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Month: July 2017

Investigative Psychology

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ABSTRACT

In the last decade, structural properties of several naturally arising networks (the Internet, social networks, the web graph, etc.) have been studied intensively with a view to understanding their evolution. In recent empirical work, Leskovec, Kleinberg, and Faloutsos identify two new and surprising properties of the evolution of many real-world networks: densification (the ratio of edges to vertices grows over time), and shrinking diameter (the diameter reduces over time to a constant). These properties run counter to conventional wisdom, and are certainly inconsistent with graph models prior to their work. In this paper, we present the first model that provides a simple, realistic, and mathematically tractable generative model that intrinsically explains all the well-known properties of the social networks, as well as densification and shrinking diameter. Our model is based on ideas studied empirically in the social sciences, primarily on the groundbreaking work of Breiger (1973) on bipartite models of social networks that capture the affiliation of agents to societies....

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Stratigraphic Concepts

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Abstract

The sequence as an unconformity-bounded stratal unit was proposed by Sloss in 1948 (Sloss et al., 1949;Sloss, 1950, 1963). Sloss (1963) pointed out, "The sequence concept is not new and was already old when it was enunciated by the writer and his colleagues in1948. The concept and practice is as old as organized stratigraphy." Nonetheless, Sloss deservedly is given credit for developing the unconformity-bounded sequence as a stratigraphic tool. Sloss (1963) recognized six packages of strata bounded by interregional unconformities on the North American craton between latest Precambrian and Holocene deposits. He called these stratal packages "sequences" and gave them native American names to emphasize their North American derivation (Sloss, 1988). Sloss (1988) used these cratonic sequences as operational units for practical tasks such as facies mapping, although he felt that these sequences" have no necessary applications to the rock stratigraphy and time stratigraphy of extra cratonic or extracontinental areas" (Sloss, 1963). Although the concept of the cratonic sequence provided the foundation for sequence stratigraphy,

Additional Resource: Previous Stratigraphic Concepts and Terminology

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Selective Biodegradation In Hair Shafts Derived From Archaeological, Forensic And Experimental Contexts

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Summary

Background Hair is degraded by the action of both dermatophytic and nondermatophytic microorganisms. The importance of understanding hair sample condition in archaeological and forensic investigation highlights the need for a detailed knowledge of the sequence of degradation in samples that have been either buried or left exposed at the ground surface.
Objectives To investigate the sequence of biodegradative change to human terminal scalp hair from archaeological and forensic contexts.
Methods Cut modern scalp hair from three individuals with caucasoid-type hair was inoculated with soil microorganisms through soil burial in the field and under laboratory conditions to produce experimentally degraded samples. The degraded hair fibres were subjected to detailed histological examination using a combination of high-resolution light microscopy, transmission electron microscopy and scanning electron microscopy to investigate the nature and sequence of degradative change to hair structural components
Results ⁄discussion Degradation was found to occur first within the least structurally robust components that afford the least resistance to microbial ⁄chemical attack. The sequence of degradation

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Revisiting the Spatial Analysis of Crime in National Forests

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We examined spatial patterns of crime incidents in national forests covering 112,396 km in the northwestern United States. In this study we analyzed a database containing 40,003 spatially referenced crime incidents representing felonies, infractions, and misdemeanors during 2 calendar years (2003–2004) at several geographic scales. We applied several geospatial analytical techniques including quadrat analysis, nearest neighbor analysis (NNA), and nearest neighbor hierarchical (NNH) clustering to investigate crime incident spatial patterning. These geospatial tools were beneficial in identifying crime incident relationships contained within a large, complex spatial database. NNH clustering identified 15 regional clusters with 16,138 crime incidents, focused in the central portion of Oregon’s national forests, specifically in the Deschutes, Mount Hood, and Willamette National Forests. Subsequent NNA tests confirmed spatial patterning in all three forests. Closer examination of a confirmed hot spot in one forest revealed a recreation corridor with adjacent recreation destination amenities and a large proximate metropolitan area, a combination of circumstances not apparent at the initial regional analysis scale. Other spatial...

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Principles Of Stratigraphy

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Stratigraphy is That branch of geology that deals with formation, composition, sequence, and correlation of stratified rocks. Since the whole Earth is stratified, at least in a broad sense, bodies of all the different types of rocks—igneous, sedimentary, metamorphic—are subject to stratigraphic study and analysis. In most cases however, stratigraphy focuses on the evaluation of sedimentary rock strata. Modern principles of stratigraphic analysis were worked out in the 18th and 19th centuries by geologists such as Niels Stensen, James Hutton, Georges Cuvier, William Smith and Charles Lyell. By 1900 all the intellectual tools needed to establish the description, sequence, and correlation of strata were in place. Shortly after 1900, the tools needed to establish the absolute age of minerals containing unstable radioisotopes also became available, giving stratigraphers a physical basis for making chronostratigraphic correlations, at least in certain, favourable stratigraphic situations. Since the 1950’s effort has also been expended in establishing international standards for stratigraphic nomenclature, usage of stratigraphic terms, and the internationally agreed...

