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Environment and Planning B: Planning and Design 2002, volume 29, pages 513 ^ 531

DOI:10.1068/b12818

Visualizing decisionmaking: perspectives on collaborative and participative approach to sustainable urban planning and management Habib M Alshuwaikhat, Danjuma I Nkwenti

Department of City & Regional Planning, College of Environmental Design, King Fahd University of Petroleum and Minerals, Dhahran, 31261 Saudi Arabia; e-mail: [email protected], [email protected] Received 13 May 2001; in revised form 30 August 2001

Abstract. Over the last two decades shifting human resources, socioeconomic potentials, and innovations in information technology and communication have all but overthrown the formal order of the planning and management of urban systems. The authors trace the causes to misplaced priorities in urban governance and related issues, via the interface of infrastructure systems and land use. They survey some major theoretical and applied decision-support systems collaborative planning systems, and collaborative decision-support systems which have been advanced to date, indicating their strengths and weaknesses with regard to their ability to anchor public participation and professional collaboration in key planning and management issues. They highlight the fact that, although relevant multivariate, disaggregated, and incoherent small-scale researches do yield high dividends, their lack of cohesive interrelationship is related to the fragmentation of urban systemsödespite various attempts at bringing about sustainable development. They suggest that decisionmaking can be effective when all aspects involved are visually related and collectively executed. They conclude by emphasizing that a comprehensive approach needs to be adopted for the planning and management of urban centers in order to enhance systems performance, human interaction, and contained developments.

Introduction For the last thousand years, exploitation of human and material resources has been the main driving force in the development of most cities. Yet not enough groundwork has been done to ensure continuity of the resources or to avert the spatial conflicts which are likely to result from the changing circumstances that surround most new technologies and stem from the vigor with which they are adopted. Blame for this has largely been attributed to the inadequacy of planning theories or the myopic attitude that oversaw their implementation. According to Needham (2000), ``When setting out what is claimed to be a coherent and fairly general theory of spatial planning, it is necessary to be explicit about three things: the activity to which the theory refers, the attitude taken towards that activity, and the attitude taken towards rationality'' (page 438). Elsewhere, he underlines two different motivations for theorizing about spatial planning. First, there is the objective approach to spatial planning, which stems from a wish to understand the social activity of spatial planning better, and second, there is the normative approach, which is designed to improve the practice of spatial planning. Further, spatial planning as a design discipline can be regarded as the activity of a public body when it takes responsibility for bringing about change or protecting the spatial disposition of activities, buildings, spaces, and related activities, as well as undeveloped land, from change. To transcend this mammoth task, various options have been advancedöchiefly in the form of planning decision support systems. One of the solutions advanced is that needs to shift from close associations with both economics and modernist tendencies and to consider the roles of sociocultural and political forces that shape cities (Sandercock, 1998). In a similar vein Batty (2000a),

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H M Alshuwaikhat, D I Nkwenti

calls for a unification of aggregate patterns of urban description with the idiosyncratic case studies of individual behavior in an urban setting. That issues of space and planning should figure so succinctly and unequivocally in the running of organizations and cities is no accident, nor is it a matter of choice. Space and its planning have become de facto in achieving and sustaining both political and financial power. This broad and somewhat general survey of the issues seems to beg the question of what is the necessary and sufficient condition for addressing spatial planning? A logical approach would be a close examination of the structure of urban systems, the various patterns of formation, as well as the principles that have governed them to date. However, there have been some difficulties in using simulations of landuse ^ transportation models in the analysis of urban systems. One of the reasons for this is that, even with the inclusion of exogenously determined variables, they remain more abstractions than tools of certainty in the representation of real-world systems and processes (Torrens, 2000). This translates into a shortcoming which can be attributed to the lack of effective medium, methodology, and, perhaps, intention. The proliferation of visual interfaces, particularly of three-dimensional data, which is available outside the profession might, somehow, bridge this gap. Methodology In this paper we provide a general literary survey. Instead of focusing on a single aspect, we attempt to cover the overall components which together constitute an urban setup. In the first part we look at the intricacies involved in approaching planning through the interfaces of infrastructure and of land use. In the second we raise the issue of sustainability and related decision-support systems. Thus our approach is not only grounded within research, but also extends to the wider public. In the third part we draw on the cases surveyed, and give a discursive conclusion including a viable approach to sustainable urban centers. Integrating urban infrastructure systems When considering the development of infrastructure systems of an urban center, three key issues should be borne in mind. The first is the provision of flexible means of commuting or transiting between residences, work, recreation, and other related locations. The second is the supply of power, water, and similar basic needs for the sustenance of the activities of an urban center. And the third is the frequency of removing waste generated as a result of human interaction. The ability to synchronize these aspects and translate them into a meaningful scheme resides with the planning and management structure. Yet the initiation and supply of such services have been the domain of various specialist engineering concerns. This has resulted in a conflict of interests regarding rights of way, the extent and depth or height of roadways, and the like. However, what is worth investigation is the variability of services provided, the categories of their benefactors, and their overall quality with respect to the integral nature of urban spatial systems. As a discipline, urban infrastructure has been successfully used as a powerful and dynamic avenue for the study of contemporary cities with regard to the increasing activity of class and cultural dynamism. Across many Western and North American cities the unfortunate nature of the `haves' and the `have nots' divide, and the increasing marginalization of the urban poor in developing countries, have resulted in a new spatial configuration wherein consumerism forcefully dictates the pace, the rules, the quality of space, and of its adjoining services. Recent studies reveal that although this is not a new phenomenon, its impact on the development of a city has repercussions on the planning and management of related resources. The key impetus is the privatization of most public infrastructure,

