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11.
The measurement of the flow through complex combined sewer overflow structures in the frame of automated monitoring remains difficult. In this paper, a methodology based on the use of computational fluid dynamics (CFD) modelling in order to improve the instrumentation of a downstream-controlled dual-overflow structure is presented. The dual-overflow structure is composed of two combined sewer overflows (CSOs) connected by a rectangular channel and controlled by a downstream gate located at the entry of the Meyzieu waste water treatment plant (close to Lyon, France). The analysis of the CFD results provides: (i) a better understanding of the interaction between the two CSOs--that means the hydraulic operation, the hydrodynamic behaviour, the backflow effect--and (ii) an ability to optimise the location of the water depth sensor. The measured water depth is used to assess the overflow rate by means of a numerical relationship. Uncertainties are also assessed.  相似文献   
12.
This paper presents a framework for augmenting independent validation and verification (IV&V) of software systems with computer-based IV&V techniques. The framework allows an IV&V team to capture its own understanding of the application as well as the expected behavior of any proposed system for solving the underlying problem by using an executable system reference model, which uses formal assertions to specify mission- and safety-critical behaviors. The framework uses execution-based model checking to validate the correctness of the assertions and to verify the correctness and adequacy of the system under test.  相似文献   
13.
A problem with current database systems is the limitation placed on the type of data which may be represented and manipulated within such systems. In an attempt to broaden this to a wider class of data (i.e. rules as well as facts) and a more powerful set of manipulations, the concept of a deductive database was introduced. However, for the sake of efficiency the type of rule which is allowed in a deductive database is restricted in form. This paper surveys a number of attempts to move towards less restrictive forms of rules in deductive databases which allow indefinite and negative data to be handled.  相似文献   
14.
The intelligent manufacturing systems of the future will be highly productive and effective, but they may have undesirable social effects as well as beneficial ones. Possible motivations for developing them are therefore examined against a background of the long, continuing resistance to the use of innovations in production machinery since the start of the industrial revolution. The claim that advanced computer-integrated manufacturing technology has a specially beneficial effect on the prosperity of nations is critically examined, as well as the nature of the beneficial synergism between manufacturing and services in creating wealth. A sombre view is taken of international competition which seems to be leading to an “ultimate” competitive race. The continuing substantial reductions expected in manufacturing employment may be much greater than any compensating employment increase in the service sector, owing to the application of the new technologies in this sector which is only now getting under way. Because full employment in traditional form is now widely seen to be an unattainable goal, a social revolution is required in attitudes to employment, work and its value. The paper ends with a proposal to consider ways of creating new social and economic structures in order to make this social revolution a practical reality, before social catastrophe occurs.  相似文献   
15.
Excretion was studied of catecholamines and diphenilamine (DOPA) in 310 patients with carcinoma of the stomach and large intestine and 43 patients with non-malignant diseases. The oncological patients showed decrease in activity of the mediator link of the sympathoadrenal system (SAS) as well as its reserves but there was no association with sex, age, location or histological structure. Three types of SAS functioning were identified, such as compensation, overstrain and emaciation. Surgical intervention led to activation of the hormonal link and exhaustion of the system's reserves. Two kinds of sympathoadrenal response to stress were described--adequate and inadequate. In the former type, phases of stress remain as they are, unchanged, as are time periods of formation thereof, while under the latter one time periods of the phases formation or formation thereof get disordered.  相似文献   
16.
Covalently attached, non-leaching biocidal-moieties are being explored as an environmentally friendly option for replacing antimicrobial coatings that release biocides. This review highlights studies on antimicrobial surface treatments and coatings in which the antimicrobial agent is covalently bound (i.e. tethered) to the surface or coating matrix. In addition, test methods for measuring antimicrobial surface activity are reviewed, and a discussion of advantages and disadvantages of the various methods is provided.  相似文献   
17.
18.
An array of perfectly alternating polycarbonate‐polydimethylsiloxane (PC‐PDMS) multiblock copolymers possessing systematic variations in block molecular weights were successfully produced by coupling preformed PC and PDMS telechelic oligomers using hydrosilylation. Based on gel permeation chromatography results, the multiblock copolymers were essentially void of the oligomeric precursors. Despite the relatively large difference in solubility parameter between PC and PDMS, the multiblock copolymers exhibited significant partial miscibility between the two phases. As expected, the degree of partial miscibility was dependent on the molecular weight of the blocks with the extent of partial miscibility increasing with decreasing block molecular weights. Morphological characterization using small angle X‐ray scattering showed that, at a given PC block molecular weight, the uniformity of the two phase morphology increased with increasing PDMS block molecular weight, which is consistent with a decrease in the extent of phase mixing with increasing PDMS block molecular weight. POLYM. ENG. SCI., 54:1648–1663, 2014. © 2013 Society of Plastics Engineers  相似文献   
19.
Novel antimicrobial copolymers were produced by first converting the commodity biocide, triclosan (TCS), to an epoxy-functional derivative, 2-((5-chloro-2-(2,4-dichlorophenoxy)phenoxy) methyl)oxirane (ETCS), and then reacting ETCS with polyethylenimine (PEI). While neither ETCS or PEI showed high antimicrobial activity toward either the Gram-positive bacterium, Staphylococcus epidermidis, or the Gram-negative bacterium, Escherichia coli, some the copolymers showed very high activity toward both bacteria. Antimicrobial activity for these copolymers was found to be highly dependent on both the molecular weight of the PEI utilized and the concentration of pendent groups derived from ETCS. In general, decreasing PEI molecular weight and increasing TCS pendent group concentration increased antimicrobial activity. Surface tension measurements showed that the molecular parameters affecting antimicrobial activity also affected surface activity in a similar fashion. Thus, it was speculated that the mechanism of antimicrobial activity associated with these copolymers involves interaction of the copolymers with the bacterial cell wall. A comparison of the antimicrobial activity of the most effective copolymers to TCS showed that the copolymers were more effective toward E. coli than pure TCS when compared using an equivalent TCS content (i.e. TCS pendent group content for the copolymers). This characteristic coupled with the fact that the TCS-containing copolymers are highly aqueous soluble liquids as opposed to a crystalline solid of limited solubility may afford utility of these copolymers for a variety of applications.  相似文献   
20.
Combinatorial chemistry has proven to be a valuable tool for the development of new compounds. In the pharmaceutical industry, where combinatorial chemistry began, the approach has been instrumental in the high-speed development of new drugs. Due to the overwhelming success of the combinatorial methodology in the pharmaceutical industry, it has been recently applied to materials development. We have recently developed a combinatorial factory capable of preparing and evaluating on the order of 100 organic clear coatings in a day.

One of the most challenging aspects of the creation of the combinatorial factory was the development of the high throughput screening (HTS) methods for the primary coating properties of interest such as optical clarity, abrasion resistance, adhesion, and weatherability. For each property, an entirely new method was developed that allowed for rapid measurement of these properties on very small samples. This paper describes various aspects of the development of these novel measurement systems including the correlation of the HTS methods with conventional, industry standard measurement methods.  相似文献   

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