bluuebunny/crossref_metadata_2025_split huggingface dataset:
(GeTe)x–(Sb2Te3)1–x phase‐change thin films as potential thermoelectric materials
Authors: Sittner Ernst‐Roland , Siegert Karl Simon , Jost Peter , Schlockermann Carl , Lange Felix Rolf Lutz , Wuttig Matthias 
Published: September 2012

AbstractPhase‐change materials form a unique material class, characterized by a rather unusual combination of physical properties. Exhibiting fast crystallization and a large contrast in optical reflectivity and electrical conductivity between the amorphous and the crystalline state, they are ideally suited for non‐volatile data storage. Here, we present the thermoelectric properties of Ge3Sb2Te6 and Ge8Sb2Te11 phase‐change alloys measured between room temperature and 120 °C. Both systems display intrinsically high Seebeck coefficients and low thermal conductivities. While low electrical conductivities preclude the employment of Ge3Sb2Te6 in thermoelectric applications, the GeTe rich Ge8Sb2Te11 exhibits high ZTs of up to 0.7 in the temperature range investigated, which renders this alloy a potential p‐type thermoelectric material.
Maximum edge‐cuts in cubic graphs with large girth and in random cubic graphs
Authors: Kardoš František , Král′ Daniel , Volec Jan 
Published: September 2012

AbstractWe show that for every cubic graph Gwith sufficiently large girth there exists a probability distribution on edge‐cuts in Gsuch that each edge is in a randomly chosen cut with probability at least 0.88672. This implies that Gcontains an edge‐cut of size at least 1.33008n, where nis the number of vertices of G, and has fractional cut covering number at most 1.127752. The lower bound on the size of maximum edge‐cut also applies to random cubic graphs. Specifically, a random n‐vertex cubic graph a.a.s. contains an edge‐cut of size 1.33008n‐ o(n). © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 2012
Transport layer enhancements on a satellite‐based mobile broadband system for high‐speed trains
Authors: Luglio Michele , Roseti Cesare , Zampognaro Francesco 
Published: September 2012

SUMMARYThe great diffusion of wireless portable and handheld devices, along with the growing availability of applications on the Internet, led to a significant increase in the demand of access. Users require to continue business or private activities when moving, with performance at least comparable with that experienced over fixed networks. A very interesting scenario encompasses broadband and uninterrupted access over high‐speed trains. Developments of new telecommunication standards as well as innovative network architectures give the potential to fully match the aforementioned requirements. Nevertheless, there is a significant number of issues, especially related to system integration, mobility management, and propagation channel conditions, that need a careful analysis with the aim to support the design of real systems. This paper deals with this challenging scenario proposing a satellite‐based architecture in which DVB‐S2 and DVB‐RCS standards, MIPv6 at layer 3 (for handover management), and an enhanced TCP version at layer 4, named TCP Noordwijk, allow to achieve good performance. An NS‐2 enhanced simulator has supported the whole analysis. Results show the effectiveness of the proposed scheme against different modulation and coding configurations and compared with a selected set of TCP‐enhanced versions. Copyright © 2012 John Wiley & Sons, Ltd.
Empirical assessment of methods for risk identification in healthcare data: results from the experiments of the Observational Medical Outcomes Partnership
Authors: Ryan Patrick B. , Madigan David , Stang Paul E. , Marc Overhage J. , Racoosin Judith A. , Hartzema Abraham G. 
Published: September 2012

