bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of glass fiber‐multiwall carbon nanotube hybrid structures for high‐performance conductive composites
Authors: Jin Jie , Zhang Ling , Chen Wei , Li Chun‐Zhong
Published: June 2013

The conductive polyamide 66 (PA66)/carbon nanotube (CNT) composites reinforced with glass fiber‐multiwall CNT (GF‐MWCNT) hybrids were prepared by melt mixing. Electrostactic adsorption was utilized for the deposition of MWCNTs on the surfaces of glass fibers (GFs) to construct hybrid reinforcement with high‐electrical conductivity. The fabricated PA66/CNT composites reinforced with GF‐MWCNT hybrids showed enhanced electrical conductivity and mechanical properties as compared to those of PA66/CNT or PA66/GF/CNT composites. A significant reduction in percolation threshold was found for PA66/GF‐MWCNT/CNT composite (only 0.70 vol%). The morphological investigation demonstrated that MWCNT coating on the surfaces of the GFs improved load transfer between the GFs and the matrix. The presence of MWCNTs in the matrix‐rich interfacial regions enhanced the tensile modulus of the composite by about 10% than that of PA66/GF/CNT composite at the same CNT loading, which shows a promising route to build up high‐performance conductive composites. POLYM. COMPOS. 34:1313–1320, 2013. © 2013 Society of Plastics Engineers
Modeling the rheology of SR1500 and LY556 epoxies under manufacturer's recommended cure cycles after viscosimetry and rheometry characterization
Authors: Faria Hugo , Pires F.M. Andrade , Marques A. Torres
Published: June 2013

The evolution of the viscosity of two commercial epoxy resin systems subjected to manufacturer's recommended cure cycles was studied in detail. The two systems were characterized through rotational viscosimetry and oscillatory rheometry. It was observed that the different size of the samples in the two setups influenced the kinetics and, thus, the evolution of the cure and viscosity. The differences resided in the effective temperature experienced by the resin at each moment. Original rheological constitutive relations are proposed for each resin system and mass quantity, aiming to capture the “real” processing conditions. All the experimental and modeling procedures are described in detail and the new rheological constitutive relations are presented. POLYM. ENG. SCI., 54:831–839, 2014. © 2013 Society of Plastics Engineers
Patient Satisfaction with Services Provided by Multidisciplinary Anticoagulation Clinics
Authors: Bungard Tammy J. , Barry Arden R. , Jones Cindy , Brocklebank Cynthia
Published: June 2013

Study Objective

To assess patients' perception of care delivery by anticoagulation clinics (ACs) throughout Alberta, Canada.

Design

Prospective postal survey.

Setting

Therapy provision by an AC to ambulatory‐based patients for a minimum of 3 months across the province.

Patients

A total of 1687 patients (67.9%) receiving warfarin therapy from 6 ACs for a minimum of 3 months responded.

Measurement and Main Results

The 25‐item survey had responses grouped into domains of patient preference, knowledge, and service delivery. A 5‐point Likert scale enabled each response to be assigned a numerical value from 1 (strongly disagree) to 5 (strongly agree). Overall, the mean response for patient satisfaction was 4.54, indicating most patients were satisfied with the AC care they received. Among those who had received care outside of an AC, 70.4% preferred AC care compared with 18.4% for family physician care. Mean responses for knowledge and service delivery exceeded 4.0, demonstrating positive responses in favor of AC care.

Conclusions

This study demonstrates that most patients were greatly satisfied with AC care and preferred the care received from an AC to that provided by their family physician. Service delivery across Alberta is well perceived by patients.
Fluorescence enhancement effect in pyrene and perylene doped nanoporous polystyrene films: Mechanistic and morphology
Authors: Desai N. K. , Gupta M. K. , Kolekar G. B. , Patil S. R.
Published: June 2013

Luminescent porous polystyrene (PS) films containing pyrene and various amounts of perylene were prepared in humid atmosphere by solution casting technique for use as a plastic scintillator. The fluorescence spectra of doped PS films monitored at pyrene excitation show quenching of monomer fluorescence of pyrene with simultaneous sensitization of perylene monomer fluorescence appearing towards red. The observed enhancement in fluorescence of perylene was explained by considering excitation energy transfer (EET) from pyrene to perylene molecules accommodated in the pores generated during film formation. The fluorescence quenching data do not fit into the Stern–Volmer relation, but the sensitized fluorescence is fitted by an exponential growth equation, y = 201 860 433.29 ex/0.64366 + 0.49262, with correlation coefficient R2 = 0.997. The results on absorption and excitation spectroscopy indicated that the pyrene and perylene filled in pores of the PS films exist as isolated molecules. The porosity of the films was examined by atomic force microscopy (AFM) and scanning electron microscopy (SEM), showing randomly oriented holes, and their mean size and size distribution were found to be depending upon the dopant concentration.

