In this paper we present a web-based platform that makes use of HTML5 technology and WebGL to facilitate public participation in urban planning. It consists of components that enable city administrations to present urban plans to the public and to engage with stakeholders. One of these components uses the open source library X3DOM to visualise 3D content-for example, a city model containing a 3D representation of a planned building. Since X3DOM does not need additional software to be installed on the user's system our implementation is more portable than previous work. Our solution is based on the open source software Liferay which allows it to be configured for various urban planning projects. In order to enable communication between different web application components residing in inline frames (iframes) we implemented a special message bus based on HTML5 postMessage. In this paper we describe implementation details, but we also intensively discuss the possibilities of modern web technology for urban planning. We motivate the use of such technology through three examples that can be implemented using our web application. In this paper we also present results from evaluating our application in user workshops carried out within the project urbanAPI that is funded by the European Commission. Finally, we draw conclusions and discuss possibilities for future urban planning use cases

Citizen participation for social innovation and co-creating urban regeneration proposals can be greatly facilitated by innovative IT systems. Such systems can use Open Government Data, visualise urban proposals in 3D models and provide automated feedback on the feasibility of the proposals. Using such a system as a communication platform between citizens and city administrations provides an integrated top-down and bottom-up urban planning and decision-making approach to smart cities. However, generating automated feedback on citizens' proposals requires modelling domain-specific knowledge i.e., vocabulary and rules, which can be applied on spatial and temporal 3D models. This paper presents the European Commission funded H2020 smarticipate project that aims to achieve the above challenge by applying it on three smart cities: Hamburg, Rome and RBKC-London. Whilst the proposed system architecture indicates various innovative features, a proof of concept of the automated feedback feature for the Hamburg use case 'planting trees' is demonstrated. Early results and lessons learned show that it is feasible to provide automated feedback on citizen-initiated proposals on specific topics. However, it is not straightforward to generalise this feature to cover more complex concepts and conditions which require specifying comprehensive domain languages, rules and appropriate tools to process them. This paper also highlights the strengths of the smarticipate platform, discusses challenges to realise its different features and suggests potential solutions.

Today’s politicians are confronted with new information technologies to\ud tackle complex decision-making problems. In order to make sustainable decisions,\ud a profound analysis of societal problems and possible solutions (policy options)\ud needs to be performed. In this policy-analysis process, different stakeholders are\ud involved. Besides internal direct advisors of the policy makers (policy analysts),\ud external experts from different scientific disciplines can support evidence-based decision making. Despite the alleged importance of scientific advice in the policy-making\ud process, it is observed that scientific results are often not used. In this work, a concept\ud is described that supports the collaboration between scientists and politicians. We propose a science–policy interface that is realized by including information visualization in the policy-analysis process. Therefore, we identify synergy effects between\ud both fields and introduce a methodology for addressing the current challenges of\ud science–policy interfaces with visualization. Finally, we describe three exemplary\ud case studies carried out in European research projects that instantiate the concept of\ud this approach

<p><strong>Abstract.</strong> We show an approach how to provide computed feedback on citizens’ proposals based on open data and expert knowledge in urban planning and public participation by using Domain-Specific Languages (DSL). We outline the process involving different stakeholders of engineering such a DSL and provide an architecture capable of executing the language and uploading new scripts at runtime. A real-world example of the city of Hamburg is used to show the principles and serves as input for development. A prototype has been implemented and evaluated at various events involving citizen and city representatives. We conclude that DSLs can be successfully applied to enable a new way to access data in a more convenient and understandable form, abstracting from technical details and focusing on domain aspects.</p>