Background: Expanded availability of observational healthcare data (both administrative claims and electronic health records) has prompted the development of statistical methods for identifying adverse events associated with medical products, but the operating characteristics of these methods when applied to the real‐world data are unknown.Methods: We studied the performance of eight analytic methods for estimating of the strength of association‐relative risk (RR) and associated standard error of 53 drug–adverse event outcome pairs, both positive and negative controls. The methods were applied to a network of ten observational healthcare databases, comprising over 130 million lives. Performance measures included sensitivity, specificity, and positive predictive value of methods at RR thresholds achieving statistical significance of p < 0.05 or p < 0.001 and with absolute threshold RR > 1.5, as well as threshold‐free measures such as area under receiver operating characteristic curve (AUC).Results: Although no specific method demonstrated superior performance, the aggregate results provide a benchmark and baseline expectation for risk identification method performance. At traditional levels of statistical significance (RR > 1, p < 0.05), all methods have a false positive rate >18%, with positive predictive value <38%. The best predictive model, high‐dimensional propensity score, achieved an AUC  =  0.77. At 50% sensitivity, false positive rate ranged from 16% to 30%. At 10% false positive rate, sensitivity of the methods ranged from 9% to 33%.Conclusions: Systematic processes for risk identification can provide useful information to supplement an overall safety assessment, but assessment of methods performance suggests a substantial chance of identifying false positive associations. Copyright © 2012 John Wiley & Sons, Ltd.
Optimization‐based power management of a wind farm with battery storage
Authors: Borhan Hoseinali , Rotea Mario A. , Viassolo Daniel 
Published: September 2012

ABSTRACTThis paper presents an optimization‐based control strategy for the power management of a wind farm with battery storage. The strategy seeks to minimize the error between the power delivered by the wind farm with battery storage and the power demand from an operator. In addition, the strategy attempts to maximize battery life. The control strategy has two main stages. The first stage produces a family of control solutions that minimize the power error subject to the battery constraints over an optimization horizon. These solutions are parameterized by a given value for the state of charge at the end of the optimization horizon. The second stage screens the family of control solutions to select one attaining an optimal balance between power error and battery life. The battery life model used in this stage is a weighted Amp‐hour throughput model. The control strategy is modular, allowing for more sophisticated optimization models in the first stage or more elaborate battery life models in the second stage. The strategy is implemented in real time in the framework of model predictive control. Copyright © 2012 John Wiley & Sons, Ltd.
Virtual inertia for variable speed wind turbines
Authors: Zeni Lorenzo , Rudolph Andreas Jakob , Münster‐Swendsen Janus , Margaris Ioannis , Hansen Anca Daniela , Sørensen Poul 
Published: September 2012

ABSTRACTInertia provision for frequency control is among the ancillary services that different national grid codes will likely require to be provided by future wind turbines. The aim of this paper is analysing how the inertia response support from a variable speed wind turbine (VSWT) to the primary frequency control of a power system can be enhanced. Unlike fixed speed wind turbines, VSWTs do not inherently contribute to system inertia, as they are decoupled from the power system through electronic converters. Emphasis in this paper is on how to emulate VSWTs inertia using control of the power electronic converter and on its impact on the primary frequency response of a power system. An additional control for the power electronics is implemented to give VSWTs a virtual inertia, referring to the kinetic energy stored in the rotating masses, which can be released initially to support the system's inertia. A simple Matlab/Simulink model and control of a VSWT and of a generic power system are developed to analyse the primary frequency response following different generation losses in a system comprising VSWTs provided with virtual inertia. The possibility of substituting a 50% share of conventional power with wind is also assessed and investigated. The intrinsic problems related to the implementation of virtual inertia are illustrated, addressing their origin in the action of pitch and power control. A solution is proposed, which aims at obtaining the same response as for the system with only conventional generation. The range of wind speeds near the power limitation zone seems to be the most critical from a primary response point of view. The theoretical reasons behind this are elucidated in the paper. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of Vehicle Size on Pedestrian Injury Pattern and Severity: Prospective Study
Authors: AlEassa Essa M. , Eid Hani O. , Abu‐Zidan Fikri M. 
Published: September 2012

