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81.
MundoCore is a communication middleware specifically designed for the requirements of pervasive computing. To address the high degree of heterogeneity of platforms and networking technologies, it is based on a microkernel design, supports dynamic reconfiguration, and provides a common set of APIs for different programming languages (Java, C++, Python) on a wide range of different devices. The architectural model addresses the need for proper language bindings, different communication abstractions, peer-to-peer overlays, different transport protocols, different invocation protocols, and automatic peer discovery. 相似文献
82.
Elimination of microcystins by water treatment processes-examples from Sulejow Reservoir, Poland 总被引:1,自引:0,他引:1
Jurczak T Tarczynska M Izydorczyk K Mankiewicz J Zalewski M Meriluoto J 《Water research》2005,39(11):2394-2406
Eutrophication is a serious problem in Polish freshwaters. Mass occurrences of toxic cyanobacteria in reservoirs cause problems in the production of safe drinking water and the diversity of produced toxins complicates monitoring of freshwaters. The aim of this study was to estimate the efficiency of water treatment processes in the removal of microcystins (MCs), cyanobacterial hepatotoxins. Elimination of microcystins was studied at two waterworks, which supply drinking water to the city of Lodz from Sulejow Reservoir. The consecutive steps of pre-oxidation, coagulation, sand filtration, ozonation and chlorination used in the water treatment showed effective elimination of microcystins in water from Sulejow Reservoir in 2002 and 2003. The highest total concentration of microcystin (variants MC-RR, MC-YR, MC-LR) amounted to 6.7 microgl(-1) in raw water and was detected on the 13th of August 2002. In 2003 the water utility decided to increase the contribution of ground water in the production of drinking water. This resulted in a decrease of microcystin in water during and after the treatment process. The current management strategy of the waterworks company includes mixing of surface water and ground water, which reduces the hazards caused by toxic cyanobacterial blooms in the reservoir. 相似文献
83.
Basunia MS Landsberger S Yli-Tuomi T Hopke PK Wishinski P Paatero J Viisanen Y 《Environmental science & technology》2003,37(24):5537-5544
Mean silver concentrations in weekly particle samples collected at Kevo, northern Finland, were determined for the period of October 1964-March 1978 by neutron activation analysis. Two distinct periods were observed in the silver concentration levels over this time frame. During 1964-1970, mean weekly silver concentration levels were found in the range of 0.01-190 ng/m3 with an arithmetic mean of 2.19 ng/m3. A few very high silver concentration levels (>10 ng/m3) were observed in this period, some of which simultaneously occurred with some of the highest bromine and iodine concentration levels. During 1971-1978, silver concentration levels were in the range of 0.02-0.89 ng/m3 with a mean value of 0.09 ng/m3. The observed concentration levels in the later period matched well the data from the early 1990s reported at Sevettij?rvi, northern Finland, about 60 km east of Kevo. Data analysis, historical records for this region, and residence time analysis (RTA) using wind back-trajectories show that occasional smelting of silver-rich Norilsk ores at the Nikel smelter, Kola Peninsula, was probably a significant contributor to elevated mean silver concentration levels during 1964-1970. RTA alone was not able to unambiguously identify the most probable source region for highest silver impacts at Kevo due to the weekly integrated nature of the samples collected. Critical examination of wind back-trajectories (24 per day) for specific high silver, bromine, and iodine concentration weeks was carried out to supplement the ensemble RTA analysis (2 back-trajectories per day). The supplemental back-trajectory analysis revealed that deposition of the smelter component silver as well as the sea components (bromine and iodine) could occur together at Kevo during these weekly sampling periods. The study implies that data from weekly integrated samples are insufficiently time-resolved for RTA methods alone to unambiguously resolve the sources contributing to ambient atmospheric concentrations at Kevo, Finland. 相似文献
84.