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Open Source/Non-Commercial GIS Products

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I’m a big fan of open source software, including geospatial software, such as QGIS and GeoServer, and it’s not just because it can be used without paying a license fee. The best thing about open source is the community of users that share their code and support one another through shared applications, documentation, tips, and tricks. This is the same spirit that exists in the Pitney Bowes user community (Li360), ESRI’s GeoNET, and the countless other software communities of practice.

The question is, which GIS software is the best choice for an organization?

If you ask commercial vendors, they’ll explain that their paid-for solutions offer a higher level of reliability and quality. However, most QGIS users and consultants will say that their solutions are free, making them more attractive to the cash-strapped user. In fact, some QGIS users talk about open source software as if it’s air — a gift to the GIS community from selfless developers committed to the greater good. Let’s consider this more closely.

Additional Resource: Open Source or Commercial GIS, or both?

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On-Site GIS Digital Archaeology

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The 1990s witnessed the progressive ‘miniaturization’ of personal computers and other digital devices. This affected virtually every type of business, research program, as well as the daily lives of millions of people around the world with access to electricity. The development of portable high-speed personal computers and other data collecting devices was not lost on archaeologists who have always had a deep interest in utilizing technological and scientific methods to advance their recording and study of the past (Renfrew and Bahn 2004). In 1997, when the University of California, San Diego initiated the deep-time study of ancient metallurgy and social evolution in Jabal Hamrat Fidan (JHF) region of the Faynan district in southern Jordan, a fairly traditional style of ‘analogue’ or paper archaeological recording was carried out during the first season of excavation. With the exception of using a very expensive Sony video camera for taking digital still photographs of...

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Interfaces: Mobile GIS in archaeological survey

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You are surveying a broad, featureless plain and the planned coverage area is delimited in a Geographic Information System (GIS), but how do you rapidly locate your starting position and line up your survey crew with few landmarks? Your Global Positioning System (GPS) will get you to the survey area, but figuring out the coordinates is time consuming. Ideally, local maps and imagery, the survey coverage area, and yesterday’s coverage are available on a screen with your current GPS position indicated. You have discovered a site consisting of lithic concentrations of different material types, and each looks like a distinctive reduction event, but you only have 45 minutes to record and collect at the site. Using common GPS methods, you can map each concentration as a polygon feature, assign an ID number to it, document and collect it, and attribute it later. Alternately, you open the “lithic locus” geometry in a mobile GIS and map in each concentration. The GIS assigns a new ID number to the locus,..

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Grids And Coordinates

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Latitude lines run east-west and are parallel to each other. If you go further north north, latitude values increase. Finally, latitude values (Y-values) range between -90 and +90 degrees

But longitude lines run north-south. They converge at the poles. And its X-coordinates are between -180 and +180 degrees.

Latitude and longitude coordinates make up our geographic coordinate system.

Map Coordinate Systems You can give anything on Earth latitude and longitude coordinates.

The field of study that measures the shape and size of the Earth is geodesy. Geodesists use coordinate reference systems such as WGS84, NAD27 and NAD83. In each coordinate system, geodists use mathematics to give each position on Earth a unique coordinate.

A geographic coordinate system defines two-dimensional coordinates based on the Earth’s surface. It has an angular unit of measure, prime meridian and datum (which contains the spheroid).

As shown in the image below, lines of longitude have X-coordinates between -180 and +180 degrees.

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Grid Services for E-Archaeology

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Abstract

Archaeological data collection is based on the description of archaeological contexts. An archaeological excavation demolishes the original matrix within which the cultural material is found and special care is taken to record spatial context. Each artifact is described in terms of its physical and spatial properties as well as its relation to the matrix (for example soil composition). As several thousands of artifacts can be unearthed during a field season, there is a need to develop digital resources and collections that focus on the publication and preservation of data and the creation of tools for the analysis of these data. The first section of this paper presents preliminary results and the lessons learnt on the development of a prototype for an Australian archaeological digital collection based on data grid middleware and infrastructure. The second section introduces a versatile 3D reconstruction tool that visualizes the excavated archaeological artifacts with its associated stratigraphy. The data come from two major archaeological projects in Queensland, Australia: the Mill Point Archaeological...

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