AbstractBackgroundThe type of injuries caused by sport utility vehicles may be different from those caused by small passenger cars. We studied prospectively the effects of the offending vehicle type and design on severity and pattern of pedestrian injuries.MethodsAll injured pedestrians admitted to the two major trauma centers of Al‐Ain city were studied prospectively during the period of April 2006 to October 2007. Patients were classified into two groups according to the offending vehicle type: small vehicle and sport utility vehicle. These two groups were compared regarding the distribution of injury and its severity.ResultsThe anatomical distribution of injury in a descending order were the lower extremities (56.3, 67 %), head (53.8, 57.1 %), face (37.5, 57.1 %), and upper extremities (32.5, 28.6 %) in small vehicle and sport utility vehicle groups, respectively. No significant statistical difference has been found between the two groups regarding the anatomical distribution and severity.ConclusionsThe vehicle size and design did not affect the anatomical injury distribution and severity in our setting. High‐impact speed may overcome the vehicle type when it comes to injury severity and pattern of distribution.
From overlooking to concealed: predator avoidance in an apex carnivore
Authors: Wam H. K. , Eldegard K. , Hjeljord O. 
Published: September 2012

Abstract
Many prey species select bed sites that reduce the risk of being caught off guard. We investigated bed sites used by an apex predator (gray wolf, Canis lupus) before and after individuals were approached by humans (N = 48 trials). On 9 out of 10 days, the unprovoked wolves rested at sites high in the terrain with a good overview (overlooking sites). After being approached, they resettled on more concealed sites lower in the terrain. Solitary yearlings used less overlooking sites than adults both before and after disturbance. The study provides experimental evidence that wolves’ behavioural response to approaching humans is analogous to predator avoidance in prey species.
An alternative mechanism for shade adaptation: implication of allometric responses of three submersed macrophytes to water depth
Authors: Fu Hui , Yuan Guixiang , Cao Te , Ni Leyi , Zhang Meng , Wang Shengrui 
Published: September 2012

AbstractAllometric scaling models describing size‐dependent biological relationships are important for understanding the adaptive responses of plants to environmental variation. In this study, allometric analysis was used to investigate the biomass allocation and morphology of three submerged macrophytes (Potamogeton maackianus, Potamogeton malaianus and Vallisneria natans) in response to water depth (1.0 and 2.5 m) in an in situ experiment. The three macrophytes exhibited different allometric strategies associated with distinct adjustments in morphology and biomass allocation in response to varying water depths. In deeper water, after accounting for the effects of plant size, P. maackianus and P. malaianus tended to enhance light harvesting by allocating more biomass to the stem, increasing shoot height and specific leaf area. V. natans tended to allocate more biomass to the leaf than to the basal stem (rosette), showing a higher leaf mass ratio and shoot height in deeper water. The three species decreased biomass allocation to roots as water depth increased. The main effect of water depth treatments was reduced light availability, which induced plastic shoot or leaf elongation. This shows that macrophytes have evolved responses to light limitation similar to those of terrestrial plants.
Generation of 656 nm coherent red-light by frequency-doubled
Nd:YLiF4/β-BaB2O4 laser for a compact
silver atoms optical clock
Authors: Loisel J.-P. , Topsu S. , Chassagne L. , Alayli Y. , Dahoo P.R. , Juncar P. 
Published: September 2012

We describe an efficient continuous-wave diode-pumped Nd:YLiF4 laser
oscillating on the σ-polarized
4F3/2-4I13/2
transition at λω = 1312 nm. With a simple
linear cavity laser, we reached an intracavity power of 310 W at λ = 1312
nm for 16 W of absorbed pump power
(λp ~ 806 nm). A 0.25 W of tunable
radiation (λ2ω = 656−658 nm) was obtained
by intracavity second-harmonic generation (SHG) with a 5 × 5 × 7
mm3β-BaB2O4 crystal. Up to 10 mW of
tunable single-frequency operation was observed using a 200 μm thin fused
silica intracavity solid etalon. The optimal waist for a maximum conversion efficiency has
been calculated theoretically using Boyd and Kleiman model. For the 1312–656 nm SHG, we
found a walk-off parameter B = 8.99 and an optimal waist of 25
μm. Comparing to the experimental measurement of the optimal waist, we
found a relative discrepancy of 2.84 × 10-2. This laser is dedicated to the
spectroscopic study of silver atoms trapped in a buffer-gas-free paraffin coated Pyrex
cell that will be used in a compact atomic optical clock.
Impact of radial external magnetic field on plasma deformation during contact opening in SF6 circuit breakers
Authors: Abbasi V , Gholami A , Niayesh K 
Published: September 2012

