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Networked systems that gather sensor data in order to react to phenomena in their surroundings are faced with a growing need for adaptive behavior to operate in dynamically changing environments. In designing a networked system the data processing chain can be decomposed into functional components. These functional components interact by requesting information they need and fulfilling requests received from other components. Local evaluation of the available data with respect to the different requests and available resources is a key process in each component. An improved evaluation method is presented which is capable of locally balancing the information value against the resource costs of data. The experiments show that the evaluation method with the same amount of communication costs, results in a higher common picture quality with multiple objects and overlapping detection ranges.

This paper discusses the methods used in a study on the values of time and reliability in freight transport in the Netherlands. SP surveys were carried out among more than 800 shippers and carriers. A novel feature is that both for the value of time and reliability two additive components are distinguished: a transport cost and a cargo component. Specific instructions were given to make sure that the carriers provide the former and shippers that contract out the latter component. The resulting values that will be used in CBA in The Netherlands are presented and compared against the international literature. © 2014 Elsevier Ltd.

In thermal processes with highly inhomogeneous fuels it is desirable to know real time fuel characteristics. In the case of municipal solid waste combustion (MSWC) it was up till now not possible to determine the calorific value of the waste on-line with a high accuracy. In this paper, a new method is presented where the calorific value is determined by means of an observer. A model based upon the mass balance is used together with concentration measurements in the flue gas to calculate on-line the calorific value of the waste. The background of this observer based sensor is discussed in detail, including a sensitivity analysis. Results from tests in different full-scale MSWC plants are presented as well as a comparison with other known off-line methods. It will be shown that the sensor works well and is more accurate than the present off-line methods. Furthermore, some applications of the calorific value sensor will be shortly discussed. © 2004 Elsevier Ltd. All rights reserved.

The exploitation of subsurface hydrocarbon reservoirs is achieved through the control of production and injection wells (i.e., by prescribing time-varying pressures and flow rates) to create conditions that make the hydrocarbons trapped in the pores of the rock formation flow to the surface. The design of production strategies to exploit these reservoirs in the most efficient way requires an optimization framework that reflects the nature of the operational decisions and geological uncertainties involved. This paper introduces a new approach for production optimization in the context of closed-loop reservoir management (CLRM) by considering the impact of future measurements within the optimization framework. CLRM enables instrumented oil fields to be operated more efficiently through the systematic use of life-cycle production optimization and computer-assisted history matching. Recently, we have proposed a methodology to assess the value of information (VOI) of measurements in such a CLRM approach a-priori, i.e. during the field development planning phase, to improve the planned history matching component of CLRM. The reasoning behind the a-priori VOI analysis unveils an opportunity to also improve our approach to the production optimization problem by anticipating the fact that additional information (e.g., production measurements) will become available in the future. Here, we show how the more conventional optimization approach can be combined with VOI considerations to come up with a novel workflow, which we refer to as informed production optimization. We illustrate the concept with a simple water flooding problem in a two-dimensional five-spot reservoir and the results obtained confirm that this new approach can lead to significantly better decisions in some cases. © 2019, The Author(s).

This paper presents the results of an explorative research into value quantification methods called the Quick Scan. An overview of value quantification methods was needed in order to be able to establish the economically most advantageous tender, which in turn is needed for improvements in the Dutch construction sector. The Quick Scan project researched the literature, consulted experts and interviewed those involved in construction projects. Several value concepts and accompanying quantification methods have been found.

Agility is key for telecommunication operators to survive in a deregulated, competitive, and converging telecommunications environment. Openness and reusability have emerged as leading concepts to realize such agility. These concepts have both a business perspective and an operational perspective. Handling both perspectives in concert may provide competitive success. This article describes a strategy for managing commercial and operational agility in an open telecommunication value chain, using a structured approach for service orientation. © 2006 IEEE.

