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The European Foundation for the Improvement of Living and Working Conditions has commissioned a research project to analyse the impact of flexible employment policies and human resources management on working conditions at the corporate level. Research institutes of seven countries participate in this project. For each country two or three cases are studied of organisations applying different flexible employment solutions. The seven countries are: Finland, France, Germany, Italy, Spain, The Netherlands and The United Kingdom. In this report the results of the Dutch case study are described. Two cases were studied: a company producing and selling sweets and a regional bus company. The main method of investigation was interviewing the personnel managers responsible for the flexible personnel situation in the organisation. Because of the current flexibility situation in the Netherlands, in which a new Law on flexibility and job security is enforced, two temporary employment agencies that supply these organisations with temporary personnel were also asked to participate in the study. The regional manager and the contract manager of the local agency office that delivers agency workers to the manufacturing industry and the general manager of the agency delivering personnel to the bus company agreed to participate. In addition, agency workers that work for these employment agencies in the two companies were interviewed by telephone.

Obligations can apply to individuals, either severally or collectively. When applied severally, each individual or member of a team is independently responsible to fulfill the obligation. When applied collectively, it is the group as a whole that becomes responsible, with individual members sharing the obligation. In this paper, we present several variations of common teamwork models involving the performance of collective obligations. Some of these rely heavily on a leader to ensure effective teamwork, whereas others leave much room for member autonomy. We strongly focus on the implementation of such models. We demonstrate how KAoS policies can be used to establish desired forms of cooperation through regulation of agent behavior. Some of these policies concern invariant aspects of teamwork, such as how to behave when a leader is present, how to ensure that actions are properly coordinated, and how to delegate actions. Other policies can be enabled or disabled to regulate the degree of autonomy of the team members. We have implemented a prototype of a Mars-mission scenario that demonstrates varying team behavior when applied across these different teamwork models. © Springer-Verlag Berlin Heidelberg 2010.

Engelse versie: Strategy for the nineties

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This paper presents the architecture and framework for a policy based QoS control in a shared medium type of network such as Ethernet. QoS is achieved by a combination of traffic engineering of bandwidth pipes, priority scheduling of traffic at network nodes and controlled access to the bandwidth pipes in broadband access networks.

Flexibility of management is an important requisite for access control systems as it allows users to adapt the access control system in accordance with practical requirements. This paper builds on earlier work where we defined administrative policies for a general class of RBAC models. We present a formal definition of administrative refinement and we show that there is an ordering for administrative privileges which yields administrative refinements of policies. We argue (by giving an example) that this privilege ordering can be very useful in practice, and we prove that the privilege ordering is tractable. © Springer-Verlag Berlin Heidelberg 2007.

Santiago (33.5°S, 70.5°W), the capital of Chile, is frequently affected by extreme air pollution events during wintertime deteriorating air quality (AQ) and thus affecting the health of its population. Intense residential heating and on-road transport emissions combined with poor circulation and vertical mixing are the main factors responsible for these events. A modelling system composed of a chemistry-transport model (CHIMERE) and a meteorological model (WRF) was implemented to assess the AQ impacts of residential and transportation sources in the Santiago basin. A two-week period of July 2015 with various days with poor AQ was simulated focusing on the impact on AQ with respect to fully inhalable particles (PM2.5) and nitrogen oxides (NOX). Three emission scenarios, within the range of targeted reductions of the decontamination plan of Santiago, were tested; namely 50% reduction of residential emission, 50% reduction of transport emissions and the combination of both. An additional scenario decreasing transport emissions in 10% was carried out to examine whether a linear dependence of surface concentrations on changes in emissions exists. The system was validated against surface and vertically resolved meteorological measurements. The model reproduces the daily surface concentration variability from the AQ monitoring network of Santiago. However, the model not fully captures the emissions variations inferred from the observations which may be due to missing sources such as resuspension of dust. Results show that, during the period studied, although both residential and transportation sources contribute to observed AQ levels in Santiago, reducing transport emissions is more effective in terms of reducing the number of days with pollution events than decreasing residential combustion. This difference in impact is largely due to the spatial distribution of the emission sources. While most of the residential combustion is emitted in the outskirts of the city, most of the transport emissions occur within the city, where most of the stations from AQ monitoring network of Santiago are located. As can be expected, the largest improvement of AQ in Santiago is achieved by the combined reduction of emissions in both sectors. Sensitivity analysis with 10% reduction in transport emissions reveals a linear behavior between emissions and concentrations for NOX and approximate linear behavior for PM2.5. The absence of secondary aerosols formation and dust resuspension in the current simulation could explain this deviation from linearity for fine particles. Nevertheless, it suggests that the results can be used for mitigation policies with emissions reductions below the 50% used in this study. © 2018 Elsevier Ltd

