New Starch Derivatives for the Coating Industry

Continuous enzyme conversion in a jet cooker offers a lot of benefits compared to batch conversion. The starch has improved binding properties and a better overall performance. Gelpermeation chromatography shows a more favourable molecular weight distribution for the continuous enzyme converted starch. Wheat starch is a valuable binder in paper coating compared to maize starch and potato starch, when the conversion happens in the right way; continuous jet cooking gives the best results. Modified starches, such as Mylbond AC, an esterified starch, are very suitable as cobinder in topcoat applications. They show excellent binding properties and react faster with insolubilizers than oxidized enzyme converted starch, as shown by DSC measurements.     

The Benefits of Cationic Starches for the Paper Industry

Cationic starches are widely used as wet end additives in paper making. They provide many benefits, classified into 4 categories: improvement of mechanical strength; better retention of fines and fillers; faster drainage; reduction of waste water pollution. According to the accepted theory, a 2-part electrical layer is formed at the solid liquid interface. The zeta potential (existing at the interface between the 2 layers) is one important parameter which influences the retention of most ionic wet-end chemicals and governs many of the processes involved in making a functional paper product. Practical experiences showed us how to influence the zeta potential in order to obtain the desired benefits. The parameters depending on starch, which have been examined, are: the type of starch (origin), the level of addition and where it is used in the paper making process. Other influences come from the alum content, pH, occurance of shear forces and the presence of dissolved anionic material. Comparative laboratory tests have led to a better understanding of the rather complex interactions on which cationic activity is based. In this paper also the application of cationic starch in surface sizing compared to other starch modifications is discussed. Some important advantages, such as lower waste water pollution and better mechanical strength for the same pick-up, are claimed.     

A Scalable Architecture for MPEG-4 Wavelet Quantization

Wavelet-based image compression has been adopted in MPEG-4 for visual texture coding. All wavelet quantization schemes in MPEG-4—Single Quantization (SQ), Multiple Quantization (MQ) and Bi-level Quantization—use Embedded Zero Tree (EZT) coding followed by an adaptive arithmetic coder for the compression and quantization of a wavelet image. This paper presents the OZONE chip, a dedicated hardware coprocessor for EZT and arithmetic coding. Realized in a 0.5 m CMOS technology and operating at 32 MHz, the EZT coder is capable of processing up to 25.6 Mega pixel-bitplanes per second. This is equivalent to the lossless compression of 31.6 8-bit grayscale CIF images (352 × 288) per second. The adaptive arithmetic coder processes up to 10 Mbit per second. The combination of the performance of the EZT coder and the arithmetic coder allows the OZONE to perform visual-lossless compression of more than 30 CIF images per second. Due to its novel and scalable architecture, parallel operation of multiple OZONEs is supported. The OZONE functionality is demonstrated on a PC-based compression system.     

Power and Speed-Efficient Code Transformation of Video Compression Algorithms for RISC Processors

Upcoming multi-media compression applications will require high memory bandwidth. In this paper, we estimate that a software reference implementation of an MPEG-4 video decoder typically requires 200 Mtransfers/s to memory to decode 1 CIF (352×288) Video Object Plane (VOP) at 30 frames/s. This imposes a high penalty in terms of power but also performance.However, we also show that we can heavily improve on the memory transfers, without sacrificing speed (even gaining about 10% on cache misses and cycles for a DEC Alpha), by aggressive code transformations. For this purpose, we have manually applied an extended version of our data transfer and storage exploration (DTSE) methodology, which was originally developed for custom hardware implementations.     

Starch as Stilt Material in Carbonless Copy Paper - New Developments

For several reasons, calibrated wheat starch is by far the best performing stilt material in carbonless copy paper. Due to its size selection and its nice globular shape, it gives excellent stilt functionality at relatively low doses compared to native wheat starch. Less binder is needed and better copy quality obtained. It also has better runability properties than calibrated cellulose powder. For high speed running coating machines, involving a very intensive drying, a thermo-resistant calibrated wheat starch has been developed. This starch assures that also in the future, starch will stay the best performing stilt material for carbonless copy paper. Besides the classical advantages, such as better copy quality, the thermoresistant wheat starch offers some extra advantages, e. g. lower binder consumption.     

Random-access data storage components in customized architectures

This tutorial covers the basic design choices involved in customized data storage, including those for register files, local memory, caches, and main memory     

Iterative lumping approach for representing lipid feedstocks in fatty acid distillation simulation and optimization

The complexity of lipid feedstocks and the lack of data on physical properties hinder the simulation of oleochemical processing units. In this work, an iterative lumping approach is proposed to define an adequate number of key compounds such that diversification between lipid feedstocks becomes possible, while keeping the determination of physical properties as required for process modeling manageable. As a case study, the iterative lumping approach is used for simulation and optimization of a fatty acid distillation plant. For predicting vapor–liquid equilibria of fatty acids, the best results were acquired using the property method universal quasichemical-Hayden–O'Conell. Using the iterative lumping approach, 11 key compounds were selected to represent the feedstock. The process model properly predicts the product composition, yield, purity and heat duty. The most important process parameters are found to be side-reflux-ratio, reboiler-outlet-temperature, and heat-duty of the pitch-distiller. For optimization, an increase of the side-reflux-ratio and reboiler-outlet-temperature is recommended.