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981.
Peter C. Matthews 《Research in Engineering Design》2011,22(1):29-42
A novel Bayesian design support tool is empirically investigated for its potential to support the early design stages. The
design support tool provides dynamic guidance with the use of morphological design matrices during the conceptual or preliminary
design stages. This paper tests the appropriateness of adopting a stochastic approach for supporting the early design phase.
The rationale for the stochastic approach is based on the uncertain nature of the design during this part of the design process.
The support tool is based on Bayesian belief networks (BBNs) and uses a simple but effective information content–based metric
to learn or induce the model structure. The dynamically interactive tool is assessed with two empirical trials. First, the
laboratory-based trial with novice designers illustrates a novel emergent design search methodology. Second, the industrial-based
trial with expert designers illustrates the hurdles that are faced when deploying a design support tool in a highly pressurised
industrial environment. The conclusion from these trials is that there is a need for designers to better understand the stochastic
methodology for them to both be able to interpret and trust the BBN model of the design domain. Further, there is a need for
a lightweight domain-specific front end interface is needed to enable a better fit between the generic support tool and the
domain-specific design process and associated tools. 相似文献
982.
Takuya Takahashi Motoya Suzuki Ryuji Nomura Yuichi Okuda Koji Kamiya Takenori Numazawa Peter Shirron 《Microgravity science and technology》2011,23(4):365-372
Superfluid 4He was produced on a small jet plane for the first time using a small GM-refrigerator to condense the liquid and a scroll
pump to get the superfluid by evaporation. The surface wave on superfluid under 0.5g
E, 0.1g
E and 0.05g
E, together with 2g
E and 1g
E, was successfully examined by an optical method utilizing parabolic flight. Here, g
E is the gravitational constant on the ground. Assuming that only the fundamental mode was excited as determined by the sample
cell width, the resonance peak in the frequency domain was well reproduced by the gravity wave with corresponding gravity
constant. 相似文献
983.
Abstract The Water Poverty Index is an integrated tool developed on the basis of extensive consultation with a range of scientists, practitioners and policymakers. It is primarily designed for use at the community level to enable more holistic water-resource assessments on a site-specific basis. It can however be applied at different scales to suit different needs. One of the motivations to design such a tool was an attempt to move away from the conventional, purely deterministic, approaches to water assessment, relying primarily on models and large-scale data. In today's world such an approach is inappropriate, ill representing the complexities of modern water-allocation decisions where economic, political and social issues all have a powerful role to play. This paper highlights some applications of the Water Poverty Index at different spatial scales and discusses the implications of applying indicators at these different scales. 相似文献
984.
While the efficacy of PUV-light on microbial inactivation is well documented, its effect on product quality is not well studied. Thus the effect of PUV-light on color, texture and oxidative stability of ham was evaluated. Samples of 100 g raw ham (~5 mm thick) were treated for 60, 90 and 120 s in a UV-light system. Another 100 g of untreated sample was used as a control. The distance from the lamp central axis was varied at 4.5, 8.3 and 14.6 cm. Results showed that the oxidative stability of the control, 4.5 cm/60 s, 4.5 cm/90 s, 4.5 cm/120 s, 8.3 cm/60 s, 8.3 cm/90 s, 8.3 cm/120 s, 14.6 cm/60 s, 14.6 cm/90 s, and 14.6 cm/120 s sample decreased by 21, 67, 53, 54, 39, 71, 75, 56, 58, and 55% respectively after 14 days of storage. Oxidative stability reduction was higher as treatment time was prolonged, but decreased with increased distance from the lamp. Overall, the color and texture of the samples were inversely affected by treatment time and distance of the sample from the lamp. Although PUV-light has a potential to decontaminate food products, this study demonstrated that quality of the product is concurrently compromised. 相似文献
985.
Willmott Lynn; Harris Peter; Gellaitry Grace; Cooper Vanessa; Horne Rob 《Canadian Metallurgical Quarterly》2011,30(5):642
Objective: To assess the effects of expressive writing on health care utilization, clinical variables and subjective quality of life following first myocardial infarction (MI). Methods: One-hundred and seventy-nine first MI patients were randomized to Intervention (N = 88) or Control (N = 91) groups. The intervention group wrote about their thoughts and feelings in relation to having had an MI. Controls wrote in a neutral way about daily activities. The main outcome measures were health care utilization, physical status and subjective quality of life (QOL), assessed after one, two, and five months. Results: One-hundred and fifty-six (87%) completed the study. Five months post-intervention, the intervention group had significantly fewer recorded medical appointments compared to controls. The number of prescribed medicines decreased over time within the intervention group but increased within the control group. The intervention group attended significantly more rehabilitation sessions, reported fewer cardiac related symptoms and had lower diastolic blood pressure five months post-intervention. There was no significant group by time interaction on reported physical health. The group by time interaction on reported mental health approached significance, those in the intervention group reporting greater improvement. Conclusion: Expressive writing may be a beneficial strategy which could be incorporated into rehabilitation interventions to help individuals adjust after first MI. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
986.
