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401.
Ali?HarlinEmail author Pertti?Nousiainen Arja?Puolakka Jani?Pelto Juha?Sarlin 《Journal of Materials Science》2005,40(20):5365-5371
Conducting polyester PET and polyamide PA-6 fibre and fabrics were prepared by in-situ chemical oxidative polymerisation using super critical fluid assisted process. The fibre materials and cloths produced were
characterized by means of FTIR, WAXD, SEM, and DSC and two-probe resistivity. The samples were studied also by means of washing
them several times. Homogeneous treated fibre materials with sustainable properties were produced. Melt spun fibre material
of inherently conducting polymer blends have been reported earlier. Reasonable mechanical and electrical properties (resistance
of 105…107 Ω/cm) are typical for blend of polypropylene and polyaniline. With bi-component extrusion technology the fibre as good as
103…105 Ω/cm is reachable. 相似文献
402.
403.
The evolution of perspective view in WalkMap 总被引:1,自引:0,他引:1
Riku?SuomelaEmail author Kimmo?Roimela Juha?Lehikoinen 《Personal and Ubiquitous Computing》2003,7(5):249-262
A wearable computer is a potential platform for map applications: it is mobile in nature, and is often equipped with a head-worn display capable of displaying maps of the surrounding area in graphical form. In this paper, we present a map application, called WalkMap, developed for wearable computers. We concentrate on the visual presentation of the map, and propose a visualisation method that is based on the perspective distortion of a regular two-dimensional bird's-eye view map. We also describe the results of a field study, and compare the distorted view to a regular two-dimensional view. The results show that while a perspective visualisation is good for some navigational tasks, for some other tasks a regular map is preferred. We then continue by developing the visualisation further, and present a fully adjustable three-dimensional version of the map application, called WalkMap3D. WalkMap3D can display the map area in three dimensions, but is also capable of displaying both traditional two-dimensional and perspective map views.Abbreviations GLU OpenGL Graphics System Utility Library - HWD Head Worn Display - LOD Level of Detail - VRML Virtual Reality Modelling Language - YAH You Are Here 相似文献
404.
Pn Photodiodes for Pulsed Laser Rangefinding Applications Realized in Standard CMOS/BiCMOS Processes
Pasi Palojärvi Tarmo Ruotsalainen Juha Kostamovaara 《Analog Integrated Circuits and Signal Processing》2001,27(3):237-246
This paper describes simulation of theoperation of integrated high-speed
photodiodes and verification of the results bymeans of measurements performed with two typesof photodiode, one implemented in a standard 0.8m CMOS process and the other in a standard1.2 m BiCMOS process. The measured rise timesand responsivities of the photodiodes were <5ns and 0.28 A/W in the CMOS process and 30 ns and0.31 A/W in the BiCMOS process. Furthermore, thesuitability of the photodiode for 3D vision wasinvestigated by designing an array ofphotodetectors and measuring the isolationbetween the detector blocks. The results confirmthat the photodetectors and receiver for a pulsedlaser rangefinder can be implemented on the samechip in a standard process without any processmodifications. 相似文献
405.
406.
Michael Sivak Michael Flannagan Andrew W. Gellatly Juha Luoma 《Color research and application》1992,17(5):356-360
High-intensity-discharge (HID) headlamps, in comparison to tungsten–halogen headlamps, emit proportionally less energy in the long-wavelength end of the visible spectrum—precisely in the region where retroreflective red stop signs are most reflective. A likely consequence of the use of HID headlamps is a colorimetric shift of stop signs. This study was designed to examine the consequences of colorimetric shifts of red sign materials in different colorimetric directions. Subjects were shown individual small color samples under controlled lighting conditions. Their task was to indicate, on each trial, whether the sample color was acceptable for stop signs. At the end of each experimental session, subjects were asked to select a single most appropriate color for stop signs from among 16 simultaneously presented color samples. There are two main findings. First, there is an overwhelming agreement among observers concerning the most appropriate red color for stop signs out of the 16 colors presented. Second, observers were relatively sensitive to hue shifts towards orange, while relatively insensitive to saturation shifts towards pink. Consequently, designers of HID headlamps should try to minimize the extent of colorimetric shifts of red sign materials towards orange. 相似文献
407.
Antti Tarkiainen Riku Pöllänen Markku Niemelä Juha Pyrhönen 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,88(2):97-107
A line converter equipped with an LCL-line filter is used as an active filter directly compensating grid voltage harmonics.
The control of four individual grid voltage harmonics is implemented using an individual control of corresponding harmonic
line currents. The knowledge of the grid impedance is essential to efficient control of the grid voltage harmonics. To overcome
the problem of an unknown grid impedance an identification method is used. The method uses the converter control system to
measure the grid impedance at selected frequencies. The active voltage harmonic cancellation is tested with a 19 kVA line
converter by compensating background voltage distortion and distortion caused by a nonlinear load. 相似文献
408.
Petteri Alahuhta Henri Löthman Heli Helaakoski Arto Koskela Juha Röning 《Personal and Ubiquitous Computing》2007,11(1):1-10
The trend of increasing mobile services has set a new challenge for service providers: how to develop more advanced and user-friendly, context-aware and personalized mobile services for the users. Apricot Agent Platform is an agent-based software platform designed for developing context-aware and personalized mobile services. Apricot Agent Platform supports the development of user-friendly mobile services by providing tools for combining various mobile and Internet-based services. Apricot agent architecture consists of an agent platform, agents and agent containers. For the developers of mobile services, it provides built-in functionality and communication mechanism. Furthermore, this paper describes four demonstrators that are built up on the Apricot Agent Platform to evaluate the usability and efficiency of the platform in the processes of building mobile services. The outcome of the evaluation indicates relatively promising results and the further target for development is revealed. 相似文献
409.
This review discusses the developments in aerosol instrumentation that have led to the current vapor condensation based instruments capable of detecting sub-3?nm particles. We begin from selected reports prior to the year 1991, which have advanced the technology or understanding in condensation particle counting toward sub-3?nm sizes, and continue to more in depth review of the past efforts after 1991. We discuss how the developments in the calibration methods have progressed the development of particle counting techniques, and review briefly the sub-3?nm calibration experiments and cluster production methods used in calibration experiments. Based on these reviews, we identify several technological and scientific advances for the future to improve the accuracy, understanding, and technology of sub-3?nm particle counting.Copyright © 2019 American Association for Aerosol Research 相似文献
410.
Purmonen M Valjakka J Takkinen K Laitinen T Rouvinen J 《Protein engineering, design & selection : PEDS》2007,20(11):551-559
Twelve members of the family 11 xylanases, including both mesophilic and thermophilic proteins, were studied using molecular dynamics (MD). Simulations of xylanases were carried out in an explicit water environment at four different temperatures, 300, 400, 500 and 600 K. A difference in thermotolerance between mesophilic and thermophilic xylanases became clear: thermophilic xylanases endured heat in higher simulation temperatures better than mesophilic ones. The unfolding pathways seemed to be similar for all simulations regardless of the protein. The unfolding initiates at the N-terminal region or alternatively from the alpha-helix region and proceeds to the 'finger region'. Unfolding of these regions led to denaturated structures within the 4.5 ns simulation at 600 K. The results are in agreement with experimental mutant studies. The results show clearly that the stability of the protein is not evenly distributed over the whole structure. The MD analysis suggests regions in the protein structure which are more unstable and thus potential targets for mutation experiments to improve thermostability. 相似文献