Improved passive-matrix multiplexability with a modular display and UTCP technology

One of the major problems with PM displays is that, depending on the used display material, only a limited number of lines can be multiplexed. We developed a new driving technology and display setup that takes care of that problem. We divided the display into several independent parts or modules. Each module acts as an individual display and has its own display driver. With the use of the new ultra-thin chip package (UTCP), these driver chips can be embedded into the (flexible) display itself. This paper explains the setup of the fully modular display and describes the basic structure of the display drivers and its components.     

Peak loads and network investments in sustainable energy transitions

Current energy distribution networks are often not equipped for facilitating expected sustainable transitions. Major concerns for future electricity networks are the possibility of peak load increases and the expected growth of decentralized energy generation. In this article, we focus on peak load increases; the effects of possible future developments on peak loads are studied, together with the consequences for the network. The city of Eindhoven (the Netherlands) is used as reference city, for which a scenario is developed in which the assumed future developments adversely influence the maximum peak loads on the network. In this scenario, the total electricity peak load in Eindhoven is expected to increase from 198 MVA in 2009 to 591–633 MVA in 2040. The necessary investments for facilitating the expected increased peak loads are estimated at 305–375 million Euros. Based upon these projections, it is advocated that – contrary to current Dutch policy – choices regarding sustainable transitions should be made from the viewpoint of integral energy systems, evaluating economic implications of changes to generation, grid development, and consumption. Recently applied and finished policies on energy demand reduction showed to be effective; however, additional and connecting policies on energy generation and distribution should be considered on short term.     

Progress under bounded fairness

Summary. Progress is investigated for a shared-memory distributed system with a weak form of fault tolerance that allows processes to stop and restart functioning without notification. The concept of bounded fairness is introduced to formalize bounded delay under the assumption that each family of related processes continuously contains at least one active member. This is a generalization of wait-freedom, and also of a finitary form of weak fairness. Several useful proof rules are stated and proved. In a system with bounded fairness, a wait-free process can be constructed by forming a new process in which processes from the various families are scheduled in a round robin way. The theory is applied to prove progress within bounded delay for a linearizing concurrent data-object in shared memory. The safety properties of this algorithm have been treated elsewhere. Received: April 1998 / Accepted: March 1999     

Influence of DOC on the Inactivation Efficiency of Ozonation Assessed with Clostridium perfringens and a Lab-Scale Continuous Flow System

Routine quality monitoring for fecal indicators after ozonation at the river-lake waterworks Weesperkarspel of Amsterdam Water Supply (AWS) show large variation in inactivation. The influence of the high DOC in the water on the inactivation efficiency was investigated. Results showed a higher inactivation of Clostridium perfringens in the AWS water than in a water with low DOC at the same CT conditions. The contribution of the gas feed chamber to the overall inactivation of C. perfringens was high in the AWS water and was reduced after DOC reduction with GAC. This result may alter the current CT concept of the process. Further research will be focused on the ozone dosage strategy and control related to the required CT for inactivation and the production of by-products.     

Surface segregation in blends containing poly(dimethylsiloxane)-polystyrene block copolymers

The surface composition of polystyrene blends containing poly(dimethylsiloxane)-polystyrene block copolymers have been analyzed using X-ray photoelectron spectroscopy (XPS), contact angle measurements, and time-of-flight secondary ion mass spectrometry (TOFSIMS). The three techniques showed the surface of the blend samples to be identical to pure poly(dimethylsiloxane) homopolymer, despite the fact that the systems each contained only a 2% bulk concentration of siloxane. The high surface sensitivity of TOFSIMS—which probes the samples to depths of a few angstroms—indicates an enrichment of-Si(CH₃)₃ groups at the surface. These are the terminal groups of the PDMS part of the block. Their enrichment at the surface of the samples is presumably due to their low surface energy, in addition to the tendency for end groups to be at the surface due to free volume considerations.Presented at the XXVIth Silicon Symposium, Indiana University-Purdue University at Indianapolis, March 26–27, 1993.     

Exploration of the land potential for the production of biomass for energy in the Netherlands

The energy potential for energy crops and biomass residues in the Netherlands is assessed. The analysis explores the possible use of land for biomass production in the future. Various government memorandums and analyses of the expected future land use in various sectors have served as the basis for the assessment of the supply of and the demand for land in the future. In this study the potential supply of agricultural land is based on expected productivity increments in agriculture and assumptions with respect to the future demand for agricultural products. Various future claims for infrastructure, forestry, urban areas and nature are subtracted from the expected supply. The net projected supply of land ranges from zero to 52 000 ha in 2000 to 110 000-250 000 ha in 2015. The supply of agricultural land depends however on a number of supra-national factors, such as the European agricultural policy, world market developments and the agricultural production in the countries in Eastern Europe. Uncertainties remain, therefore, and the projected supply of agricultural land should be considered as a possible scenario based on current trends. If the calculated land potential is used for energy crops like miscanthus and short rotation coppice, this land could contribute 0-10 PJ in 2000 and 27-59 PJ in 2015. Secondary biomass yields, such as those from forestry, agricultural residues, wood from prunings, etc., could contribute a further 34 PJ in 2000, decreasing to approximately 28 PJ in 2015. Taken together these potentials could satisfy 1-1.5% of the energy requirements of the Netherlands in 2000 and 1.5-2.5% in 2015, provided that energy farming is an economically feasible activity for farmers.     