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as has been the trend in the United Kingdom and other European countries in the past few decades. This is related to most governments' inability to identify, regulate, and provide for their marginal populations, who are either temporal immigrants or welfare beneficiaries. The growing demand from some sectors of business and taxed employees for equal contributions to shared resources has further compounded the difficulties. Privatization has been resorted to as a possible way out of the current dilemma, though it far from solves the problem of spatial consistency or the obligation of catering for the poor and needy. The situation has metamorphosed into a complex sociopolitical and socioeconomic polarization, wherein a new class of entrepreneurship has taken over the mantle of regulating and marketing infrastructure commodities. The trend is more or less characterized by segregated and fragmented urban spaces, the creation of gated communities, and rapid links between them and the other more specialized spaces that have come to be known as foreign direct investment (FDI) outlets. Such links are routinely referred to as `glocal' (Graham, 2000). The influence of `glocalism' is manifest in many emerging developments, such as `Cybercity' in the United Arab Emirates, the multimedia gulch in the south of the Market area (SOMA) in San Francisco, Tokyo's teleport town, the Brooklyn MetroTech, digipots in the Caribbean, the Philippines, and India, as well as other newly developed business improvement districts (BIDs), such as those in central Manhattan. The issue at stake is that of the extent to which these developments impact on the planning and management of urban systems. A primary consideration is that of subtle interaction and geography. There is a measure of interaction within most quasi-independent communities (QICs) that is not readily comprehended at the level of planning organizations because these are sociotechnologically driven and, therefore, subject to various approaches of design/build/ operate/maintain (DBOM) schemes. The complexity of interaction, together with sociocultural backgrounds that are hardly discernible, make it even more difficult to generalize the operations of firms concerned with such developments. However, controlled access and pricing to delimit congestion and enhance efficiency is an issue that is becoming standard as these systems can be controlled by electronic identification and direct digital pricingöwith a corresponding digital payment. This e-transaction ensures that the firms and corporations involved can reduce both time and space and, at the same time, expect to achieve substantial returns on their investments within a very short time. This shift from supply-oriented infrastructure to demand-oriented infrastructure is the central theme of the `fortressed' enclave developments in the Brazilian coastal city of Sa¬o Paulo. The success of the scheme depends on connection with other enclaves, the provision of reliable water and electricity mains, high-capacity telecommunication and mobile communications for the sole use of the affluent. This image has been dented by heightened bias and unevenness, vis-a©-vis the masses. It is situations such as these that have reinforced the call for a more egalitarian-oriented infrastructure supply. Deregulation and privatization occur within zones or sub-urban areas such as the BIDs or FDIs, which are imbued with internationally oriented infrastructure networkers as opposed to infrastructure networks regulated by territorial government, which are often substandard or poorly managed. This leads to tensions which pose serious threats to urban concentration unless there is a counter offer in the way of some premium infrastructure network within the urban center. This has been observed in many Western, North American, and Eastern and Southeast Asian cities, wherein the recession of public infrastructure invariably leads to hegemonic forms of urban infrastructure development. At the same time the construction of network spaces, with upmarket street systems, power, water, transportation, and telecommunication in

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selected locations for an elite class has a direct effect on the development of the poor. The sociotechnical and politicoeconomic changes that are introduced by these network spaces give rise to changes in the status quo of urban systems. This is manifest in the unbundling of urban infrastructure or, more accurately, the money-enhanced development of infrastructure to the benefit of QICs, the collapse of comprehensive urban planning in favor of new consumption spaces, the emergence of infrastructure consumerism, and a shift towards automobilized cityscapes. As an example of a counter measure, the problem of parking in Hong Kong has forced the government into a restrictive approach to automobile-related planning within the city (Wong et al, 2000). One category of mobility that is increasingly being turned to is automated people mover (APM) systems. The features of APMs which make them attractive for adoption within urban centers include their variability, flexibility, and cost effectiveness with respect to layout, environmental sensitivity, commuting distance, and integration with other systems. The development of APMs may be a compromise solution to the challenge of restricting urban sprawl and, at the same time, clearing the urban center of motorcars and related systems. Earlier solutions of transit systems such as the metro links, light rails, and similar, have been unsuccessful in most countries or cities because of the absence of suitable headway, or regularity and consistency of service. APMs have no such shortcomings, and therefore provide a welcome change, though at present they are still restricted to the engineering domain. Although it can be argued that the services provided by APMs go a long way to reinforcing the emergence and establishment of QICs, BIDs, and FDIs, their application as a bridge or intermediary transit, both for mass and for selective class movement, can articulate a sense of place within an urban center. Recent technological innovations make it possible for the systems to be used on-grade with their right-of-way providing an avenue for greening the most depleted urban centers. The option of overhead support means they can also be used conveniently over most historic sites without the need for serious displacement or clearance as is the case with the automobile. Usually, they are developed to cater for a neighborhood of approximately 200 ^ 335 m2 (Warren and Kunczynski, 2000), with a population of about 5000. Such a community is deemed to be self-contained, and therefore not needing to commute beyond the neighborhood except in special circumstances. Generic types are either shuttle or loop, with a range of between 2 and 4 km, and use either monorails or dual tracks. These provide a convenient maximum necessary walking distance of 3 ^ 5 minutes within the neighborhoods that they serve. Therefore, one would imagine that they provide a complete solution to the problems of the urban poor? In practice this is far from the case. The provision of portable water, power, waste disposal, and, to an extent, telecommunication are more pressing needs for the poor than is the need to commute. In the face of privatization, the development of FDIs and BIDs, the poor find it almost impossible to compete for those resources that are crucial to their very survival. As a result, they tend to impede, or even impair the flourishing of both FDI and BID infrastructure. It is the responsibility of the respective governments to make adequate provisions for safeguarding such outcomes, by defining and enforcing appropriate service standards that cater to the particular needs of the poor (Cowen and Tynam, 1999). Privatization has resulted in the poor or urban underclass as being overshadowed by a wave of local monopoly that is more or less profit oriented. The result has been the removal of subsidies for vital supplies for those who cannot pay up front. Options available to governments include the adoption and implementation of new or emerging technologies such as cell phones, and condominial water and sewage systems. This can be enhanced by the use of smart-card payment techniques, and


