5,012 research outputs found

    Hitch your wagon to institutional goals

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    The landscape of accreditation and accountability in higher education is in a period of rapid change, coalescing around issues identified in the 2006 report of the Spellings Commission, “A Test of Leadership: Charting the Future of U.S. Higher Education.” Information literacy librarians need to connect their instructional efforts to the institutional strategies and initiatives that address continuous improvement whatever their source, e.g. accreditation agencies, funding bodies such as state legislatures, institutional participation in the Voluntary System of Accountability (VSA), University & College Accountability Network (U-CAN), or internal initiatives of the institution’s administration. The challenge for instruction librarians is great, requiring delivery and assessment of educational programs while simultaneously facilitating the library administration’s engagement with institutional education initiatives. It is our fundamental belief, however, that the library is poised to be in a position of leadership when it comes to answering these external pressures on higher education for accountability. The Information Literacy QEP at Trinity University illustrates a number of the leadership challenges that instruction librarians must engage and their example is one that will encourage us to continue to grow in the area of assessment of student learning. While all solutions will be local, the lessons learned from the Trinity experience regarding institutional engagement and cultural change can be generalized

    Jointly Optimal Channel Pairing and Power Allocation for Multichannel Multihop Relaying

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    We study the problem of channel pairing and power allocation in a multichannel multihop relay network to enhance the end-to-end data rate. Both amplify-and-forward (AF) and decode-and-forward (DF) relaying strategies are considered. Given fixed power allocation to the channels, we show that channel pairing over multiple hops can be decomposed into independent pairing problems at each relay, and a sorted-SNR channel pairing strategy is sum-rate optimal, where each relay pairs its incoming and outgoing channels by their SNR order. For the joint optimization of channel pairing and power allocation under both total and individual power constraints, we show that the problem can be decoupled into two subproblems solved separately. This separation principle is established by observing the equivalence between sorting SNRs and sorting channel gains in the jointly optimal solution. It significantly reduces the computational complexity in finding the jointly optimal solution. It follows that the channel pairing problem in joint optimization can be again decomposed into independent pairing problems at each relay based on sorted channel gains. The solution for optimizing power allocation for DF relaying is also provided, as well as an asymptotically optimal solution for AF relaying. Numerical results are provided to demonstrate substantial performance gain of the jointly optimal solution over some suboptimal alternatives. It is also observed that more gain is obtained from optimal channel pairing than optimal power allocation through judiciously exploiting the variation among multiple channels. Impact of the variation of channel gain, the number of channels, and the number of hops on the performance gain is also studied through numerical examples.Comment: 15 pages. IEEE Transactions on Signal Processin

    Frustration driven structural distortion in VOMoO4

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    Nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), magnetization measurements and electronic structure calculations in VOMoO4 are presented. It is found that VOMoO4 is a frustrated two-dimensional antiferromagnet on a square lattice with competing exchange interactions along the side J1 and the diagonal J2 of the square. From magnetization measurements J1+J2 is estimated around 155 K, in satisfactory agreement with the values derived from electronic structure calculations. Around 100 K a structural distortion, possibly driven by the frustration, is evidenced. This distortion induces significant modifications in the NMR and EPR spectra which can be accounted for by valence fluctuations. The analysis of the spectra suggests that the size of the domains where the lattice is distorted progressively grows as the temperature approaches the transition to the magnetic ground state at Tc=42 K

    Inviscid Large deviation principle and the 2D Navier Stokes equations with a free boundary condition

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    Using a weak convergence approach, we prove a LPD for the solution of 2D stochastic Navier Stokes equations when the viscosity converges to 0 and the noise intensity is multiplied by the square root of the viscosity. Unlike previous results on LDP for hydrodynamical models, the weak convergence is proven by tightness properties of the distribution of the solution in appropriate functional spaces

    Evidence for an unconventional magnetic instability in the spin-tetrahedra system Cu_2Te_2O_5Br_2

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    Thermodynamic experiments as well as Raman scattering have been used to study the magnetic instabilities in the spin-tetrahedra systems Cu_2Te_2O_5X_2, X=Cl and Br. While the phase transition observed in the Cl system at T_o=18.2 K is consistent with 3D AF ordering, the phase transition at T_o=11.3 K in the Br system has several unusual features. We propose an explanation in terms of weakly coupled tetrahedra with a singlet-triplet gap and low lying singlets.Comment: 4 pages, 4 figure

    Unusual magnetic properties of the low-dimensional quantum magnet Na2V3O7

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    We report the results of low-temperature measurements of the specific heat Cp(T), ac susceptibility chi(T) and 23Na nuclear magnetic resonance NMR of Na2V3O7. At liquid He temperatures Cp(T)/T exhibits broad field-dependent maxima, which shift to higher temperatures upon increasing the applied magnetic field H. Below 1.5 K the ac magnetic susceptibility chi(T) follows a Curie-Weiss law and exhibits a cusp at 0.086 mK which indicates a phase transition at very low temperatures. These results support the previous conjecture that Na2V3O7 is close to a quantum critical point (QCP) at mu_{0}H = 0 T. The entire data set, including results of measurements of the NMR spin-lattice relaxation 1/T1(T), reveals a complex magnetic behavior at low temperatures. We argue that it is due to a distribution of singlet-triplet energy gaps of dimerized V moments. The dimerization process evolves over a rather broad temperature range around and below 100 K. At the lowest temperatures the magnetic properties are dominated by the response of only a minor fraction of the V moments.Comment: 10.5 pages, 15 figures. Submitted to Phys. Rev.

