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991.
This paper shows how a formal method in the form of Coloured Petri Nets (CPNs) and the supporting CPN Tools have been used in the development of the Course of Action Scheduling Tool (COAST). The aim of COAST is to support human planners in the specification and scheduling of tasks in a Course of Action. CPNs have been used to develop a formal model of the task execution framework underlying COAST. The CPN model has been extracted in executable form from CPN Tools and embedded directly into COAST, thereby automatically bridging the gap between the formal specification and its implementation. The scheduling capabilities of COAST are based on state space exploration of the embedded CPN model. Planners interact with COAST using a domain-specific graphical user interface (GUI) that hides the embedded CPN model and analysis algorithms. This means that COAST is based on a rigorous semantical model, but the use of formal methods is transparent to the users. Trials of operational planning using COAST have been conducted within the Australian Defence Force. The work of Lin Zhang was done while he was with the Command and Control Division of the Australian Defence Science and Technology Organisation.  相似文献   
992.
Denatured and reduced N-terminal extended insulin-like growthfactor-1 (AE-IGF-1) was purified from Escherichia coli extractsand subjected to in vitro folding. The renaturation processwas shown to be a function of the redox potential of the solution.Folding by different methods had no significant effect on therenaturation. A maximal yield of 60% (w/w)was obtained. Thefolded AE-IGF-1 was enzymatically converted to IGF-1. The majorby-product (20% w/w) was identified as scrambled IGF-1. Enzymaticdigestion at alkaline and acidic pH suggested two possible disulphidebond arrangements: (i) Cys6–Cys47, Cys18–Cys61,Cys48–Cys52; or (if) Cys6–Cys52, Cysl8–Cys61,Cys47 and Cys48 being in their reduced forms. Energy minimizationand molecular modelling suggested that the scrambled IGF-1,having reduced cysteines at positions 47 and 48, was the energeticallymost stable conformation of the two.  相似文献   
993.
Improved quality of phase maps in pulsed digital holographic interferometry is demonstrated by finding the right reconstruction distance. The objective is to improve the optical phase information when the object under study is a phase object and when it is out of focus, leading to low contrast fringes in the phase map. A numerical refocusing is performed by introducing an ideal lens as a multiplication by a phase field in the Fourier domain, and then a region of maximum speckle correlation is found by comparing undisturbed and disturbed subimages in different refocused imaging planes. After finding the right reconstruction distance, a phase map of high visibility is constructed. By this technique a 30% reduction of the phase error for a flow of helium gas and a 50% reduction of the phase error for a weak thin lens were obtained, which resulted in a significant improvement of the visual appearance of the phase maps.  相似文献   
994.
In the present work, a direction sensitive bending strain sensor consisting of a single block of epoxy/multi-wall carbon nanotube composite was developed. Moreover, the manufacturing could be realized in a straightforward single-step processing route. The directional sensitivity to bending deformations is related to the change in electrical resistance, which becomes positive or negative, depending on the direction of bending deflection. This effect is achieved by generating a gradient in electrical conductivity throughout the material. The resistance versus strain behaviour of these devices is investigated in detail and related to the microstructure of the nanocomposites.  相似文献   
995.
With decreasing diameter the influence of surface-related effects becomes increasingly important for an understanding of the optical properties of semiconductor nanowires. We present time integrated and time resolved photoluminescence studies of single zincoxide nanowires with different diameters. We analyze the changes in the optical spectra for wires with different surface-to-volume ratios, present optical spectra of single wires at different excitation densities, and study the time-resolved dynamics of the surface related and donor-bound exciton related emission lines for a single nanowire at low temperatures.  相似文献   
996.
997.
Software and Systems Modeling - Declarative process modelling languages focus on describing a process by restrictions over the behaviour, which must be satisfied throughout the whole process...  相似文献   
998.
This study focuses on bicycle-related injuries among young children and the effect of being an inexperienced beginner related to age at debut of cycling. The study was based on a random stratified population sample of 1200 children aged 4-15 years in Bergen, Norway. Data about age at debut of cycling, cycling habits and any previous bicycle-related injuries were collected. A child was defined as a beginner within the first 12 months of active cycling. Relation between the first bicycle-related injury and age at debut was analysed by the Kaplan-Meier method. The risk of getting injured during the first 12 months of active cycling were significant lower for children aged 7 or 8 years at the debut of cycling compared to younger children (hazard ratio = 0.78, P < 0.001). Children cycling more than 1h per week were at greater risk of getting injured during the first 12 months than those who cycled less (hazard ratio = 1.95, P = 0.014). This study shows that the risk of getting injured during the first 12 months of active cycling is reduced if bicycling debut is delayed until 7 or 8 years instead of at 4 or 5 years.  相似文献   
999.
This article starts from the paradox that, although participation is a defining trait of participatory design (PD), there are few explicit discussions in the PD literature of what constitutes participation. Thus, from a point of departure in Actor-Network Theory (ANT), this article develops an analytical understanding of participation. It is argued that participation is a matter of concern, something inherently unsettled, to be investigated and explicated in every design project. Specifically, it is argued that (1) participation is an act overtaken by numerous others, rather than carried out by individuals and (2) that participation partially exists in all elements of a project. These traits are explicated in a design project called ‘Teledialogue’, where the participants are unfolded as networks of reports, government institutions, boyfriends, social workers and so on. The argument is synthesised as three challenges for PD: (1) participants are network configurations, (2) participation is an aspect of all project activities and (3) there is no gold standard for participation.  相似文献   
1000.
The performance of an alternately operated activated sludge wastewater treatment plant (WWTP) has been investigated with respect to six phthalates, nonylphenol (NP) and nonylphenol diethoxylate (NPDE) and linear alkylbenzene sulphonates (LAS). Samples of raw sewage, primary and secondary sludge and treated water were collected during an 8-day period in May 1999 and analysed for dissolved and sorbed substances. To evaluate the system performance with respect to substance removal through biodegradation and sorption to sludge the measured data were applied in a model describing the different bioreactors as one single reactor, corresponding to the concepts of, e.g. SimpleTreat. The most abundant of the investigated phthalates was di-(2-ethylhexyl)-phthalate (DEHP) with a measured mean inlet flow of 240g/day. Two percent of this amount was found in the treated water, 70% was biodegraded and 28% was found in the sludge. For LAS the mean inlet flow was 20,300g/day, of which less than 1% was found in the treated water, 84% was biodegraded and 15% was found in the sludge. The mean inlet flow of NP and NPDE was 44 and 590g/day, of which 4% and 2% was found in the treated water, 80% was biodegraded for both substances, and 16% and 18% was found in the sludge, respectively. The WWTP removal of the investigated substances was thus high compared to other studies of conventional activated sludge WWTPs. The simple model set-up presents a strong tool for predicting substance removal and system sensitivity related to changes in the inlet conditions, such as concentrations and flow. Furthermore, it allows the inclusion of complex alternately operated WWTPs in risk assessment tools such as e.g. SimpleTreat.  相似文献   
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