Abstract
A three-dimensional (3D) transient model is developed to investigate plasma current deformation driven by internal and external magnetic fields and their influences on arc stability in a circuit breaker. The 3D distribution of electric current density is obtained by solving the current continuity equation along with the generalized Ohm's law in the presence of an external magnetic field, while the magnetic field induced by the current flowing through the arc column is calculated by the magnetic vector potential equation. The applied external field imposes a rotational electromagnetic force on the arc and influences the plasma current deformation, which is discussed in this paper. In SF6 circuit breakers when gas interacts with the arc column, the fundamental equations such as Ampere's law, Ohm's law, turbulence model, transport equations of mass, momentum, and energy of plasma flow have to be coupled for analysing the phenomenon. The coupled interactions between the arc and the plasma flow are described within the framework of magnetohydrodynamic equations in conjunction with a K–ε turbulence model. Simulations are focused on sausage and kink instabilities in the plasma (these phenomena are related to the electromagnetic field distribution and define the plasma deformations). The 3D simulation reveals the relation between plasma current deformation and instability phenomena, which affects the arc stability during the operation. Plasma current deformation is a consequence of coupling between electromagnetic forces (resulting from internal and radial external magnetic fields) and the plasma flow that are described in the simulations.
The bubble to jetting transition mechanism of plasmas in NaNO3 solutions sustained by pulsed power
Authors: Hsieh An-hsuan , Chang Hung-wen , Hsu Cheng-che 
Published: September 2012

Abstract
Plasmas in NaNO3 solutions sustained by pulsed power with T
on = 10–500 µs are studied. With an applied voltage equal to or lower than 100 V, the bubble mode is observed. In this mode, bubbles, a few hundred μm in diameter, are formed and detached continuously at the electrode surface because of the buoyant force. An increase in the applied voltage to 125 V results in a bubble to jetting transition. When this transition occurs, bubbles with diameters smaller than 100 µm are formed and are rapidly jetted away continuously. The examination of various conditions shows that the transition occurs when the power and energy input simultaneously exceed critical values 4.4 × 10−3 ± 6 × 10−4 J and 45 ± 5 W, respectively, within T
on. Given the electrode surface area, this critical power is equivalent to a heat flux of 229 ± 25 MW m−2, which is close to the heat flux required, 223 MW m−2, for the occurrence of explosive vaporization reported in the literature. Such an observation strongly supports the hypothesis that the bubble to jetting transition is induced by the electrothermal effect.
Influence of Cooking Formulation on Flavor and Hydrophilic Oxygen Radical Absorption Capacity Values of Whole Grain Colored Rice
Authors: Bett‐Garber Karen L. , Lea Jeanne M. , Watson Michael A. , Champagne Elaine T. 
Published: September 2012

ABSTRACTWhole grain rice is rich in healthful polyphenolic compounds that can impart undesirable flavors. Rice is typically prepared with water and sometimes salt, oil, or both, which can influence flavor. This research examines the influences of cooking whole grain rice with salt, oil, or both on flavor and antioxidant capacity. Nine commercial rice samples (three brown, three red, and three black or purple) were cooked with water only, added salt (0.5%), oil (1.575% v/w), or salt with oil (same concentrations). Flavor was measured with descriptive flavor analysis, and antioxidant capacity was measured by the hydrophilic oxygen radical absorption capacity (H‐ORAC) method. The addition of salt and salt with oil significantly reduced bitter, waterlike/metallic, and astringent flavors, whereas corn/popcorn/buttery flavor was increased. Cooking formulation significantly affected more flavor attributes in black/purple and brown bran samples than in the red bran samples. Salt, oil, or both can be added to rice at cooking to modify taste with only slight effects on antioxidant benefits. Bran color significantly influences many flavor attributes as well as impacting H‐ORAC values.
First Report of Garlic Rust Caused by Puccinia allii on Allium sativum in Minnesota
Authors: Szabo L. J. , Mollov D. S. , Rosen C. 
Published: September 2012