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load limiters to regulate the consumption of electricity and water. Other means of getting around the issue of providing adequate infrastructure to the urban poor, yet holding down costs, have ranged from the provision of alternative technologies such as solar energy, the limitation of consumption of water for domestic use, and the recycling of waste. It has been found that in most cases, when there is community involvement or participation from the inception of a scheme through to its implementation, the success of the scheme makes the effort worthwhile. If these measures can be tied in with appropriate transportation and housing schemes, then the use of space and relevant services can be controlled. The controversy surrounding this last aspect, such as the dumping of toxic and related waste within the neighborhood of the marginalized populace, calls for extreme caution in planning and administering the supply of much-needed infrastructures at the expense of health risks which may result in epidemic outbreaks. This can be more expensive for any government or organization than the supply and regulation of appropriate infrastructure. On the other hand, the planning of waste-recycling plants within commuting distance of some neighborhoods may be a way of generating employment. This is an issue which can be debated only within the broader scope of land-use considerations. Assimilating land-use planning The concept of land use has been the subject of elaborate studies, evolutions, and innovations over the last two decades, since the advent of modeling in the 1960s. Yet the dynamism and cross-influences that it generates and receives have made it almost impossible to pin down a particular approach with regard to its planning and deployment. As a result, many scholars tend to look at land-use planning as an art, rather than as a science that can be explicitly relied upon for the provision of a solution to the numerous problems that confront urban planners and managers. Land-use planning is one component of an overall policy related to land development of governments and organizations charged with its responsibility. The planning and development of land use involve a complex set of interactions between market forces, governments, planners, and various interest groups (Kaiser et al, 1995). Although government is expected to set the rules of the `game', it must rely on expert knowledge from planners, who must meet as best they can the increasing demands of market forces generated by bankers, realtors, developers, and landowners. On the other side, advocacy groups such as environmentalists, minority groups, and farmers tend to oppose plans which are insensitive to their peculiar aspirations. This state of affairs has been responsible for the stalemate that has hindered the prescriptive approach to land-use planning for so long. Though the comprehensive rational approach, as it is sometimes called, provides a means of addressing problems in the short term, it has been seriously criticized for its inadequacy in handling long-term planning requirements. This is because of its strict adherence to exhaustive information collection and goal formulation at the onset, which is followed by even more demanding design, and evaluation of the consequences of alternative plans. This leaves the approach at the mercy of rapidly evolving information systems and a highly dynamic population, which are all the while being influenced by market forces. The main forces responsible for the shift in the approach to land-use planning are related to the change in information processing and the reassessment both of production and of consumption of resources. Prior to the information revolution of the late 20th century, land-use planning was centered on the need to separate conflicting functionsösuch as industrial and residential areas. Later, it was found that such separation did not auger well for the environment. For this reason, the move was

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initiated for compact planning, which sought to eliminate the need for commuting across the urban center on a daily basis. Because of certain social and related problems with compact planning, today, other variants of the two approaches are being tried out in many parts of the world. The realization that cultural dynamism has much to contribute to the equation of planning is weaving yet another game rule. At the same time, more scientific contributions are being sought to make the task of planning, and the complexity of spatial systems, more pliable, if not comprehensive and controllable. The study of urban systems from the perspective of spatial econometrics is perhaps not new to urban planning. However, the need for fresh insight into the causes of urban concentration, at the same time refuting the oversimplification of the deductive theories of recent trends in economic geography, make it a valid tool. The way a given urban center or region evolves results from different forms of contingent dynamics, its own inherent characteristics and those of the adjoining centers or regions (Fingleton, 2000). One such dynamic is planning control. Investigative studies on the influence of planning control decisions (Tang and Choy, 2000) as a tool in the generation of policy suggest that little is known of how this is actually carried out in most instances. Though it has to do with a complex deliberation process involving the consideration of many factors, some authorities make it a closed-door affair. This not only compromises both qualitative and quantitative information, but in addition impinges on the advantages which can be derived from the interaction between planning and market forces, between policy, decision, and their outcomes, as well as the rigidity and flexibility of the overall policy mechanism. As much as strong policies are required in planning control decisions, the need for local participation cannot be ignored at any period in the generation of those policies, even if it is limited to a selected class of informed groups. This approach, it is believed, can assist in balancing the relatively simple but nonproductive policies resulting from hierarchy and standards, as opposed to those relatively complex but productive policies resulting from a wide range of objectives and consensus (de Roo, 2000). Successful land-use planning emanating from sound policies has in addition been found to possess factors that distinguish between centrally located activities, with a concentration of certain specialized activities such as leisure on the one hand, and business on the other hand. Whereas businesses require highly trained manpower, faceto-face interactions with clients, and rapid access to their operations (Berkoz, 2000), leisure tends to favor locations which are not in the ordinary run of daily spheres. In some major cities with outmoded industrial neighborhoods, it has been found that the introduction of leisure-oriented activities can help rejuvenate otherwise abandoned structures, with highly viable results. The introduction of leisure in a purely commercial or business neighborhood, as part of night life, can assist in the reduction of crime rates, increase in the vibrancy of the town center, and can balance one-sided design considerations characteristic of the previous segmental planning approaches. Although the introduction of leisure into an urban center can have positive effects in large centers, caution should be exercised when dealing with small towns or provincial centers: this is regarded as one of the things that can seriously jeopardize the future of an urban center as a hub of the environment (Ravenscroft et al, 2000). As mentioned above, the advent of information technologies has brought about changes in the way businesses and households operate. This has a knock-on effect on the way spaces are planned and used, including their related activities. Although transportation may be the catalyst in the initiation of spatial interaction, it is much more useful to approach spatial interaction from the perspective of functional activities. Some of the defining parameters involve the resolution of location choice, based on localized spatial context, density constraints, and environmental constraints.


