5,948 research outputs found

    More bits - more bucks? Measuring the impact of broadband internet on firm performance

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    The paper provides empirical evidence for the causal impact of broadband Internet on the economic performance of German firms. Performance is measured in terms of labour productivity and realised process and product innovations. The analysis refers to the early phase of DSL expansion in Germany from 2001 to 2003, when roughly 60 percent of the German firms already used broadband Internet. Identification relies on instrumental variable estimation taking advantage of information on the availability of DSL broadband at the postal code level. The results show that broadband Internet has no impact on firms' labour productivity whereas it exhibits a positive and significant impact on their innovation activity. --labour productivity,innovation,broadband Internet

    Self-healing polymers

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    A three dimensional structure fabricated from a self-healing polymeric material, comprising poly(ester amides) obtained from ethylene glycol, azelaic acid and 1,1-aminoundecanoic acid, wherein polymeric material has a melt index above 2.5 g/10 min. as determined by ASTM D1238 at 190.degree. C. and 2.16kg, impact resistance and ductility sufficient to resist cracking and brittle fracture upon impact by a 9 mm bullet fired at a temperature of about 29.degree. C. at subsonic speed in a range from about 800 feet/sec to about 1000 feet/sec. It has been determined that the important factors necessary for self-healing behavior of polymers include sufficient impact strength, control of the degree of crystallinity, low melting point and the ability to instantly melt at impacted area

    Intermediate input markets, ICT and innovation in Germany: a firm level analysis

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    This paper studies the impact of the adoption of ICT on the economic performance at the firm level, considering explicitly the interaction of adopting firms within the intermediate input market in Germany. The paper identifies and quantifies the importance of adoption externalities and knowledge spillovers inherent in the introduction of ICT. The results show that the adoption of ICT at the firm level is positively affected by the use of ICT downstream and upstream (i.e. by a firm’s clients and suppliers). Moreover, the use of ICT upstream(i.e. by a firm’s suppliers) negatively affects the extend of IT outsourcing at the firm level, suggesting a substitution effect between inputs provided by suppliers with an intense use of ICT and a firm’s demand for external IT services. The paper also finds that the use of ICT within the intermediate input markets positively affects the efficiency of internal processes by increasing the cost reductions generated by the introduction of process innovations

    Endogenous firm heterogeneity, ICT and R&D incentives

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    Firm heterogeneity explains the productivity driven selection mechanism that determines aggregate productivity growth within industries. This paper empirically demonstrates that ICT has a robust impact on firm heterogeneity only when ICT is used intensively and jointly with specific ICT applications. ICT induced heterogeneity is shown to have a positive impact on the decision to invest in R&D personnel

    An Investigation of the Intrinsic and Extrinsic Influences on the Aggressive Behavior of Crayfish

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    Several influences have been identified as important in determining aggressive (i.e. agonistic) hierarchy formation in crayfish, however the relative significance of these factors has yet to be determined. This study compares several aggressive influences, including previous winning or losing experiences, prior shelter possession, starvation, olfaction obstruction, and control treatments to determine which of these factors affect aggressive interactions to the greatest extent. The analysis will reveal which of these effects is strongest when directly confronted against one another. Each crayfish received one of the above treatments and then interacts with another size-matched crayfish that received a different treatment. All trials were recorded and then analyzed using a blind analysis scheme. Trials of each experimental treatment versus a size-matched naive crayfish have been completed to date, and the cross-comparison trials are currently in progress

    More bits more bucks? : Measuring the impact of broadband internet on firm performance

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    The paper provides empirical evidence for the causal impact of broadband Internet on the economic performance of German firms. Performance is measured in terms of labour productivity and realised process and product innovations. The analysis refers to the early phase of DSL expansion in Germany from 2001 to 2003, when roughly 60 percent of the German firms already used broadband Internet. Identification relies on instrumental variable estimation taking advantage of information on the availability of DSL broadband at the postal code level. The results show that broadband Internet has no impact on firms' labour productivity whereas it exhibits a positive and significant impact on their innovation activity

    The Separatrix Algorithm for Synthesis and Analysis of Stochastic Simulations with Applications in Disease Modeling

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    Decision makers in epidemiology and other disciplines are faced with the daunting challenge of designing interventions that will be successful with high probability and robust against a multitude of uncertainties. To facilitate the decision making process in the context of a goal-oriented objective (e.g., eradicate polio by ), stochastic models can be used to map the probability of achieving the goal as a function of parameters. Each run of a stochastic model can be viewed as a Bernoulli trial in which “success” is returned if and only if the goal is achieved in simulation. However, each run can take a significant amount of time to complete, and many replicates are required to characterize each point in parameter space, so specialized algorithms are required to locate desirable interventions. To address this need, we present the Separatrix Algorithm, which strategically locates parameter combinations that are expected to achieve the goal with a user-specified probability of success (e.g. 95%). Technically, the algorithm iteratively combines density-corrected binary kernel regression with a novel information-gathering experiment design to produce results that are asymptotically correct and work well in practice. The Separatrix Algorithm is demonstrated on several test problems, and on a detailed individual-based simulation of malaria

    MARDELS: A full-sky X-ray selected galaxy cluster catalog

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    We present the MARDELS catalog of 8,471 X-ray selected galaxy clusters over 25,000 deg^2 of extragalactic sky. The accumulation of deep, multiband optical imaging data, the development of the optical counterpart classification algorithm MCMF, and the release of the DESI Legacy Survey DR10 catalog covering the extragalactic sky makes it possible -- for the first time, more than 30 years after the launch of the ROSAT X-ray satellite -- to identify the majority of the galaxy clusters detected in the ROSAT All-Sky-Survey source catalog (2RXS). The resulting 90% pure MARDELS catalog is the largest ICM-selected cluster sample to date. MARDELS probes a large dynamic range in cluster mass spanning from galaxy groups to the most massive clusters in the Universe. The cluster redshift distribution peaks at z~0.1 and extends to redshifts z~1. Out to z~0.4, the MARDELS sample contains more clusters per redshift interval (dN/dz) than any other ICM-selected sample. In addition to the main sample, we present two subsamples with 6,930 and 5,522 clusters, exhibiting 95% and 99% purity, respectively. We forecast the utility of the sample for a cluster cosmological study, using realistic mock catalogs that incorporate most observational effects, including the X-ray exposure time and background variations, the existence likelihood selection adopted in 2RXS and the impact of the optical cleaning with MCMF. Using realistic priors on the observable--mass relation parameters from a DES-based weak lensing analysis, we estimate the constraining power of the MARDELSxDES sample to be of 0.026, 0.033 and 0.15 (1σ1\sigma) on the parameters Ωm\Omega_\mathrm{m}, σ8\sigma_8 and ww, respectively.Comment: 20 pages, 11 figures, submitted to MNRA

    Assessment of Sport Nutrition Knowledge, Dietary Practices, and Sources of Nutrition Information in NCAA Division III Collegiate Athletes.

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    Nutrition knowledge is a critical component of meeting sport nutrition guidelines. The present study aimed to evaluate the sport nutrition knowledge of National Collegiate Athletic Association (NCAA) Division III (DIII) athletes using a validated questionnaire, and to assess the dietary practices and sources of nutrition information in this population. A total of 331 student-athletes
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