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1.
A study was conducted at Lake J?ms?nvesi in Central Finland, to identify the potential ecotoxicological risks of the remediation operation of a creosote-/PAH-contaminated lake sediment, made by capping during the years 1998-1999. Mussels (Anodonta anatina) were deployed to the lake at the same time as the remediation operation was started in November 1998. The contaminated area (0.5 ha) was covered by a filter geotextile (polypropylene), gravel and sand (1-1.5m) which were spread out on the ice and let to sink onto the bottom of the lake when the ice melted in May 1999. The possible impacts of capping to the adjacent environment were assessed from mussels exposed and particulate material settled (SPM) to collectors placed on the lake bottom. Mussel tissue, SPM, the water inside the collector were analyzed for polycyclic aromatic compounds (PAH)-compounds. Biological endpoints included body condition, glycogen and protein contents of adductor muscle. Mussels and SPM exposed downstream to the contaminated site (Site 3) contained the highest total PAH concentrations. Biota-sediment accumulation factors of acenaphthene, phenanthrene, anthracene, fluoranthene, pyrene and benzo(a)anthracene of mussels varied from 0.79 to 1.45. The glycogen and protein concentrations were lowest in adductor muscle from mussels exposed to conditions at Site 3. Concentrations of some PAH-compounds were found distinctly increased adjacent to the remediated area, possibly due to the agitation of contaminated sediment due to the capping. It is also possible that resuspension of sediment around remediated area (containing some PAHs) spread the deposited PAH-compounds.  相似文献   
2.
Older adults are becoming an important market segment for all internet-based services, but few studies to date have considered older adults as online shoppers and users of entertainment media. Utilising the concept of life course, this article investigates the use of mobile technologies for online shopping and entertainment among consumers aged 55 to 74. The data were collected with a web-based survey completed by a panel of respondents representing Finnish television viewers (N = 322). The results reveal that consumers aged 55 to 74 use a smartphone or tablet to purchase products or services online as often as younger consumers. In contrast, listening to internet radio and watching videos or programmes online with a smartphone or tablet are most typical for younger male consumers. The results demonstrate that mobile-based online shopping is best predicted by age, higher education, and household type (children living at home), and use of entertainment media by age and gender.  相似文献   
3.
The working of a tool, Simulation Nets, for designing and executing models for simulation of systems is presented. The tool is an extension of the theoretically attractive Petri Nets, whose suitability in general simulation modeling has largely been overlooked in the simulation community. Simulation Nets helps in obtaining a correct simulation model because of their good graphical properties, their strength in describing concurrent processes, and because of the possibility in proving correctness for some parts of the model by applying the well known reachability tree technique. The resulting graphical model consists of a number of submodels. The submodels are exact enough to permit simulation experiments to be performed without the need of programming. This permits easy incremental validation of the model, i.e., validation of the submodels and a hierarchy of coupled submodels. Simulation nets thus facilitates rapid modeling and experimentation and thus supports the decision maker in obtaining the data needed for him to make his decision. Experiences with a working prototype are presented.  相似文献   
4.
An average “real” process is determined from 55 processes automated by an automation system. This a first step in developing realistic benchmark processes for making objective evaluation tests between the performance of different automation systems. The most important properties of the average process that are independent of the automation system used and that are important performance indicators are presented in the paper.The real process, representing the statistical mean of the process data best, is a papermachine with a pulp making department. The process has 141 analog inputs, 50 binary inputs, 90 analog outputs, 63 binary outputs, 77 motor controls, 8 motor value controls, 308 process interfaces, and 165 displays.  相似文献   
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Design guidelines and checklists are suggested as a useful tool in the development and evaluation of interface design of mobile phones for older adults. Given the intense evolution of mobile phone design, understanding how the design guidelines and checklists have taken into account the advances in mobile phone usability for older adults is important for their correct application and future development. Thus, this study explores the usability dimensions of mobile phone design for older adults and the related changes in terms of time and the type of device (feature phones vs. smartphones) based on an expert coding of the eight mobile phone design guidelines and checklists for older adults published between 2006 and 2014. The results of the expert coding show that design guidelines and checklists most frequently deal with visual and haptic issues (e.g., high contrast, button type, and button size), whilst they hardly ever address various elements of textual interface (e.g., ease of text entry, a button’s feedback, and font type). Over time, the design guidelines and checklists have become more complex in terms of the average number of included usability categories and dimensions. For smartphones, the guidelines, on average, put more emphasis on the screen, touchscreen, text, and exterior related issues, whereas the design guidelines for feature phones stress the usability of the keypad and menus. Besides revealing potential usability dimensions that could be further expanded in the guidelines, this study also highlights the need for research that would empirically validate the design guidelines and checklists in the future.  相似文献   
7.
We have been studying seasonal variations in soil gas radon concentration in southern Finland since 1982.To detect the radon we employ liquid scintillation solution in an open glass vial placed in a plastic tube set in a hole drilled in the ground.The results from an esker area show that there may be an appreciable seasonal variation in soil gas radon concentration, similar to that in houses. Because of the varying permeability and radium concentration of the ground, small changes in the building may have a large impact.  相似文献   
8.
Code division multiple access and many other applications require large families of sequences with good correlation properties. In this paper we show that the moduli of certain character sums can be estimated in an easy way by using a method of Sidelnikov. These results yield a simple method to estimate the maximum nontrivial correlations of several well-known sets of sequences.Supported by the Technology Development Center of Finland, Elektrobit Company, Finnish Air Force, Nokia Mobile Phones Inc. and Nokia Cellular Systems Inc.Partially supported by the Academy of Finland  相似文献   
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Häkkinen J  Oikari A 《Water research》2004,38(12):2891-2897
There is a considerable lack of in situ specific information about the effects of UV-B radiation on limnic animals studied in the field. We exposed larval pike (Esox lucius L.) in two types of cuvettes (glass and quartz) placed at different depths (5 or 15 cm) to natural solar UV or to artificially enhanced UV-B (lamps on 3 h per day), simulating the scenarios for coming decades. Dose realism and comparability with earlier laboratory experiments was the main purpose, and therefore UV-B irradiances to the surface as well as underwater irradiances were directly measured. Result showed that UV-B dose rates in natural waters are low even though DOC concentration was low (4.8 mg/l) in our study lake. A slight increase in ambient UV-B dose rates was enough to cause neurobehavioral symptoms in pike larvae. However, the dose rates applied were inadequate to affect superoxide dismutase (SOD) or HSP70. While assessing the suggested risks due to increased UV, conclusions emphasize the importance of conducting field UV studies as supplements to laboratory experiments. We also recommend direct measurements of UV-radiation at sites where the target organisms are actually exposed.  相似文献   
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