Pyrene and perylene doped porous PS films prepared by solution casting method in humid atmosphere showed highly intense blue perylene fluorescence by fluorescence resonance energy transfer (FRET) at pyrene excitation. The SEM and AFM images revealed that nanosized pores are perylene concentration dependent, both pyrene and perylene held in the cavity of the pores in close proximal distance less than 10 nm is required to cause efficient energy transfer between them.
Composition dependence of the optical constants of amorphous (Se80Te20)100−xAgx (0 ≤ x ≤ 4) films
Authors: Singh D. , Kumar S. , Anand K. , Thangaraj R.
Published: June 2013

This paper reports the influence of silver (Ag) addition on the optical constants of chalcogenide (Se80Te20)100−xAgx (0 ≤ x ≤ 4) thin films. Films of (Se80Te20)100−xAgx (0 ≤ x ≤ 4) glasses were prepared by thermal evaporation of the bulk samples. The transmittance and reflection spectra of amorphous thin films were obtained in the spectral region in the range 400–2500 nm. The optical band gap and the absorption coefficient were calculated from the transmission and reflection data. Swanepoel method has been applied to derive the real and imaginary parts of the complex index of refraction, refractive index, and also the thickness of amorphous films. The dispersion parameters are calculated by using the Wemple–DiDomenico model. The optical constants, i.e., the refractive index, extinction coefficient, absorption coefficient, and optical band gap are determined and their compositional dependence is considered. The results are discussed on the basis of defects and disorders present in chalcogenide systems.
Periodicities in Saturn's magnetosphere
Authors: Carbary J. F. , Mitchell D. G.
Published: June 2013

Although the exact rotation period of Saturn is unknown, Saturn's magnetosphere displays an abundance of periodicities near ~10.7 h. Such modulations appear in charged particles, magnetic fields, energetic neutral atoms, radio emissions, motions of the plasma sheet and magnetopause, and even in Saturn's rings themselves. Known to an accuracy of four significant figures, these periodicities do not remain constant but vary by ~1% over time scales of a year or longer. Magnetospheric periodicities also display slightly different periods in the northern and southern hemispheres: ~10.6 h and ~10.8 h, respectively. The magnetic and spin axes of Saturn are aligned to within ~1°, so that Saturn's magnetospheric periodicities cannot be explained as “wobble” caused by a geometric tilt, unlike those of the Earth and Jupiter. Furthermore, the variations in periodicity argue against a cause related to changes interior to an object as large as Saturn. Several models have been proposed for the periodicities, including rotating planetary vortices, periodic plasma releases, and a flapping magnetodisk, but none can satisfactorily explain all of Saturn's periodicities. This review discusses the observations of these periodicities from their initial discovery during the Pioneer flyby to their long‐term surveillance by Cassini and examines the various struggles to explain and model them. Understanding Saturn's periodicity may elucidate periodic phenomena in other magnetospheric environments.
Semiempirical and process‐based global sea level projections
Authors: Moore John C. , Grinsted Aslak , Zwinger Thomas , Jevrejeva Svetlana
Published: June 2013

We review the two main approaches to estimating sea level rise over the coming century: physically plausible models of reduced complexity that exploit statistical relationships between sea level and climate forcing, and more complex physics‐based models of the separate elements of the sea level budget. Previously, estimates of future sea level rise from semiempirical models were considerably larger than those from process‐based models. However, we show that the most recent estimates of sea level rise by 2100 using both methods have converged, but largely through increased contributions and uncertainties in process‐based model estimates of ice sheets mass loss. Hence, we focus in this paper on ice sheet flow as this has the largest potential to contribute to sea level rise. Progress has been made in ice dynamics, ice stream flow, grounding line migration, and integration of ice sheet models with high‐resolution climate models. Calving physics remains an important and difficult modeling issue. Mountain glaciers, numbering hundreds of thousands, must be modeled by extensive statistical extrapolation from a much smaller calibration data set. Rugged topography creates problems in process‐based mass balance simulations forced by regional climate models with resolutions 10–100 times larger than the glaciers. Semiempirical models balance increasing numbers of parameters with the choice of noise model for the observations to avoid overfitting the highly autocorrelated sea level data. All models face difficulty in separating out non‐climate‐driven sea level rise (e.g., groundwater extraction) and long‐term disequilibria in the present‐day cryosphere‐sea level system.
Residual plots for repeated measures
Authors: Weiss Robert E. , Lazaro Carlos G.
Published: June 2013

Multivariate data are difficult to analyse partly because of difficulty in looking at the data. Repeated measures data have a special structure that makes the parallel plot1,2 particularly effective for viewing the data. In this paper we use parallel plots to display not just raw data but also residuals from standard models fit to repeated measures data. The plots are useful for determining how well a particular model fits the data, identifying outlying observations and suggesting terms missing from the linear predictor.
An Initial Experience with Hip Resurfacing versus Cementless Total Hip Arthroplasty
Authors: Arndt Justin Michael , Wera Glenn D. , Goldberg Victor M.
Published: June 2013

Background

Hip resurfacing is an alternative to total hip arthroplasty.