High-quality garlic is an emerging crop grown in Minnesota for local markets, community supported agriculture, and select restaurants. In July 2010, Allium sativum cv. German Extra Hardy Porcelain plants showing foliar symptoms typical of rust infection were brought to the Plant Disease Clinic at the University of Minnesota by a commercial grower from Fillmore County, Minnesota. Infected leaves showed circular to oblong lesions (1 to 3 mm long), which ranged in color from yellow-orange (uredinia) to black (telia). Urediniospores collected from uredinia were globoid to ellipsoid, yellowish in color, and measured 18 ± 1 × 30 ± 2 μm with a wall thickness of 2.4 ± 0.5 μm. Teliospores were two celled, 18 ± 3 × 47 ± 10 μm, with a projected cross-sectional area (1) of 826 ± 87 μm2; cell walls were smooth, brown, 1.6 ± 0.3 μm (proximal cell) to 2.1 ± 0.5 μm (distal cell) thick, and 4.2 ± 0.8 μm at the apex. The pathogen was identified as Puccinia allii (2) and a sample was deposited in the U.S. National Fungus Collection (BPI 884132). DNA was extracted from infected leaf tissue and the nuclear ribosomal internal transcribed spacer region (ITS) and 5′ end of the large subunit (LS) was amplified and sequenced as described by Anikster et al. (1). The 1,257-bp sequence from the sample collected in Minnesota (GenBank Accession No. JX402206) was identical to ITS/LS sequence of a sample of P. allii collected from garlic in California (GenBank Accession No. AF511077), with the exception that MN sequence contained nine “A”s rather than 10 in the hyper-variable area at the 3′ end of the ITS region. P. allii has been shown to be a species complex comprising at least two different types, “leek type” and “garlic type” (1). Based on the ITS sequence and the projected cross-sectional area of the teliospores, the sample of P. allii from MN is consistent with the garlic type. Garlic rust occurred in localized foci late in the growing season and therefore did not cause significant loss to the 2010 crop. Reoccurrence of garlic rust was not reported in either 2011 or 2012 growing seasons in Minnesota. P. allii all but eliminated commercial garlic production in California in the late 1990s (1) and has the potential to cause significant negative impact to the emerging garlic crop in Minnesota. However, the epidemiology of garlic rust in the northern U.S. is not well understood and therefore predicting the risk of the Minnesota garlic crop to rust is difficult. References: (1) Y. Anikster et al. Phytopathology 94:569, 2004. (2) L. J. Szabo et al, Rust. Pages 41-44 in: Compendium of Onion and Garlic Diseases and Pests, Second Edition. H. F. Schwartz and S. K. Mohan, eds. APS Press, St. Paul, 2008.
Water distribution at local and landscape scales affects tree utilization by elephants in Chobe National Park, Botswana
Authors: Fullman Timothy Jon , Child Brian 
Published: September 2012

AbstractAfrican elephant distribution and impacts are influenced by water availability. This study investigates the formation of piospheres – gradients of vegetation degradation with increasing proximity to water – at local and landscape scales in Chobe National Park, Botswana. Thirty‐four plots record elephant impact on trees in a transect extending over 60 km from the Chobe River, differentiating between debarking and browsing on branches. Elephant utilization exhibits local patterns nested within a landscape‐level context. At a local scale, branch herbivory decreases with distance from water, while debarking first decreases and then increases again. At a landscape scale, regression and canonical correlation analyses show decreasing debarking with distance from the river. Surprisingly, branch herbivory increases with distance from river, except within the first 10 km where previous studies have focused. Elephant impact on vegetation is both more complex and extensive than previously assumed. Piosphere predictions are upheld at the local scale, with utilization decreasing with distance from water. This does not hold at the landscape scale, however, likely due to seasonal shifts in elephant distribution, diet and the presence of water in ephemeral pans. These findings have important implications for elephant management and emphasize the importance of looking across scales when assessing elephant impact.