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Effects of urban trees on local outdoor microclimate: synthesizing field measurements by numerical modelling

Force-Based Self-Organizing MANET/FANET with a UAV Swarm

This paper introduces a novel distributed algorithm designed to optimize the deployment of access points within Mobile Ad Hoc Networks (MANETs) for better service quality in infrastructure less environments. The algorithm operates based on local, independent execution by each network node, thus ensuring a high degree of scalability and adaptability to changing network conditions. The primary focus is to match the spatial distribution of access points with the distribution of client devices while maintaining strong connectivity to the network root. Using autonomous decision-making and choreographed path-planning, this algorithm bridges the gap between demand-responsive network service provision and the maintenance of crucial network connectivity links. The assessment of the performance of this approach is motivated by using numerical results generated by simulations.

Maturity of Operational Procurement in the Construction Industry: A Business/IT-Alignment Perspective

From the article: "Project execution in the construction industry faces major challenges, e.g. difficulty in coordination and cooperation. Operational procurement during project execution is no exception. In this paper we construct a maturity model, based on earlier work, consisting of six dimensions (goal, control, process, organization, information, technology) and five maturity stages (transactional-oriented, commercial-oriented, coordination, internal-optimized, external-optimized). The model can be used to determine the level of procurement maturity for each of the dimensions, and for the determination of a strategy for growth in the construction industry. With input from a major construction firm in the Netherlands, through simulating tooling, the model is evaluated for its contribution to growth in operational excellence. Results of the simulation show support for a relation between maturity growth and increased operational excellence." Recommended Citation Xing, Xiaochun; Versendaal, Johan; van den Akker, Marjan; and De Bevere, Bastiaan, "Maturity of Operational Procurement in the Construction Industry: A Business/IT-Alignment Perspective" (2011). BLED 2011 Proceedings. Paper 22. http://aisel.aisnet.org/bled2011/22 Affiliation: Xing Xiaochun - Swets Information Services, Netherlands; Johan Versendaal - Utrecht University, Netherlands; HU University of Applied Sciences, Netherlands; Marjan van den Akker - Utrecht University, Netherlands; Bastiaan De Bevere - Ballast Nedam, Netherlands.

The urban network game

In a thriving, densely populated and urbanized country like the Netherlands, space is at a premium. With the steady economic growth of the 1990s and the construction and expansion of homes, business parks and infrastructure, the available space and the environment are coming under increasing pressure. Major changes are also taking place on an administrative level in the Netherlands. In some cases, influential new joint ventures are formed between public, private, and social parties (Frieling 2000). The social and administrative dynamic, and the tension that this creates in relation to spatial quality requirements, is turning into a major challenge for spatial policy. Numerous advisory bodies and policymakers are therefore advocating a spatial development policy (WRR 1998) or development planning (VROM 2001, 2002). Development planning is the opposite of admittance planning and provides increased scope for the initiatives and investments of local governments and private and social parties. Instead of passively resisting activities and exhibiting too little flexibility, governments must aim at actively entering into partnerships with other governments, the business sector, and social organizations. Together, they must develop and realize interrelated, creative concepts, projects, and programs (WRR 1998; Healey 2000;Teisman 1997;VROM Council 2001). According to the Netherlands' Ministry of Housing, Spatial Planning, and the Environment (VROM 2002), development planning requires: "active intervention by means of investments made by both public and private parties. The State shall then provide policy frameworks for the investments and harmonize them with each other. This provides scope for the initiatives of lower governments, market parties, and social organizations and supports them." Innovation, future orientation, integral concepts, stakeholder planning and new ways of public private financing, and cooperation are some of the relevant characteristics ascribed to development planning. However, the above description shows that development planning may be an interesting concept but it is also very abstract and ambiguous. Moreover, the real question is how development planning works in practice and whether it actually differs from admittance planning. How can such notions as stakeholder planning, future orientation, and innovation be realized in a region? How do spatial investments, innovation, and integral concepts come about? Does development planning really result in spatial and administrative innovation, as one would expect in theory? What is clear, however, is that development planning will have to be tackled by governments and private and social parties on a regional/provincial level. Against this background, the Netherlands Institute for Spatial Research (RPB), established on 1 January 2002, asked the Delft University of Technology to design a simulation game in which the concept of development planning can be tested in a safe environment (Mayer and Veeneman 2002; Mayer et al. 2004).

Understanding Clock Gene Regulation by Constructing a Qualitative Representation

We developed a lesson where students construct a qualitative representation to learn how clock genes are regulated. Qualitative representations provide a non-numerical description of system behavior, focusing on causal relation-ships and system states. They align with human reasoning about system dy-namics and serve as valuable learning tools for understanding both domain-specific systems and developing broader systems thinking skills.The lesson, designed for upper secondary and higher education, is imple-mented in the DynaLearn software at Level 4, where students can model feedback loops. Students construct the representation step by step, guided by a structured workbook and built-in support functions within the software. At each step, they run simulations to examine system behavior and reflect on the results through workbook questions. To ensure scientific accuracy, the representation and workbook were evaluated by domain experts.The lesson begins with modeling how increasing BMAL:CLOCK activity enhances the transcription of PER and CRY genes through binding to the E-box. Next, students explore how mRNA production and degradation—two opposing processes—regulate mRNA levels. This is followed by modeling translation at the ribosomes, where PER and CRY proteins are synthesized and subsequently degraded, again illustrating competing regulatory process-es. Students then model how PER and CRY proteins form a complex that translocates to the nucleus, inhibiting CLOCK:BMAL binding and establish-ing a negative feedback loop. Finally, they extend their understanding by ex-ploring how CLOCK:BMAL also regulates the AVP gene, linking clock genes to broader physiological processes.

Combining ecosystem modeling with serious gaming in support of transboundary maritime spatial planning

The Maritime Spatial Planning (MSP) Challenge simulation platform helps planners and stakeholders understand and manage the complexity of MSP. In the interactive simulation, different data layers covering an entire sea region can be viewed to make an assessment of the current status. Users can create scenarios for future uses of the marine space over a period of several decades. Changes in energy infrastructure, shipping, and the marine environment are then simulated, and the effects are visualized using indicators and heat maps. The platform is built with advanced game technology and uses aspects of role-play to create interactive sessions; it can thus be referred to as serious gaming. To calculate and visualize the effects of planning decisions on the marine ecology, we integrated the Ecopath with Ecosim (EwE) food web modeling approach into the platform. We demonstrate how EwE was connected to MSP, considering the range of constraints imposed by running scientific software in interactive serious gaming sessions while still providing cascading ecological feedback in response to planning actions. We explored the connection by adapting two published ecological models for use in MSP sessions. We conclude with lessons learned and identify future developments of the simulation platform.