    Test-retest reliability of ski-specific aerobic, sprint, and neuromuscular performance tests in highly trained cross-country skiers.

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    Laboratory tests are commonly performed by cross-country (XC) skiers due to the challenges of obtaining reliable performance indicators on snow. However, only a few studies have reported reliability data for ski-specific test protocols. Therefore, this study examined the test-retest reliability of ski-specific aerobic, sprint, and neuromuscular performance tests. Thirty-nine highly trained XC skiers (26 men and 13 women, age: 22 ± 4 years, V̇O <sub>2max</sub> : 70.1 ± 4.5 and 58.8 ± 4.4 mL·kg <sup>-1</sup> ·min <sup>-1</sup> , respectively) performed two test trials within 6 days of a diagonal V̇O <sub>2max</sub> test, n = 27; skating graded exercise test to assess the second lactate threshold (LT <sub>2</sub> ), n = 27; 24-min double poling time trial (24-min DP, n = 25), double poling sprint test (Sprint <sub>DP1</sub> , n = 27), and 1-min self-paced skating sprint test (Sprint <sub>1-min</sub> , n = 26) using roller skis on a treadmill, and an upper-body strength test (UB-ST, n = 27) to assess peak power (P <sub>peak</sub> ) with light, medium, and heavy loads. For each test, the coefficient of variation (CV), intraclass correlation coefficient (ICC), and minimal detectable change (MDC) were calculated. V̇O <sub>2max</sub> demonstrated good-to-excellent reliability (CV = 1.4%; ICC = 0.99; MDC = 112 mL·min <sup>-1</sup> ), whereas moderate-to-excellent reliability was found for LT <sub>2</sub> (CV = 3.1%; ICC = 0.95). Performance during 24-min DP, Sprint <sub>DP1</sub> , and Sprint <sub>1-min</sub> showed good-to-excellent reliability (CV = 1.0%-2.3%; ICC = 0.96-0.99). Absolute reliability for UB-ST P <sub>peak</sub> was poor (CV = 4.9%-7.8%), while relative reliability was excellent (ICC = 0.93-0.97) across the loads. In highly trained XC skiers, sport-specific aerobic and sprint performance tests demonstrated high test-retest reliability, while neuromuscular performance for the upper body was less reliable. Using the presented protocols, practitioners can assess within- and between-season changes in relevant performance indicators

    A Method Helping to Define Eco-innovative Systems Based on Upgradability

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    AbstractEnvironmental issues due to emerging markets and rapid development of consumer goods’ consumption require a new model to design more sustainable products. While traditional eco-design methods (LCA, Check-lists, Guidelines, DfX tools…) are generally restricted to a local optimization of the product or to macro-rules for defining an environmental strategy, this article presents an eco-innovative method based on product upgradability which is the integration of functional enrichments on the product. Indeed, the integration of upgrades offers new opportunities for facilitating the dissemination of the remanufacturing approach, the dissemination of Product-Service Systems, or for increasing the lifetime of product.This article presents an eco-innovative method based on upgradability consisting in: exploring the potential upgrades of modules - PMoL (SADT activity A4), the potential value network structures for upgradability - VaNS (A3) and the potential serviceable upgrades including eco-learning strategies - SMoL (A5). This method combines then the results PMoL, VaNS and SMoL to form promising Upgradable Modules Scenarios – UpMoS (A6), which are completed by the specification of an associated value network (A7) and the consolidation of eco-usage services and services offers (A8). The final result obtained, Upgradable systems concepts– UpSys are then assessed thanks to a multicriteria approach (A9) considering environmental, economic and user's and stakeholder's attractiveness criteria.To summarize, this method is structured in two rounds. The first round (A3, A4, A5) aims to explore widely the possibilities offered by the upgradability avoiding the complexity of an approach dealing with several parameters simultaneously. The purpose of the second round (A6, A7, A8, A9) is to specify and assess Upgradable systems encompassing the overall results of the exploration. Before performing this work, relevant information needs to be collected for the project (market information, customer segments, technologies, stakeholders, environmental impacts of the current product, etc.) and acceptability domains of upgradable systems have to be analyzed (A1, A2).This paper presents therefore this eco-innovative approach based on five founding principles and answering to the requirements identified in the literature for a good and effective eco-design method

    Physiological requirements in triathlon

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    This article aims to present the current knowledge on physiological requirements in Olympic distance and Ironman triathlon. Showing the data available from a “traditional point of view” (aerobic power, anaerobic threshold, heart rate, running economy) and from a “contemporary” point of view (V̇ O2 kinetics), it emphasises where we are currently and the areas that remain unknown

    Rate of Convergence of Space Time Approximations for stochastic evolution equations

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    Stochastic evolution equations in Banach spaces with unbounded nonlinear drift and diffusion operators driven by a finite dimensional Brownian motion are considered. Under some regularity condition assumed for the solution, the rate of convergence of various numerical approximations are estimated under strong monotonicity and Lipschitz conditions. The abstract setting involves general consistency conditions and is then applied to a class of quasilinear stochastic PDEs of parabolic type.Comment: 33 page
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