Questions/Purpose

We aimed to compare an experienced hip surgeon's initial clinical results of hip resurfacing with a new cementless total hip arthroplasty (THA).

Methods

The first 55 consecutive hip resurfacing arthroplasties were compared to 100 consecutive cementless THAs using a cylindrical tapered femoral stem. The learning curve between the two procedures was compared utilizing the incidence of reoperation, complications, Harris Hip Scores (HHS), and implant survivorship.

Results

The reoperation rate was significantly higher ( p = 0.019) for hip resurfacing (14.5%) versus THA (4%). The overall complication rate between the two groups was not significantly different ( p = 0.398). Preoperative HHS were similar between the two groups ( p = 0.2). The final mean HHS was similar in both the resurfacing and THA groups (96 vs. 98.3, respectively, p < 0.65). Kaplan–Meier survival analysis with an endpoint of reoperation suggests complications occurred earlier in the resurfacing group versus the THA group (log-rank test, p = 0.007).

Conclusions

In comparison to our initial experience with a cementless THA stem, operative complications occur earlier and more often after hip resurfacing during the learning period. The clinical outcomes in both groups however are similar at 5 year follow-up.
Mental Health is Central to Good Neurorehabilitation after TBI
Authors: Fleminger Simon
Published: June 2013

Those after traumatic brain injury (TBI) who suffer mental health problems, by which I mean problems that a psychiatrist might understand as falling within their remit, suffer a double whammy. Not only do they suffer the stigma of the disabled, but even within this group they may be stigmatised. It has often been my experience that while families will allow for their injured loved one to be under the care of rehabilitation services, including a psychologist, they baulk at the possibility that their loved one may need psychiatric care. This comes to a head when it comes to detaining a patient, in England and Wales, under the Mental Health Act; this may be vigorously resisted by family because of what they infer this says about their loved one's sanity.
Locomotion over a viscoplastic film
Authors: Pegler Samuel S. , Balmforth Neil J.
Published: June 2013

We present a modelling study of locomotion over a layer of viscoplastic fluid motivated by the self-propulsion of marine and terrestrial gastropods. Our model comprises a layer of viscoplastic mucus lying beneath a fluid-filled foot that is laced internally by muscular fibres under tension and overlain by the main body of the locomotor, which is assumed to be rigid. The mucus is described using lubrication theory and the Bingham constitutive law, and the foot using a continuum approximation for the action of the muscle fibres. The model is first used to study the retrograde strategy of locomotion employed by marine gastropods, wherein the muscle fibres create a backwards-travelling wave of predominantly normal displacements along the surface of the foot. Once such a retrograde forcing pattern is switched on, the system is shown to converge towards a steady state of locomotion in a frame moving with the wave. The steady speed of locomotion decreases with the yield stress, until it vanishes altogether above a critical yield stress. Despite the absence of locomotion above this threshold, waves still propagate along the foot, peristaltically pumping mucus in the direction of the wave. The model is next used to study the prograde strategy employed by terrestrial gastropods, wherein the muscle fibres create a forwards-travelling wave of predominantly tangential displacements of the foot surface. In this case, a finite yield stress is shown to be necessary for locomotion, with the speed of locomotion initially increasing with the yield stress. Beyond a critical yield stress, localized rigid plugs form across the depth of the mucus layer, adhering parts of the foot to the base. These stop any transport of mucus, but foot motions elsewhere still drive locomotion. As the yield stress is increased further, the rigid plugs widen horizontally, increasing the viscous drag and eventually reducing the speed of locomotion, which is therefore maximized for an intermediate value of the yield stress.
Thixotropic gravity currents
Authors: Hewitt Duncan R. , Balmforth Neil J.
Published: June 2013

We present a model for thixotropic gravity currents flowing down an inclined plane that combines lubrication theory for shallow flow with a rheological constitutive law describing the degree of microscopic structure. The model is solved numerically for a finite volume of fluid in both two and three dimensions. The results illustrate the importance of the degree of initial ageing and the spatio-temporal variations of the microstructure during flow. The fluid does not flow unless the plane is inclined beyond a critical angle that depends on the ageing time. Above that critical angle and for relatively long ageing times, the fluid dramatically avalanches downslope, with the current becoming characterized by a structured horseshoe-shaped remnant of fluid at the back and a raised nose at the advancing front. The flow is prone to a weak interfacial instability that occurs along the border between structured and de-structured fluid. Experiments with bentonite clay show broadly similar phenomenological behaviour to that predicted by the model. Differences between the experiments and the model are discussed.
Outer-layer turbulence intensities in smooth- and rough-wall boundary layers
Authors: Castro Ian P. , Segalini Antonio , Alfredsson P. Henrik
Published: June 2013

