Infrastructure Engineering - Research Publications

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    Observed spatial organization of soil moisture and its relation to terrain indices
    Western, AW ; Grayson, RB ; Blöschl, G ; Willgoose, GR ; McMahon, TA (AMER GEOPHYSICAL UNION, 1999-03)
    We analyze the degree of spatial organization of soil moisture and the ability of terrain attributes to predict that organization. By organization we mean systematic spatial variation or consistent spatial patterns. We use 13 observed spatial patterns of soil moisture, each based on over 500 point measurements, from the 10.5 ha Tarrawarra experimental catchment in Australia. The measured soil moisture patterns exhibit a high degree of organization during wet periods owing to surface and subsurface lateral redistribution of water. During dry periods there is little spatial organization. The shape of the distribution function of soil moisture changes seasonally and is influenced by the presence of spatial organization. Generally, it is quite different from the shape of the distribution functions of various topographic indices. A correlation analysis found that ln(a), where a is the specific upslope area, was the best univariate spatial predictor of soil moisture for wet conditions and that the potential radiation index was best during dry periods. Combinations of ln(a) or ln(a/tan(β)), where β is the surface slope, and the potential solar radiation index explain up to 61% of the spatial variation of soil moisture during wet periods and up to 22% during dry periods. These combinations explained the majority of the topographically organized component of the spatial variability of soil moisture a posteriori. A scale analysis indicated that indices that represent terrain convergence (such as ln(a) or ln(a/tan(β))) explain variability at all scales from 10 m up to the catchment scale and indices that represent the aspect of different hillslopes (such as the potential solar radiation index) explain variability at scales from 80 m to the catchment scale. The implications of these results are discussed in terms of the organizing processes and in terms of the use of terrain attributes in hydrologic modeling and scale studies. A major limitation on the predictive power of terrain indices is the degree of spatial organization present in the soil moisture pattern at the time for which the prediction is made.
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    Groundwater Quality Hydrogeological Assessments
    Lane, Mr Anthony ; Leonard, Mr John ; Weaver, Dr Tamie R ( 1999)
    Groundwater is a vital resource in Victoria. The Environment Protection Authority (EPA) and other authorities recognise the need to protect the quality of groundwater as a resource and as part of the natural environment. Hydrogeological Assessments (HAs) is one of the tools used to provide the information necessary to determine the status of groundwater quality or the effects of a proposal on the beneficial uses of groundwater. For example, a proponent of a new landfill or industrial development with potential to impact groundwater is likely to be required to perform a HA. The HA guidelines that have been published by EPA (EPA publication 668) provide an overview of HA methodologies, and the reasons for using different investigative techniques. The document presented here is a background document. It was commissioned and funded by the EPA; however it was never published by EPA. Instead, this document formed the basis for development of the guidelines, Hydrogeological Assessments (Groundwater Quality) Guidelines, published by EPA in August 2006.
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    Spatial data infrastructure concepts
    PHILLIPS, ANDREW ; WILLIAMSON, IAN ; Ezigbalike, Chukwudozie ( 1999)
    Several new concepts have recently been introduced in the areas of information management in general, and spatial data handling in particular. Concepts such as data warehouses, data marts, clearinghouses, data mining, interoperability, and spatial data infrastructures (SDIs) have emerged as potentially powerful tools to handle our spatial data. Some of these concepts are so closely-related that there are bound to be some confusion regarding differences between them, along with their potential applications. The purpose of this paper is to describe the concepts of data warehouses, data marts, clearinghouses, data mining, interoperability, and SDIs. The paper also explains the similarities and relationships between these concepts, where similarities or relationships exist.
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    Understanding the evolution of land administration systems in some common law countries
    TING, LISA ; Williamson, Ian P. ; Grant, D. ; Parker, J. R. (Commonwealth Association of Surveying and Land Economy (CASLE), 1999)
    This paper will outline the evolution of western concept s of land and property, from the tribal period through feudalism, the industrial revolution, capitalism/socialism and the current Kenyesianism/Privatisation phase which leads into globalisation and other trends. Examples will be given of the interrelationship between socio-economic changes, the dynamics of the humankind to land relationship and the legal/administrative infrastructure. Such an understanding is considered essential as a basis for cadastral reform. The paper identifies some lessons on the development of land administration systems: 1. The relationship between humankind and land will always be dynamic and changes at different rates across countries and regions as a result of varying economic, social and environmental pressures. 2. The direction which that dynamism takes is dependent on the society’s priorities. The current western trend towards tempering economic imperatives and planning decisions with more community-based concerns such as the environment and native title, is likely to lead to a new direction for land administration. 3. Appropriate legal and administrative infrastructures are crucial to the process of delivering the changes demanded by society. These infrastructures include the social, legal, economic and political processes. 4. The extent to which a society can successfully achieve its objectives depends in part on the tools available to achieve those aims. “We have the technology” does not mean anything until our society determines its preferred relationship with land into the future.
