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The purpose of this study was to investigate whether training in a microworld had an effect on the decision-making process in a command-and-control training facility. Fourteen battalion commanders participated in the study. Prior to performing the main task in the command-and-control facility, seven participants (the experimental group) received training in the microworld. Seven participants (the control group) received no training before the main task. The results show that the experimental group performed better than the control group, measured by self-ratings and by fulfilling the instructors’ criteria. The experimental group displayed a different decision-making behaviour in the main task than the control group did. The results indicate that the experimental group used some behaviour characteristics they learnt during training, namely “working systematically” and “causal relationship”. Thus, the study shows that favourable behaviour was learnt in the microworld, and that behaviour was subsequently used in the command-and-control training facility.  相似文献   
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A non-intrusive technique to follow single particles in the fountain region of a spouted bed with draft tube, the Wurster coater, is developed and tested. Compared to other techniques found in literature, the measurement technique presented here is easy to handle, inexpensive and suitable for particles with a diameter down to 500 μm. The measurements are performed in a laboratory scale Wurster bed constructed of Plexiglas to allow optical access to the flow. A small quantity of the particles in the bed are marked with fluorescence. A UV lamp is used to excite the fluorescence and the marked particles are followed with a high-speed video camera equipped with an optical filter. A single marked particle in the fountain can be followed in 5-30 images in sequence at a frame rate of 125 fps. The particle position and velocity are calculated. The distribution of the particle trajectories maximum height is studied for different particle loading, jet air velocity and position of the Wurster tube. The technique can be used for the characterization of differences in process dynamics due to different operating conditions.  相似文献   
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It has been shown many times that cosputtering low-friction coatings of molybdenum disulfide (MoS2) and tungsten disulfide (WS2) with other elements can improve the structural, mechanical, and tribological properties. To achieve the lowest friction, MoS2 or WS2 should be doped with element(s) improving the hardness and density of the coatings. On the other hand, such elements, or their compounds, should not be present in the outermost molecular layers at the sliding interface. This article suggests that there are important differences between how MoS2 and WS2 coatings respond to or react with doping elements, despite the almost identical structure and behavior of the undoped materials. Two systems have been investigated by high-resolution transmission electron microscopy (HRTEM) and scanning TEM (STEM) electron energy loss spectroscopy (EELS), W-S-C-Cr and W-S-C-Ti, and showed significant amounts of oxides, which typically formed a layer just underneath the crystalline WS2 top layer. Further, carbon was almost completely absent in the tribofilms, despite the fact that the as-deposited coatings contained as much as 40–50 at% C. An interesting observation here is that WS2 basal planes surround or embed Fe wear particles, suggesting a relatively strong adhesion or a Fe-S chemical bonding between iron/steel and WS2. The result of this is that the wear particles become pacified and remain in the contact as low-friction material.  相似文献   
35.
Injection moulding processing of composite materials most often includes infiltration of a thermoset resin into a multi‐scale porous fabric. Controlling the fluid flow within the multi‐scale fabric is essential for the quality of the final composite material, since the transport of fluid between regions with different scales is of importance for phenomena such as void formation and filtration of particle doped resins. Hence, the transient flow behaviour in dual scale porous media is investigated in detail with Micro Particle Image Velocimetry. These experiments show that the fluid transport between the two scales can be controlled by the injection velocity. Validation of the measured velocity fields furthermore shows excellent agreement with theory and that transport between the two scales can be substantial at the flow front but negligible up‐stream it. POLYM. COMPOS., 31:1232–1240, 2010. © 2009 Society of Plastics Engineers  相似文献   
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Plant cell walls are complex structures composed of high-molecular-weight polysaccharides,proteins,and lignins. Among the wall polysaccharides,cellulose,a hydrogen-bonded β-1,4-linked glucan microfibril,is the main load-bearing wall component and a key precursor for industrial applications. Cellulose is synthesized by large multi-meric cellulose synthase (CesA) complexes,tracking along cortical microtubules at the plasma membrane. The only known components of these complexes are the cellulose synthase proteins. Recent studies have identified tentative interaction partners for the CesAs and shown that the migratory patterns of the CesA complexes depend on phosphorylation status. These advances may become good platforms for expanding our knowledge about cellulose synthesis in the near future. In addition,our current understanding of cellulose chain polymerization in the context of the CesA complex is discussed.  相似文献   
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An exploratory focus group study of people with different types of disabilities, e.g. mobility, visual and auditory, was carried out to explore how evacuation safety in historical buildings can be improved for people with various disabilities. Accounts of real life experiences on how well evacuation routes in historical buildings are adapted to people with different types of disabilities, as well as suggestions for safety enhancing measures, were collected. Some examples of reported problems were level differences on the way to and in evacuation routes for people with mobility impairments. Other examples were problems with orientation for people with visual disabilities and problems with detecting the evacuation alarm signal for people with auditory disabilities. In general the participants expressed different problems and needs depending on their type of disability. A common view amongst all the participants were that organizational parameters concerning evacuation of people with disabilities have to be improved. One conclusion from the study was that there are shortcomings in the physical environment as well as in the organization of evacuation in historical buildings today. This means that emergency evacuation safety must be properly focused on when improving accessibility in historical buildings. Measures must be taken to address the different needs of people with various types of disabilities as well as to make improvements for all user groups.  相似文献   
40.
This article presents numerical simulations of the laminar flow of lubricating greases in a channel with rectangular cross section. Three greases with different consistencies (NLGI grades 00, 1, and 2) have been considered in three different configurations composed of a rectangular channel without restrictions, one rectangular step restriction, and one double-lip restriction. The driving pressure drop over the channel spans from 30 to 250 kPa. The grease rheology is described by the Herschel-Bulkley rheology model, and both the numerical code and rheology model have been validated with analytical solutions and flow measurements using micro-particle image velocimetry.  相似文献   
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