Clear differences in turbulence intensity profiles in smooth, transitional and fully rough zero-pressure-gradient boundary layers are demonstrated, using the diagnostic plot introduced by Alfredsson, Segalini & Örlü (Phys. Fluids, vol. 23, 2011, p. 041702) – ${u}^{\prime } / U$ versus $U/ {U}_{e} $, where ${u}^{\prime } $ and $U$ are the local (root mean square) fluctuating and mean velocities and ${U}_{e} $ is the free stream velocity. A wide range of published data are considered and all zero-pressure-gradient boundary layers yield outer flow ${u}^{\prime } / U$ values that are roughly linearly related to $U/ {U}_{e} $, just as for smooth walls, but with a significantly higher slope which is completely independent of the roughness morphology. The difference in slope is due largely to the influence of the roughness parameter ($ \mathrm{\Delta} {U}^{+ } $ in the usual notation) and all the data can be fitted empirically by using a modified form of the scaling, dependent only on $ \mathrm{\Delta} U/ {U}_{e} $. The turbulence intensity, at a location in the outer layer where $U/ {U}_{e} $ is fixed, rises monotonically with increasing $ \mathrm{\Delta} U/ {U}_{e} $ which, however, remains of $O(1)$ for all possible zero-pressure-gradient rough-wall boundary layers even at the highest Reynolds numbers. A measurement of intensity at a point in the outer region of the boundary layer can provide an indication of whether the surface is aerodynamically fully rough, without having to determine the surface stress or effective roughness height. Discussion of the implication for smooth/rough flow universality of differences in outer-layer mean velocity wake strength is included.
New species and additional records of Coenogonium (Ostropales: Coenogoniaceae) from southern South America
Authors: FERRARO Lidia I. , MICHLIG Andrea
Published: June 2013

Four new species of lichenized fungi from northern Argentina are described and illustrated: Coenogonium albomarginatum Michlig & L. I. Ferraro, C. brasiliense L. I. Ferraro & Michlig, C. flavovirens L. I. Ferraro & Michlig, and C. verrucosum Michlig & L. I. Ferraro. In addition, C. isidiatum (G. Thor & Vězda) Lücking et al., C. magdalenae Rivas Plata, Lücking & Lizano, C. persistens (Malme) Lücking et al., C. pusillum (Mont.) Lücking et al., and C. weberi (Vězda) Lücking et al. are recorded for the first time from South America. The known distribution of 24 species of this lichen genus is extended. A revision of the genus in Argentina and Paraguay is also presented.
Cascading and feedback in interactive models of production: A reflection of forward modeling?
Authors: Dell Gary S.
Published: June 2013

Interactive theories of lexical retrieval in language production assume that activation cascades from earlier to later processing levels, and feeds back in the reverse direction. This commentary invites Pickering & Garrod (P&G) to consider whether cascading and feedback can be seen as a form of forwarding modeling within a hierarchical production system.
Memory and cognitive control in an integrated theory of language processing
Authors: Slevc L. Robert , Novick Jared M.
Published: June 2013

Pickering & Garrod's (P&G's) integrated model of production and comprehension includes no explicit role for nonlinguistic cognitive processes. Yet, how domain-general cognitive functions contribute to language processing has become clearer with well-specified theories and supporting data. We therefore believe that their account can benefit by incorporating functions like working memory and cognitive control into a unified model of language processing.
Are forward models enough to explain self-monitoring? Insights from patients and eye movements
Authors: Hartsuiker Robert J.
Published: June 2013

At the core of Pickering & Garrod's (P&G's) theory is a monitor that uses forward models. I argue that this account is challenged by neuropsychological findings and visual world eye-tracking data and that it has two conceptual problems. I propose that conflict monitoring avoids these issues and should be considered a promising alternative to perceptual loop and forward modeling theories.
Predictive coding? Yes, but from what source?
Authors: Hickok Gregory
Published: June 2013

There is little doubt that predictive coding is an important mechanism in language processing–indeed, in information processing generally. However, it is less clear whether the action system is the source of such predictions during perception. Here I summarize the computational problem with motor prediction for perceptual processes and argue instead for a dual-stream model of predictive coding.
Malmö diskont 1817: an institutional analysis of a banking crisis
Authors: Kärrlander Tom
Published: June 2013

Malmö diskont, a Swedish bank, was forced to close in 1817 after 14 years of operation because of a bank run. At the time, it was one of only three private commercial banks in Sweden. Eventually, all three banks succumbed to bank runs. The purpose of this article is to study the 1817 banking crisis from a new perspective by attempting to answer the following research question: why did Malmö diskont go under? Institutional theory is used here as a research tool. The assumption is that institutions set the limits for individuals' actions and sometimes direct them towards particular actions. The conclusions are derived from analysing the institutional framework at the time and how it interacted with Malmö diskont. The crisis evolved in two stages. The first stage occurred when the financial position of Malmö diskont severely deteriorated in the interaction between institutions and actors in 1817. The implementation of a bailout and a new institutional structure would have been necessary to save the bank. This conclusion complements earlier theories related to monetary or credit overexpansion as to why banking crises occur. The second stage occurred when the Swedish government allowed Malmö diskont to fall in October 1817.
Circulating levels of the cytokines IL10, IFNγ and resistin in an obese mouse model of developmental programming
Authors: Kępczyńska M. A. , Wargent E. T. , Cawthorne M. A. , Arch J. R. S. , O'Dowd J. F. , Stocker C. J.
Published: June 2013

