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61.
The distribution of trace metals in a ling (Genypterus blacodes) fish fillet was determined from ICP-MS measurements of digests prepared using nitric acid and hydrogen peroxide, followed by microwave digestion. Most trace elements were inhomogeneously distributed in the muscle tissue of the ling with a non-linear increase in concentration towards the tail end of the fillet. This distribution pattern may be connected to the size variation of the individual muscle cells or the change in the ratio of connective tissue to muscle tissue, suggesting that the observed inhomogeneity of muscle elemental distribution may be inherent to all fish species. The concentration of an element in a sample of fish muscle tissue thus depends on the physical location within the fish from which the sample was dissected. Significant differences in trace element concentrations were also detected between the red and white muscle fibres of ling, as well as between the belly flap and the rest of the musculature. 相似文献
62.
Jinchang Ren Ming Xu James Orwell Graeme A. Jones 《Machine Vision and Applications》2010,21(6):855-863
Soccer analysis and reconstruction is one of the most interesting challenges for wide-area video surveillance applications.
Techniques and system implementation for tracking the ball and players with multiple stationary cameras are discussed. With
video data captured from a football stadium, the real-world, real-time positions of the ball and players can be generated.
The whole system contains a two-stage workflow, i.e., single view and multi-view processing. The first stage includes categorizing
of players and filtering of the ball after changing detection against an adaptive background and image-plane tracking. Occlusion
reasoning and tracking-back is applied for robust ball filtering. In the multi-view stage, multiple observations from overlapped
single views are fused to refine players’ positions and to estimate 3-D ball positions using geometric constraints. Experimental
results on real data from long sequences are demonstrated. 相似文献
63.
Nuri Ersoy Tomasz Garstka Kevin Potter Michael R. Wisnom David Porter Graeme Stringer 《Composites Part A》2010,41(3):410-418
In this study, a simple two step finite element model is developed to predict the spring-in of C-sections parts made of AS4/8552 composite. The development of resin properties throughout the MRCC were derived using Group Interaction Modelling and the mechanical properties of the composite predicted by using micromechanical models. Important mechanisms during manufacturing that are effective in the formation of residual stresses and shape distortions are defined. The finite element method implemented is composed of two steps before and after the vitrification of the resin. Vitrification is treated as a point at which the material suddenly changes from the rubbery to glassy state with constant properties in each state. The spring-in angles predicted by the finite element analysis are compared to the angles measured on C-section specimens of various lay-ups and thicknesses. The correlation is good showing the validity of the assumptions adopted. 相似文献
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65.
The Inter-organisational systems (IOS) Motivation Model (IMM) has recently been proposed as a theory that explains variations
in IOS implementation processes initiated by organisations. The IMM classifies IOS adoption projects (regardless of the underlying
technology used) into four generic motivation scenarios and explains different implementation processes for each motivation
scenario. The theory was tested in the Australian pharmaceutical industry where it received broad support. In order to enhance
its generality, in this study we explore the applicability of part of the IMM theory to a different industry context by addressing
the research objective that organisations with the same motive for implementing an IOS initiate the same implementation activities
regardless of differences in the industry contexts within which they operate. We have used a multiple case study approach
and compared the implementation of a proprietary in-house built e-ordering system in a large Australian pharmaceutical manufacturing
company with that of a web-based EDI system used by a large automotive manufacturing company using IMM as a theoretical lens.
The empirical results indicate a striking similarity in the implementation processes of these two different IOS applications;
this can largely be explained using the IMM theory. Furthermore, the differences in industry contexts do not appear to have
a direct influence on the activities associated with implementing these systems. 相似文献
66.
Abstract Patterns of water supply and use in Australia and the U.S.A. differ in many ways. This results in different perceptions concerning the nature of drought and policy approaches to its management. This paper discusses the differences and similarities and explores lessons that policy makers in both countries can learn from one another. A key difference between the two countries is that whereas drought is perceived in Australia essentially in terms of its impact on agriculture, in the U.S. both perceptions and policy are also heavily influenced by the impact of drought on urban communities. This has led to different policy emphases. In 1992 Australia established its National Drought Policy; the U.S. is presently considering the adoption of a national drought policy. These policies highlight drought being accepted as part of natural climate variability, rather than as a natural disaster. They also emphasize the protection of the natural resource base. 相似文献
67.
68.
RA Blackwood AT Transue DM Harsh RC Brower SJ Zacharek JE Smolen RJ Hessler 《Canadian Metallurgical Quarterly》1996,59(5):663-670
Neutrophil stimulation results in the activation of a variety of phospholipases, including phospholipase A2 (PLA2), which releases arachidonic acid from the 2 position of membrane phospholipids, leaving a lysophospholipid. Because arachidonic acid is known to be a potent fusogen in vitro, we examined the effect of metabolism by PLA2 on the fusion of complex liposomes (liposomes prepared with a phospholipid composition similar to that found in neutrophil plasma membrane). We observed that PLA2 augmented the fusion of complex liposomes with each other as well as with specific granules isolated from human neutrophils, lowering the Ca2+ requirement for fusion by three orders of magnitude. Furthermore, although lysophospholipids inhibited fusion, the incorporation of arachidonic acid into liposome membranes overcame the inhibitory effects of the lysophospholipids. Thus with PLA2 and annexins we were able to obtain fusion of complex liposomes at concentrations of Ca2+ that are close to physiological. Our data suggest that the activation of PLA2 and the generation of arachidonic acid may be the major fusion-promoting event mediating neutrophil degranulation. 相似文献
69.
Graeme Knowles Gordon Vickers Jiju Anthony 《Quality and Reliability Engineering International》2003,19(5):397-410
Reducing process variability is presently an area of much interest in manufacturing organizations. Programmes such as Six Sigma robustly link the financial performance of the organization to the degree of variability present in the processes and products of the organization. Data, and hence measurement processes, play an important part in driving such programmes and in making key manufacturing decisions. In many organizations, however, little thought is given to the quality of the data generated by such measurement processes. By using potentially flawed data in making fundamental manufacturing decisions, the quality of the decision‐making process is undermined and, potentially, significant costs are incurred. Research in this area is sparse and has concentrated on the technicalities of the methodologies available to assess measurement process capability. Little work has been done on how to operationalize such activities to give maximum benefit. From the perspective of one automotive company, this paper briefly reviews the approaches presently available to assess the quality of data and develops a practical approach, which is based on an existing technical methodology and incorporates simple continuous improvement tools within a framework which facilitates appropriate improvement actions for each process assessed. A case study demonstrates the framework and shows it to be sound, generalizable and highly supportive of continuous improvement goals. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
70.