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Thus, both for households and for businesses, this is a composite outcome of the interaction of individual choices (Waddell, 2000), being related to an ability to surmount the various bid rents. To generalize spatial planning in the current atmosphere of technological innovation, increasing mobility, and the continuous flux of people, goods, and materials, two central ideas have emergedöwith some local variationsöacross many European cities. One is spatial concentration; and the other is spatial deconcentration. However, though these terms may sound antithetical, they actually form a complementary and acceptable approach to tackling the otherwise illusive situation that has characterized planning for so long. The two rely on reflexivity and heterotopias (Bertolini, 2000) for the grouping of activities requiring physical interaction, or making explicit provision for interconnectivity between functions and services that are remotely located. Apart from the examples of BIDs and FDIs examined above, other developments include accentuating station areas as a major hub for boosting peer-to-peer interactions, educational exchanges, and historic reenactments. These developments add impetus to the commuting experience, with resulting benefits for businesses and related services. On the other hand, the development of high-tech `proximity offices', as has happened in the Paris region, has been found to alleviate the problems of traffic congestion and, at the same time, those of social isolation common to people who have to drive long distances to work or those who work from home. Thus, application of the concept of APMs and BIDs to station areas and `proximity offices' can provide a better mix in the drive for enhanced spatial planning. When supporting infrastructure for these various developments is tailored to optimum performance, a satisfactory pattern can be derived for any comprehensive urban system. The only aspect that needs more elaboration is the virtual interaction that must take place between the proximity offices and other locations within the CBD or FDI hubs located in various countries around the world. The issues relevant to these remote interactions can be readily grasped by examining the complexity of the virtual environment. Planning for the virtual environment The activities of an urban center that are related to virtual environments are now being given attention by planners. It may be only a subset of overall human interaction, but its significance for any city or organization is so tremendous that it has been given priority in some cases. Corporate organizations have been the first to latch onto the global network, essentially for the sake of marketing. According to Dutta (2000), there are over 224 million Internet users in Europe and North America alone, responsible for over US $120 billion in on-line transactions. Their number is expected to be somewhere in the vicinity of 500 million by the year 2003, with transactions of US $1.3 trillion. What makes this so significant is the speed with which transactions are carried out, and the ability to custom design goods and view their final shape and specifications before placing an order. In addition, there is the range of choice and facility for price cross-referencing. These are common features in leading e-commerce sites such as Amazon, e-Bay, Sony, and others. This has provided the vendors with the ability to invert the value chain and make the consumer a starting point for major sales. By eliminating guesswork and treating the consumer as a special customer, the vendors ensure that they not only cater to individual needs but also establish a link for future sales. This is particularly important in the era of time-starved professionals, who often do not find time for enough sleep let alone to indulge in window-shopping. To plan for such ventures, and those reflective of other organizations, the Internet has been considered to require tight cross-functional integration of services, and all the

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personnel involved in related development and management. Apart from the fluid flow of information, highly specialized skills are required, as well as the necessary software and hardware. These last aspects have been characterized by a high degree of variability over the last three decades (Batty, 2000b). However, it is hoped that the introduction of Application Service Providers (ASPs), paving the way for Internet computing, will facilitate the task of storage and running most applications for ordinary users. However, specialized firms and organizations may still have a need for specific implementation as well as hosting their own databases. This is where expert knowledge will count. Computing applications at the level of major firms and organizations are a matter of specifics. Those related to the field of planning have some special characteristics, which require close attention in selection and implementation. There may never be a specific program of implementation that exactly meets the needs of all users within the planning environment, as some of them are large organizations with multiple users, whereas others are single users requiring, at most, a workstation. However, the basic implementation requirement will be that which is necessary to carry out satisfactorily any given project of the firm or organization. This implies the ability to establish a project, execute it, and subsequently transmit it over an intranet or Internet. Transmission of data over a network involves issues of security, speed, capacity, the nature or type of data, the intended users or receivers, the type of equipment in use for the operation, as well as the know-how of the operators. In a virtual environment involving the use of geographic information systems (GIS), global positioning systems (GPS), virtual reality three-dimensional representation (3D), computer simulation (SIM), and network connectivity (NT), the centerpiece is often a GIS platform that acts as a hub for the other systems (McKenzie, 1998) or processes that route their applications through it. Cross-spatial interactions The interactivity between real urban space and virtual urban space is of interest in the planning and successful management of urban systems. There are three main aspects confronting authorities, organizations, and planners across the world: the regulation of virtual-to-virtual interactions, virtual-to-real interactions, and of real-to-virtual interactions. The reason for this is that, unlike their real-world counterparts, except for some specific cases, it is almost impossible to monitor the millions of transactions that occur over the global network. In addition to this, web pages have the peculiar ability to mushroom almost overnight and disappear with similar alacrity. The situation in part results from the frequency with which most firms and organizations change their image to suit their growing status. On the other hand, some pages are simply orphaned by negligence or time pressure on the part of those responsible for their upkeep (Smith et al, 1998). Virtual-to-virtual interaction

This is perhaps the most elusive and most difficult space to regulate in terms of planning. However, some governments and organizations have made considerable efforts in policing the Internet, particularly with regard to immoral materials, creditcard theft, and outright vandalism. Nevertheless, the positive effects are enormous in terms of image projection and communicative appeals of one kind or the other. In this category, most web pages that require no more than ordinary browsers can be accessed directly from personal pages or home pages. Pages dealing with e-commerce or corporate bodies provide information in a combination of text and graphics for a wide variety of uses, such as background information, products offered, financial status, and job offers. The kind of interaction here is passive, in that the user is not engaged in any


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real-time exchange of information with the site. An advanced version of this type of interaction involves the use of personal representation or an avatar for active participation or real-time interactions. The ability of different users to meet in a visual space and take part in an activity collaboratively is made possible by a host server, running applications such as virtual reality modeling language (VRML), linked to any world wide web (WWW) server, enhanced with an appropriate plugin. In addition, special preparation of the virtual space is required by the host management. A wide variety of creativity is exhibited in the type of atmosphere, the character of the builder, as well as the roles of participation. This includes limitation of access, nature of avatars, and other variables which are peculiar to the space in question. These sites are very popular for the variety of online gaming they support. Notable examples can be seen in the Activeworlds site, Sims, Alphaworlds, Starwars, and the Quake series. However, the high computing requirements limits these interactions to a select class of enthusiasts. Its potential for use in conventional planning has not yet been exploited. Virtual-to-real interaction

The interaction of virtual with real spaces is a phenomenon which makes use of proprietary technology to link virtual spaces to real spaces, either in real time or in preprocessed media. This is usually through the use of either GPS or webcam öthe two technologies operate with slightly different interfaces. GPS transmissions are based on satellite navigation, whereas webcams rely on either local area networks (LANs) or wireless application protocols (WAPs) for transmission of data. The data can be stored as references or viewed in real-time situations in order to monitor activities of one kind or another. Access to real spaces through a virtual space requires an appropriate interface, as well as the supporting technology. A notable example of this application is found in the deployment of observation cameras in the vicinity of Bunker Hill, in downtown Los Angeles. However, with regard to the adoption of this technology for monitoring urban spaces, it appears there is still some work to be done, as ``the inevitable selectivity and positioning of any surveillance eye's view entails the simultaneous production of blind spots, harboring spaces that must remain less well attended to'' (Flusty, 2000, page 157). Yet it can be argued that if a decision can be made as to which areas to cover, then this technology could actually limit the amount of manpower needed for routine surveillance. In addition, it will provide a view of any activities that eventually lead to disturbances within the urban center. A more advanced option of this category is the use of web pages running a webcam. In this case, the users can participate in real-time exchange of information. Although the use of a webcam may not be flexible enough to allow viewers to grasp the entire scope of the space in which the webcam is deployed, it does indicate a potential that can be extended to provide multiple views of activities happening simultaneously in an environment, such as outside and inside shopping centers or prayer halls, or similar locations. All that is needed is a number of synchronized views from the cameras: the viewer can then decide which to focus on from a selection of thumbnail shots. Because the technology operates in the domain of streaming media, it also provides the means of making a record of events that can be edited later through various video options. Real-to-virtual interaction