An infant's early developmental environment plays a pivotal role in the programming of its physiological phenotype. The identification of the factors in the maternal environment that mediate the effects of maternal obesity and diet is essential to the development of clinical intervention strategies. Maternal hyperglycaemia, hyperinsulinaemia, hypertriglyceridaemia, hyperleptinaemia and altered inflammatory cytokines concentrations are potentially important predictive factors of her future offspring's susceptibility to metabolic disease. Using a diet-induced obese mouse model, we have investigated which of these maternal factors could induce adverse metabolic programming in the offspring. Female C57Bl/6 mice were fed either laboratory chow (10% fat) or high fat diet (42% fat) for 10 weeks before mating and throughout gestation. At day 18 of pregnancy, maternal body weight, body composition and glucose tolerance were measured, as well as plasma insulin, adiponectin, RBP4, leptin, resistin and the inflammatory cytokines (IL6, IL10, IL12, IL1β, IFNγ, KC, TNF-α). At day 18 of pregnancy, high fat-fed dams were significantly heavier than the chow dams and had increased fat mass. High fat-fed dams had higher 5 h fasting blood glucose than chow dams and elevated plasma insulin. Although the obese dams had both reduced plasma adiponectin and resistin levels compared with lean dams, their plasma IL6, IL10 and IFNγ levels were all increased. High fat feeding in pregnancy leads to altered plasma concentrations of both adipokines and adipocytokines in the dam that may directly pass to the fetus and affect their development.
China's Implementation of Alternatives Assessment in the Building Industry: GIGA
Authors: Zang Brandon , Wallis Raefer K. , Dick Ryan D.
Published: June 2013

China has been known as the world's factory for decades. It is synonymous with cheap goods, heavy pollution, copyright infringement and innumerable breaches of trust. Despite its infamous recent history, this chapter explores how China is poised to become a global leader in the demand for the assessment of chemical alternatives. In order to understand how the world's most populous country can undergo this radical transformation, one must understand its cultural history and drivers of change. This chapter begins with China's long relationship with personal health and explains the impact of newly found wealth and access to information. It continues by exploring how the combination of social media and China's tenuous relationship with trust can move the demand for chemicals assessment into the hands of everyday consumers. Finally, it ends by giving an example of how these lessons are being applied locally through an online platform.

It is important to note that the authors of this chapter are neither toxicologists nor pioneers in the development of green chemistry. Rather, they are architects and chemists who have spent the past four and a half years researching and implementing ways to create demand for green chemistry and alternatives assessment. This chapter is not a scientific piece, but rather a report on how the authors are attempting to harness developments and trends in both the IT and building industries to support research in the assessment of chemical alternatives.
Alternatives Assessment in Regulatory Policy: History and Future Directions
Authors: Tickner J. A. , Geiser K. , Rudisill C. , Schifano J. N.
Published: June 2013

As the use of alternatives assessment as a tool to support the adoption of safer chemicals continues to evolve, the role of government in forming successful policies and initiatives needs thoughtful analysis. Although many chemical policies restricting or phasing out chemicals exist, very few mandate alternatives assessment or have adequate frameworks or tools to support successful implementation while avoiding regrettable substitutions. This chapter explores the justification and rationale for requiring alternatives assessment in the formation of chemical policies that support ‘informed substitution.’ A historical and current overview of chemical restriction and alternatives assessment policies is then provided and also a typology of current policies and initiatives that require or incentivize alternatives assessments. Five case studies highlighting regulatory policies requiring alternatives assessments, along with other examples, are used to support several lessons learned for future government policies that support informed substitution. Taken together, these policies illustrate that (1) there is a need for policies that require alternatives assessment, (2) carefully designed incentives and disincentives can encourage adoption safer alternatives, (3) alternatives assessment requirements should be tied to initiatives that incentivize adoption of safer alternatives and (4) there is a need for clear, yet flexible guidance and criteria for alternatives assessment processes. Although alternatives assessment requirements are necessary, it is critical that they not become overly prescriptive, burdensome or scientized in a way that inhibits their ability to achieve the goal of safer chemistry.
Wind turbine converter control interaction with complex wind farm systems
Authors: Kocewiak Łukasz Hubert , Hjerrild Jesper , Bak Claus Leth
Published: June 2013

