286 research outputs found

    Environmental impact assessment of online advertising

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    There are no commonly agreed ways to assess the total energy consumption of the Internet. Estimating the Internet's energy footprint is challenging because of the interconnectedness associated with even seemingly simple aspects of energy consumption. The first contribution of this paper is a common modular and layered framework, which allows researchers to assess both energy consumption and CO2e emissions of any Internet service. The framework allows assessing the energy consumption depending on the research scope and specific system boundaries. Further, the proposed framework allows researchers without domain expertise to make such an assessment by using intermediate results as data sources, while analyzing the related uncertainties. The second contribution is an estimate of the energy consumption and CO2e emissions of online advertising by utilizing our proposed framework. The third contribution is an assessment of the energy consumption of invalid traffic associated with online advertising. The second and third contributions are used to validate the first. The online advertising ecosystem resides in the core of the Internet, and it is the sole source of funding for many online services. Therefore, it is an essential factor in the analysis of the Internet's energy footprint. As a result, in 2016, online advertising consumed 20–282 TWh of energy. In the same year, the total infrastructure consumption ranged from 791 to 1334 TWh. With extrapolated 2016 input factor values without uncertainties, online advertising consumed 106 TWh of energy and the infrastructure 1059 TWh. With the emission factor of 0.5656 kg CO2e/kWh, we calculated the carbon emissions of online advertising, and found it produces 60 Mt CO2e (between 12 and 159 Mt of CO2e when considering uncertainty). The share of fraudulent online advertising traffic was 13.87 Mt of CO2e emissions (between 2.65 and 36.78 Mt of CO2e when considering uncertainty). The global impact of online advertising is multidimensional. Online advertising affects the environment by consuming significant amounts of energy, leading to the production CO2e emissions. Hundreds of billions of ad dollars are exchanged yearly, placing online advertising in a significant role economically. It has become an important and acknowledged component of the online-bound society, largely due to its integration with the Internet and the amount of revenue generated through it

    Is blockchain ready to revolutionize online advertising?

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    The 200-billion-dollar per annum online advertising ecosystem has become infested with thousands of intermediaries exploiting user data and advertising budgets. All key stakeholders in the value-chain are infected: advertisers with fraud, publishers with their diminishing share of advertising budgets, and users with their right to privacy. Blockchain presents a possible solution to addressing the critical issues in the online advertising supply chain. The question remains whether blockchain scalability, energy-efficiency, and token volatility issues can be solved in the coming years to the extent that online advertising could widely leverage trustlessness and the benefits gained from blockchain technology. This paper aims to review the current progress and to open a discussion to address the issues. We present new requirements for blockchain-based online advertising solutions. We have also analyzed the available solutions against the requirements and recommend directions for future research and solution development. Evidence from our research points out that blockchain is not yet ready to be widely implemented in online advertising. More research is needed, and new proof-of-concepts need to be developed before blockchain technology can be considered a trusted alternative for the current online advertising marketplace based on open real-time bidding

    Heredity of interocular similarities in components of refraction : a population-based twin study among 66-to 79-year-old female twins

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    Purpose To examine genetic influences on interocular similarities in ocular refraction and components of refraction among elderly female twins. Methods Refraction was assessed in 94 monozygotic (MZ) and 74 dizygotic (DZ) female twins aged 66-78 years. Absolute values of interocular differences (Aniso variables) in spherical refraction (SR), refractive astigmatism (AST), spherical equivalent (SE), corneal refractive power (CR), corneal astigmatism (CAST), anterior chamber depth (ACD) and axial length (AL) were calculated. The differences between sisters in each of the Aniso variables were calculated and graded into two categories, best differentiating the groups, here isometropic and anisometropic values. The cut-offs for grading as isometropic were AnisoSR <0.75 D, AnisoAST <0.5 D, AnisoSE <1.0 D, AnisoCR <0.5 D, AnisoCAST <0.50 D, AnisoACD AL MZ and DZ pairs in the Aniso variables and the interrelationships between the Aniso variables. Results When the Aniso variables were treated as continuous, no significant differences were found between the MZ and DZ subjects. When the proportions of isometropic intratwinpair interocular differences in the Aniso variables in the MZ and DZ cotwins were compared, the prevalences (MZ/DZ) were AnisoSR: 68%/60%; AnisoAST: 66%/57%; AnisoSE: 87%/68%; AnisoCR: 83%/78%; AnisoCAST: 69%/35%; AnisoACD: 77%/63%; and AnisoAL: 76%/60%. The differences were statistically significant for Aniso SE (p = 0.035, Fisher's exact test) and CAST (p = 0.007). The greater homogeneity in the interocular differences between the MZ sisters supports the assumption that isometropia of different elements of refraction is genetically influenced and tending to continue up to older ages. In cases where AnisoSE was = 1 D, no similar influence on emmetropization was observed. The difference between sisters in AnisoSE was associated with the intratwinpair difference in Aniso AL, but not with the intratwinpair differences in AnisoCR, irrespective of zygosity. Conclusion The higher prevalence of similarities in isometropia of the spherical equivalent and corneal astigmatism between the MZ pairs compared to DZ pairs is consistent with the view that genetic influences on the refractive elements of the eye, tending to isometropia, continue into older age. The interrelation between CR and AL tends to maintain isometropia of SE irrespective of zygosity.Peer reviewe

    Analysis and optimization of packaged inductively degenerated common-source low-noise amplifiers with ESD protection

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    A Gain Stabilization Technique for Tuned RF Low-Noise Amplifiers

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    Calibration techniques of active BiCMOS mixers

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    Enhancement of adhesion and promotion of osteogenic differentiation of human adipose stem cells by poled electroactive poly(vinylidene fluoride)

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    Poly(vinylidene fluoride) (PVDF) is a biocompatible material with excellent electroactive properties. Non-electroactive α-PVDF and electroactive β-PVDF were used to investigate the substrate polarization and polarity influence on the focal adhesion size and number as well as on human adipose stem cells (hASCs) differentiation. hASCs were cultured on different PVDF surfaces adsorbed with fibronectin and focal adhesion size and number, total adhesion area, cell size, cell aspect ratio and focal adhesion density were estimated using cells expressing EGFP-vinculin. Osteogenic differentiation was also determined using a quantitative alkaline phosphatase assay. The surface charge of the poled PVDF films (positive or negative) influenced the hydrophobicity of the samples, leading to variations in the conformation of adsorbed extracellular matrix (ECM) proteins, which ultimately modulated the stem cell adhesion on the films and induced their osteogenic differentiation.The study was supported financially by the Academy of Finland (136288, 140978 and 256931), the Sigrid Jusélius Foundation, the Pirkanmaa Hospital District and the Finnish Funding Agency for Technology and Innovation (TEKES). This study was also supported by FEDER through the COMPETE Program, by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST- C/FIS/UI607/2011 and by projects NANO/NMed-SD/0156/2007 and PTDC/CTM NAN/112574/2009. The autors also thank the project Matepro – Optimizing Materials and Processes”, ref. NORTE-07-0124-FEDER-000037”, co-funded by the “Programa Operacional Regional do Norte” (ON.2 – O Novo Norte), under the “Quadro de Referência Estratégico Nacional” (QREN), through the “Fundo Europeu de Desenvolvimento Regional” (FEDER). V.S. and C.R. thank the FCT for the SFRH/BPD/63148/2009 and SFRH/BPD/90870/2012 grants, respectively
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