Value creation in electric vehicle charging networks

Electric vehicles (EV) are gaining a prominent share of the trillion-dollar automotive market. The growth is fueled by falling battery prices, tightening emission standards, government subsidies and increasing competition. The rise of EV’s creates a need for, and also depends on, charging infrastructure on a large scale. Electric vehicle charging networks are services that are used to manage and enable access to charging points. This study aims to understand how these networks can succeed in the tightening competition by examining what factors contribute to the value of an EV charging network for its participants. To reach this goal an explanatory single case study was conducted. The case examined a public EV charging network in Finland. First, earlier research in platform economics and EV charging were used to understand the context and to synthesize a theoretical framework. Next, empirical data was collected primarily with semi-structured interviews. Finally, pattern matching was used to analyze the data. Based on the results, the EV charging industry is still its infancy. EV charging networks mediate transactions between EV drivers and charging point owners (CPO), enabling exchange of information, control of charging points, and payments. Various signals suggest an expansion towards the energy system, as EV charging networks are likely to start aggregating and mediating vehicle-to-grid (V2G) services between EV drivers and energy market agents. The results suggest two focus areas as key factors creating value for participants. Firstly, the main contributor to the success of an EV charging network is the amount of charging points connected to it. This is mainly due to EV drivers’ strong positive cross-side network effects and to CPOs’ strong positive same-side network effects. Secondly, an EV charging network’s boundary resources should be designed to maximize efficiency for both sides. For EV drivers, charging is a mundane task that needs to be as effortless as possible. For CPO’s, offering charging is not a main business, but a relatively small value-added service. This study serves as a starting point for a new research stream, converging EV charging with platform economics research. In addition, the results help researchers in understanding the state of the industry and network operators in making strategic decisions

DNA origami structures as calibration standards for nanometrology

Peer reviewe

Compositional association of 24-h movement behavior with incident major adverse cardiac events and all-cause mortality

Cardiovascular disease (CVD) causes a high disease burden. Physical activity (PA) reduces CVD morbidity and mortality. We aimed to determine the relationship between the composition of moderate-to-vigorous PA (MVPA), light PA (LPA), sedentary behavior (SB), and sleep during midlife to the incidence of major adverse cardiac events (MACE) and all-cause mortality at a 7-year follow-up. The study population consisted of Northern Finland Birth Cohort 1966 members who participated in the 46-year follow-up in 2012 and were free of MACE (N = 4147). Time spent in MVPA, LPA, and SB was determined from accelerometer data. Sleep time was self-reported. Hospital visits and deaths were obtained from national registers. Participants were followed until December 31, 2019, or first MACE occurrence (acute myocardial infarction, unstable angina pectoris, stroke, hospitalization due to heart failure, or death due to CVD), death from another cause, or censoring. Cox proportional hazards model was used to estimate hazard ratios of MACE incidence and all-cause mortality. Isotemporal time reallocations were used to demonstrate the dose–response association between time spent in behaviors and outcome. The 24-h time composition was significantly associated with incident MACE and all-cause mortality. More time in MVPA relative to other behaviors was associated with a lower risk of events. Isotemporal time reallocations indicated that the greatest risk reduction occurred when MVPA replaced sleep. Higher MVPA associates with a reduced risk of incident MACE and all-cause mortality after accounting for the 24-h movement composition and confounders. Regular engagement in MVPA should be encouraged in midlife

Health behaviour and health among North Karelian adult population, spring 2000

CINDI = Countrywide Integrated Noncommunicable Disease Intervention Programme of the WH

Accelerometer-measured physical activity is associated with knee breadth in middle-aged Finns - a population-based study