The building and construction industry has a large contribution and impact on society, e.g. economical and environmental, involving a vast spectrum of stakeholders. However, the value delivering performance of the industry has often been criticized. The predictability of the value, price and costs of built objects has proven to be difficult, particularly over the life cycle. The characteristics of construction, such as fragmented value chains, complex projects and long lead times are basic causes, often leading to cost and time overruns, delivery of less value than agreed, and dissatisfied clients and users. In addition, it is difficult to assess all uncertainties and risks beforehand. Besides, fixing the price and demands beforehand makes it difficult to respond to changing demands and circumstances, and to deploy increasing knowledge during the process. In this paper a value-price-cost (VPC) leverage model is presented for the dynamic and integrated control of value, price and costs through the life cycle of built objects, and the value chain, i.e. the cascade of value demanding parties (demand chain), and value supplying parties (supply chain). The model is based on a paradigm shift from a discrete process of fixed prices on fixed contract moments between different phases in the life cycle (static control), towards a continuous process of establishing and monitoring the VPC balance through the life cycle, and acting in case of changing demands or circumstances (dynamic control). The ultimate objective is to optimise the total benefit of the built object through the life cycle. The total benefit is defined as the sum of the profit for value supplying parties (contractors, suppliers, etc.), and the added value for value demanding parties (clients, users, etc.). The model implies the formation of a life cycle alliance around the built object, involving both value demanding and supplying parties keeping the VPC balance and acting when fluctuations in the value or costs of the built object occur during the operation phase. In addition, the alliance is responsible for safeguarding and maintaining the functionality and serviceability of the built object through the life cycle. To conclude, directions for the further development of the model are being discussed

Today STANAG 4569 is working towards a new volume of the AEP-55 including the Improvised Explosive Devices (IED) threat to vehicles and their occupants. Therefore, a follow-up of the HFM-090/TG-25 was required to establish common NATO test procedures and injury criteria for both the Anti-Vehicular (AV) mine and IED-threat, and the HFM-148/RTG was established. The goal of this group was to analyze injury loading mechanisms, investigate injury assessment criteria, define test methods and measurement tools to assess vehicles (and protection systems) against the mine and IED-threat. The combination of attack scenario and seat orientation yields the loading direction for the crew, which is relevant for the general loading mechanisms on the human body. The following body areas are considered the most important ones to be included in the injury assessment: head, neck, shoulder, thorax, abdomen, lumbar spine, upper and lower leg. The qualification of a vehicle depends on whether the responses for these body parts are below the pass/fail levels that are defined. Injury criteria were defined, and the pass/fail (tolerance) levels established for these body regions are considered to represent low risk of lifethreatening and disabling injuries. The criteria are associated with an Anthropomorphic Test Device (ATD) used for testing. The Hybrid III 50th percentile male is proposed for the loading scenarios where the IED is located underneath, in front or rear of the ATD. The EuroSid-2re 50th percentile male is proposed if the IED is located lateral of the ATD. Available injury criteria and ATDs lack validity for the blast loading conditions. Therefore additional research on the lower leg, the spine and the shoulder was performed. This research led to a more biofidelic surrogate leg (MIL-Lx) together with an injury risk curve to enable more accurate injury assessment for evaluating blast mitigation systems, materials, and structures. Also a new criterion for shoulder impact was developed and a new criterion for the spine is under development. All results are gathered and included in the test and injury assessment protocol which will be part of the STANAG 4569 AEP-55 volume 3. This paper gives an overview of all results, limitations and conclusions of the HFM-148/RTG work.

The steady state behaviour is analyzed of a periodically driven multi-DOF beam system which has an elastic stop at its middle. The elastic stop is modelled in a continuous way by using the contact law of Hertz. The beam is modelled by using finite elements and subsequently reduced by using a component mode synthesis method. The steady state behaviour of the system reduced to one, two and four DOF's is investigated by calculating periodic solutions at varying excitation frequency. Periodic solutions are calculated by solving two-point boundary value problems by the multiple shooting method in combination with a path-following technique. It is shown that models with more than one DOF are required for a good assessment of the long-term behaviour of the system. © 1996 Academic Press Limited.

This paper deals with the long term behavior of periodically excited mechanical systems consisting of linear components and local nonlinearities. The number of degrees of freedom of the linear components is reduced by applying a component mode synthesis technique. Lyapunov exponents are used to identify the character of the long term behavior of a nonlinear dynamic system, which may be periodic, quasi-periodic or chaotic. Periodic solutions are calculated efficiently by solving a two-point boundary value problem using finite differences. Floquet multipliers are calculated to determine the local stability of these solutions and to identify local bifurcation points. The methods presented are applied to a beam system supported by a one-sided linear spring, which reveals very rich, complex dynamic behavior.

