The contribution of control systems in LWR safety

The objective of this paper is to estimate the effects of non-safety-grade control systems in light water reactors (LWRs) on the overall likelihood of accidents leading to severe core damage or core melt, as determined from operating experience. One hundred ninety operational events which involve failures of non-safety-grade control systems that have occurred at commercial PWR plants during 1969–1981 and which are considered to be precursors to potential severe core damage have been identified; eighty such events have been identified for BWR plants. These events are treated as initiating or concurrent events to be fit into appropriate event trees, which are then quantified using component failure rates and system unavailabilities taken from available PRA studies to estimate the frequency of severe core damage arising from non-safety-grade control system failures. An example is worked out in detail. Considerable uncertainty is introduced into the results by the choice of system and operator failure rates and the results reported herein are considered preliminary. No allowance is made in these estimates for plant changes made because of operational experience.     

Comparison of the physico‐chemical characteristics of a new triploid banana hybrid,FLHORBAN 920, and the Cavendish variety

BACKGROUND: The physico‐chemical characteristics of a new banana triploid hybrid (FLHORBAN 920 cultivar, AAA group), partially resistant to Yellow Sigatoka and Black Leaf Streak diseases, were measured throughout ripening and compared with those of the Cavendish banana. RESULTS: The greatest differences between FLHORBAN 920 (F920) and the Cavendish variety were observed at intermediate maturity, when bananas were yellow with green tips or yellow. The F920 bananas have more dry matter and starch than those of Cavendish. The total polyphenol contents of F920 bananas were three‐fold higher than Cavendish. The sucrose contents were 1.5‐fold higher in F920 fruits, whereas glucose and fructose contents were two‐fold higher in Cavendish fruits. The F920 fruits had fewer esters, carbonyls and phenolic ethers than Cavendish. The two varieties differed in the composition in methyl‐branched (alcohols and esters) and phenolic ether volatile compounds. CONCLUSION: These characteristics, coupled with resistance to the principal banana diseases, suggest that the F920 variety should be developed further. Copyright © 2008 Society of Chemical Industry     

Adapted Total Variation for Artifact Free Decompression of JPEG Images

The widely used JPEG lossy baseline coding system is known to produce, at low bit rates, blocking effects and Gibbs phenomenon. This paper develops a method to get rid of these artifacts without smoothing images and without removing perceptual features. This results in better looking pictures and improved PSNR. Our algorithm is based on an adapted total variation minimization approach constrained by the knowledge of the input intervals the unquantized cosine coefficients belong to. In this way, we reconstruct an image having the same quantized coefficients than the original one, but which is minimal in term of the total variation. This discourages blocking effects and Gibbs phenomenon to appear while edges are kept as sharp as possible. Although the proposed subgradient method is converging in infinite time, experiments show that best results are obtained with a very few number of iterations. This leads to a simple and fast algorithm that may be applied to the great set of JPEG images to decompress them more efficiently.This work was also supported in part by CNES, 18 avenue E. Belin, 31055 Toulouse Cedex, France and Science Pratique SA, 47 avenue Carnot, 94230 Cachan, France under Grant 762/00/CNES/8319; by CMLA, ENS Cachan, 61 avenue du Président Wilson, 94235 Cachan Cedex, France; by DOLabs, 3 rue Nationale, 92100 Boulogne-Billancourt, France and by MAP5, UFR mathématiques et informatique, Université Paris 5, 45 rue des Saints Pères, 75270 Paris Cedex 06, France. François Alter was at École Normale Supérieure Ulm in Paris from 1998 to 2003, and entered the Corps des Mines attached to the French minister in charge of industry in 2003. He received M.Sc. degree in Pure Mathematics from Paris 6 University in 2001. Since 2002, he has been preparing his Ph.D. in Image Processing and Analysis at CMLA in Cachan, France. His research interests are Geometric Partial Differential Equations and Stochastic Perception Theory. Sylvain Durand received his PhD in applied mathematics, in 1993, from Paris-Dauphine University, France. In 1994 and 1995, he held a postdoctoral position at Washington University of St. Louis, Missouri. He is currently assistant professor at Jules Verne University of Picardie, France. His research interests include mathematical aspects of image processing. Jacques Froment received the Ph.D. degree in applied mathematics from Paris-Dauphine University, France, in 1990. During the academic year 1990/1991, he was an associate research scientist at the Courant Institute of Mathematical Sciences in NYUs computer science department. From 1991 to 2002, he was an assistant professor in the department of mathematics at Paris 5 University, France. He is currently professor of applied mathematics at the University of Bretagne Sud, Vannes, France. His research interests include mathematical models in computer vision and representation of meaningful information with applications to image compression and restoration.This revised version was published online in June 2005 with correction to CoverDate     

