Search results for "Invention."
showing 10 items of 12465 documents
Cluster-Based RF Fingerprint Positioning Using LTE and WLAN Outdoor Signals
2015
In this paper we evaluate user-equipment (UE) positioning performance of three cluster-based RF fingerprinting methods using LTE and WLAN signals. Real-life LTE and WLAN data were collected for the evaluation purpose using consumer cellular-mobile handset utilizing ‘Nemo Handy’ drive test software tool. Test results of cluster-based methods were compared to the conventional grid-based RF fingerprinting. The cluster-based methods do not require grid-cell layout and training signature formation as compared to the gridbased method. They utilize LTE cell-ID searching technique to reduce the search space for clustering operation. Thus UE position estimation is done in short time with less comput…
Visualization in the integrated SimPhoNy multiscale simulation framework
2018
Abstract We describe three distinct approaches to visualization for multiscale materials modelling research. These have been developed with the framework of the SimPhoNy FP7 EU-project, and complement each other in their requirements and possibilities. All have been integrated via wrappers to one or more of the simulation approaches within the SimPhoNy project. In this manuscript we describe and contrast their features. Together they cover visualization needs from electronic to macroscopic scales and are suited to simulations made on personal computers, workstations or advanced High Performance parallel computers. Examples as well as recommendations for future calculations are presented.
On optimal relay placement for improved performance in non-coverage limited scenarios
2014
Low power nodes have been a hot topic in research, standardization, and industry communities, which is typically considered under an umbrella term called heterogeneous networking. In this paper we look at the problem of deploying optimally low power nodes in the context of relay networking, when an operator connects low power nodes (or small cells) via the wireless backhaul that uses the same spectrum and the same wireless access technology. We present an analytical model that can calculate optimal coordinates for low power nodes based on the input parameters, such as preferred number of nodes, their transmission power, parameters of the environment etc. The analytical calculations are comp…
Effects of Temperature and Humidity on Radio Signal Strength in Outdoor Wireless Sensor Networks
2015
Many wireless sensor networks operating outdoors are exposed to changing weather conditions, which may cause severe degradation in system performance. Therefore, it is essential to explore the factors affecting radio link quality in order to mitigate their impact and to adapt to varying conditions. In this paper, we study the effects of temperature and humidity on radio signal strength in outdoor wireless sensor networks. Experimental measurements were performed using Atmel ZigBit 2.4GHz wireless modules, both in summer and wintertime. We employed all the radio channels specified by IEEE 802.15.4 for 2.4GHz ISM frequency band with two transmit power levels. The results show that changes in …
Detecting explosive substances by the IR spectrography
2014
Fast and safe detection methods of explosive substances are needed both before and after actualized explosions. This article presents an experiment of the detection of three selected explosives by the ATR FTIR spectrometer and by three different IR hyperspectral imaging devices. The IR spectrometers give accurate analyzing results, whereas hyperspectral imagers can detect and analyze desired samples without touching the unidentified target at all. In the controlled explosion experiment TNT, dynamite and PENO were at first analyzed as pure substances with the ATR FTIR spectrometer and with VNIR, SWIR and MWIR cameras. After three controlled explosions also the residues of TNT, dynamite and P…
Jahn–Teller effects in Au25(SR)18
2016
The relationship between oxidation state, structure, and magnetism in many molecules is well described by first-order Jahn–Teller distortions. This relationship is not yet well defined for ligated nanoclusters and nanoparticles, especially the nano-technologically relevant gold-thiolate protected metal clusters. Here we interrogate the relationships between structure, magnetism, and oxidation state for the three stable oxidation states, −1, 0 and +1 of the thiolate protected nanocluster Au25(SR)18. We present the single crystal X-ray structures of the previously undetermined charge state Au25(SR)18+1, as well as a higher quality single crystal structure of the neutral compound Au25(SR)180. …
Performance of an asymmetric and asynchronous decode-and-forward FBMC relay system
2014
End-to-end link performance of an asymmetric and asynchronous dual-hop decode-and-forward (DF) relay system built up using a causal multirate filter bank multicarrier (FBMC) technique operated under Rayleigh fading is presented. Three main performance measures namely bit error rate (BER), outage probability and channel capacity are used for this evaluation and approximate closed-form expressions for them are also made available. FBMC setup is modeled in exact form without any approximations while customizing to one of the most efficient subcarrier filter. Simulations are carried out in quasi-static multipath fading channels under symmetric, asymmetric, synchronous and asynchronous condition…
Iron and pH regulating the photochemical mineralization of dissolved organic carbon
2017
Solar radiation mineralizes dissolved organic matter (DOM) to dissolved inorganic carbon through photochemical reactions (DIC photoproduction) that are influenced by iron (Fe) and pH. This study addressed as to what extent Fe contributes to the optical properties of the chromophoric DOM (CDOM) and DIC photoproduction at different pH values. We created the associations of Fe and DOM (Fe-DOM) that cover the range of loadings of Fe on DOM and pH values found in freshwaters. The introduced Fe enhanced the light absorption by CDOM independent of pH. Simulated solar irradiation decreased the light absorption by CDOM (i.e., caused photobleaching). Fe raised the rate of photobleaching and steepened…
Contributions to risk injury evaluation of human skin contact caused by welding technology in mechanical engineering a company
2017
Assembly by welding is a very important pollutant technological process, mainly of the atmosphere and soil. The formation of gas in welding process is the result of electrodes, fluxes burning, formation of fused bath and welded seam. A large number of human operators feels different adverse effects on health. Most problems appears in respiratory system and include bronchitis, respiratory irritation, fever caused by smoke, changes in lung function, decreased immunity to infection and a possible increase of lung cancer risk. Very little information are available about effects on the organism and skin after exposure to fumes from welding, therefore. In this order, this paper do a risk assessme…
Effect of oil lamination between plasticized starch layers on film properties
2016
International audience; To reduce the hygroscopic character of biodegradable starch-based films, rapeseed oil was incorporated by lamination (starch-oil-starch 3-layers technique). The lipid lamination followed by starch solution casting step induced an emulsion type structure of dried films. Composite films are more opalescent and glossier than fatty free starch films. For all the films, structure is heterogeneous in the cross-section only. Adding fat induced a twice decrease of the tensile strength. Thermal gravimetry analysis did not show differences between films with and without oil. Lipid reduced the moisture absorption particularly at higher RH as well as the surface swelling index, …