In this study, we identify spatial regions based on an empirical data set consisting of time-dependent origin-destination (OD) pairs. These OD pairs consist of electronic traces collected from smartphone data by Google in the Amsterdam metropolitan region and is aggregated by the volume of trips per hour at neighbourhood level. By means of community detection, we examine the structure of this empirical data set in terms of connectedness. We show that we can distinguish spatially connected regions when we use a performance metric called modularity and the trip directionality is incorporated. From this, we proceed to analyse variations in the partitions that arise due to the non-optimal greedy optimisation method. We use a method known as ensemble learning to combine these variations by means of the overlap in community partitions. Ultimately, the combined partition leads to a more consistent result when evaluated again, compared to the individual partitions. Analysis of the partitions gives insights with respect to connectivity and spatial travel patterns, thereby supporting policy makers in their decisions for future infra structural adjustments. © 2019, The Author(s).

The city logistics system faces serious challenges in the near future, such as zero-emission transport in city centers and the decarbonization of urban freight transport to meet the climate agreements. The city logistics system is in itself a very heterogenous system with many different types and forms of logistics operations. The use of battery electric freight vehicles (EFVs) could be a solution to make urban freight transport more sustainable. However, the relatively high procurement costs for an EFV – especially for the vehicles heavier than 3.5 tons – in comparison to the currently often used diesel vehicles, the lack of availability of OEM-produced vehicles, and the relatively short range compared to the currently used diesel vehicles, are challenging in actually using EFVs on a large scale in daily city logistics operations. This paper identifies the main trends and developments influencing city logistics and breaks down the city logistics system in six main segments. Using a TCO comparison between conventional and electric freight vehicles, we identify for which segments battery electric freight vehicles can be expected to be feasible alternative on the short time (and what barriers should be resolved in order to increase feasibility. The analyses follow from real-life demonstrations, of EFVs in city logistics operations in the project FREVUE.

In this paper we introduce a new framework for controlling compliance to discretionary access control policies [Cederquist et al. in Proceedings of the International Workshop on Policies for Distributed Systems and Networks (POLICY), 2005; Corin et al. in Proceedings of the IFIP Workshop on Formal Aspects in Security and Trust (FAST), 2004]. The framework consists of a simple policy language, modeling ownership of data and administrative policies. Users can create documents, and authorize others to process the documents. To control compliance to the document policies, we define a formal audit procedure by which users may be audited and asked to justify that an action was in compliance with a policy. In this paper we focus on the implementation of our framework. We present a formal proof system, which was only informally described in earlier work. We derive an important tractability result (a cut-elimination theorem), and we use this result to implement a proof-finder, a key component in this framework. We argue that in a number of settings, such as collaborative work environments, where a small group of users create and manage document in a decentralized way, our framework is a more flexible approach for controlling the compliance to policies. © Springer-Verlag 2007.

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Multi-Level Security (MLS) is often viewed as the holy grail of information security, especially in those environments where information of different classifications is being processed. In this paper we argue that MLS cannot facilitate the right balance between need-to-protect and duty-to-share as required for a Network Enabled Capability (NEC) based military operations. This is due to the fact that MLS is deemed rigid in its restrictions; it obstructs the flow of information towards lower classifications by definition and thus influences duty-to-share; furthermore MLS results in a set of rigid preconditions for the physical environment to guarantee the required need-to-protect. The focus of a security solution instead should be on flexibility towards information sharing and reducing risks to be useful in a NEC environment. This can be achieved by firstly reducing the size (and complexity) of the systems that contain the classified information systems, using Multiple Independent Levels of Security (MILS) to create these smaller, separated compartments; and secondly controlling the information flow between the (different) classified compartments by dynamic policies. Moreover, the realignment of classification provisions can make management of information much more flexible and efficient. Hence, we can finally forget MLS.

In this paper we consider the runtime service adaptation mechanism for service compositions that is based on conditional retries. A single retry may be issued while a concrete service within composition is executed. This retry could either invoke the same concrete service or a functionally equivalent service implementing the same task. We determine the optimal moments to terminate the current request and replicate it. The calculation of these moments for each task within the workflow is based on different QoS parameters from Service Level Agreements, like services' response-time distributions and cost-relating parameters. The calculations are performed taking into account the remaining actual time-to-deadline, and the benefit of conditional retry mechanism is illustrated by simulations. We further discuss the impact of costs and response-time distributions' parameters to the solution at hand. © 2012 Springer-Verlag.

