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1.
By contrast to design meetings, design evaluation meetings (DEMs) have generally been considered as situations in which, according to DEM methodologies, design activities are quite marginal. In a study of DEMs in software development, i.e. in technical review meetings following a particular review methodology, we showed: (i) the occurrence of design activities as part of an argumentation process; (ii) the relative importance of cognitive synchronisation as a prerequisite for evaluation; (iii) the important role played in evaluation by argumentation that makes explicit the underlying design rationale (DR). On the basis of our results, we discuss the potential for using DR methodologies in this kind of meetings.  相似文献   
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A study, both analytical and experimental, has been made on the natural convection induced by an isothermal vertical plate immersed in a large volume of water at a temperature which was close to its freezing point. A particular attention has been paid to the effects resulting from the non-linearity existing between the density of water and its temperature. when the latter was close to 4°C. The plate temperature (Tw) was in the range from 8.0°C to 27.2°C, while the water temperature (Ti) varied between 0°C and 22.2°C. The Prandtl numbers for the flow were in the range from 6.4 to 13.7. An excellent agreement between the theoretical solution and the experimental data has been observed.  相似文献   
4.
A study, both analytical and experimental, has been made on the natural convection induced by an isothermal vertical plate immersed in a large volume of water at a temperature which was close to its freezing point. A particular attention has been paid to the effects resulting from the non-linearity existing between the density of water and its temperature. when the latter was close to 4°C. The plate temperature (Tw) was in the range from 8.0°C to 27.2°C. while the water temperature (Ti) varied between 0°C and 22.2°C. The Prandtl numbers for the flow were in the range from 6.4 to 13.7. An excellent agreement between the theoretical solution and the experimental data has been observed.  相似文献   
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Nearshore small fish species represent a large proportion of fish biodiversity in Lake Simcoe, a large inland lake in southern Ontario, Canada. Over the past 30 years, Lake Simcoe has experienced several changes to its aquatic habitat, benthic invertebrate communities and predatory fish populations. This study compared samples of the nearshore small fish community in three geographic areas of Lake Simcoe. Fish community data were grouped into two time periods: a contemporary period (2007–2009) and a historical period (1982–1995). The fish community was compared across time periods for each area to assess if observed ecological changes had an impact on the small fish community. Species richness significantly declined between time periods in two areas (Cook's Bay and the southeast shoreline), the number of individuals captured declined between time periods in one area of the lake (Kempenfelt Bay) and Simpson's diversity index declined between time periods in one area of the lake (southeast shoreline). There were no significant differences in the Shannon–Weiner evenness index between time periods in any of the study areas. Additional analyses of intra- and inter-annual variation in fish sampling results generally supported the findings that shifts in the fish community occurred between time periods. Overall, this study suggests that the nearshore small fish biodiversity of Lake Simcoe has shifted over time but these shifts are not clearly related to recent increases in water clarity, macrophyte growth and nearshore benthic invertebrate densities.  相似文献   
6.
Effects of Botrytis cinerea infection on Champagne wine foaming properties   总被引:1,自引:0,他引:1  
Qualitative effects of Botrytis cinerea infection were studied by comparing the foaming properties of Champagnes obtained from healthy grapes with those from grapes infected by B cinerea. This is of particular interest when it is considered that the foaming properties of Champagne wines are important in terms of product attractiveness for the consumer. Experiments using artificial viewing equipment clearly showed the dramatic effects on Champagne foam characteristics when grape berries were highly infected. The speed at which liquid separated from the foam (expressed as liquid height LS) in the glass depended largely on the level of infection for Chardonnary and Pinot noir wines (+268% for Chardonnary wines at 40% infection and +627% for Pinot noir wines at 20% infection). B cinerea infection reduced the time (LT) at which liquid first appeared in the glass; for Pinot noir wines an infection level of 20% caused very rapid drainage. The time of pouring (PT, ie the time to fill the glass under controlled conditions) also diminished considerably at an infection level of 20% for both Pinot noir and Pinot meunier wines (?74 and ?58% respectively). Mouldiness considerably altered the foam height observed 80 s (H80) after the start of pouring (?83% for Pinot noir and ?89% for Pinot meunier at 20% infection). Champagne foamability was also quantified using a sparging technique to standardise effervescence. Foamability suffered considerably (?60 to ?65%) when the B cinerea infection level was 20% as compared to control Champagnes. All wines studied had low and very similar protein contents. Differences in the concentrations of these compounds, which are generally implicated in the formation of foam in sparkling wines, could not explain the differences in Champagne foaming properties observed here. © 2001 Society of Chemical Industry  相似文献   
7.
Conducted 2 cancellation tests, Albert's Test and the Bells Test, which are both used for the evaluation of unilateral visuospatial neglect, with 40 neurologically normal adults and 47 right cerebrovascular accident patients (aged 32–87 yrs), 4–22 wks after stroke. Norms are proposed for both tests. Results show that the Bells Test has greater discrimination power than Albert's Test. In both tasks, a left-to-right gradient of neglect is found in Ss who show neglect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
This paper presents a new representation of control flow graphs which is readable and concise, keeping all pertinent information as it appears in the source code. The iconic control graph provides an exact transformation of the source code. It is a basis for control flow visualization, unstructuredness identification, path crossing and path computation. The representation is programming-language independent. The iconic control flow construction is automated.  相似文献   
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Quasi-steady state laminar natural convection in an inclined porous layer is studied analytically and numerically. On the basis of the Darcy-Oberbeck-Boussinesq equations, the problem is solved analytically in the limit of a thin porous layer heated on one side by a constant heat flux while the other boundaries are maintained adiabatic. For quasi-steady state, the flow and temperature fields and overall heat transfer rates are obtained in terms of the controlling parameters and the onset of convection in a bottom-heated horizontal system is predicted. It is also demonstrated for the case of a bottom-heated layer that for sufficiently small inclinations, multiple unicellular quasi-steady states exist, some of which are unstable. A numerical study of the same phenomenon, obtained by solving the complete system of governing equations, is conducted. Good agreement is found between the analytical predictions and the numerical simulation.  相似文献   
10.
Cytomegalovirus (CMV) antigenemia was directly detected in polymorphonuclear leukocytes (PMNLs) from transplant recipients by using flow cytometry (FC). Two fixation and permeabilization methods and seven anti-CMV monoclonal antibodies (MAbs) were evaluated. 1C3, SL20, and NEA-9221 MAbs were more efficacious. The antigenemia detection threshold of FC was 0.05% positive PMNLs, and percentages correlated well with DNA viral load and the appearance of clinical symptoms.  相似文献   
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