This study presents wind turbine converter stability analysis of wind farms in frequency domain. The interaction between the wind turbine control system and the wind farm structure in wind farms is deeply investigated. Two wind farms (i.e. Horns Rev II and Karnice) are taken into consideration in this study. It is shown that wind farm components, such as long high‐voltage alternating current cables and park transformers, can introduce significant low‐frequency series resonances seen from the wind turbine terminals that can affect wind turbine control system operation and overall wind farm stability. The same wind turbine converter control strategy is evaluated in two different wind farms. It is emphasised that the grid‐side converter controller should be characterised by sufficient harmonic/noise rejection and adjusted depending on wind farms to which it is connected. Various stability indices such as gain margin, vector gain margin and phase margin are used in order to emphasise the differences between the two wind farms.
Un‐freezing the turbulence: application to LiDAR‐assisted wind turbine control
Authors: Bossanyi Ervin
Published: June 2013

Recent developments in LiDAR technology have led to much interest in the possibility of improving turbine control by using a turbine‐mounted LiDAR, to provide advance information about the approaching wind field. This could significantly reduce turbine loads, bringing improved cost‐effectiveness, especially for large turbines. There have also been claims of direct increases in energy capture as a result of using such preview information. This study reports on an independent study employing detailed analytical methods to evaluate the likely benefits of LiDAR‐assisted control and advise LiDAR manufacturers about the characteristics of their systems, which are most likely to be useful for this application. Accurate simulation models are vital for assessing the performance of LiDARs and controllers which use them. Current models use Taylor's frozen turbulence hypothesis, but this is not strictly valid when LiDAR is used to measure upstream wind speeds, as the measured wind cannot be assumed to convect unchanged to the turbine. A method for avoiding the frozen turbulence assumption is proposed, and simulation results are presented to illustrate the effect on fatigue load reductions which LiDAR‐assisted control might achieve. A detailed assessment of possible LiDAR benefits is made using the UPWIND generic 5 MW turbine as an example.
Analysis of electrical power data for condition monitoring of a small wind turbine
Authors: Barton John P. , Watson Simon J.
Published: June 2013

Certain parts of a wind turbine, for example, the gearbox require significant time and heavy lifting equipment in the event of catastrophic failure necessitating replacement. Continuous condition monitoring has the potential to catch problems early, enable scheduled preventative maintenance and thereby reduce turbine downtime, reduce the number of site visits and prevent secondary damage. Accelerometers applied to mechanical components of the drive train are traditionally used for condition monitoring, but require their own data acquisition system and analysis software. In contrast, the electrical current and voltage are continuously measured and could also be used for condition monitoring more cheaply. An experimental data acquisition system has been installed on a small (25 kW) onshore turbine in Leicestershire, UK to compare three‐phase currents and voltages on the stator windings with six accelerometer signals. Data have been recorded before and after a gearbox failure and replacement. Data were analysed using both Fourier transform and Morlet continuous wavelet transform methods. Results show that the stator voltages show the same radial and axial mode vibration frequencies as the accelerometers, and could therefore be used for condition monitoring. Furthermore, the stator currents show torsional modes of vibration not picked up by the accelerometers.
Wideband microstrip‐line‐fed hexagonal slot antenna for WiMAX and wireless local area network applications
Authors: Chattopadhyay Krishnendu , Roy Choudhury Somdotta , Das Santanu , Bhadra Chaudhuri Sekhar Ranjan
Published: June 2013

A wideband microstrip‐line‐fed hexagonal wide‐slot antenna is proposed and experimentally investigated. The hexagonal slot excited by a simple 50 Ω microstrip line with a rotation angle of 0° having 470 MHz bandwidth is considered as a reference antenna. The proposed hexagonal slot is rotated by 30° and excited by a 50 Ω line loaded by a hexagonal tuning stub. The experimental results exhibit matching impedance below a 2:1 VSWR bandwidth of 5165 MHz (2.117–7.282 GHz) covering all the WiMAX and wireless local area network band applications, which is about 110% w.r.t. a centre frequency of 4699.5 MHz. The impedance, radiation and gain characteristics of the proposed configuration are studied and the results are exhibited accordingly.
Role of electronic correlation in high-low temperature phase transition of hexagonal nickel sulfide: A comparative density functional theory study with and without correction for on-site Coulomb interaction
Authors: Zhang Wei-Bing , Li Jie , Tang Bi-Yu
Published: June 2013

The structural, electronic, magnetic, and elastic properties of hexagonal nickel sulfide (NiS) have been investigated comparatively by Density Functional theory (DFT) and DFT plus correction for on-site Coulomb interaction (DFT+U), in which two different exchange correlation functionals local density approximations (LDA) and general gradient approximations (GGA) in the form of Perdew-Burke-Ernzerhof (PBE) are used. Our results indicate LDA and PBE methods predict hexagonal NiS to be a paramagnetic metal whereas LDA(PBE)+U calculations with reasonable on-site Coulomb interaction energy give the antiferromagnetic insulating state of low temperature hexagonal NiS successfully. Meanwhile, compared with LDA(PBE) results, LDA(PBE)+U methods give larger lattice parameters, crystal volume, and shear constant c44, consistent with the experimental picture during high-low temperature phase transition of hexagonal NiS, in which an increase of the shear constant c44 and lattice parameters were found in the low-temperature antiferromagnetic phase. The present DFT and DFT+U calculations provide a reasonable description for the properties of high temperature and low temperature hexagonal NiS respectively, which indicates that electronic correlation is responsible for this high-low temperature phase transition.
Identification of vortexes obstructing the dynamo mechanism in laboratory experiments
Authors: Limone A. , Hatch D. R. , Forest C. B. , Jenko F.
Published: June 2013

