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51.
The objective of this qualitative study was to assess whether a hypothesised sequential order of behavioural change phases would be fulfilled in different groups of stakeholders involved at the start of a process to implement ergonomic measures in bricklaying teams. The measures include trestles, bricklaying scaffolds, mast climbing work platforms and cranes. The behavioural change phases were: (1) being aware of measures, (2) understanding measures, (3) wanting measures, (4) intention to buy or hire measures, (5) ability to use measures, (6) using measures (experience), and (7) continuing to use measures. Structured interviews were conducted to examine the change phases in two groups of stakeholders (employers/work planners (n=11) and foremen/bricklayers (n=9) from nine companies) thought to be relevant in the decision to adopt and use the ergonomic measures. The results show that the fulfilled behavioural change phases differ between individual stakeholders, groups of stakeholders, companies and also between ergonomic measures. The hypothesised order of fulfilled consecutive behavioural change phases for individual stakeholders has not been confirmed by this study. The relationship between fulfilled and unfulfilled change phases by each stakeholder (group) and actual use of each ergonomic measure requires further study, so as to improve the selection of suitable implementation strategies. 相似文献
52.
Cover Picture: Reconstructing the Discontinuous and Conformational β1/β3‐Loop Binding Site on hFSH/hCG by Using Highly Constrained Multicyclic Peptides (ChemBioChem 1/2015) 下载免费PDF全文
53.
Zhang Tianci Wang Haitao Li Zhengcao Schut Henk Zhang Zhengming He Ming Sun Yuliang 《金属学报》2018,(4):512-518
The reactor pressure vessel (RPV) is the key component in the nuclear power plant, which is considered irreplaceable and can be the life-limiting feature of the operation of nuclear power plant if its mechanical properties degrade sufficiently. High temperature gas-cooled reactor (HTGR) has perfect inherent safety, which is intended to be one of the fourth generation advanced nuclear reactors. However, HTGR has different service temperature with pressurized water reactor (PWR), that the service temperature of HTGR is 250 degrees C and that of PWR is 290 degrees C. So the irradiation behaviour of RPV in HTGR is expected to be investigated. In this wok, 3 MeV Fe-ion irradiation was performed on Chinese A508-3 reactor pressure vessel steel which is employed by high-temperature gas-cooled reactors and pure Fe under room temperature (about 25 degrees C) and high temperature (250 degrees C). The ion doses were 0.1, 0.5 and 1.0 dpa for both room temperature irradiation and high temperature irradiation. SRIM modeling was performed before irradiation experiments to guide the experimental details. Positron annihilation Doppler broadening (PADB) spectroscopy experiments and nano-indentation tests (to study embrittlement behavior) were conducted for characterization. It is found that after both room temperature irradiation and high temperature irradiation, the densities of defects in the reactor pressure vessel steel and pure Fe increase, and the type of defects could be vacancy-type and solute cluster type from PADB results. The vacancy-type defect density under high temperature irradiation is lower than that under room temperature irradiation. That is because high temperature can recover the defects formed during irradiation. The hardness test results show that for both the reactor pressure vessel steel and pure Fe, the irradiation hardening increases with increasing dose. Compared to room temperature irradiation, high temperature irradiation can produce more solute clusters and fewer vacancy-type defects in the reactor pressure vessel steel. So the irradiation hardening of the reactor pressure vessel steel might be caused mainly by the formation of solute clusters. 相似文献
54.
Alexander Semmler Susanna Moskau Andreas Grigull Susan Farmand Thomas Klockgether Yvo Smulders Henk Blom Bernd Zur Birgit Stoffel-Wagner Michael Linnebank 《Nutrition journal》2010,9(1):1-4
Background
Several studies demonstrated an association of homocysteine plasma levels and the plasma lipoprotein profile. This cross-sectional pilot study aimed at analyzing whether blood levels of the two important cofactors of homocysteine metabolism, folate and vitamin B12, coincide with the lipoprotein profile.Methods
In a retrospective single center approach, we analyzed the laboratory database (2003-2006) of the University Hospital Bonn, Germany, including 1743 individuals, in whom vitamin B12, folate and at least one lipoprotein parameter had been determined by linear multilogistic regression.Results
Higher folate serum levels were associated with lower serum levels of low density lipoprotein cholesterol (LDL-C; Beta = -0.164; p < 0.001), higher levels of high density lipoprotein cholesterol (HDL-C; Beta = 0.094; p = 0.021 for trend) and a lower LDL-C-C/HDL-C-ratio (Beta = -0.210; p < 0.001). Using ANOVA, we additionally compared the individuals of the highest with those of the lowest quartile of folate. Individuals of the highest folate quartile had higher levels of HDL-C (1.42 ± 0.44 mmol/l vs. 1.26 ± 0.47 mmol/l; p = 0.005), lower levels of LDL-C (3.21 ± 1.04 mmol/l vs. 3.67 ± 1.10 mmol/l; p = 0.001) and a lower LDL-C/HDL-C- ratio (2.47 ± 1.18 vs. 3.77 ± 5.29; p = 0.002). Vitamin B12 was not associated with the lipoprotein profile.Conclusion
In our study sample, high folate levels were associated with a favorable lipoprotein profile. A reconfirmation of these results in a different study population with a well defined status of health, diet and medication is warranted. 相似文献55.