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    Cadastral trends: a synthesis
    TING, LISA ; Williamson, Ian P. ( 1999)
    An understanding of the human history behind cadastral systems is essential to understanding the dynamism of the humankind to land relationship and how this has driven and will drive cadastral reforms. The cadastral concept has developed significantly over the past few decades. During this time these systems, whether developed from a land market or land taxation perspective, have increasingly played a multi-purpose role. Since the time humankind learned to settle on land, cadastres have developed and evolved to suit society’s needs. Changes in the relationship of humankind to land have invoked matching evolutionary changes in the function of cadastres. The most recent examples are current world concerns of environmental management, sustainable development and social justice. Due to this, multi-purpose role cadastres are increasingly seen as fundamental to economic development, environmental management and social stability in both the developed and developing worlds. This paper reviews the trends in the humankind/land relationship and how these have affected the development and applications of cadastres.
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    Australian cadastres: the role of adverse possession of part parcels
    Park, M. M. ; Williamson, I. P. ( 1999)
    A comprehensive land information management system should ideally disclose the complete legal status of all land with disclosure of all public and private rights and restrictions, including rights acquired under adverse possession. Recognizing trends to develop national spatial data sets, if a national cadastre is ever to be considered, a basic requirement will be a unified national law regarding land ownership. In turn this will require a unified approach to the issue of adverse possession of registered title land and particularly adverse possession of part of a land parcel, which is, in the authors' view, a major obstacle in achieving this vision. With this in mind a review is given of current Australian (particularly Victorian and NSW) schemes regarding adverse possession of part of a registered title land parcel to indicate those fundamental differences requiring possible resolution.
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    A model of the decision process for GIS adoption and diffusion in a government environment
    Chan, Tai On ; Williamson, Ian P. ( 1999)
    The way a government organization conducts its business can be viewed as a public management system, consisting of a “public production process” in an organizational setting. In this system, many factors interact with one another to make it operate. Accordingly, the decision for the adoption and diffusion of GIS in such a system also will be subject to the influence of these factors. Based on the experience of GIS adoption and utilization observed in several Australian State government agencies in1995 and 1997, six such factors are identified, namely, GIS aligned dominant vision of decision makers, production infrastructure, production process, product mix, organizational setting, and the external environment of the stakeholders. Their relationships are described in a model which confirms the need for alignment between GIS and these factors in a government organization.
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    The different identities of GIS and GIS diffusion
    Chan, Tai O. ; Williamson, Ian P. ( 1999)
    GIS managers traditionally consider three perspectives of the nature of GIS when introducing GIS into an organization. When the GIS is developed to address focused and well defined problems of the organization, these perspectives adequately describe the changing identities of GIS in the study of its diffusion. However when the GIS is developed to address strategic, but vaguely defined problems, as typically is the case of a corporate GIS, these perspectives are inadequate for describing it. Therefore a new perspective is developed for the corporate GIS and the significance of the new perspective on GIS diffusion research is discussed.
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    GIS, the internet and the cadastre-coming together
    Polley, Lestyn ; WILLIAMSON, IAN ( 1999)
    This paper discusses the direction that the GIS, Cadastral and Internet industries have been moving in recent times. It proposes that while they are disciplines in their own rights, the move to providing widely useable information tools has seen them move closer together. As a result, GIS are becoming simpler information systems, the cadastral dataset is becoming a key portion of data within these information systems, and the World Wide Web is presenting these information systems to new user bases. It discusses how the gradual merging of these technologies is providing us with a tool which will be important in many
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    Facilitating digital spatial data transactions using an online tool
    Polley, L. ; Williamson, I. P. ( 1999)
    This paper presents an online system that facilitates digital spatial data transactions.The methodology used was to case study the requirements of one typical spatial datasystem, to determine its digital handling needs, and to implement and study a solutionto these needs. The case study is used to demonstrate that efficient digital datahandling methods are needed, and that these needs can be addressed throughappropriate use of technology such as the Internet and the World Wide Web.The use of Internet for digital spatial data dissemination and integration purposes isdescribed, along with the implications for the types of user of this spatial information.There is particular reference to using two-way flows of data to allow data custodiansto receive digital data as well as to disseminate it. The prototype was constructed withthese requirements in mind, illustrating the accommodated spatial processes andimplementation considerations. The paper assesses both the presented concepts andthe implementation itself.