The sorption and desorption of two model compounds, benzo[a]pyrene (BaP) and 3,4,3',4'-tetrachlorobiphenyl (TCBP), were studied in natural lake water with high dissolved organic matter (DOM) content using the equilibrium dialysis and Tenax extraction methods. The sorption of TCBP was lower and reached steady value more slowly than did BaP. Tenax extraction revealed at least two differently desorbing fractions for both model compounds, which also supported the conclusion that DOM-HOC associations may involve several mechanisms. The rapidly desorbing fraction may be attributed to freely dissolved and loosely sorbed compound, whereas the more strongly sorbed fraction may indicate the presence of specific binding sites. The data indicated that the association between hydrophobic organic contaminants (HOC) and DOM is not simply absorption that is solely driven by the lipophilicity of the sorbates. Although contact time had a rather negligible effect on the sorption of BaP, the proportion of desorption resistant fraction increased with time, whereas the desorption of TCBP was less affected by contact time. Steric factors may be the cause of the lower sorption and smaller desorption resistant fraction of TCBP. The results indicate potential differences in the behavior of PAHs and PCBs in the aquatic environment. 相似文献
85.
Mykkänen J Tohka J Luoma J Ruotsalainen U 《Computer methods and programs in biomedicine》2005,79(1):1-17
In this study, we propose and evaluate new methods for automatic extraction of the brain surface and the mid-sagittal plane from functional positron emission tomography (PET) images. Designing methods for these segmentation tasks is challenging because the spatial distribution of intensity values in a PET image depends on the applied radiopharmaceutical and the contrast to noise ratio in a PET image is typically low. We extracted the brain surface with a deformable model which is based on a global optimization algorithm. The global optimization allows reliable automation of the extraction task. Based on the extracted brain surface, the mid-sagittal plane was determined. The method was tested with the image of the Hoffman brain phantom (FDG) and the images from the brain studies with the FDG (17 images) and the C11-Raclopride tracers (4 images). In addition to the brain surfaces, we applied the deformable model for extraction of the coarse cortical structure based on the tracer uptake from FDG-PET brain images. The proposed segmentation methods provide a promising direction for automatic processing and analysis of PET brain images. 相似文献
86.
Tuija Jetsu Yasser Essiarab Ville Heikkinen Timo Jaaskelainen Jussi Parkkinen 《Color research and application》2011,36(4):266-271
According to recent physiological research results, there are many individual differences already at the detection level of our color vision system. It is not completely clear yet, how the other levels of color vision system compensate the detection differences. Instead of detecting and analyzing colors exactly in the same way, we all just have learned to classify colors in a certain way, which seems to lead almost always to the same result independent of the individual differences in the color vision system. In this article, we experiment with four models developed for replicating certain properties of human color vision. We examine the color classification abilities of these models and show the differences and similarities in their behavior. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010. 相似文献
87.
88.
The physical adaptability of buildings is very important in today's fast-changing business environment. The actors who invest in long-term adaptability are positioned better to the changes during the life cycle of a building. This conceptual paper argues that the current dominating real estate (property) investment analysis theories do not accommodate enough building design-related information (i.e. physical asset characteristics), which results in long-term loss of competitiveness and unsustainable use of built environment resources. It is demonstrated that physical asset characteristics can create valuable real options that should be acknowledged in real estate investment analysis and management. The real estate investment literature has not so far been able to produce a widely accepted financial model for justifying life-cycle investments. A theory is proposed here that can be used to value life-cycle investments in buildings. This new theory combines of real options valuation, investment analysis and building component life-cycle design. These themes are used to formulate a conceptual framework for valuing life-cycle investments. The framework is intuitive and transparent, and it can be easily added to current spreadsheet investment analysis tools. 相似文献
89.
Jarno Einolander Hannu Vanharanta Yoon Seok Chang Jussi Kantola 《Theoretical Issues in Ergonomics Science》2016,17(3):267-283
The aim of this research was to evaluate and compare the creative tension of university students in three different universities in South Korea and Finland. The creative tension, or the gap between a person's feeling of current reality and target for future, was analysed according to features describing their committing factors related to their universities and studies. Data for this study were collected from 41 university students through self-evaluation using internet-based survey instrument. The application was able to identify the creative tension in each group of university students, and the results show differences in creative tension across the universities and also between countries. This type of in-depth analysis into the cultural perceptions of attributes offers valuable new information for academia and businesses. 相似文献
90.