The magnetohydrodynamic dynamo effect explains the generation of self-sustained magnetic fields in electrically conducting flows, especially in geo- and astrophysical environments. Yet the details of this mechanism are still unknown, e.g., how and to which extent the geometry, the fluid topology, the forcing mechanism, and the turbulence can have a negative effect on this process. We report on numerical simulations carried out in spherical geometry, analyzing the predicted velocity flow with the so-called singular value decomposition, a powerful technique that allows us to precisely identify vortexes in the flow which would be difficult to characterize with conventional spectral methods. We then quantify the contribution of these vortexes to the growth rate of the magnetic energy in the system. We identify an axisymmetric vortex, whose rotational direction changes periodically in time, and whose dynamics are decoupled from those of the large scale background flow, that is detrimental for the dynamo effect. A comparison with experiments is carried out, showing that similar dynamics were observed in cylindrical geometry. These previously unexpected eddies, which impede the dynamo effect, offer an explanation for the experimental difficulties in attaining a dynamo in spherical geometry.
Nanoclusters of MoO3−x embedded in an Al2O3 matrix engineered for customizable mesoscale resistivity and high dielectric strength
Authors: Tong William M. , Brodie Alan D. , Mane Anil U. , Sun Fuge , Kidwingira Françoise , McCord Mark A. , Bevis Christopher F. , Elam Jeffrey W.
Published: June 2013

We have synthesized a material consisting of conducting metal oxide (MoO3−x) nanoclusters embedded in a high-dielectric-strength insulator (Al2O3) matrix. The resistivity of this material can be customized by varying the concentration of the MoO3−x nanoclusters. The Al2O3 protects the MoO3−x from stoichiometry change, thus conserving the number of carriers and maintaining a high dielectric strength. This composite material is grown by atomic layer deposition, a thin film deposition technique suitable for coating 3D structures. We applied these atomic layer deposition composite films to our 3D electron-optical micro electrical mechanical systems devices and greatly improved their performance.
Scanning AC nanocalorimetry combined with in-situ x-ray diffraction
Authors: Xiao Kechao , Gregoire John M. , McCluskey Patrick J. , Dale Darren , Vlassak Joost J.
Published: June 2013

Micromachined nanocalorimetry sensors have shown excellent performance for high-temperature and high-scanning rate calorimetry measurements. Here, we combine scanning AC nanocalorimetry with in-situ x-ray diffraction (XRD) to facilitate interpretation of the calorimetry measurements. Time-resolved XRD during in-situ operation of nanocalorimetry sensors using intense, high-energy synchrotron radiation allows unprecedented characterization of thermal and structural material properties. We demonstrate this experiment with detailed characterization of the melting and solidification of elemental Bi, In, and Sn thin-film samples, using heating and cooling rates up to 300 K/s. Our experiments show that the solidification process is distinctly different for each of the three samples. The experiments are performed using a combinatorial device that contains an array of individually addressable nanocalorimetry sensors. Combined with XRD, this device creates a new platform for high-throughput mapping of the composition dependence of solid-state reactions and phase transformations.
Multi-field nanoindentation apparatus for measuring local mechanical properties of materials in external magnetic and electric fields
Authors: Zhou Hao , Pei Yongmao , Huang Hu , Zhao Hongwei , Li Faxin , Fang Daining
Published: June 2013

Nano/micro-scale mechanical properties of multiferroic materials can be controlled by the external magnetic or electric field due to the coupling interaction. For the first time, a modularized multi-field nanoindentation apparatus for carrying out testing on materials in external magnetostatic/electrostatic field is constructed. Technical issues, such as the application of magnetic/electric field and the processes to diminish the interference between external fields and the other parts of the apparatus, are addressed. Tests on calibration specimen indicate the feasibility of the apparatus. The load-displacement curves of ferromagnetic, ferroelectric, and magnetoelectric materials in the presence/absence of external fields reveal the small-scale magnetomechanical and electromechanical coupling, showing as the ΔE and ΔHin effects, i.e., the magnetic/electric field induced changes in the apparent elastic modulus and indentation hardness.
Physical suppression effects of the reversed magnetic coupling on the saturation inductance of saturable pulse transformer
Authors: Zhang Yu , Liu Jinliang
Published: June 2013

