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121.
In the context of an industrial project, we evaluated the implementation of the software of a casino slot machine. This software has a significant amount of crosscutting concerns that depend on and interact with each other as well as with the modular concerns. We therefore wished to express our design using an appropriate aspect-oriented modeling approach. We therefore evaluated three candidate methodologies: Theme/UML, WEAVR, and RAM to establish their suitability. Remarkably, only the last of the three has shown to allow an adequate expression of the interactions, albeit not fully explicit. The first two fall short because half of the interaction types cannot be expressed at all while the other half need to be expressed using a work-around that hides the intention of the design. Neither does RAM allow a fully explicit expression of interactions, but it would be the most adequate approach for the slot machine case. 相似文献
122.
Scanning electron microscope evaluation could be criticized if the method adopted to correct for bias is not specified in the study design. Observers can draw conclusions from images unconsciously chosen to best support their research hypotheses, impairing the basic research principle of operator's impartiality. In this study, a systematic observation method has been described and verified for repeatability. The number and the observation points on a certain specimen have been predetermined using a scheme along with observation rules previously established in the research protocol. When our instrument is used at an operating magnification between 500× and 1,000× (corresponding to a frame of 250×190 µ and 120×90 µ, respectively), the method allowed 100% repeatable observation frames, with linear frame errors in finding an observation point of 12.5% in length and 16.8% in height. With modifications to accommodate research objective and statistical requirements, the method could be applied to many SEM observation study. SCANNING 32: 97–103, 2010. © 2010 Wiley Periodicals, Inc. 相似文献
123.
The development of a high throughput reactor for the catalytic screening of three phase reactions 总被引:1,自引:0,他引:1
Stuart Thomson Christian Hoffmann Silvia Ruthe H. -W. Schmidt Ferdi Schüth 《Applied Catalysis A: General》2001,220(1-2):253-264
The design and utilisation of a reactor for the optimisation of multiple heterogeneous catalytic reactions in liquid phase is described. With the ability to screen up to 25 samples simultaneously at a maximum pressure of 50 bar, the reactor is one of the first to be designed specifically for what is termed stage II, the optimisation phase, of catalytic high throughput experimentation (HTE). Experiments demonstrating the reliability and reproducibility of the reactor are described, including the use of the reactor to study the catalytic hydrogenation of crotonaldehyde (CrAld) over bimetallic samples based on a commercial 5 wt.% Pt on activated carbon catalyst. Modification of the mono-metallic Pt sample by the impregnation of aqueous metal salts and various pre-treatments, resulted in 140 bimetallic catalysts that were used in the hydrogenation study. The changes observed in both selectivity and reactivity of the modified catalysts are described and show, by way of example, how the speed of catalyst screening can be increased by at least an order of magnitude. 相似文献
124.
Paolo Bertoldi Silvia Rezessy Eoin Lees Paul Baudry Alexandre Jeandel Nicola Labanca 《Energy Policy》2010
A number of Member States of the European Union (EU) have introduced market-based policy portfolios based on quantified energy savings obligations on energy distributors or suppliers, possibly coupled with certification of project-based energy savings (via white certificates), and the option to trade the certificates or obligations. The paper provides an up-to-date review and analysis of results to date of white certificate schemes in the EU. 相似文献
125.
126.
Isabella Panfoli Daniela Calzia Silvia Ravera Paolo Bianchini Alberto Diaspro 《Microscopy research and technique》2010,73(12):1086-1090
We describe a procedure for the labeling of membranous vesicular purified subcellular fractions, to image them, typically by confocal laser scanning microscopy. Being intracellular organelles, these fractions, once purified cannot be attached to glass slides as for cells. Fractions are labeled “in batch” without prior embedding or freezing. Each labeling step performed by passages of resuspension/centrifugation is followed by washings. Then samples are dispersed on the glass slides. Mammalian retinal rod outer segment disks, intact brain stem myelin vesicles, and brain synaptosomes were chosen, as these subcellular fractions can be purified by well established procedures. These fractions were immunolabeled with specific antibodies. Moreover, by the earlier procedure, we show that the mitochondrial vital membrane potential probe MitoTracker Deep Red 633 stains myelin vesicles and rod disks before fixation, consistently with our previous reports of a respiring capacity of these membranes. Therefore, the technique seems adequate to become an instrument to study the structure and the function of these and other subcellular fractions. Microsc. Res. Tech. 73:1086–1090, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
127.
Silvia Rovira Victor Garcia Jose Laencina Maria Belen López 《International Journal of Dairy Technology》2013,66(3):382-389
The microstructural parameters of an industrially manufactured goat cheese curd (pore number, area and perimeter, strand thickness and porosity) were analysed by scanning electron microscopy and image analysis during synaeresis. The water‐holding capacity, whey fat, pH and moisture content were also determined to establish any relationship with the curd microstructure. The quantification of the different microstructural parameters made it possible to assign pitching and stirring as important processing steps because these steps impart different features to the curd microstructure. Higher pore number was related to reduced pore area, perimeter and strand thickness, but higher porosity and moisture. 相似文献
128.
This study used flow cytometry (FC), epifluorescent microscopy (EM), and conventional culture media (PC) to evaluate the potential for high‐pressure throttling (HPT) to produce injury in E. coli. E. coli cells suspended at a concentration of approximately 8 log (CFU/mL) in Butterfield's phosphate buffer and UHT skimmed milk, were treated with HPT at pressures ranging from 35 to 283 MPa. Cells were stained with SYTO 9 and propidium iodide (Live/Dead Baclight kit) to assess their membrane integrity. MacConkey and Tryptone Soy agars and a modification of the thin agar layer method were used to determine injured and non‐injured cells. PC results indicated a reduction in E. coli counts as pressure increased but no significant injured population was detected in either matrix. However, FC and EM observations indicated that the membrane integrity of a portion of the bacterial population was affected by HPT, producing different degrees of cell injury that could be sublethal. The percentage of this heterogeneous population increased with applied pressure. These results reassert the importance of understanding the potential of new processing treatments to produce sublethally‐injured bacteria, and developing appropriate detection techniques. 相似文献
129.
130.
Andrea M. A. Araya‐Sibaja Cinira Fandaruff Carlos E. M. Campos Valdir Soldi Simone G. Cardoso Silvia L. Cuffini 《Scanning》2013,35(4):213-221
In this article, morphology of progesterone polymorphs prepared by polymer‐induced heteronucleation (PIHn) technique was studied. Hydroxypropyl methylcellulose(HPMC), such as dextran T‐500 and gelatin G‐9382, polyisoprene (PI), and acrylonitrile/butadiene copolymer (NBR) were used as substrates. The crystallizations were performed by solvent evaporation at room temperature from 0.5, 10, and 40 mg/ml solutions in chloroform and acetone. Progesterone polymorphs were identified by X‐ray diffraction. Differential scanning calorimetry and total attenuated reflectance infrared spectroscopy were used as complementary techniques in the identification. Depending on the polymeric matrix and the concentration used, form 1, form 2, or mixture of both polymorphs were obtained. Scanning electron microscopy pictures evidenced difference in morphology and in homogeneity of the two progesterone polymorphs. These polymorphs prepared by PIHn, did not present a distinctive morphology that allows identifying polymorph by its crystal habit. Hence, polymeric matrix induced the crystallization, affecting polymorphism and morphology. SCANNING 35:213‐221, 2013. © 2012 Wiley Periodicals, Inc. 相似文献