Effects of Groyne Layout on the Flow in Groyne Fields: Laboratory Experiments

This research is aimed at finding efficient alternative designs, in the physical, economical, and ecological sense, for the standard groynes as they are found in the large rivers of Europe. In order to test the effects of various groyne shapes on the flow in a groyne field, experiments were performed in a physical model of a schematized river reach, geometrically scaled 1:40. Four different types of schematized groynes were tested, all arranged in an array of five identical groyne fields, i.e., standard reference groynes, groynes with a head having a gentle slope and extending into the main channel, permeable groynes consisting of pile rows, and hybrid groynes consisting of a lowered impermeable groyne with a pile row on top. Flow velocities were measured using particle tracking velocimetry. The design of the experiment was such that the cross-sectional area blocked by the groyne was the same in all cases. Depending on the groyne head shape and the extent of submergence variations in the intensity of vortex shedding and recirculation in the groyne field were observed. The experimental data are used to understand the physical processes like vortex formation and detachment near the groyne head. It is demonstrated that the turbulence properties near and downstream of the groyne can be manipulated by changing the permeability and slope of the groyne head. It is also observed that for submerged conditions the flow becomes complex and locally dominated by three-dimensional effects, which will make it difficult to predict by applying depth average numerical models or by three-dimensional models with a coarse resolution in the vertical direction.     

Detection and Localization of Delaminations in Thin Carbon Fiber Reinforced Composites with the Ultrasonic Polar Scan

In this paper, the hybrid compliance-stiffness matrix method for simulating wave propagation in (delaminated) multilayered media with viscoelastic anisotropy has been confronted with high-quality amplitude and phase experiments on delaminated composites, obtained using the ultrasonic polar scan setup (UPS) in transmission by considering harmonic as well as pulsed ultrasound. Results are presented for multiple thin carbon/epoxy laminates with an artificial edge delamination induced by a foil insert, showing a good agreement between experimental recording and numerical modeling. The obtained results further reveal the feasibility of the harmonic UPS to detect and even locate the depth-position of multiple delaminations in fiber reinforced composites. Considering that the harmonic UPS method does not rely on the detection of different echoes like the classical C-scan, but rather expounds the conditions for efficient stimulation of guided waves in the solid, the method is found to be highly suited for inspecting thin composite materials for the presence of delaminations.     

Reduction‐Sensitive Dextran Nanogels Aimed for Intracellular Delivery of Antigens

Targeting of antigens to dendritic cells (DCs) to induce strong cellular immune response can be established by loading in a nano‐sized carrier and keeping the antigen associated with the particles until they are internalized by DCs. In the present study, a model antigen (ovalbumin, OVA) is immobilized in cationic dextran nanogels via disulfide bonds. These bonds are stable in the extracellular environment but are reduced in the cytosol of DCs due to the presence of glutathione. Reversible immobilization of OVA in the nanogels is demonstrated by the fact that hardly any release of the protein occurred at pH 7 in the absence of glutathione, whereas rapid release of OVA occurs once the nanogels are incubated in buffer with glutathione. Furthermore, these OVA conjugated nanogels show intracellular release of the antigen in DCs and boost the MHC class I antigen presentation, demonstrating the feasibility of this concept for the aimed intracellular antigen delivery.     

Technological learning in bioenergy systems

The main goal of this article is to determine whether cost reductions in different bioenergy systems can be quantified using the experience curve approach, and how specific issues (arising from the complexity of biomass energy systems) can be addressed. This is pursued by case studies on biofuelled combined heat and power (CHP) plants in Sweden, global development of fluidized bed boilers and Danish biogas plants. As secondary goal, the aim is to identify learning mechanisms behind technology development and cost reduction for the biomass energy systems investigated. The case studies reveal large difficulties to devise empirical experience curves for investment costs of biomass-fuelled power plants. To some extent, this is due to lack of (detailed) data. The main reason, however, are varying plant costs due to differences in scale, fuel type, plant layout, region etc. For fluidized bed boiler plants built on a global level, progress ratios (PRs) for the price of entire plants lies approximately between 90–93% (which is typical for large plant-like technologies). The costs for the boiler section alone was found to decline much faster. The experience curve approach delivers better results, when the production costs of the final energy carrier are analyzed. Electricity from biofuelled CHP-plants yields PRs of 91–92%, i.e. an 8–9% reduction of electricity production costs with each cumulative doubling of electricity production. The experience curve for biogas production displays a PR of 85% from 1984 to the beginning of 1990, and then levels to approximately 100% until 2002. For technologies developed on a local level (e.g. biogas plants), learning-by-using and learning-by-interacting are important learning mechanism, while for CHP plants utilizing fluidized bed boilers, upscaling is probably one of the main mechanisms behind cost reductions.