contains a large complete balanced bipartite graph. Three applications are given concerning string graphsGwithnvertices: (i) ifKt⊈Gfor somet, then the chromatic number ofGis at most (logn)O(logt); (ii) ifKt,t⊈G, thenGhas at mostt(logt)O(1)nedges,; and (iii) a lopsided Ramsey-type result, which shows that the Erdős–Hajnal conjecture almost holds for string graphs.

An Analysis of the Location of Burial Grounds in Västmanland, Sweden

This thesis presents a number of GIS based landscape analyses that together aim to explore aspects of the social development in Iron Age Vastmanland, central Sweden. From a perspective where nature and culture are seen as integrated in the landscape, differences in the relations to the physical landscape are interpreted as reflecting social organisation. Thus, hydrological modelling of watersheds is used for understanding the development of territories and regions that are recognisable in the outlay of the medieval hundare districts. Statistical modelling of burial grounds together with variables describing their situation in the landscape is used to calculate an estimated chronology for sites that have not yet been excavated. This information is used to analyse differences in how the setting in the landscape can tell of different trends in claims to land and property rights. An extensive renegotiation of property rights is suggested to have taken place after climatic catastrophe in AD 536 and the years after. This is interpreted as having caused a substantial population decline in parts of Scandinavia. The social development after this includes an increasingly stratified social hierarchy in the Late Iron Age, which is reflected in the construction of grave monuments. New GIS methods for analysing how to interpret the perception of different locations of the landscape, in terms of local topography and soil are discussed in relation to this. How to make the best use of large datasets of archaeological information in combination with other sources of geographical information is a central theme. Geographically Weighted Regression is used to predicting the representativity of the registry of graves for the whole landscape. It is suggested that the increasing availability of archaeological information in digital format, together with new analytical techniques has the potential to introduce fruitful new research perspectives. This will make it increasingly rewarding to work with the large amount of data produced from rescue archaeology, and it is important that this information is managed in a structured manner.

On the edge coloring of graph products

The edge chromatic number of G is the minimum number of colors required to color the edges of G in such a way that no two adjacent edges have the same color. We will determine a sufficient condition for a various graph products to be of class 1, namely, strong product, semistrong product, and special product.

A real-time hydrological model for flood prediction using GIS and the WWW

The purpose of this paper is to examine the current status of real time hydrological models used for flood nowcasting and hazard mitigation and indicate how WWW-based systems can overcome some of the limitations of existing systems. Whilst hydrologically innovative and robust models are available, they are poorly suited to real time application, are often not well integrated with spatial datasets such as GIS. Current systems also lack flexibility, customisability and accessibility by a range of end users. We describe the development of a Web-based hydrological modelling system that permits integrated handling of real-time rainfall data from a wireless monitoring network. A spatially distributed GIS-based model is integrated on the basis of this incoming data, approximating real-time to produce data on catchment hydrology and runoff. The data can be accessed from any WWW interface, and they can be analysed online using a number of GIS and numerical functions. We discuss the potential users of such a system and the requirements for interfacing model output with these users for hydrological nowcasting and spatial real-time, emergency decision support. Rather than discuss developments in the modelling of hydrology for flood hazard mitigation, this paper focuses on developments in interfacing these models with end users.