Cloud computing: survey on energy efficiency

International audienceCloud computing is today’s most emphasized Information and Communications Technology (ICT) paradigm that is directly or indirectly used by almost every online user. However, such great significance comes with the support of a great infrastructure that includes large data centers comprising thousands of server units and other supporting equipment. Their share in power consumption generates between 1.1% and 1.5% of the total electricity use worldwide and is projected to rise even more. Such alarming numbers demand rethinking the energy efficiency of such infrastructures. However, before making any changes to infrastructure, an analysis of the current status is required. In this article, we perform a comprehensive analysis of an infrastructure supporting the cloud computing paradigm with regards to energy efficiency. First, we define a systematic approach for analyzing the energy efficiency of most important data center domains, including server and network equipment, as well as cloud management systems and appliances consisting of a software utilized by end users. Second, we utilize this approach for analyzing available scientific and industrial literature on state-of-the-art practices in data centers and their equipment. Finally, we extract existing challenges and highlight future research directions

Measurement of atmospheric neutrino oscillations with IceCube

We present the first statistically significant detection of neutrino oscillations in the high-energy regime (>20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (~20 GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20-100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5σ significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters |Δm(32)(2)|=(2.3(-0.5)(+0.6))×10(-3) eV(2) and sin(2)(2θ(23))>0.93, and maximum mixing is favored.M. G. Aartsen ... G. C. Hill ... et al. (IceCube Collaboration

A multi technical study of silver denars from medieval Poland for improved understanding of their archaeological context and provenance

This paper discusses a methodology that involves the use of x amp; 8208;ray fluorescence XRF , high energy particle induced x amp; 8208;ray emission HE amp; 8208;PIXE and particle induced amp; 947; amp; 8208;ray emission HE amp; 8208;PIGE spectroscopies for the study of historic denars with the aim of describing the advantages and limitations of each technique as well as arriving at an archaeometric interpretation of the compositions. Thirty nine medieval Polish denars minted by Kings Boles amp; 322;aw the Brave and Mieszko II Lambert were analysed for their elemental composition. While XRF is limited to the analysis of the material close to the object s surface, high energy ion beam analysis was used to obtain information from Cu at a relatively larger depth. The major elements detected were Ag and Cu, while the minor elements were Pb, Au, Bi, and Zn. An evaluation of the results obtained with the different techniques shows that the content of Cu near the surface is different from the bulk composition of the coins. The obtained elemental composition was used to proliferate the understanding of chronological changes in the production of early medieval Polish denar

Reinigung eiweiss- und fetthaltiger Abwaesser am Beispiel der Gelatineindustrie Abschlussbericht

With 6 tabs., 23 figs.SIGLETIB: FR 3449 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

The within-distribution business cycle dynamics of German firms

In this article, we analyse stylized facts for Germany's business cycle at the firm level. Based on longitudinal firm-level data from the Bundesbank's balance sheet statistics covering, on average, 55 000 firms per year from 1971 to 1998, we estimate transition probabilities of a firm in a certain real sales growth regime switching to another regime in the next period, e.g. whether a firm that has witnessed a high growth rate is likely to stay in a regime of high growth or is bound to switch to a regime of low growth in the subsequent period. We find that these probabilities depend on the business cycle position.

Improvements and Future Challenges for the Research Infrastructure in Public Finance

The paper briefly surveys available data sources and discusses future developments relevant for empirical public finance in Germany. It starts from the notion that public finance deals with decisions of various agents, not only governments, but also private households and firms. Therefore, empirical research needs different types of data. Government decisions are to some extent captured in terms of the budgetary statistics, even though these statistics have shortcomings with regard to the quality of public service provisions and the revenue instruments. To study the decisions of the other agents individual level data is required. While some progress has been made, recently, the combination of various datasets at the individual level is a key priority

Supplementary Material for: Liver fibrosis is associated with poorer overall survival and higher recurrence rate in patients with cholangiocarcinoma

Introduction Cholangiocarcinoma is the second most common primary liver tumour worldwide with an increasing incidence in recent decades. While the effects of fibrosis on hepatocellular carcinoma have been widely demonstrated, the impact on cholangiocarcinoma remains unclear. The aim of this study is to evaluate the impact of liver fibrosis on overall survival (OS) and disease-free survival (DFS) in patients who have undergone liver resection for cholangiocarcinoma. Method 80 patients with cholangiocarcinoma who underwent curatively intended liver surgery between January 2007 and December 2020 were included in this retrospective single-center study. Clinical and histopathological features were analyzed. The primary endpoint was cause-specific survival. Secondary endpoints were DFS and identification of prognostic factors. Results The present study shows that the median OS is significantly reduced in patients with fibrosis (p<0.001). The median OS in patients with fibrosis was three times shorter than in the group without fibrosis. In addition, a significantly shorter DFS was observed in patients with fibrosis (p<0.002). Multivariate analysis showed that fibrosis is the strongest independent factor with a negative impact on OS and DFS. Conclusion Liver fibrosis has a significant impact on OS and DFS in patients with cholangiocarcinoma. Patients with known liver fibrosis require thorough perioperative care and postoperative follow-up