Background: Articular surface size is traditionally considered to be a relatively stable trait throughout adulthood. Increased joint size reduces bone and cartilage tissue strains. Although physical activity (PA) has a clear association with diaphyseal morphology, the association between PA and articular surface size is yet to be confirmed. This cross-sectional study aimed to clarify the role of moderate-to-vigorous PA (MVPA) in knee morphology in terms of tibiofemoral joint size. Methods: A sample of 1508 individuals from the population-based Northern Finland Birth Cohort 1966 was used. At the age of 46, wrist-worn accelerometers were used to monitor MVPA (≥3.5 METs) during a period of two weeks, and knee radiographs were used to obtain three knee breadth measurements (femoral biepicondylar breadth, mediolateral breadth of femoral condyles, mediolateral breadth of the tibial plateau). The association between MVPA and knee breadth was analyzed using general linear models with adjustments for body mass index, smoking, education years, and accelerometer weartime. Results: Of the sample, 54.8% were women. Most individuals were non-smokers (54.6%) and had 9-12 years of education (69.6%). Mean body mass index was 26.2 (standard deviation 4.3) kg/m2. MVPA was uniformly associated with all three knee breadth measurements among both women and men. For each 60 minutes/day of MVPA, the knee breadth dimensions were 1.8-2.0% (or 1.26-1.42 mm) larger among women (p < 0.001) and 1.4-1.6% (or 1.21-1.28 mm) larger among men (p < 0.001). Conclusions: Higher MVPA is associated with larger tibiofemoral joint size. Our findings indicate that MVPA could potentially increase knee dimensions through similar biomechanical mechanisms it affects diaphyseal morphology, thus offering a potential target in reducing tissue strains and preventing knee problems. Further studies are needed to confirm and investigate the association between articulation area and musculoskeletal health.Peer reviewe

Atomic force microscope adhesion measurements and atomistic molecular dynamics simulations at different humidities

Due to their operation principle atomic force microscopes (AFMs) are sensitive to all factors affecting the detected force between the probe and the sample. Relative humidity is an important and often neglected-both in experiments and simulations-factor in the interaction force between AFM probe and sample in air. This paper describes the humidity control system designed and built for the interferometrically traceable metrology AFM (IT-MAFM) at VTT MIKES. The humidity control is based on circulating the air of the AFM enclosure via dryer and humidifier paths with adjustable flow and mixing ratio of dry and humid air. The design humidity range of the system is 20-60 % rh. Force-distance adhesion studies at humidity levels between 25 % rh and 53 % rh are presented and compared to an atomistic molecular dynamics (MD) simulation. The uncertainty level of the thermal noise method implementation used for force constant calibration of the AFM cantilevers is 10 %, being the dominant component of the interaction force measurement uncertainty. Comparing the simulation and the experiment, the primary uncertainties are related to the nominally 7 nm radius and shape of measurement probe apex, possible wear and contamination, and the atomistic simulation technique details. The interaction forces are of the same order of magnitude in simulation and measurement (5 nN). An elongation of a few nanometres of the water meniscus between probe tip and sample, before its rupture, is seen in simulation upon retraction of the tip in higher humidity. This behaviour is also supported by the presented experimental measurement data but the data is insufficient to conclusively verify the quantitative meniscus elongation.Peer reviewe

A técnica do questionário na pesquisa educacional

O presente trabalho almeja discutir o emprego do questionário enquanto técnica de coleta de dados, recorrentemente empregada nas pesquisas que envolvem o levantamento de uma grande quantidade de dados, como também o seu emprego nas pesquisas de cunho qualitativo. Aqui, decidiu-se pelo recorte espacial de estudo dessa técnica, especificamente, orientado para trabalhos de conclusão de curso de graduandos dos cursos tecnológicos de instituição de ensino superior privada. Este trabalho pretende demonstrar a importância da pesquisa na construção do conhecimento e destacar a urgência de se socializar e divulgar o conhecimento científico entre os discentes de nível superior como forma de conhecer, participar e intervir na realidade. Soma-se a isso, a partir da identificação percebida pelos autores quando da orientação de trabalhos de conclusão de curso, a necessidade de apontar a relevância da escolha adequada da técnica de coleta de dados para o alcance dos resultados esperados. Pretende, ainda, mostrar que o questionário é uma técnica bastante viável e pertinente para ser empregada quando se trata de problemas cujos objetos de pesquisa correspondem a questões de cunho empírico, envolvendo opinião, percepção, posicionamento e preferências dos pesquisados. Neste sentido, busca-se destacar a forma pela qual são construídas as perguntas do questionário, atentando-se para o conteúdo, número e ordem das questões, uma vez que as perguntas são as responsáveis pelo alcance das respostas ao desenvolvimento dos trabalhos. Este estudo fundamenta-se nos autores que tratam da temática, tendo como principais fontes de pesquisa os autores: GIL (1999), RICHARDSON (1999), MARCONE (1999), MALHOTRA (2006), MATALLO (2000), GIL (1996) e RIBEIRO (2008)

Suomen on varauduttava ilmastokriisiin - 6 ohjetta sitkeän ja vähähiilisen yhteiskunnan rakentamiseen

Non peer reviewe