The paper discusses the ideas behind an inception support modeller that uses state of the art Product Data Technology (PDT) and Knowledge Technology (KT). The modeller under development provides facility owners, facility owners to-be and project developers with the opportunity to create and evaluate a number of alternative solutions for their accommodation by stating their requirements such as functional requirements and resources such as available money and location. By applying knowledge rules, case mies and default values information gaps will be closed in order to generate more detailed alternatives. This process assures the availability of just enough product information to perform an evaluation of the performances and costs, and gives the facility owner a better view on a realistic solution for his requirements. Using a 3D front-end in combination with a requirements language which is easy to comprehend, the client can put in his requirements on different aspects of the project, like (cash flow, type of contract), building environment related aspects (availability of public transport or green), functional related aspects and components related aspects. Feedback will be given like cost evaluations, construction time and performance values expressed in money for energy usage, durability, maintainability, walking distances and such. The working of the tool is illustrated by a case, a Hospital Inception Modeller. The case evaluates the feasibility of the renovation of a Hospital Complex in Delft in The Netherlands

For the establishment of reference doses in mammography it is important to apply a dosimetric model relevant for risk assessment. Differences in dosimetric methods applied in mammography are related to the dosemeters used, e.g. thermoluminescent detectors and ionisation chambers, and the dosimetric quantities determined, i.e. entrance surface air kerma, entrance surface dose or average glandular dose. The exposure parameters influencing absorbed dose due to mammography include the X ray tube assembly, i.e. anode material, filtration and tube voltage; the exposure conditions, e.g. antiscatter grid, automatic exposure control and magnification; and characteristics of the film-screen combination including film processing and film density. The female breasts examined can be represented, on average, by a phantom or by a representative sample of patients. Reference values established in various protocols for entrance surface air kerma, entrance surface dose and average glandular dose are presented and discussed.

Digital government is often seen as an enabler or even driver of transformation of public administration, with the objective of creating public value. Such transformations are complex, requiring a long process of change; often, digitalization of public services is seen as the main means to this end. We investigate how digitalization of public services can be related to public sector transformation, and how this development can be linked to public value. In order to do so, this paper first conceptualizes digital government enabled transformation based on literature. Thereafter, we present an empirical example of public e-service development in Sweden. This case illustrates how e-service development can highlight shifts in societal values, and challenges that follow when trying to sustain changing societal values. Our findings suggest that in order to sustain transformation and (changing) public value, multiple processes of change and redesign need to be in place, not only of the organisational processes involved, but also of regulatory and institutional aspects, such as changes to the law and in the discretion and work practice of public officials. © 2018 is held by the owner/author(s). 4TU. Center for Research Data; Digital Government Society; Emerald Publishing; IOS Press

This paper deals with the long term behaviour of flexible rotor systems, which are supported by nonlinear bearings. A system consisting of a rotor and a shaft which is supported by one oil journal bearing is investigated numerically. The shaft is modelled using finite elements and reduced using a component mode synthesis method. The bearings are modelled using the finite-length bearing theory. Branches of periodic solutions are calculated for three models of the system with an unbalance at the rotor. Also self-excited oscillations are calculated for the three models if no mass unbalance is present. The results show that a mass unbalance can stabilize rotor oscillations. © 1996 Kluwer Academic Publishers.

It has been suggested that the transition towards a more circular economy requires multiple value creation, bui classical R&D management tools are not developed for easy assessment of circular economy innovations. We have developed a framework to support R&D in the assessment of such innovations on three levels of implementation (project production chain and society) and on three levels of detail (quick scan, brief assessment and thorough assessment) On the project level. capacity building is analyseti; on the production chain level. 'circular' performance is measured, on the societal level. the sustainability of the product is evaluated. The framework is being applied to wood products for the construction sector. Waste wood in the Netherlands is currently often incinerated with energy recovery. bat in consultation with stakeholders we are considering several potentially more valuable alternatives. With this case study, the developed framework is showing potential to steer R&D decisions in support of a more circular economy