The third type of interaction that makes cross-interaction possible within an urban environment is that of virtual space with a real environment. This is the trend in the field of GIS modeling and urban analysis, whereby new designs or developments are pretested before finalization for design implementation. Other applications involve simulation for training in driving through cities, sea navigation, flight simulation, and the like. The essential benefit is the ability to bring a proposed scheme in line

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with existing situations, wherein appropriate critiques can be made. However, despite the huge advantage that can be gained from this technique, there are still some difficulties associated with the time-frame required to capture existing physical developments fully. The major challenges have to do with the fact that no appropriate means has yet been found to minimize the data resulting from representations of any urban center while at the same time providing enough detail to support such operations as comprehensive urban design without resorting to segmental storage or high compressions. In each case, the data are either difficult to manipulate or substantially deprived of much desired quality. Two outstanding projects aimed at solving these problems have been ongoing in University College London, and the University of California at Los Angeles. There have also been some recent developments in Tokyo and New York. Batty et al (2000a) identified twelve major applications, ranging from emergency response to e-commerce and tourism. The developments examined so far point to the fact that there are parallel developments in the field of planning and of management of urban systems, all aimed toward an improvement in the systems. Yet, there are hardly any modus operandi or specified standards for the coordination of the various segments. It is common for engineers to set standards for various infrastructures and to expect others to follow, or for urban economists and geographers to entwine fine theories about the best possible locations; but as long as there is no coherence, no claim can be justified. This has led other planners to embrace the much-publicized sustainable development approach as the most appropriate for the comprehensive handling of urban systems. There is certainly a degree of truism about sustainability being the way forward. At this juncture, it would not be an overstatement to say that, although sustainability is the concept most bandied around in the professional spectrum, it is actually where all research efforts in the planning environment have been converging, although this is not explicitly stated. One obvious reason seems to be a refocus on development indicators as a base for unified decisionmaking, though this is highly debatable. Sustainability and decision support The maxim in the planning environment today is `sustainability'. It is a concept that came into being in the early 1990s, in recognition of the fact that existing indicators for measuring human development lacked adequate assessment of inbuilt mechanisms guiding development across many ranges. Sustainability employs a new set of indicators to assess existing development as well as to guide future development. Its widely accepted definition reads: ``Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs'' (WCED, 1987; see Bossel, 1999). A variant of the definition embodies the aspects of reproduction, balance, dynamic process, and linking of local to global concerns: ``Sustainable development is a dynamic process in which communities anticipate and accommodate the needs of current and future generations in ways that reproduce and balance local social, economic, and ecological systems, and link local actions to global concerns'' (Berke and Manta, 1999). The advent of `sustainability' has witnessed dramatic and almost frenzied efforts on the part of some thinkers and planners to link it with mainstream planning practice. Its appeal lies in its subtle ability to integrate environmental concerns, socioeconomic challenges, and cultural dynamics with global issues of migration or the accumulation of people within urban centers. However, difficulties in its operationalization have led to various decision systems being tried out at one level or another. As a result, it has


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been found that ``communities designed and built according to sustainable principles show significant economic, social and environmental benefits'' (Pollard, 2001, page 1). However, the uniqueness of communities across most national territories makes it almost impossible to transfer the results in, or approaches used by, any sustainable community. This is why decision-support tools need to be as comprehensive as possible, though most hardly meet the challenges of population dynamism. The complexity of socioeconomic, environmental, and sociocultural dynamics is not an issue that can be handled in the conventional paper environment, as was the case before the advent of high-capacity computing. As a result, most decision-support systems (DSSs) are now computerized, with a majority of them anchored to a dedicated GIS environment. With increase in the size both of organizations and of municipal geodatabases, more and more effort is required to sustain the systems within which they operate. It is no longer the responsibility of management or of a planning team to handle or conceive and implement a development that is going to be used by a large number of people, or an entire community. As planning theories shift towards participative and collaborative approaches, the number of cases and alternatives to be examined tends to increase in both size and time frame. Yet it is required that such projects be delivered in a short time. There are two ways to address such demands. These include variants of DSSs, which are predominantly internal, and those of participative or collaborative decision-support systems (CDSSs), which are predominantly external. Although it is possible to have variants of CDSSs, they are simply extensions of DSSs, in which participation in decisionmaking is emphasized without the rigors or technicalities of DSSs. What is actually required is a setup that combines the strength of the two systems within a comprehensive system, thereby allowing both technical implementation of decisions as well as collaborative participation. Decision-support systems (DSSs) Decision-support systems have been studied for applications in many areas related to planning schemes, with most attention being paid to spatial decision-support systems (SDSSs) (see, for instance, Carsjens, 1996; Stark, 2000). The essential character of DSSs is to couple a set of processes or tools strategically such that they can be logically and chronologically employed in the solution of a problem. A flow chart is required at the outset, to establish the hierarchy of the processes involved and the devices to be employed at each stage. In addition, there are logical decisions to be made in cases of unexpected outcomes, and in terms of what the final outcome should represent. Usually a number of models are coupled together, with either strong or weak links, each with an internal flow chart. These processes have been greatly simplified with the introduction of model builders within ESRI Inc.'s GIS applications. However, various concepts are still being developed. The application of modeling for a particular desired outcome is limited only by the imagination. One such application is the use of a comprehensive set of multimedia to simulate the possibility of rendering an area that is environmentally sensitive more sustainable in the face of growing tourist numbers. The raison d'eªtre of the study resides in the fact that management of visitor behavior depends upon models that allow for interaction between visitors; changes in movement patterns, or time allocation, as a product of existing site conditions; estimation of resultant visitor-satisfaction levels, and estimation of the effect of the visitor on the site (Bishop and Gimblett, 2000). The main frame of the study relies on traditional SDSSs with the incorporation of an extension that supports a virtual environment. This extension is needed to capture the variety of behavior, simulated from the interactions of preprogrammed agent types. GIS has been adopted as the hub for anchoring various models. To evaluate the level of

