Non-TAG structuring of edible oils and emulsions

Mixtures of γ-oryzanol and β-sitosterol have been shown to structure pure edible oil phases. This paper reviews the phytosterol system, and compares it with other alternatives to structure edible oils. Furthermore, additional evidence based on small-angle X-ray scattering will be introduced to support the claim that structuring is based on fibril formation (diameter 7.2 nm). Finally, various aspects of the application of phytosterols structuring in water-in-oil emulsions were investigated.     

Enterprise Resource Planning in a large construction firm: implementation analysis

In most large Dutch construction firms, Enterprise Resource Planning (ERP) systems have replaced non‐integrated information systems with integrated and maintainable software. The implementation of ERP systems in such firms is a difficult task. So far, ERP implementations have yielded more failures than successes. This study tries to understand the factors that lead to the success or failure of ERP in large construction firms by focusing on the fits between the following pairs of elements in ERP implementations: business and IT strategy, maturity of the IT infrastructure and the strategic role of IT, and the implementation method and organizational change. The premise of this study is that for an ERP implementation to be successful these elements must somehow fit together. Empirical research was conducted through a case study of three ERP implementations in different business units of a Dutch‐based construction firm. Implementing different systems within one company is typical of the way large construction firms in the Netherlands have dealt with ERP. The study shows that the success of ERP implementations depends on consistent patterns between: IT strategy and business strategy, IT maturity and the strategic role of IT, and the implementation method and organizational change.     

Demonstration projects and sustainable housing

Because of the complicated structure of the built environment, it is frequently difficult to obtain good results on sustainable development projects. In The Netherlands, the Dutch government have used a range of new steering instruments which have cleverly enabled innovation to take place within a market economy. This imaginative governmental process uses covenants, network management and above all, demonstration projects to assess the feasibility of innovation. The authors describe the process and consider examples from energy efficient and sustainable housing, highlighting the importance of clear targets.     

Chinese Remaindering Based Cryptosystems in the Presence of Faults

We present some observations on public-key cryptosystems that use the Chinese remaindering algorithm. Our results imply that careless implementations of such systems could be vulnerable. Only one faulty signature, in some explained context, is enough to recover the secret key. Received 19 April 1997 and revised 11 February 1998     

Accelerated synthesis of all-silica DD3R and its performance in the separation of propylene/propane mixtures

Synthesis of the all-silica Deca-Dodecasil 3 Rhombohedral (DD3R) zeolite was accelerated 10 times by seeding with small amount of crystals (0.02 wt%) with yields approaching 100%. The effects of other synthesis variables, like silica source, the presence of methanol or the synthesis pH on the final product distribution have been studied. The adsorption and separation of propylene and propane mixtures on this material are presented. The improved synthesis may form the basis to scale-up production of DD3R for selective separation processes. The single component adsorption isotherms could be well described with a dual-site Langmuir model. The binary mixture adsorption was determined from breakthrough/desorption experiments at 323, 358 and 383 K. By modelling the adsorptive column, diffusion coefficients at infinite dilution for single component and the effect of propane over propylene adsorption were determined. Cylindrical geometry describes the pore topology of DDR type materials well. Propane decreases the uptake rate of propylene by adsorption in the surface of the crystals. Propylene diffusion is best described by the “strong confinement” model inside the zeolite cages. Separation is due to only propylene adsorption with diffusion as rate determining step.Results revealed DD3R as a very effective molecular sieve for the separation or purification of propane–propylene mixtures.     

Welfare distribution effect of a price reduction in the Dutch gas transport market: A scenario analysis of regulatory policy, market form and rent allocation

As part of the larger energy market deregulation program, the Dutch energy authority—DTe—has developed the habit to force the Dutch gas transport enterprise—Gas Transport Services, or GTS—to lower its prices. DTe's key argument is that lower gas transport prices will benefit the end-user. Indeed, that might well be the case. This policy, in general, is in line with European legislation on the liberalization of the gas market. We model and simulate the (domestic) welfare effects of a 5 percent transport price reduction. From this, we conclude that at least three observations complicate matters substantially. First, GTS is government-owned, and the dominant shipper—Gasunie Trade & Supply (or GasTerra, as it was recoined recently)—is partly so (50%). Second, shippers enter into the competitive game to make profits. Third, not only is the majority of gas transported in the Netherlands exported to foreign end-users, but also foreign owners have a large stake in Dutch shippers. As a result, part of the rents will always be distributed, or will ‘leak’ away, to foreign consumers and shippers (or their shareholders). These three observations together have three important implications. First, state ownership implies that much rent allocation is simply a matter of circulating money from one government sub-budget to the other. Second, given that the industry is imperfectly competitive, part of the rents will not be passed on to the end-consumers. Third, it is unavoidable that a substantial part of the rents are transferred abroad. A general conclusion for policy-makers is that market liberalization might not bring ex post what they expected ex ante.     

On automated analysis of flow patterns in cerebral aneurysms based on vortex identification

It is hypothesized that the risk of rupture of cerebral aneurysms is related to geometrical and mechanical properties of the arterial wall as well as to local hemodynamics. In order to gain better understanding of the hemodynamical factors involved in intra-aneurysmal flows, a thorough analysis of the 3D velocity field within an idealized geometry is needed. This includes the identification and quantification of features like vortices and stagnation regions. The aim of our research is to develop experimentally validated computational methods to analyse intra-aneurysmal vortex patterns and, eventually, define candidate hemodynamical parameters (e.g. vortex strength) that could be predictive for rupture risk. A computational model based on a standard Galerkin finite-element approximation and an Euler implicit time integration has been applied to compute the velocity field in an idealized aneurysm geometry and the results have been compared to Particle Image Velocimetry (PIV) measurements in an in vitro model. In order to analyze the vortices observed in the aneurysmal sac, the vortex identification scheme as proposed by Jeong and Hussain (JFM 285:69–94, 1995) is applied. The 3D intra-aneurysmal velocity fields reveal complex vortical structures. This study indicates that the computational method predicts well the vortex structure that is found in the in vitro model and that a 3D analysis method like the vortex identification as proposed is needed to fully understand and quantify the vortex dynamics of intra-aneurysmal flow. Furthermore, such an automated analysis method would allow the definition of parameters predictive for rupture in clinical practice.