On-Disk Data Processing: Issues and Future Directions

In this paper, we present a survey of "on-disk" data processing (ODDP). ODDP, which is a form of near-data processing, refers to the computing arrangement where the secondary storage drives have the data processing capability. Proposed ODDP schemes vary widely in terms of the data processing capability, target applications, architecture and the kind of storage drive employed. Some ODDP schemes provide only a specific but heavily used operation like sort whereas some provide a full range of operations. Recently, with the advent of Solid State Drives, powerful and extensive ODDP solutions have been proposed. In this paper, we present a thorough review of architectures developed for different on-disk processing approaches along with current and future challenges and also identify the future directions which ODDP can take.Comment: 24 pages, 17 Figures, 3 Table

Phases and phase transitions of frustrated hard-core bosons on a triangular ladder

We study hardcore bosons on a triangular ladder at half filling in the presence of a frustrating hopping term and a competing nearest neighbor repulsion $V$ which promotes crystallization. Using the finite-size density-matrix renormalization group method, we obtain the phase diagram which contains three phases: a uniform superfluid (SF), an insulating charge density wave (CDW) crystal and a bond ordered insulator (BO). We find that the transitions from SF to CDW and SF to BO are continuous in nature, with critical exponents varying continously along the phase boundaries, while the transition from CDW to BO is found to be first order. The phase diagram is also shown to contain an exactly solvable Majumdar Ghosh point, and re-entrant SF to CDW phase transitions.Comment: 10 pages, 16 figure

Factors Affecting the Adoption of Genetically Modified Crops by Young and Beginning U.S. Farmers and Ranchers

The comprehensive set of programs in the 2008 Farm Bill designed to support Young and Beginning Farmers and Ranchers (YBFR), combined with a substantial amount of resources allocated to each of these programs, can be viewed as an investment in ensuring the future sustainability of the U.S. agriculture system. Understanding the factors that influence YBFR to adopt technology will become increasingly important if YBFR are to succeed. Of particular interest is why YBFR adopt Bt corn, Bt cotton, and HT soybeans. Results conform to a majority of our a priori expectations; YBFRs are more likely to adopt GM crops if they are not a full owner of the farm operation, as sales of the farm operation grow, if the crop is important to their region, and as they become more risk averse.Agricultural and Food Policy,

Ready-to-use post-Newtonian gravitational waveforms for binary black holes with non-precessing spins: An update

For black-hole binaries whose spins are (anti-) aligned with respect to the orbital angular momentum of the binary, we compute the frequency domain phasing coefficients including the quadratic-in-spin terms up to the third post-Newtonian (3PN) order, the cubic-in-spin terms at the leading order, 3.5PN, and the spin-orbit effects up to the 4PN order. In addition, we obtain the 2PN spin contributions to the amplitude of the frequency-domain gravitational waveforms for non-precessing binaries, using recently derived expressions for the time-domain polarization amplitudes of binaries with generic spins, complete at that accuracy level. These two results are updates to Arun et al. (2009) [1] for amplitude and Wade et al. (2013) [2] for phasing. They should be useful to construct banks of templates that model accurately non-precessing inspiraling binaries, for parameter estimation studies, and or constructing analytical template families that accounts for the inspiral-merger-ringdown phases of the binary.Comment: 8 pages, an additional file (readable in MATHEMATICA) containing all the key results included in the sourc

Gravitational-wave phasing for low-eccentricity inspiralling compact binaries to 3PN order

[abridged] Although gravitational radiation causes inspiralling compact binaries to circularize, a variety of astrophysical scenarios suggest that binaries might have small but nonnegligible orbital eccentricities when they enter the low-frequency bands of ground and space-based gravitational-wave detectors. If not accounted for, even a small orbital eccentricity can cause a potentially significant systematic error in the mass parameters of an inspiralling binary. Gravitational-wave search templates typically rely on the quasi-circular approximation, which provides relatively simple expressions for the gravitational-wave phase to 3.5 post-Newtonian (PN) order. The quasi-Keplerian formalism provides an elegant but complex description of the post-Newtonian corrections to the orbits and waveforms of inspiralling binaries with any eccentricity. Here we specialize the quasi-Keplerian formalism to binaries with low eccentricity. In this limit the non-periodic contribution to the gravitational-wave phasing can be expressed explicitly as simple functions of frequency or time, with little additional complexity beyond the well-known formulas for circular binaries. These eccentric phase corrections are computed to 3PN order and to leading order in the eccentricity for the standard PN approximants. For a variety of systems these eccentricity corrections cause significant corrections to the number of gravitational wave cycles that sweep through a detector's frequency band. This is evaluated using several measures, including a modification of the useful cycles. We also evaluate the role of periodic terms that enter the phasing and discuss how they can be incorporated into some of the PN approximants. While the eccentric extension of the PN approximants is our main objective, this work collects a variety of results that may be of interest to others modeling eccentric relativistic binaries.Comment: 49 pages, 4 figures. Submitted to Phys. Rev. D. Supplementary materials available at http://link.aps.org/supplemental/10.1103/PhysRevD.93.124061. V2: minor updates to match published versio

Relating Maxwell's Demon and Quantitative Analysis of Information Leakage for Practical Imperative Programs

International audienceShannon observed the relation between information entropy and Maxwell demon experiment to come up with information entropy formula. After that, Shannon's entropy formula is widely used to measure information leakage in imperative programs. But in the present work, our aim is to go in a reverse direction and try to find possible Maxwell's demon experimental setup for contemporary practical imperative programs in which variations of Shannon's entropy formula has been applied to measure the information leakage. To establish the relation between the second principle of thermodynamics and quantitative analysis of information leakage, present work models contemporary variations of imperative programs in terms of Maxwell's demon experimental setup. In the present work five contemporary variations of imperative program related to information quantification are identified. They are: (1) information leakage in imperative program (2) imperative multithreaded program (3) point to point leakage in the imperative program (4) imperative program with infinite observation and (5) imperative program in the SOA-based environment. For these variations, minimal work required by an attacker to gain the secret is also calculated using historical Maxwell's demon experiment. To model the experimental setup of Maxwell's demon, non-interference security policy is used. In the present work, imperative programs with one-bit secret information have been considered to avoid the complexity. The findings of the present work from the history of physics can be utilized in many areas related to information flow of physical computing, nano-computing, quantum computing, biological computing, energy dissipation in computing and computing power analysis