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sustainability of the land parcel, interpretation of the environmental impact and satisfaction levels are necessary. The sustainability level is looped back to management at the top of the flow hierarchy (see figure 1). Although the model is an attempt to link a virtual environment with a traditional SDSS, through the hub of a GIS, it cannot be opened up to collaborative decisionmaking. At the same time, some important aspects that should have been included to act as feedback to the system, are omitted. For instance, the level of erosion, or water-quality appreciation, as a result of the action of agent types should logically form a feedback to the GIS hub for further processing, or utilization as modified data. Management options

Slope

Elevation

Vegetation

GIS hub

Built form

Virtual environment

Virtual analysis

Visitor surveys (in virtual environment) Agent type A

Erosion Water model quality Visual model impact model

Agent simulation engine

Behavioral rules

Agent type B

Agent type C Satisfaction levels

Environmental impact

Sustainability

Figure 1. Schematic model for sustainable recreation management (Bishop and Gimblett, 2000).

Collaborative decision-support systems (CDSSs) CDSSs were introduced into the planning domain in the late 1990s in response to demands from pressure groups for public participation in planning. Although their introduction is a welcome step towards ensuring the success of planning efforts, these CDSSs are concentrated largely on facilitating public participation at the expense of providing the technical background that informs such decisions. However, there are some which are technically driven, at the expense of the basic concepts that justify planning. The efforts made towards establishing CDSSs, include those of Shiffer (1992; 1995), Jankowski and Stasik (1997), Selman (2000), Ard (2000), O'Toole (2000), Nedovic¨-Budic¨ and Pinto (2000), and Ploger (2001), amongst others. The early studies of CDSSs were based on the assumption that the ordinary user has three major handicaps which inhibit access to information, and hence the ability to make an informed decision about any development relating to this information. The first handicap is the inability to make use of a computer environment. The second is the difficulties of comprehending the information because of the technical way in which this information is conceived and presented. Third, even where information is readily available, there still remains the difficulty of filtering through a vast assortment of


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media or specialist literature. Large maps, charts, and graphs are not only intimidating but also do not provide satisfactory results. It was thus argued that the use of multimedia such as documents, news clips, and interviews, could dissipate the mystery surrounding inadequate human ^ machine interface. The advocating of `pleasurable engagement' (Laurel, 1986, in Shiffer, 1992) through the introduction of visual presence and multiple representations, it was reasoned, could mask the intermediary devices and, further, serve as guided reminders. Through this approach a number of devices were developed, that could collectively, and within the same interface, present a user with plans of a proposed project site, proposed images, and navigation tools as well as optional background sound. Through this medium, a number of alternative plans could be scored by simply pointing and sliding horizontal bars. This was a welcome development, yet it would take another couple of years before the Windows operating systems became operational on the global network. The additional advantage provided by the global network gave more impetus to the development of CDSSs. This was given various connotations, for instance, collaborative planning systems (CPS), spatial understanding and decision support systems (SUDSS), collaborative spatial decision making (CSDM), and multicriteria decisionmaking (MCDM). The names had little or nothing to do with the fact that all of these developments were geared towards sharing information across the global network. Rather, it seems that this proliferation of names reflected the lack of a unified focus on the creation of a comprehensive system which would operate with the same interface, irrespective of the platform it was running on. In this way, planning can be considered as a reflection of power; with participation and collaboration a reflection of knowledge and empowerment. Or, a representation of both subtle and lethal forces that can be used abusively to subjugate the governed or, conversely, used in overcoming formal governance (Ploger, 2001). In design and implementation use was made of four different arrangements, which, according to Jankowski and Stasik (1997) included: (1) the same location and time; (2) the same location and a different time; (3) different locations and the same time; and (4) different locations and different times. Again, in this case the main hub was a GIS setup that could conveniently provide integration of spatial and aspatial data. To enhance this, Windows graphic user interfaces (GUIs), displaying multiple views, were employed in cases where it would have been difficult to switch between various views for analysis or simple queries. Comprehensive implementation studies were carried out in the mid-1990s (see Shiffer, 1995) toward a detailed demonstration of the ability of such systems. The integration of sound, visual effects, and accurate 3D representations with simulated motion helped concretize the acceptance of the systems within the larger planning public. Figure 2 (see over) shows the layout of the network environment through which pleasurable interaction is possible. Such layouts can be used for both small and large-scale applications. Small-scale implementation

Ironically, direct implementations of such systems have not been seen in professional planning sector. Once the idea was sufficiently grounded, a number of firms or companies took up the challenge of providing various municipalities with packaged GIS hypermedia environments to enable them to make decisions regarding land-development and other relevant issues. Pioneering this new phase of collaborative decision are companies such as IT Spatial LLC, and Evans & Sutherland (E & S). In a scheme developed for Arlington County, Virginia, IT Spatial came up with a scheme which allows any person to access a 3D database for a number of queries, with the aid of a dynamic connection between a 2D GIS base and a 3D database. The interesting achievement of

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Data Digital

GIS coverages

Hard copy and video tape

Databases

Field trip data (video, sketches, other observations)

Hard copy documents Images

Digital conversion of data

Access and storage of data

CAD files

Network UNIX Work stations

Macintosh or PC with conversion software

Imaging software

CAD software

Archiving of digital data

Slide scanner

Digitizers

Document scanner

Camcorder

Cataloguing for sustained use

Direct insertion of digital data into CPS

Database management system

Automated data extraction for use with CPS modules

Geographic information systems

Collaborative planning systems (CPS) (Networked laptop or microcomputer) Hardware

Software Data manipulation tools Annotation tools

Representational aids Navigation tools

Central processor/ keyboard

storage device/ pointing device

Microphone/audiovisual displays

Figure 2. Concept diagram and flow for collaborative planning systems (from Shiffer, 1995).