Geleuidhinder is na luchtverontreiniging het grootste milieuprobleem voor de volksgezonheid. De meeste hinder wordt veroorzaakt door het wegverkeer. Maar liefst 3 miljoen mensen in Nederland zijn gehinderd of slaap gestoord. Ernstig gehinderd of slaapgestoord zijn bijna 1,5 miljoen mensen. Verlaging van de bron-niveaus van de voertuigen en banden is, met stille wegdekken, de meest kosteneffectieve manier om daar wat aan te doen.

The European project - HealthyAir is a network project involving six institutions in Europe on actions and activities that address the effects of construction products on indoor air. Different ways to improve indoor air quality were reviewed, ranging from source control to education of occupants on how to manage the built environment to achieve healthy and acceptable indoor air. Through literature study, organised workshops with scientific experts and building professionals as well as via interviews with three stakeholder groups: producers of construction products, architects and housing corporations; requirements for information, guidance and actions to improve indoor air quality were identified. These requirements formed the basis of a possible approach to improve indoor air quality: education and awareness, regulations and policies and further research and development. © 2010 SAGE Publications.

Due to the inherent stochastic nature of services execution environment within service oriented systems, a runtime adaptation of the given composition may be required. We address a runtime service adaptation mechanism based on conditional retries for the orchestrated web services. The conditional retry may be issued while a concrete service within composition is executed. The retry could either invoke the same concrete service or a functionally equivalent web service that implements the same task. We use dynamic programming to determine the optimal time instances at which the current request should be terminated before request replication. The calculation takes into account different QoS parameters like services' response - time distributions and cost - relating parameters, and the solution optimizes the expected revenue of composite service provider. We illustrate the benefits of our approach by numerical calculations, and discuss the impact of considered QoS parameters to the solution at hand. © 2013 IEEE.

Well-being impact assessments of urban interventions are a difficult challenge, as there is no agreed methodology and scarce evidence on the relationship between environmental conditions and well-being. The European Union (EU) project “Urban Reduction of Greenhouse Gas Emissions in China and Europe” (URGENCHE) explored a methodological approach to assess traffic noise-related well-being impacts of transport interventions in three European cities (Basel, Rotterdam and Thessaloniki) linking modeled traffic noise reduction effects with survey data indicating noise-well-being associations. Local noise models showed a reduction of high traffic noise levels in all cities as a result of different urban interventions. Survey data indicated that perception of high noise levels was associated with lower probability of well-being. Connecting the local noise exposure profiles with the noise-well-being associations suggests that the urban transport interventions may have a marginal but positive effect on population well-being. This paper also provides insight into the methodological challenges of well-being assessments and highlights the range of limitations arising from the current lack of reliable evidence on environmental conditions and well-being. Due to these limitations, the results should be interpreted with caution. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

Background: Climate change is a global threat to health and wellbeing. Here we provide findings of an international research project investigating the health and wellbeing impacts of policies to reduce greenhouse gas emissions in urban environments. Methods: Five European and two Chinese city authorities and partner academic organisations formed the project consortium. The methodology involved modelling the impact of adopted urban climate-change mitigation transport, buildings and energy policy scenarios, usually for the year 2020 and comparing them with business as usual (BAU) scenarios (where policies had not been adopted). Carbon dioxide emissions, health impacting exposures (air pollution, noise and physical activity), health (cardiovascular, respiratory, cancer and leukaemia) and wellbeing (including noise related wellbeing, overall wellbeing, economic wellbeing and inequalities) were modelled. The scenarios were developed from corresponding known levels in 2010 and pre-existing exposure response functions. Additionally there were literature reviews, three longitudinal observational studies and two cross sectional surveys. Results: There are four key findings. Firstly introduction of electric cars may confer some small health benefits but it would be unwise for a city to invest in electric vehicles unless their power generation fuel mix generates fewer emissions than petrol and diesel. Second, adopting policies to reduce private car use may have benefits for carbon dioxide reduction and positive health impacts through reduced noise and increased physical activity. Third, the benefits of carbon dioxide reduction from increasing housing efficiency are likely to be minor and co-benefits for health and wellbeing are dependent on good air exchange. Fourthly, although heating dwellings by in-home biomass burning may reduce carbon dioxide emissions, consequences for health and wellbeing were negative with the technology in use in the cities studied.Conclusions: The climate-change reduction policies reduced CO2 emissions (the most common greenhouse gas) from cities but impact on global emissions of CO2 would be more limited due to some displacement of emissions. The health and wellbeing impacts varied and were often limited reflecting existing relatively high quality of life and environmental standards in most of the participating cities; the greatest potential for future health benefit occurs in less developed or developing countries. © 2016 Heaviside et al.