As a combination device of pulse transformer and magnetic switch, saturable pulse transformer (SPT) is widely employed in high power laser pumping and pulsed power technology. A reversed magnetic coupling mechanism of the diverging magnetic fields among multiple windings is put forward to explain the physical suppression effect on the saturation inductance of the SPT windings. The theoretical and experimental results reveal that the saturation inductance of the SPT can decrease to a level less than its structural inductance through regulating the reversed currents in the multiple windings, which helps to achieve a magnetic switch with ultra-low saturation inductance.
The politics of language in a deeply divided society
Authors: Southern Neil
Published: June 2013

Language plays an important role in fashioning the identity of ethnic groups. This article explores a minority language – Irish – in Northern Ireland. Given the society’s longstanding ethnic divisions, matters revolving around the Irish language are capable of generating heated debate. However, unlike some other minority languages, Irish is somewhat peculiar in that it is not used as a form of linguistic communication between speakers on a daily basis. Hence it lacks instrumental (but not symbolic) relevance in this sense and supporters of the language can be observed trying to create rather than maintain a community of speakers. This fact sets Irish apart from some other minority languages which have generated emotive political debate, for example, Afrikaans in South Africa and French in Canada. The article considers the language debate that has emerged in Northern Ireland in the light of such factors.
Ideologically speaking
Authors: Krizsán Attila
Published: June 2013

This paper offers a politolinguistic analysis of four ‘state of the nation’ speeches delivered by the Hungarian Prime Minister Viktor Orbán between 1999 and 2002. The analysis focuses on the ways in which Orbán’s self-representation, his discourse strategies and the tone of the speeches changed in response to changes in the ideological background over the four years in question. The findings demonstrate that Orbán’s voice was most active in the pre-election speech of 2002, that he had become increasingly interpellative (in the Althusserian sense) over this period and that he increasingly tried to conversationalize the dominant ideology.
“Mutual understanding” in Tatarstan?
Authors: Veinguer Aurora Álvarez
Published: June 2013

This paper is based on ethnographic research conducted in Tatarstan between 1997 and 2000, during the process of ethno-national rebirth, when promotion of the Tatar language emerged as a key element of government policy. At this time, the linguistic landscape in Tatarstan was characterized by four distinct features which, far from being complementary, existed in a state of mutual tension: (1) a monolinguistic heritage, due to the historical dominance of Russian; (2) a claimed ‘bilingualism’ following the declaration of Tatarstan’s sovereignty; (3) the ethno-linguistic revival of Tatar, evident in some institutional contexts; and (4) the global monolinguistic hegemony of English in scientific and technological discourse, which made proficiency in English essential. Taking this complex background into account, this article analyzes the different attitudes to the Tatar language shown by pupils and teachers in Tatar and non-Tatar gymnásias (specialist secondary schools) in the capital city of Kazan.
Learning from each other: what social studies can learn from the controversy surrounding the teaching of evolution in science
Authors: Journell Wayne
Published: June 2013

This article addresses the need for researchers to move beyond discipline‐specific approaches to research and practice and offers an example of how interdisciplinary understandings can increase knowledge in respective disciplines. The specific focus of the article is the shared challenges of broaching controversy in science and social studies classrooms. Although there is much that social studies teachers can learn about the teaching of controversial public issues from the challenges science educators face in teaching evolutionary theory, and vice versa, the two literature bases have little overlap. Through this example of broaching curricular controversy in the classroom, the author argues that content instruction can be improved by increasing awareness of research and practice in other disciplines.
Electoral discourse and formative structural narratives of welfare divergence in multi-level systems: homelessness policy in UK elections 1970–2011
Authors: Chaney Paul
Published: June 2013

Over recent decades there has been an international shift towards multi-level governance. Against this backdrop, many comparative welfare studies take government policy outputs as the starting point for their analysis. However, the associated pluralization of electoral systems in unitary states means that welfare choices are no longer exclusively informed by single state-wide ballots. Accordingly, this study makes an original contribution by exploring the formative role of electoral discourse in shaping social policy divergence in (quasi-)federal states. It does this through an examination of party politicization and the issue-salience of homelessness in manifestos for UK state-wide and regional elections. The findings reveal how electoral discourse is a key driver of policy divergence. These territorially-specific structural narratives are used to propose a model of welfare divergence in multi-level systems, one that is cognizant of the formative role of electoral discourse in shaping the development of welfare regimes.
“Women without guardians” in Iran: gender, cultural assumptions, and social policy
Authors: Ostadalidehaghi Rezvan , Béland Daniel
Published: June 2013

This article explores the role of cultural assumptions in the formation of the only Iranian social programme designed exclusively for women, “Empowering Women without Guardians”. It examines these assumptions at different stages of the policy process: problem definition, policy formulation, and policy adoption. As shown, assumptions behind the adopted policy are not consistent with the ones underlying the original problem definition; women are considered mothers at the problem definition stage, but at the policy adoption stage they are understood as workers. The relative power of these assumptions helps explain both continuity and change in Iranian social policy towards women.