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51.
There has been a recent increase in desalination projects in an effort to meet the growing demand for clean water. Desalination plants, like other large public service infrastructure, are capital intensive with long asset lives. This makes them prime vehicles to introduce private sector investment both equity and debt. Key to attracting the private sector, particularly International investors, is a well-developed commercial framework for the project following principles widely seen and understood by private investors. Desalination plants can easily fit into well-tested structures, which optimize the risk profile for each stakeholder, e.g. the consumer, the public sector authority, the equity investor/developer, the lenders; and reward each of them appropriately. This paper seeks to introduce a typical project financing structure and compare desalination to other infrastructure projects, which are also competing in the International arena for private investment. Given the success of recent private sector investment in desalination, and the growing demand for clean drinking water, it could be expected that this industry should continue to attract its fair share of the International investor community.  相似文献   
52.
The authors investigated autobiographical memory specificity in subjects who formerly had depression. In 122 euthymic patients with at least two previous major depressive episodes, memory specificity was significantly impaired compared to matched control participants but not related to residual symptoms and illness characteristics, was not differentially affected by cognitive therapy, and was also not predictive of relapse/recurrence during the 2-year follow-up. However, memory specificity was associated with age, education, and immediate and delayed memory recall. The results suggest that memory specificity may reflect a global cognitive impairment that remains in patients who (formerly) had depression but does not constitute a trait marker for vulnerability for relapse/recurrence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
The TR2004 transport formulations for clay, silt, and sand as proposed in Parts 1 and 2 have been implemented in morphodynamic models to predict bed level changes. These models have been verified using various laboratory and field data cases concerning coastal flow in offshore and near-shore zones. Furthermore, the model has been applied to two complicated sediment environments concerning the flow around a spurdike in a river and the tidal flow of cohesive sediments in the Yangtze Estuary in China. Overall, it is concluded that the morphodynamic models using default settings performs reasonably well. The applied scaling factors of the sediment transport model are in the generally accepted range of 0.5–2.  相似文献   
54.
We define bisimulations for temporal logic with Since and Until. This new notion is compared to existing notions of bisimulations, and then used to develop the basic model theory of temporal logic with Since and Until. Our results concern both invariance and definability. We conclude with a brief discussion of the wider applicability of our ideas.  相似文献   
55.
Good memorability of licence plates is important in those cases where licence plates are viewed for a brief period of time and the information is essential for police investigations. The purpose of the current study was to design a new Dutch licence plate that could be remembered well. A memory experiment was conducted, in which 16 different character arrangements were presented for both 450 and 550 ms to 48 participants with ages varying between 20 and 57 years. Participants had to rehearse the stimuli for 6 s, after which they had to be written down. Based on literature on short-term memory for serial order, character arrangements differed on three dimensions: 1) number of alternations between letters and digits; 2) letter to digit ratio; and 3) equality of group size. Results showed that number of alternations between characters of different categories affected memory performance the most. Letter to digit ratio and equality of group size affected memory performance to a lesser, but still significant, extent. A significant interaction between the latter two factors indicates that equal groups only lead to fewer memory errors when more than three letters are used. With three or fewer letters, group size is not a significant factor any more. Based on these results, a new licence plate for Dutch vehicles was recommended, which was subsequently adopted.  相似文献   
56.
Ground surface conditions on construction sites have an important influence on the health and safety of workers and their productivity. The development of an expert-based "working conditions evaluation" system is described, intended to assist site managers in recognising unsatisfactory ground conditions and remedying these. The system was evaluated in the period 2002-2003. The evaluation shows that companies recognize poor soil/ground conditions as problematic, but are not aware of the specific physical workload hazards. The developed methods allow assessment of the ground surface quality and selection of appropriate measures for improvement. However, barriers exist at present to wide implementation of the system across the industry. Most significant of these is that responsibility for a site's condition is not clearly located within contracting arrangements, nor is it a topic of serious negotiation.  相似文献   
57.
