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An efficient cluster-based outdoor user positioning using LTE and WLAN signal strengths
2015
In this paper we propose a novel cluster-based RF fingerprinting method for outdoor user-equipment (UE) positioning using both LTE and WLAN signals. It uses a simple cost effective agglomerative hierarchical clustering with Davies-Bouldin criterion to select the optimal cluster number. The positioning method does not require training signature formation prior to UE position estimation phase. It is capable of reducing the search space for clustering operation by using LTE cell-ID searching criteria. This enables the method to estimate UE positioning in short time with less computational expense. To validate the cluster-based positioning real-time field measurements were collected using readi…
LOCAL CONTROL OF SOUND IN STOCHASTIC DOMAINS BASED ON FINITE ELEMENT MODELS
2011
A numerical method for optimizing the local control of sound in a stochastic domain is developed. A three-dimensional enclosed acoustic space, for example, a cabin with acoustic actuators in given locations is modeled using the finite element method in the frequency domain. The optimal local noise control signals minimizing the least square of the pressure field in the silent region are given by the solution of a quadratic optimization problem. The developed method computes a robust local noise control in the presence of randomly varying parameters such as variations in the acoustic space. Numerical examples consider the noise experienced by a vehicle driver with a varying posture. In a mod…
Transformation of the Forest-based Bioeconomy by Embracing Digital Solutions
2017
This paper attempts to explore a new insight to both industrialized and growing economies by demonstrating a digital-driven creative disruption in the forest-based bioeconomy which is beginning to replace its conventional and narrow concept of a forest-blinded economy. Notwithstanding the potential broad cross-sectoral benefits to both industrialized and growing economies, natural environments and locality constraints and the incessant challenge of distance have impeded balanced development of this economy. However, driven by digital solutions the economy has taken big steps forward in recent years. Digitalization has enabled real-time end-to-end supply chain visibility, improved delivery a…
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 …
Isophorone on Au/MgO/Ag(001) : Physisorption with Electrostatic Site Selection
2017
We report a computational study of isophorone C9H14O adsorption on a Ag(001)-supported ultrathin MgO film with Au adatoms and clusters employing density functional theory calculations. The calculations show that the keto form of isophorone is more stable than the enol tautomers both in gas phase and on the MgO/Ag(001) surface. The interaction between the keto isophorone and step and terrace sites of MgO/Ag(001) displays long interaction distances, relatively weakly exothermic adsorption energies, lack of charge transfer, and minor changes in the density of states, all of which indicate that the molecule merely physisorbs on the surface. The step sites are energetically preferred adsorption …
Molecule-like photodynamics of Au102(pMBA)44 nanocluster.
2015
Photophysical properties of a water-soluble cluster Au102(pMBA)44 (pMBA = para-mercaptobenzoic acid) are studied by ultrafast time-resolved mid-IR spectroscopy and density functional theory calculations in order to distinguish between molecular and metallic behavior. In the mid-IR transient absorption studies, visible or near-infrared light is used to electronically excite the sample, and the subsequent relaxation is monitored by studying the transient absorption of a vibrational mode in the ligands. Based on these studies, a complete picture of energy relaxation dynamics is obtained: (1) 0.5-1.5 ps electronic relaxation, (2) 6.8 ps vibrational cooling, (3) intersystem crossing from the low…
Multicriteria evaluation of alternatives for remote monitoring systems of municipal buildings
2014
Abstract Conservation of natural resources drives municipalities to monitor their heat, power and water consumption more accurately. The objective of this study was to evaluate different implementation possibilities for remote monitoring systems for the municipal buildings of two medium-sized municipalities, Hollola and Nastola in Southern Finland. Four different alternatives were considered: (1) a system by an external service provider, (2) a system provided by the local energy distribution company, (3) a system built by the municipalities themselves, and (4) using the current manual system but with more frequent data collection. The alternatives were evaluated in terms of multiple functio…
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…
How news affect the trading behavior of different categories of investors in a financial market
2015
We investigate the trading behavior of a large set of single investors trading the highly liquid Nokia stock over the period 2003-2008 with the aim of determining the relative role of endogenous and exogenous factors that may affect their behavior. As endogenous factors we consider returns and volatility, whereas the exogenous factors we use are the total daily number of news and a semantic variable based on a sentiment analysis of news. Linear regression and partial correlation analysis of data show that different categories of investors are differently correlated to these factors. Governmental and non profit organizations are weakly sensitive to news and returns or volatility, and, typica…
Vapaapalokunta - kasvupaikka kansalaistoiminnalle 1838-1938
2011
Vapaapalokuntatoiminta alkoi maassamme vuonna 1838 naapurimaista saadun esimerkin mukaisesti. VPK:iden toiminta muotoutui moninaiseksi ja se oli tarkoitettu kaikille kansalaisille. Toiminnassa noudatettiin tasa-arvon ja demokratian periaatteita alusta lähtien ja toiminnan tavoitteisiin kuuluivat yleishyödyllisyys sekä luokkaerojen vähentäminen jäsenten keskuudessa amerikkalaisen esikuvansa mukaisesti. Tutkielman tarkoituksena on selvittää vapaapalokuntatoiminnan merkitystä kansalaisyhteiskunnalle ja kansalaisille niillä paikkakunnilla, joilla yhdistyksiä perustettiin. Tutkielman ajaksi olen rajannut ensimmäisen sadan vuoden ajan, koska silloin vapaapalokuntatoiminta oli aitoa vapaaehtoista …