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search for long-lived particles with displaced vertices in multijet events in proton-proton collisions at root s=13 TeV
No full textResults are reported from a search for long-lived particles in proton-proton collisions at root s = 13 TeV delivered by the CERN LHC and collected by the CMS experiment. The data sample, which was recorded during 2015 and 2016, corresponds to an integrated luminosity of 38.5 fb(-1). This search uses benchmark signal models in which long-lived particles are pair-produced and each decays into two or more quarks, leading to a signal with multiple jets and two displaced vertices composed of many tracks. No events with two well-separated high-track-multiplicity vertices are observed. Upper limits are placed on models of R-parity violating supersymmetry in which the long-lived particles are neutralinos or gluinos decaying solely into multijet final states or top squarks decaying solely into dijet final states. For neutralino, gluino, or top squark masses between 800 and 2600 GeV and mean proper decay lengths between 1 and 40 mm, the analysis excludes cross sections above 0.3 fb at 95% confidence level. Gluino and top squark masses are excluded below 2200 and 1400 GeV, respectively, for mean proper decay lengths between 0.6 and 80 mm. A method is provided for extending the results to other models with pair-produced long-lived particles
Automatic intonation classification using temporal patterns in utterance-level pitch contour and perceptually motivated pitch transformation
No full textSecond language learners of British English (BE) are typically trained for four intonation classes: Glide-up, Glide-down, Dive, and Take-off. Automatic four-way intonation classification could be useful to evaluate a learner's pronunciation. However, such automatic classification is challenging without having manually annotated tones, typically considered in intonation analysis and classification tasks. In this, a three-dimensional feature sequence is proposed representing temporal patterns in the utterance-level f0 contour using a perceptually motivated pitch transformation. Hidden Markov model based classification experiments conducted using a training material for teaching BE intonation demonstrate the benefit of the proposed approach over the baseline scheme considered. (C) 2018 Acoustical Society of America
A RISC-V ISA Compatible Processor IP for SoC
No full textThe emergence of System-on-Chip technology has brought in opportunities in the form of reduced cycle time, superior performance and time-to-market considerations. Our work focusses on a new processor for a System on Chip. The system has a 32-bit, 5-stage pipelined processor, memory subsystem with virtual memory support, interrupt controller, memory error control module, and UART. The processor is based on RISC-V ISA. It supports Integer, Multiply, and Atomic instructions. Memory subsystem includes split caches and translation lookaside buffers. Interrupt controller supports four levels of preemptive priority and preemption can be programmed for individual interrupts. Memory error control module provides single error correction and double error detection for main memory. Wishbone B.3 bus standard is adopted as on-chip bus protocol. The design is implemented on Virtex-7 (XC7VX485tffg1761-2) board and achieves a peak clock frequency of 100MHz
Characterizing and Modeling of Mechanical Properties of Epoxy Polymer Composites Reinforced with Bentonite Clay
No full textPolymer nano composites using clay as filler material and epoxy as matrix materials were prepared with different concentrations of clay nano particles (2.5-10 wt%) by shear mixing followed by ultra-sonication process. The mechanical properties such as compressive properties and tensile properties were characterized using ASTM standards. It was found that the addition of clay nano particles improved both compressive strength and tensile strength of pure epoxy significantly. As the clay content increased in epoxy matrix the moduli values found to increase and were further analyzed using micromechanical models. The analytical models discussed correlate well with experimental values. The models discussed include Nicolais - Narkis, Turcsanyi, Piggot Leidner and Nielsen models for the tensile strength values and for tensile modulus the models discussed include Halpin Tsai, Kerner and Sato - Furukawa models. These micromechanics models predict stiffness of nanocomposites with both aligned and randomly oriented fillers. XRD pattern revealed the interaction between clay nanoparticles and epoxy matrix. The thermal decomposition behavior revealed that there is an enhancement of onset of decomposition temperature by 31 degrees C for 10wt% clay filled epoxy than that of pure epoxy for 5% weight loss. (c) 2018 Elsevier Ltd. All rights reserved
Migrating VM workloads to Containers: Issues and Challenges
No full textVirtualization technologies such as KVM and XEN have served the purpose of workload consolidation while providing required isolation. With the advent of Linux Docker platform, micro-service architectures have gained popularity. Adaptation of containers have changed the way, the applications are architected, developed, deployed and managed. Compared to Virtualization, containers provide lightweight alternative to co-host multiple applications on single server at the cost of isolation. This paper highlights the issues and challenges associated with migrating VM based workloads to Container platforms. A systematic analysis, illustrated through a representative application benchmark chosen from a real-life e-commerce private cloud setup is used to present these aspects. Specifically, the application workflow that is currently hosted on VMs is chosen and re-casted on to containers platform and a critical study is conducted based on resource sharing, concurrency, isolation and dependability parameters
Searches for pair production of charginos and top squarks in final states with two oppositely charged leptons in proton-proton collisions at root s=13 TeV
No full textA search for pair production of supersymmetric particles in events with two oppositely charged leptons (electrons or muons) and missing transverse momentum is reported. The data sample corresponds to an integrated luminosity of 35.9 fb(-1) of proton-proton collisions at TeV collected with the CMS detector during the 2016 data taking period at the LHC. No significant deviation is observed from the predicted standard model background. The results are interpreted in terms of several simplified models for chargino and top squark pair production, assuming R-parity conservation and with the neutralino as the lightest supersymmetric particle. When the chargino is assumed to undergo a cascade decay through sleptons, with a slepton mass equal to the average of the chargino and neutralino masses, exclusion limits at 95% confidence level are set on the masses of the chargino and neutralino up to 800 and 320 GeV, respectively. For top squark pair production, the search focuses on models with a small mass difference between the top squark and the lightest neutralino. When the top squark decays into an off-shell top quark and a neutralino, the limits extend up to 420 and 360 GeV for the top squark and neutralino masses, respectively