CYCLON: Inexpensive Membership Management for Unstructured P2P Overlays   总被引:8,自引:0,他引:8  
Unstructured overlays form an important class of peer-to-peer networks, notably when content-based searching is at stake. The construction of these overlays, which is essentially a membership management issue, is crucial. Ideally, the resulting overlays should have low diameter and be resilient to massive node failures, which are both characteristic properties of random graphs. In addition, they should be able to deal with a high node churn (i.e., expect high-frequency membership changes). Inexpensive membership management while retaining random-graph properties is therefore important. In this paper, we describe a novel gossip-based membership management protocol that meets these requirements. Our protocol is shown to construct graphs that have low diameter, low clustering, highly symmetric node degrees, and that are highly resilient to massive node failures. Moreover, we show that the protocol is highly reactive to restoring randomness when a large number of nodes fail.Spyros Voulgaris is a PhD student in the Computer Systems department at the Vrije Universiteit Amsterdam. He received his MSc degree from the University of Michigan, Ann Arbor, and his BSc degree from the University of Patras, Greece. His research involves peer-to-peer systems, epidemic protocols, and ad-hoc networks. He is a scholarship recipient of the Greek State Scholarships Foundation (IKY) and the Alexander Onassis Foundation.Daniela Gavidia is a PhD student in the Computer Systems group at the Vrije Universiteit Amsterdam. She received her MSc degree from the Universiteit van Amsterdam. Her research interests include peer-to-peer systems and ad-hoc networks. Her recent work focuses on information dissemination in ad-hoc environments.Maarten van Steen is professor of Computer Science at the Vrije Universiteit Amsterdam. His research concentrates on large-scale distributed systems, notably content delivery networks and peer-to-peer systems. He is senior member of the IEEE and member of the ACM.  相似文献   
58.
A novel series of optically active molecules based on a 4‐(2‐(benzhydryloxy)ethyl)‐1‐((R)‐2‐hydroxy‐2‐phenylethyl)‐piperidin‐3‐ol template were developed. Depending on stereochemistry, the compounds exhibit various degrees of affinity for three dopamine, serotonin, and norepinephrine transporters. These molecules have the potential for treating several neurological disorders such as drug abuse, depression, and attention deficit hyperactivity disorder.

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59.
Surface metallization by plasma coating enhances desorption/ionization of membrane components such as lipids and sterols in imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS) of tissues and cells. High-resolution images of cholesterol and other membrane components were obtained for neuroblastoma cells and revealed subcellular details (resolving power 1.5 mum). Alternatively, in matrix-enhanced SIMS, 2,5-dihydroxybenzoic acid electrosprayed on neuroblastoma cells allowed intact molecular ion imaging of phosphatidylcholine and sphingomyelin at the cellular level. Gold deposition on top of matrix-coated rat brain tissue sections strongly enhanced image quality and signal intensity in stigmatic matrix-assisted laser desorption/ionization imaging mass spectrometry. High-quality total ion count images were acquired, and the neuropeptide vasopressin was localized in the rat brain tissue section at the hypothalamic area around the third ventricle. Although the mechanism of signal enhancement by gold deposition is under debate, the results we have obtained for cells and tissue sections illustrate the potential of this sample preparation technique for biomolecular surface imaging by mass spectrometry.  相似文献   
60.
Shelf life of probiotic microorganisms can be retained by drying. Spray drying is an economically interesting alternative to freeze drying with that respect. However, the viability can decrease due to the drying process and testing it is laborious and expensive. This research shows that the viability of Lactobacillus plantarum WCFS1 during pilot scale drying can be predicted with kinetics gathered at a single droplet level. Using this approach, it could be demonstrated that the viability of L. plantarum WCFS1 during spray drying is mainly determined by the combination of temperature and moisture content during the first 0.5 seconds after atomization. The combination of a high moisture content and a high temperature appeared most detrimental to the residual viability. Moreover, it was found to be important to take into account the particle size distribution during atomization when predicting viability, since this has a large effect on the moisture content during this first 0.5 seconds. Finally, it was observed that shelf life during storage was mainly determined by the moisture content of the powder. A lower moisture content resulted in a higher viability. Above a moisture content of 6%, shelf life stability rapidly decreased in the applied maltodextrin (DE = 16) matrix.  相似文献   
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