the scheme is the provision of an accurate photo-realistic 3D database of an area covering approximately half a square kilometer. In addition to this, various engineering drawings of proposed developments can be downloaded for further examination. Also available is a discussion site, where any person interested in the proposed developments can read as well as place comments. What seems lacking in the scheme, though, is an implied utilization of DSS for the internal regulation of planning or development schemes. In all other respects its benefits are substantial. Similar to the Arlington Scheme of IT Spatial is the undertaking of E & S, a 3D specialist of note in the field of collaborative decision-support systems development. The company's top-of-the-range product is its RAPIDsite software, which is geared


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towards the analysis of any proposed development. The system is anchored to a GIS hub and provides support for visual impact analysis needs in the development approval process. Although E & S's RAPIDsite provides a smart solution to the modeling of 3D entities, its compatibility with CDSSs has yet to be shown; the compatibility of the IT Spatial system has already been demonstrated. The potential of RAPIDsite as the fastest and most affordable 3D modeler, with varied outputs, will go a long way to concretize the development of collaborative decision-support systems which increasingly require such functions for enhanced communication. This is even more demanding in the case of large-scale implementation. Large-scale implementation

The development of a comprehensive framework for CDSSs requires some knowledge of the constituent elements that go into making such frameworks. In addition, it is useful to know, the end users, the extent of interactivity required, and the operating environments, even though some occasional structuring is required to maintain the systems. One of the earliest examples of systems which were attempts to couple powerful GIS bases with visualization can be found in the works of Batty, written during the late 1990s. The venue project summarizes his long association with decision-support systems and the visual display of urban systems. Not only does the project provide details of the implementation of the various combinations of GIS with display and analytical tools, but also it outlines the flow of a logical link between the traditional models of urban systems, and those derived from developing techniques, such as space syntax and others. Figure 3 shows the approach adopted in the venue project, and the established links of emerging models with GIS. Start

Problem definition

Behavioral

Data collection

Socioeconomic Data analysis

Functional Physical

Objectives GIS Tool kit

Syntax

Network

Maps

Photo

Draw edits

CAD

2D to 3D

Evaluation of plans

CAD models

Testing of plans

Functional models Economic models

Analysis of solutions

Generation of plans

Choice of best plan

Figure 3. Schematic model of computer systems (Batty et al, 2000b).

Implementation

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Building an enterprise-wide GIS An enterprise-wide GIS provides a preferred hub for any network system that is designed to provide support for a CDSSs. Its ability to handle spatial and aspatial data, alongside comprehensive geodatabases in addition to other extensions, is a considerable advantage over other graphic or analysis systems. These high-end potentials have enabled the firm of St George Consulting (Kroot, 2000) to deploy an enterprise-wide GIS for the US Department of Environmental Protection (DEP). Its involvement with iterative software development puts it in direct contact with the public for the validation of prototypes. Because each prototype has to be verified against the particular model by end users a number of times before final deployment, it requires a very robust network to support collaborative decisionmaking. The end result provides universal access to data and projects, data sharing amongst employees, as well as the ability to edit and analyse, etc. St-George-Consulting views its product as virtually perfect. However, their elimination of ArcView and ArcIMS may not sit well with most municipal organizations which use the Internet as an exclusive means of providing maps to their clients or to the general public. In addition, the absence of ArcPAD does not seem to answer some of the challenges of the widely distributed networking requirement of a varied public which may wish to sample the products of the DEP. Nonetheless, it is a welcome development which provides a lot of insight into the deployment of an enterprise-wide GIS. Growth-allocation models built with GIS

Growth-allocation models are not new in GIS applications per se. However, because of the variability of the end users and the technical requirements involved in the development of a given model, the range and extent of the performance often differ from case to case. In the case of the model developed jointly by the Metropolitan Planning Organization (METROPLAN) for Orlando, Florida, and Canin Associates, a Florida-based property development company), the aim is the development of socioeconomic data projection for a number of counties. As in the case of the Arlington County Scheme, it is anchored on a GIS hub. In addition, it must provide a suitable avenue for public participation in overall planning in the region. There was also a need to include the timing of development, an inventory of available land, details of demand and trends of private development, as well as factors affecting site feasibility. The development of the model again calls for some consideration of the direct participation of end users in the decisionmaking mechanism of the database. Its absence may be an oversight on the part of the development team; or, of course, this may have been the intention. A spatial understanding support system for conflict resolution

This model was developed in an attempt to increase the scope of spatial understanding support systems (SUSSs), through the interface of soft operation research (SOR). It is widely referred to as CRANES (coordinator for rational arguments through nested substantiation) (Horita, 2000). Its ability to meet the demands of a large user base and complex problems has been successfully tested in a number of cases in the United Kingdom. The results obtained in each case have proven well above average. The system is anchored on a GIS setup that displays multiple pages on screen. Its application to the conflict over the construction of a community learning center at Gospel Oak, London, showed that, in addition to clarifying the arguments over establishing the center, it did help people reach logical conclusions. This was possible through the use of structured pages enabling arguments to be related to the geographical location on maps and drawings, as well as to others' opinions on the various scenarios being debated. The overall scheme showed a degree of enablement