Doel. Evaluatie van de Nederlandse screening op congenitale hypothyreoïdie (CHT). Opzet. Descriptief. Plaats. Landelijk. Methoden. Gegevens over de screening in de periode 1 januari 1981-31 december 1990 werden verkregen van de entadministraties, van laboratoria en van kinderartsen naar wie kinderen met afwijkende uitslagen verwezen werden. Resultaten. Van alle levendgeborenen werden 1.797.719 (99,5) kinderen gescreend op congenitale hypothyreoïdie (CHT). Er kwamen 10.165 kinderen (0,57 van alle gescreenden) voor verwijzing in aanmerking. Van de verwezen kinderen hadden 529 primaire CHT en 53 congenitaal thyreotropinedeficiëntiesyndroom (CTDS). De prevalentie van primaire CHT en CTDS was respectievelijk 1:3400 en 1:25.000. De sensitiviteit van het programma ten aanzien van primaire CHT was 99 en ten aanzien van CTDS 74. De specificiteit en de voorspellende waarde ten aanzien van alle vormen van CHT waren respectievelijk 99 en 6. Een van de doelen van het screeningsprogramma is bij alle patiënten de behandeling te beginnen voor de leeftijd van 22 dagen. Vóór screening was het cumulatieve percentage patiënten dat op de 21e dag reeds werd behandeld 6, na introductie van de screening was dat 54. Gescreende patiënten met een ernstige vorm van CHT werden in 72 van de gevallen behandeld voor dag 22. Conclusie. De screening levert een belangrijke bijdrage aan een vroegtijdige en effectieve opsporing van CHT-patiënten. Maatregelen om het aantal fout-positieve uitslagen te beperken zijn inmiddels genomen of zijn nog in onderzoek. Hoewel patiënten dankzij de screening veel eerder worden behandeld dan voor de screening, valt hier nog een aanzienlijke winst te boeken. Alleen door een gezamenlijke inspanning van de uitvoerders van de hielprik, de laboratoria, de entadministraties, huisartsen en kinderartsen kan dit bereikt worden. Chemicals/CAS: Thyrotropin, 9002-71-5.

This paper deals with two aspects concerning the optimization of municipal solid waste combustion (MSWC) processes. First of all, an on-line calorific value sensor is discussed by means of which the calorific value of the waste can be estimated from actual process data. Experimental results on a MSWC process are discussed which show that the sensor performs well. By means of a proper integration in the control system of an MSW combustion process a significant improvement of the control performance is expected. The second aspect is the validation of dynamic first-principles models in general and of a dynamic first-principles model of the MSW combustion process in particular on the basis of actual process data. A validated model is a powerful tool for optimization of the process operation performance. A validated dynamic model is particularly useful for the optimization of the control system of a process. A validation method is proposed using so-called system identification techniques. The proposed method was found to be a powerful tool for the validation of the MSWC first-principles model. This model was used to develop and test a new control concept for the MSWC process. It is shown that the control performance of a MSWC process can be improved significantly by this new control concept.

Accurate methods for the determination of vitamins in food are required for nutritional labelling, and for the production of food composition data for nutritional research on relationships between diet and health. The Standards, Measurement and Testing Programme of the European Commission is supporting a collaborative project involving 48 laboratories to improve their measurement in food. The research programme involves the use of method intercomparison studies to identify and control systematic errors, optimization of sample extraction and clean-up procedures, and the preparation of suitable food reference materials (RMs). Results are presented for the determination of vitamin D3 by HPLC and folates by microbiological assay in various foods demonstrating improved agreement between laboratories and possible reasons for improvements. In addition, examples of the food RMs produced and their potential use are described.

Objective. Evaluation of the Dutch national screening programme for phenylketonuria (PKU). Design. Descriptive. Setting. Nationwide. Methods. Data on the screening were obtained from the laboratories, from the registration offices of vaccination and screening results and from the paediatricians to whom infants with positive screening values were referred, during the period from September 1st, 1974 to December 31th, 1993. Results. During the study period 3,481,738 infants were screened in the Netherlands (99.4% of all births). The sensitivity of the programme was 98%, the specificity 99.99% and the positive predictive value 50%. The prevalence of PKU varied considerably between regions, e.g. from 1:33,600 in Zuid-Holland to 1:8,250 in Limburg (average in the Netherlands 1:18,000). The percentage of patients treated before the age of 22 days was 84% in the period from 1974 to 1988 and 95% in the period from 1989 to 1993 (p = 0.04). Birth weight in patients with PKU was 141 g (95% confidence interval: 66-216) less than the expected birth weight in the Netherlands. Furthermore, a slight growth retardation occurred in the first three years of life in early treated patients. The percentage of patients following special education was twice as high as in the general population (p < 0.001). Conclusion. The screening procedure for PKU is functioning at a high level. Despite early treatment development of patients with PKU is slightly below normal.