<正>交异性钢桥面板改造的问题在于既有钢板与第二个钢板的粘结,以降低应力和增加正交异性钢板的使用寿命。通过试验和分析,对梁的弯曲性能进行参数研究。试验考虑不同厚度、温度和跨度的影响。从试验结果可见,应力降低与温度无关。最小化第二块钢板的厚度及最大化粘结层厚度,可降低重量,增加组合结构的刚度,这是最有效的解决方法。组合梁的弹性性能和屈服荷载取决于钢板的性能,温度的影响不显著。然而,粘结层的受剪最终导致梁的破坏,而粘结层的性能受温度的影响较大。 相似文献
56.
Maarten Hoeijmakers Viktor Kornilov Ines Lopez Arteaga Philip de Goey Henk Nijmeijer 《Combustion and Flame》2014
This paper shows that a flame can be an intrinsically unstable acoustic element. The finding is clarified in the framework of an acoustic network model, where the flame is described by an acoustic scattering matrix. The instability of the flame acoustic coupling is shown to become dominating in the limit of no acoustic reflections. This is in contrast to classical standing-wave thermoacoustic modes, which originate from the positive feedback loop between system acoustics and the flame. These findings imply that the effectiveness of passive thermoacoustic damping devices is limited by the intrinsic stability properties of the flame. 相似文献
57.
Vincent Nollet Diederik Verkest Henk Corporaal 《Journal of Signal Processing Systems》2010,60(2):251-268
The multiprocessor SoC (MPSoC) revolution is fueled by the need to execute multiple advanced multimedia applications on a
single embedded computing platform. At design-time, the applications that will run in parallel and their respective user requirements
are unknown. Hence, a run-time manager (RTM) is needed to match all application needs with the available platform resources
and services. Creating such a run-time manager requires two decisions. First, one needs to decide what functionality to implement.
Second, one has to decide how to implement this functionality in order to meet boundary conditions like e.g. real-time performance.
This paper is the first to detail a generic view on MPSoC run-time management functionality and its design space trade-offs.
We substantiate the run-time components and the implementation trade-offs with academic state-of-the-art solutions and a brief
overview of some industrial multiprocessor run-time management examples. We show a clear trend towards more hardware acceleration,
a limited distribution of management functionality over the platform and increasing support for adaptive multimedia applications.
In addition, we briefly detail upcoming run-time management research issues. 相似文献
58.
Normally Oriented Adhesion versus Friction Forces in Bacterial Adhesion to Polymer‐Brush Functionalized Surfaces Under Fluid Flow 下载免费PDF全文
Jan J. T. M. Swartjes Deepak H. Veeregowda Henny C. van der Mei Henk J. Busscher Prashant K. Sharma 《Advanced functional materials》2014,24(28):4435-4441
Bacterial adhesion is problematic in many diverse applications. Coatings of hydrophilic polymer chains in a brush configuration reduce bacterial adhesion by orders of magnitude, but not to zero. Here, the mechanism by which polymer‐brush functionalized surfaces reduce bacterial adhesion from a flowing carrier fluid by relating bacterial adhesion with normally oriented adhesion and friction forces on polymer (PEG)‐brush coatings of different softness is studied. Softer brush coatings deform more than rigid ones, which yields extensive bond‐maturation and strong, normally oriented adhesion forces, accompanied by irreversible adhesion of bacteria. On rigid brushes, normally oriented adhesion forces remain small, allowing desorption and accordingly lower numbers of adhering bacteria result. Friction forces, generated by fluid flow and normally oriented adhesion forces, are required to oppose fluid shear forces and cause immobile adhesion. Summarizing, inclusion of friction forces and substratum softness provides a more complete mechanism of bacterial adhesion from flowing carrier fluids than available hitherto. 相似文献
59.
Henk Tobias 《Network Security》2000,2000(6):9-11
As more and more organizations conduct business over the Internet, the need to securely identify users across the anonymity void of the Internet has never been more paramount. EEMA, the non-profit making trade organization for electronic business in Europe, has been at the forefront in the fight to create a legal framework for online identification, placing the issue high on the agenda at this year’s ISSE conference in October. 相似文献
60.
W-based versus latent variables spatial autoregressive models: evidence from Monte Carlo simulations
In this paper, we compare by means of Monte Carlo simulations two approaches to take spatial autocorrelation into account:
the classical spatial autoregressive model and the structural equations model with latent variables. The former accounts for
spatial dependence and spillover effects in georeferenced data by means of a spatial weights matrix W. The latter represents
spatial dependence and spillover effects by means of a latent variable in the structural (regression) model while the observed
spatially lagged variables are related to the latent spatial dependence variable in the measurement model. The simulation
results based on Anselin’s Columbus, Ohio, crime data set show that the misspecified latent variables approach slightly trails
the correctly specified classical approach in terms of bias and root mean squared error of the coefficient estimators. 相似文献