Search results for "liikenne"
showing 10 items of 160 documents
Multi-Connectivity in 5G and Beyond Non-Terrestrial Networks
2022
The Fifth Generation (5G) communications systems aim to serve such service classes as Ultra-Reliable Low Latency Communications (URLLC), enhanced Mobile Broadband (eMBB), and massive Machine-Type Communications (mMTC). To meet the growing requirements posed to mobile networks, satellites can be used to complement the Terrestrial Networks (TNs). To increase the efficiency of the satellite communications involved, bandwidth-efficient techniques should be used. Multi- Connectivity (MC) is one such technique. In MC, a User Equipment (UE), for example, a smartphone, can be connected to multiple Next Generation Node Bs (gNBs) simultaneously. In this paper, an adaptive MC activation scheme for thr…
Performance enhancements of MBMS and VoIP services in WCDMA/HSPA networks
2009
Naturalistic study on the usage of smartphone applications among Finnish drivers
2018
We present results from a naturalistic study that tracked how Finnish drivers use their smartphones while on the move. We monitored 30 heavy in-car smartphone users in Finland during June–September 2016, recording the times that they used their phones, the application used at the time of touch (calls excluded), the location and driving speed. Touches per time unit were used as a proxy for estimating visual-manual distraction due to visual-manual tasks. Our data set allows the determining of whether drivers use their phones differently on varying road types (highway, main road, local rural road, urban road). We found that the road type has an effect on phone use but the effect is contrary to…
Sleep and sleepiness in shift-working tram drivers
2020
Driver sleepiness contributes to traffic accidents. However, sleepiness in urban public transport remains an understudied subject. To fill this gap, we examined the sleepiness, sleep, and on-duty sleepiness countermeasures (SCMs) in 23 tram drivers working morning, day, and evening shifts for three weeks. Sleepiness was measured using Karolinska Sleepiness Scale (KSS). Nocturnal total sleep time (TST) was measured with wrist actigraphy. SCMs and naps were self-reported with a smartphone application. Caffeine and napping were considered effective SCMs. Severe sleepiness (KSS >= 7) was observed in 22% of shifts with no differences between shift types. Rest breaks were associated with slight r…
The emission reduction potential of electric transport modes in Finland
2021
The transportation sector has become the fastest growing source of greenhouse gas (GHG) emissions. One solution to mitigate the impacts is a shift towards electric modes. Where previous studies have only focused on the replacement of individual modes, our study presents a more holistic approach by comparing land-based, water-based and airborne transportation modes. We study the GHG emission reduction potentials of electric cars, buses, trains, ferries and aircraft in comparison to existing modes on 34 routes within Finland and across the Baltic Sea to Sweden and Estonia. By comparing the GHG emissions in carbon dioxide equivalents (CO2-eq) per passenger kilometer for each mode, we also cons…
Performance evaluation of OpenFlow enabled Commodity and Raspberry-pi Wireless Routers
2017
Software defined network (SDN) allows the decoupling of data and control plane for dynamic and scalable network management. SDN is usually associated with OpenFlow protocol which is a standard interface that enables the network controllers to determine the path of network packets across a network of switches. In this paper, we evaluate openflow performance using commodity wireless router and raspberry pi with two different SDN controllers. Our test setup consists of wired and wireless client devices connected to openflow enabled commodity wireless router and raspberry pi. All clients used traffic generator tool to transmits data to a sink server host. The results are promising and paves the…
Vehicles, replicators, and intercellular movement of genetic information: evolutionary dissection of a bacterial cell.
2012
Prokaryotic biosphere is vastly diverse in many respects. Any given bacterial cell may harbor in different combinations viruses, plasmids, transposons, and other genetic elements along with their chromosome(s). These agents interact in complex environments in various ways causing multitude of phenotypic effects on their hosting cells. In this discussion I perform a dissection for a bacterial cell in order to simplify the diversity into components that may help approach the ocean of details in evolving microbial worlds. The cell itself is separated from all the genetic replicators that use the cell vehicle for preservation and propagation. I introduce a classification that groups different r…
Elaboration of NMT and GSM standards : from idea to market
2002
The focus of this study is on elaboration of NMT (Nordic Mobile Telephone) and GSM (Global System for Mobile communications) standards. It seeks to understand the standard-making process from a system's philosophy to market entry.The specific objectives of the study are 1) to reconstruct the original ideas of innovation, 2) to reconstruct standardization processes of NMT and GSM systems, 3) to reconstruct interplay and impact of key players during standardization process, and 4) to explain success of NMT and GSM standards. Analyzing processes of two successful mobile communication standard-making aims to reveal what were the specific Nordic standardization practices and principles, and what…