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of collaborative participation, with a strong visual capacity. However, there is room for improvement for initiating planning or modifying an ongoing scheme. It does not provide any countercyclical approach to problem reassessment, as other systems have attempted öespecially in the case of professional collaboration. Concluding discussion: towards a holistic urban approach The various approaches that have to date formed a base for conventional planning tend to be rather idiosyncratic in nature. Similarly, a wide variety of decision-support systems has been developed. The advent of sustainability has not helped, having added another perspective to the challenges of planning. Yet, in the face of the crucial issues segmenting urban centers, compromising governance, and misleading planning efforts, there ought to be a more elaborate approach to addressing the challenges. There now seems to be strong need, if not a desperate call, for a holistic system which will allow an organization or municipality comprehensive coverage of the entire scope of activities under its jurisdiction öone that brings together the various components that make up an urban setup. By linking all development concerns to a highly powerful geodatabase, alongside analytical capability and external connectivity, both collaboration and participation in planning should be ensured. Were we to theorize on such systems, they would require both subtle and tangible couplings. At the outset, the system must allow for the generation and manipulation of a large geodatabaseödirectly or indirectly linked to multiple visual displays. It should be empowered with at least three major components, covering sustainable development, decision-support mechanisms, and the virtual environment, all with flexibility of interchange and sharing interfaces. The rationale for this is that, when taken as a single system, it should immediately lend itself to the challenges of complex systems. This can then, hopefully, bridge the divide between infrastructure-oriented planning and land use based approaches which are, after all, interrelated. A number of the systems examined manifest a leaning towards such systems. The DEP and METROPLAN show potential that can be built upon. However, they remain biased toward certain conceptual and analytical approaches, including sociocultural dynamism, socioeconomic potentials, environmental constraints, and the choice of decision-support mechanism. An ideal system should be able to be articulated around the interface of GIS or similar systems. It should simultaneously act as an anchor both for virtual and for visual analysis. Such a comprehensive setup will allow for broader collaboration and participation in decisionmaking, than in the idiosyncratic models examined. As has been shown, innovative developments in urban systems, changing perspectives of land use, and a growing entrepreneurship are defining forces in the shaping of urban centers and the way human interactions are lubricated and regulated. Though the benefits of such developments have been shown to be enormous, their negative impacts may be equally destabilizing. Narrowing of the class gap, the stamping out of social ills, and the sustenance of social dynamics cannot be achieved by separatist or exclusive platforms. Rather, a more conscientious policy framework is required that unifies the planners and the planned, governance and the governed, consumers and entrepreneurs, and, above all, the environment and development. This has been shown to be possible within some communities. However, as long as these aims are not comprehensively fulfilled there will still be destitution, exploitation, and marginalization on the one hand, and affluence, the continuous quest for ideals, security, and progress on the other; but in the end it will become clear that the haves and have nots cannot exist as separate entities within the same spatial system. The challenges for planning are even greater, given the increasing complexities of spatial systems,

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propounded concepts, and increasing adverse computational power. We recommend a unified focus that draws on the various reactionary concepts now being practiced as well as those still being developed. How they should be brought together is an open question but a worthwhile one for decisionmakers. Acknowledgements. Thanks are due the King Fahd University of Petroleum and Minerals for support and the provision of a conducive atmosphere for undertaking the research work for this paper. The authors also acknowledge the assistance of those who kindly granted permission for use of illustration from their works; and the referees, for their very helpful and stimulating reaction to an earlier version of this paper. References Ard R, 2000, `Èffective three-dimensional visualization technology supports both ESRI GIS and CAD: new software helps speed the proposed development approval process'', http:// gis.esri.com/library/userconf/proc00/professional/abstracts/a379.htm Batty M, 2000a, ``The new urban geography of the third dimension'' Environment and Planning B: Planning and Design 27 483 ^ 484 Batty M, 2000b, `` À slow of sort of country!' said the Queen'' Environment and Planning B: Planning and Design 27 799 ^ 800 Batty M, Dodge M, Jiang B, Smith A, 2000b, ``New technologies for urban designers: the venue project'', http://www.casa.ucl.ac.uk/venue.pdf Batty M, Doyle S, Chapman D, Evans S, Haklay M, Kueppers S, Shiode N, Smith A, Torrens P M, 2000a, ``Visualizing the city: communicating urban design to planners and decision makers'', http://www.casa.ucl.ac.uk/visualcities.pdf Berke P, Manta M, 1999, ``Planning for sustainable development: measuring progress in plans'', working paper, Lincoln Institute of Land Policy, http://www.lincolnInst.edu/workpap1 Berkoz L, 2000, ``Location of financial, insurance and real estate firms in Istanbul'' Journal of Urban Planning and Development 6 75 ^ 88 Bertolini L, 2000, ``Planning in the borderless city: a conceptualization and an application to the case of station area redevelopment'' Town Planning Review 71 455 ^ 474 Bishop I D, Gimblett H R, 2000, ``Management of recreational areas: GIS, autonomous agents, and virtual reality'' Environment and Planning B: Planning and Design 27 423 ^ 435 Bossel H, 1999 Indicators for SD: Theory, Methods, and Applications a Report to the Balatan group, International Institute for Sustainable Development, Winnipeg, Manitoba Carsjens G J, 1996, `Ànalysis and decision support of land use allocation problems'' Journal of Geographic Information and Decision Analysis 1 1 ^ 8 Cowen P B, Tynan N, 1999, ``Reaching the urban poor with private infrastructure'', Public Policy for the Private Sector, note 188, The World Bank, Washington, DC de Roo G, 2000, `Ènvironmental conflicts in compact cities: complexity, decisionmaking, and policy approaches'' Environment and Planning B: Planning and Design 27 151 ^ 162 Dutta S, 2000, `Èlectronic commerceöthe market of the future'' Deutschland 3 (6/7) 20 ^ 25 Fingleton B, 2000, ``Spatial econometrics, economic geography, dynamics and equilibrium: a `third way?' '' Environment and Planning A 32 1481 ^ 1498 Flusty S, 2000, ``Trashing downtown: play as resistance to the spatial and representational regulations of Los Angeles'' Cities 17 149 ^ 158 Graham S, 2000, ``Construction premium network spaces: reflection on infrastructure networks and contemporary urban development'' International Journal of Urban and Regional Research 24 183 ^ 200 Horita M, 2000, ``Mapping policy discourse with CRANES: spatial understanding support systems as a medium for community conflict resolution'' Environment and Planning B: Planning and Design 27 801 ^ 814 Jankowski P, Stasik M, 1997, ``Design consideration for space and time distributed collaborative spatial decision making'' Journal of Geographic Information and Decision Analysis 1 1 ^ 8 Kaiser E, Godschalk D, Chapin S, 1995 Urban Land Use Planning 4th edition (University of Illinois Press, Chicago, IL) Kroot C, 2000, ``Building an enterprise wide GIS using ArcInfo 8.0, Oracle, and Citrix'', http://gis.esri.com/library/userconf/proc00/professional/papers/PAP600/p600.htm Laurel B, 1986, `Ìnterface as mimesis'', in User Centered System Design: New Perspectives on Human Computer Interaction Eds D A Norman, S W Draper (Lawrence Erlbaum, Hillsdale, NJ) pp 67 ^ 86


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