Quality Control for Scalable Media Processing Applications

Many media processing applications create a load that varies significantly over time. Hence, if such an application is assigned a lower processing-time budget than needed in its worst-case load situation, deadline misses are likely to occur. This problem can be dealt with by designing media processing applications in a scalable fashion. A scalable media processing application can run in multiple qualities, leading to correspondingly different resource demands. The problem we consider is to find an accompanying quality control strategy, which minimizes both the number of deadline misses and the number of quality changes, while maximizing the quality of processing. We present an initial approach to the above problem by modeling it as a Markov decision process (MDP). Our model is based on measuring relative progress at milestones. Solving the MDP results in a quality control strategy that can be applied during runtime with only little overhead. We evaluate our approach by means of a practical example, which concerns a scalable MPEG-2 decoder.     

Understanding TES microcalorimeter noise and energy resolution

We have performed numerical calculations of the noise in voltage-biased superconducting transition edge-based X-ray microcalorimeters, using a finite-element model. Details of the model are discussed, as well as results for different absorber geometries. The results are in agreement with an analytical model and show that the amount of internal thermal fluctuation noise can be reduced by using a segmented absorber. The simulation also agrees well with experimental data, which, for our detectors, contain no major unidentified noise sources. Furthermore, the discrepancy between the (small-signal) theoretical and the measured energy resolutions for 5.9 keV X-rays, for our sensors typically a factor of 2, is explained by a more accurate modelling of the sensor responsivity, taking into account the large signal behaviour.     

Corroles as receptors in liquid membrane electrodes and their potentiometric response towards salicylic acid

Here, we report on the application of corroles as analytically active compounds in liquid membrane electrodes (ISE) that are sensitive towards salicylic acid and salicylate.The potentiometric signals generated by corrole-incorporated ISEs strongly depend on the pH of the aqueous sample solution and the membrane composition, such as the presence of lipophilic sites. Corrole incorporating ISEs are characterised by a low detection limit (4.0 × 10⁻⁵ M) and a wide linear range (4.0 × 10⁻⁵ to 5.3 × 10⁻³ M). Also, they are free from interference versus other organic anions.The mechanism of the generation of the potentiometric signals of corrole incorporating ISEs in the presence of salicylate anion, as well salicylic acid, will be discussed.     

Consumption of foods and micronutrients and the risk of cancer of the biliary tract

BACKGROUND: Gallstones and obesity have been suggested as risk factors for cancer of the biliary tract. Since both factors are related to diet, we studied the relationship between dietary intake and the cancer of interest in a population-based case-control study. METHODS: The study population comprised 111 patients and 480 controls. Food intake was assessed by means of a semiquantitative food frequency questionnaire. Estimates of the intake of foods and micronutrients were obtained from cases and controls themselves (direct respondents) or from relatives (indirect respondents). Participants were categorized into tertiles of intake. Risk ratios were estimated by logistic regression analysis. RESULTS: The major findings are a monotonic decrease in risk associated with the consumption of vegetables (ORs 1.0, 0.7, 0.4, P value trend < 0.01) and a monotonic increase in risk associated with sugar added to drinks and desserts (ORs 1.0, 1.3, 2.5; P value trend < 0.01). CONCLUSIONS: The finding on added sugar corresponds to our earlier report that the group monosaccharides and disaccharides is a potential risk factor for this cancer. Sugar may influence bile composition through lipoprotein metabolism. The protective effect of vegetables is in accordance with the reported inverse relationship between vegetables and many epithelial cancers of the alimentary tract.     

Uncertainty Matters: Computer Models at the Science–Policy Interface

The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However, despite the advantages modelling presents, the integration of information derived from models into policy is far away from being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying out management plans at regional and national scale. We suggest that the solution to integrate modelling information into policy formulation lies on both the modelling and the policy-making communities.     

Congenital pulmonary lymphangiectasis with chylothorax: a heterogeneous lymphatic vessel abnormality

We describe the generation of a new antipeptide antibody that binds to the centromeric region of human mitotic chromosomes. This antibody was raised against a synthetic peptide corresponding to the 481-493 amino acid sequence of the human CENP-B autoantigen. Immunofluorescence analysis revealed that this anti-CENP-B serum showed an identical pattern to the human CREST anticentromere autoantibody in both mitotic cells and interphase nuclei. Immunoblotting showed that this antibody reacts with the recombinant human CENP-B autoantigen, indicating that it is directed to the 80-kDa centromere polypeptide. We have used this serum to determine, by indirect immunofluorescence, whether CENP-B is conserved in different mammalian species. Surprisingly, the human antipeptide antibody does not react with the centromeric proteins of cultured mouse, hamster, or Indian muntjac cells. Because the CENP-B gene has been cloned in human and mouse, our results suggest that the CENP-B epitope used as an immunogen in this study is not ubiquitous in mammalian cells, and that we have most probably established a monospecific antibody to the human centromere.     

A 4/7 kHz audio bandwidth selectable digital phone interface (DPI)chip with on-chip analog functions and modem

The Digital Phone Interface (DPI) is designed for a new generation of digital telephone terminals for private exchanges, This circuit gives a total solution for all telephone functions, thereby including DSP functions, voice coding/decoding and analog front end, signal generators for DTMF and ringing, a modem for data transfer between terminal and exchange and a multitude of interfaces to communicate to the external world. Besides the normal earpiece micro and speaker, handsfree operation is available by using a selectable input low-noise microphone amplifier and an additional 50 Ω mWLS driver. For the handsfree operation, a digital AGC and anti-oscillation (anti-larsen) function is implemented. The line modem generates a modified RTZ (WAL2) code and is able to cover distances up to 1.5 km. In addition, the component is extensible with external signal processing modules (echo cancelling) and is also able to transfer a 7 kHz speech bandwidth. The device is a mixed analog/digital design produced in a 1.2 μm CMOS technology on 46 mm ² die area and consumes 200 mW     

A criterion for atomicity revisited

Concurrent and reactive programs are specified by their behaviours in the presence of a nondeterministic environment. In a natural way, this gives a specification (ARW) of an atomic variable in the style of Abadi and Lamport. Several implementations of atomic variables by lower level primitives are known. A few years ago, we formulated a criterion to prove the correctness of such implementations. The proof of correctness of the criterion itself was based on Lynch’s definition of atomicity by serialization points. Here, this criterion is reformulated as a specification HRW in the formal sense. Simulations from HRW to ARW and vice versa are constructed. These now serve as a constructive proof of correctness of the criterion. Eternity variables are used in the simulation from HRW to ARW. We propose so-called gliding simulations to deal with the problems that appear when occasionally the concrete implementation needs fewer steps than the abstract specification.