Evaporation excites temporal sequence of resonant modes in a sessile droplet perturbed at constant frequency - Insights into the universal dynamics of mode transitions
No full textA sessile droplet excited at a constant frequency exhibits a temporal sequence of interface modes when allowed to evaporate. Evaporation tunes the droplet to resonate at different modes in a descending order. The life of each mode spans over a transition stage from the onset of its own resonance to that of the next lower order mode. Mode lifetime during the evaporation period of any droplet has been found to decrease in a power law fashion both theoretically and experimentally when higher driving frequencies are considered. Such dynamics are driven by both evaporation and interface oscillations, the latter being governed by the dispersion relation of one dimensional capillary wave. The natural excitation of sequential mode resonances in the present case is governed by a tuning parameter. Variation of this parameter by evaporation is analogous to external frequency sweep in non evaporating droplets to detect similar mode resonances. The dynamics of transition stage corresponding to each mode is characterized by a second parameter denoted as mode transition parameter. The transition stage (higher to lower order) is initially fast but slows down close to the resonance of lower order mode. Theoretical expressions of mode lifetimes and the tuning parameter have been derived based on reasonably valid assumption of constant static contact angle (a measure of the contact angle of the unperturbed hypothetical droplet shape in an oscillation cycle). An approximate linear relation has been established between detuning (complement of the tuning parameter) and mode transition parameters which governs the dynamics of the transition stage. The experimental data corresponding to the detuning and mode transition parameters show universal merging for all excitation frequencies. The experimental data also follows the proposed theoretical linear trend but deviates towards the later part of the transition stage. Such deviations have been attributed to neglecting higher order terms and possible viscous damping from boundary layer at the substrate. Even then the universality of mode transition across all frequencies is maintained throughout the evaporative lifetime. (C) 2017 Elsevier Ltd. All rights reserved
Soil properties and organic matter quality in relation to climate and vegetation in southern Indian tropical ecosystems
No full textSoil organic matter (SOM) quantity and quality can be directly altered by climate, and SOM has been proposed as both a significant source and sink of carbon dioxide. To understand the factors that influence SOM, the present study focuses on the relationship between precipitation and soil physical and chemical properties along a rainfall-vegetation gradient in a seasonally dry tropical forest in the Western Ghats, southern India. Soil pH decreased with increasing rainfall, but soil organic carbon (SOC) and nitrogen (N) slightly increased. Rainfall had strong positive correlations with standing litter (Pearson's r = 0.85), clay content (r = 0.69) and recalcitrant organic matter (r = 0.73) (all P < 0.05), and chemical properties SOC (r = 0.85), N (r = 0.71), magnesium (r = 0.65), iron (r = 0.64) and zinc (r = 0.75) (all P < 0.05). The heavy fraction, which was bound to mineral particles, comprised more than 60% of the SOM in all sites. The heavy fraction was positively correlated with rainfall and showed a higher proportion in the high rainfall forest soils. Thermal recalcitrant organic matter, such as carbohydrates - and other aliphatic compounds, such as lignin and polyphenols - were also higher in high rainfall forest soils, suggesting a greater effect of SOM turnover. The SOM content and quality were lower in the dry forest soils, which were mainly limited by annual precipitation, but clay content also contributed significantly to SOC storage
Linear Quadratic Regulator-Based Bumpless Transfer in Microgrids
No full textThis paper presents a linear quadratic regulator (LQR)-based bumpless transfer controller for achieving seamless transition between the grid connected and the islanded modes of operation in microgrids. During the grid connected mode, the inverter-based distributed generators (DGs) operate in current controlled mode where they supply a constant active and reactive power. During the islanded mode, the inverters operate in voltage controlled mode. During transition between the two control modes severe transients can occur in the system which affect the voltage and frequency responses. The proposed bumpless compensator reduces the error between the outputs of two controllers at the instant of transition by optimally reducing an error measure based on LQR theory. The efficacy of the proposed controller is tested on a microgrid test system. Several operating scenarios on the microgrid have been tested using the proposed approach. It has been found that the proposed controller is effective in reducing the voltage and the frequency transients during transition
Study of CPO resonances on the intercombination line in Yb-173
No full textWe study coherent population oscillations in an odd isotope of the two-electron atom Yb. The experiments are done using magnetic sublevels of the F-g = 5/2 -> F-e = 3/2 hyperfine transition in Yb-173 of the S-1(0) -> P-3(1) intercombination line. The experiments are done both with and without an applied magnetic field. In the absence of an applied field, the complicated sublevel structure along with the saturated fluorescence effect causes the linewidth to be larger than the 190 kHz natural linewidth of the transition. In the presence of a field (of magnitude 330 mG), a well-defined quantization axis is present which results in the formation of two M-type systems. The total fluorescence is then limited by spin coherence among the ground sublevels. In addition, the pump beam gets detuned from resonance which results in a reduced scattering rate from the P-3(1) state. Both of these effects result in a reduction of the linewidth to a subnatural value of about 100 kHz