987.
Mechanical vibration of the grass and crop weighing lysimeters, located at the University of California West Side Field Research and Extension Station at Five Points, Calif. generated noise in lysimeter mass measurements and reduced the quality of evapotranspiration (ET) data. The estimated power spectral density (PSD) for grass lysimeter mass data acquired at 1.3?ms intervals contained a large peak at 11?Hz. Crop lysimeter data produced similar peaks at frequencies greater than 1?Hz. An effective method for eliminating this noise source is arithmetic averaging of the data, which should be acquired sufficiently rapidly to avoid aliasing. The PSD also increased with decreasing frequency in the range 1.0–0.1?Hz. This noise was addressed by Savitsky–Golay (SG) filtering using 7-, 11-, and 15-point filters. Each filter was applied to the same data set consisting of 2,560 measurements taken during a 1-min interval every 10?min over a 26.3-h period. Noise reduction factors, defined as the ratio of standard deviation of filtered lysimeter mass to standard deviation of unfiltered mean values of lysimeter mass for subsequences of the same data, were 0.90, 0.88, and 0.86 for the 7-, 11-, and 15-point filters, respectively. For the daytime data only, the factors were 0.88, 0.85, and 0.83. The SG filters were more effective during daytime when most of the lysimeter ET occurs. These methods are simple enough to be programmed into commercially available dataloggers for real time filtering. Hourly averages of the standard deviations of lysimeter mass measurements bear a distinct nonlinear relationship to hourly mean wind speed confirming earlier suppositions that wind loading causes noise in counterbalanced weighing lysimeters. 相似文献
988.
Investigations on metal-cutting machining processes that were conducted since the second half of the twentieth century have
considerably contributed to disclosing the principles underlying the cutting process. Although numerous studies have been
carried out on this subject, a generally valid model of the cutting process and the interactions in the separating processes
does not exist yet. Such a model could guarantee the disclosure of the principles of thermodynamic interactions between the
cutting process and the involved machine structure. This contribution is twofold and presents an experimental setup used to
determine cutting forces and temperatures in orthogonal cutting processes. The results are then used as a reference for simulations
made with the Discrete Element Method (DEM). The DEM is due to its meshless nature well suited to capture large deformations
and rupture of material which is included very naturally. It is examined to which extent the measured results can be captured
with the DEM model. 相似文献
989.
Andrea D Lehmann Fabian Blank Oliver Baum Peter Gehr Barbara M Rothen-Rutishauser 《Particle and fibre toxicology》2009,6(1):26
Background
Using an in vitro triple cell co-culture model consisting of human epithelial cells (16HBE14o-), monocyte-derived macrophages and dendritic cells, it was recently demonstrated that macrophages and dendritic cells create a transepithelial network between the epithelial cells to capture antigens without disrupting the epithelial tightness. The expression of the different tight junction proteins in macrophages and dendritic cells, and the formation of tight junction-like structures with epithelial cells has been demonstrated. Immunofluorescent methods combined with laser scanning microscopy and quantitative real-time polymerase chain reaction were used to investigate if exposure to diesel exhaust particles (DEP) (0.5, 5, 50, 125 μg/ml), for 24 h, can modulate the expression of the tight junction mRNA/protein of occludin, in all three cell types. 相似文献990.
Aiping Zeng Marcela M.M. Bilek David R. McKenzie Peter A. Lay 《Diamond and Related Materials》2009,18(10):1211-1217
The semiconductor capacitances of the nitrogen-doped amorphous carbon (a-C:N) materials with different sp3/sp2 C ratios were studied as a function of electrode potential in a-C:N/aqueous electrolyte systems. This dependence of capacitance on electrode potential in aqueous 0.1 M NaOH shows that the investigated a-C:N materials are intrinsic semiconductors. The space-charge layers inside the a-C:N electrodes behave similar to a Helmholtz layer because of the presence of surface states when the electrolytes contain O2 or anions other than OH−. The lower density and mobility of carriers of materials with a higher sp3 C fraction within the a-C:N material causes a suppression of redox reactions, and the lower density of carriers contributes to a lower capacitance. 相似文献