Towards virtual machine energy-aware cost prediction in clouds

Pricing mechanisms employed by different service providers significantly influence the role of cloud computing within the IT industry. With the increasing cost of electricity, Cloud providers consider power consumption as one of the major cost factors to be maintained within their infrastructures. Consequently, modelling a new pricing mechanism that allow Cloud providers to determine the potential cost of resource usage and power consumption has attracted the attention of many researchers. Furthermore, predicting the future cost of Cloud services can help the service providers to offer the suitable services to the customers that meet their requirements. This paper introduces an Energy-Aware Cost Prediction Framework to estimate the total cost of Virtual Machines (VMs) by considering the resource usage and power consumption. The VMs’ workload is firstly predicted based on an Autoregressive Integrated Moving Average (ARIMA) model. The power consumption is then predicted using regression models. The comparison between the predicted and actual results obtained in a real Cloud testbed shows that this framework is capable of predicting the workload, power consumption and total cost for different VMs with good prediction accuracy, e.g. with 0.06 absolute percentage error for the predicted total cost of the VM

Languages cool as they expand: Allometric scaling and the decreasing need for new words

We analyze the occurrence frequencies of over 15 million words recorded in millions of books published during the past two centuries in seven different languages. For all languages and chronological subsets of the data we confirm that two scaling regimes characterize the word frequency distributions, with only the more common words obeying the classic Zipf law. Using corpora of unprecedented size, we test the allometric scaling relation between the corpus size and the vocabulary size of growing languages to demonstrate a decreasing marginal need for new words, a feature that is likely related to the underlying correlations between words. We calculate the annual growth fluctuations of word use which has a decreasing trend as the corpus size increases, indicating a slowdown in linguistic evolution following language expansion. This ‘‘cooling pattern’’ forms the basis of a third statistical regularity, which unlike the Zipf and the Heaps law, is dynamical in nature

Constraining New Physics with a Positive or Negative Signal of Neutrino-less Double Beta Decay

We investigate numerically how accurately one could constrain the strengths of different short-range contributions to neutrino-less double beta decay in effective field theory. Depending on the outcome of near-future experiments yielding information on the neutrino masses, the corresponding bounds or estimates can be stronger or weaker. A particularly interesting case, resulting in strong bounds, would be a positive signal of neutrino-less double beta decay that is consistent with complementary information from neutrino oscillation experiments, kinematical determinations of the neutrino mass, and measurements of the sum of light neutrino masses from cosmological observations. The keys to more robust bounds are improvements of the knowledge of the nuclear physics involved and a better experimental accuracy.Comment: 23 pages, 3 figures. Minor changes. Matches version published in JHE

Repetition Enhancement for Frequency-Modulated but Not Unmodulated Sounds: A Human MEG Study

BACKGROUND: Decoding of frequency-modulated (FM) sounds is essential for phoneme identification. This study investigates selectivity to FM direction in the human auditory system. METHODOLOGY/PRINCIPAL FINDINGS: Magnetoencephalography was recorded in 10 adults during a two-tone adaptation paradigm with a 200-ms interstimulus-interval. Stimuli were pairs of either same or different frequency modulation direction. To control that FM repetition effects cannot be accounted for by their on- and offset properties, we additionally assessed responses to pairs of unmodulated tones with either same or different frequency composition. For the FM sweeps, N1m event-related magnetic field components were found at 103 and 130 ms after onset of the first (S1) and second stimulus (S2), respectively. This was followed by a sustained component starting at about 200 ms after S2. The sustained response was significantly stronger for stimulation with the same compared to different FM direction. This effect was not observed for the non-modulated control stimuli. CONCLUSIONS/SIGNIFICANCE: Low-level processing of FM sounds was characterized by repetition enhancement to stimulus pairs with same versus different FM directions. This effect was FM-specific; it did not occur for unmodulated tones. The present findings may reflect specific interactions between frequency separation and temporal distance in the processing of consecutive FM sweeps

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

First United Kingdom Heart and Renal Protection (UK-HARP-I) study: biochemical efficacy and safety of simvastatin and safety of low-dose aspirin in chronic kidney disease.

BACKGROUND: Patients with chronic kidney disease are at increased risk for cardiovascular disease, but the efficacy and safety of simvastatin and aspirin are unknown in this patient group. METHODS: Patients were randomly assigned in a 2 x 2 factorial design to the administration of: (1) 20 mg of simvastatin daily versus matching placebo, and (2) 100 mg of modified-release aspirin daily versus matching placebo. RESULTS: Overall, 448 patients with chronic kidney disease were randomly assigned (242 predialysis patients with a creatinine level > or = 1.7 mg/dL [> or =150 micromol/L], 73 patients on dialysis therapy, and 133 patients with a functioning transplant). Compliance with study treatments was 80% at 12 months. Allocation to treatment with 100 mg of aspirin daily was not associated with an excess of major bleeds (aspirin, 4 of 225 patients [2%] versus placebo, 6 of 223 patients [3%]; P = not significant [NS]), although there was a 3-fold excess of minor bleeds (34 of 225 [15%] versus 12 of 223 patients [5%]; P = 0.001). Among those with predialysis renal failure or a functioning transplant at baseline, aspirin did not increase the number of patients who progressed to dialysis therapy (7 of 187 [4%] versus 6 of 188 patients [3%]; P = NS) or experienced a greater than 20% increase in creatinine level (63 of 187 patients [34%] versus 56 of 188 patients [30%]; P = NS). After 12 months of follow-up, allocation to 20 mg of simvastatin daily reduced nonfasting total cholesterol levels by 18% (simvastatin, 163 mg/dL [4.22 mmol/L] versus placebo, 196 mg/dL [5.08 mmol/L]; P < 0.0001), directly measured low-density lipoprotein cholesterol levels by 24% (89 mg/dL [2.31 mmol/L] versus 114 mg/dL [2.96 mmol/L]; P < 0.0001), and triglyceride levels by 13% (166 mg/dL [1.87 mmol/L] versus 186 mg/dL [2.10 mmol/L]; P < 0.01), but there was no significant effect on high-density lipoprotein cholesterol levels (2% increase; P = NS). Allocation to simvastatin therapy was not associated with excess risk for abnormal liver function test results or elevated creatine kinase levels. CONCLUSION: During a 1-year treatment period, simvastatin, 20 mg/d, produced a sustained reduction of approximately one quarter in low-density lipoprotein cholesterol levels, with no evidence of toxicity, and aspirin, 100 mg/d, did not substantially increase the risk for a major bleeding episode. Much larger trials are now needed to assess whether these treatments can prevent vascular events