Altering the association properties of insulin by amino acid replacement

The importance of ProB28 and LysB29 on the self-association of insulin was established by systematically truncating the C terminus of the B chain. The relationship between structure and association was further explored by making numerous amino acid replacements at B28 and B29. Association was studied by circular dichroism, size-exclusion chromatography and ultracentrifugation. Our results show that the location of a prolyl residue at B28 is critical for high-affinity self-association. Removal of ProB28 in a series of C-terminal truncated insulins, or amino acid replacement of ProB28, greatly reduced association. The largest disruption to association was achieved by replacing LysB29 with Pro and varying the amino acid at B28. Several of the analogs were predominantly monomers in solutions up to 3 mg/ml. These amino acid substitutions decreased association by primarily disrupting the formation of dimers. Such amino acid substitutions also substantially reduced the Zn-induced insulin hexamer formation. The formation of monomeric insulins through amino acid replacements was accompanied by conformational changes that may be the cause for decreased association. It is demonstrated that self-association of insulin can be drastically altered by substitution of one or two key amino acids.     

Application of the Critical Surface Tension Concept to Items in Our Everyday Life

One form of tribute to a scientist is the utilization of his work to advance technology. This review is to cite the application of Zisman's work to what are perhaps some unusual, or at least unfamiliar, technologies-dental restoratives, hair treatment, shaving and the processing of wastes. I have singled out these few because of personal involvement and recognition of the large contribution of Zisman and co-workers in their advancement and understanding. This, then, is a narrow and personal review of the scientific contributions of William A. Zisman.     

The concept of ‘IT artifact’ has outlived its usefulness and should be retired now

Vastly inconsistent definitions of the term “the IT artifact” in leading journals and conferences demonstrate why it no longer means anything in particular and should be retired from the active IS lexicon. Examples from the literature show why artifact‐cousins, such as the IS artifact, sociotechnical artifact, social artifact, and ensemble artifact should be used with great care, if not retired as well. Any void created by these retirements could be filled through the following approaches: (i) relabeling with simple terms that are immediately understandable; (ii) adopting guidelines for making sense of the whole X‐artifact family; and (iii) sidestepping the IT artifact and focusing directly on IT‐enabled work systems in organizations.     

Heat stress adaptation induces cross-protection against lethal acid stress conditions in Arcobacter butzleri but not in Campylobacter jejuni

The ability of many bacteria to adapt to stressful conditions may later protect them against the same type of stress (specific adaptive response) or different types of stresses (multiple adaptive response, also termed cross-protection). Arcobacter butzleri and Campylobacter jejuni are close phylogenetic relatives that occur in many foods of animal origin and have been linked with human illness (mainly diarrhoea). In the present study, sublethal stress adaptation temperatures (48 °C and 10 °C) and mild and lethal acid conditions (pH 5.0 and pH 4.0) were determined for A. butzleri and C. jejuni. In addition, it was evaluated whether these sublethal stress adaptations cause specific adaptive responses or cross-protection against subsequent mild or lethal acid stresses in these bacteria. The studies were conducted in broth adjusted to the different conditions and the results were determined by the dilution series plating method. It was shown that heat stress adapted A. butzleri (incubated for 2 h at 48 °C) were significantly more resistant to subsequent lethal acid stress (pH 4.0) than non-adapted cells at the 1 h time-point (p < 0.01 in Wilcoxon rank sum test). No specific adaptive responses against the stresses in A. butzleri or C. jejuni and no cross-protection in C. jejuni were found. The ability of heat stressed A. butzleri to tolerate later lethal acid conditions should be taken into account when designing new food decontamination and processing strategies.     

Uncertainty Propagation in Model-Based Recognition

Robust recognition systems require a careful understanding of the effects of error in sensed features. In model-based recognition, matches between model features and sensed image features typically are used to compute a model pose and then project the unmatched model features into the image. The error in the image features results in uncertainty in the projected model features. We first show how error propagates when poses are based on three pairs of 3D model and 2D image points. In particular, we show how to simply and efficiently compute the distributed region in the image where an unmatched model point might appear, for both Gaussian and bounded error in the detection of image points, and for both scaled-orthographic and perspective projection models. Next, we provide geometric and experimental analyses to indicate when this linear approximation will succeed and when it will fail. Then, based on the linear approximation, we show how we can utilize Linear Programming to compute bounded propagated error regions for any number of initial matches. Finally, we use these results to extend, from two-dimensional to three-dimensional objects, robust implementations of alignment, interpretation-tree search, and transformation clustering.     

Synthesis and characterization of a novel highly phosphonated water-insoluble polymer

A novel polymer, functionalized by tetrafluoroaryl phosphonic acid units, was prepared by free-radical polymerization of the corresponding styrene monomer. The obtained polymer was analyzed by gel permeation chromatography, differential scanning calorimetry, and spectroscopy (NMR, IR). Ion exchange capacity of the water-insoluble polymer was determined in methanol solution by titration with 0.1M NaOH. The proton conductivity of the polymer of 9.91 × 10⁻⁷ S cm⁻¹ as disclosed by electrochemical impedance spectroscopy renders this polymer a promising candidate for solid electrolyte applications or as a water-insoluble dopant for proton exchange membrane applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48235.