bluuebunny/crossref_metadata_2025 huggingface dataset:
Bidding strategy analysis of virtual power plant considering demand response and uncertainty of renewable energy
Authors: Zhang Gao , Jiang Chuanwen , Wang Xu , Li Bosong , Zhu Huagang
Published: June 2017

Due to the gradual exhaustion of petroleum‐based energy resources and severe concern for environmental protection, renewable energy (RE) resources and demand response (DR) techniques have been wide deployed in power network. However, the insufficient management as well as technology bottleneck becomes the major obstacle in their further development. Based on the uniform clearing of electricity market, a centralised dispatch model of virtual power plant (VPP) is introduced to improve the competitiveness of distributed energy resources in electricity market. To neutralise the side effect of RE penetration, a bidding strategy optimisation model considering DR and the uncertainty of RE for VPP is proposed and numerical analysis is conducted to prove its applicability. In addition, scenario analysis method is applied to deal with the influence of elastic demand and potential risk, which are associated with utility users’ consumption patterns and VPP's bidding preference, respectively. The application of distributed algorithm into multi‐players’ strategy optimisation problem accelerated the convergence of bidding procedure, which verifies the applicability and effectiveness of the proposed models. Furthermore, numerical case studies demonstrate the distinctive superiority of VPP in the integration and management of RE and DR resources, which in turn contribute to its advantage position in electricity market.
Mode identification of low‐frequency oscillations in power systems based on fourth‐order mixed mean cumulant and improved TLS‐ESPRIT algorithm
Authors: Jin Tao , Liu Siyi , Flesch Rodolfo C.C.
Published: June 2017

Wide area monitoring systems (WAMS) provide effective support for online identification of low‐frequency oscillations in power systems. The WAMS signal is sensitive to the surrounding environment, and it contains Gaussian white noise. The Gaussian white noise will produce Gaussian coloured noise through the filter, which will bring some errors to the mode identification. In order to solve the above problem, this study proposes a method to identify the low‐frequency oscillation modes of a single‐channel measurement of the power system based on the combination of the fourth‐order mixed mean cumulant and the improved TLS‐ESPRIT (total least square‐estimation parameter space rotation invariant technique). The actual signal is replaced by the processed signal using the fourth‐order mixed mean cumulant mathematical statistical method, thereby the Gaussian coloured noise is suppressed effectively; then, TLS‐ESPRIT algorithm is used to identify the signal, which is used to identify the low‐frequency oscillation of each mode. A novel relative change rate of singular value was also introduced in order to avoid the artificially threshold‐setting error. The simulation results show that the proposed method has better anti‐noise performance and higher accuracy of fitting than other methods reported in literature, besides being easy to be implemented and suitable for performing on‐line identification.
Utilisation of ultra‐capacitor in load frequency control under restructured STPP‐thermal power systems using WOA optimised PIDN‐FOPD controller
Authors: Saha Arindita , Saikia Lalit Chandra
Published: June 2017

This study addresses the impact of ultra‐capacitor (UC) on load frequency control of a restructured two‐area multi‐source system, incorporating conventional thermal and solar thermal power plant (STPP). The thermal system consists of single reheat turbine, appropriate generation rate constraint and governor dead band. Two generating companies and distribution companies are considered in each area. Maiden attempt has been made to use a cascade combination of integer‐order (IO) proportional–integral–derivative with filter and fractional‐order proportional–derivative (PIDN‐FOPD) controller. Performance comparison of some commonly used IO controllers with proposed PIDN‐FOPD controller reveals superiority of the latter in terms of peak deviations and settling time in policy schemes like poolco, bilateral and contract violation. A more recent optimisation technique called Whale optimisation algorithm (WOA) is successfully used for simultaneous optimisation of above controllers. Effect of UC using PIDN‐FOPD has been studied for above policy schemes and analysis explores that use of UC improves the system dynamics. Sensitivity analysis reveals that WOA optimised PIDN‐FOPD gains and system parameters are robust. It is also proved that PIDN‐FOPD parameters obtained at nominal distribution companies participation matrix (DPM) are fit enough and parameters need not be optimised for change in DPMs.
Coordinated state‐estimation method for air‐conditioning loads to provide primary frequency regulation service
Authors: Li Zihao , Wu Wenchuan , Zhang Boming
Published: June 2017

The penetration of large‐scale renewable generation leads to a shortage of primary frequency regulation resources as well as increasing regulation demand. By exploiting the thermal capacity of buildings, the authors achieve linear power–frequency characteristics comparable to turbine droop control via clustering a number of air‐conditioning units (ACs) to participate in primary frequency regulation without affecting indoor comfort. Due to the bandwidth limitations and latency in communication, the real‐time centralised control method face great challenges. This study proposes a two‐level coordinated state‐estimation method to reduce the coordination burden, in which a central coordinator and local controller for each AC are involved. The central coordinator periodically gathers the working state of every AC and estimated thermal parameters individually, then broadcasts this identified model parameters – the coordination information – to each local controller. Resorting to a state‐estimation method considering the coordinated information and local measurements, local controller determines whether to toggle the state of local AC to realise a fast frequency response. Simulation results show that the approach can effectively manage a large number of ACs with heterogeneous parameters to provide a primary frequency regulation service without inducing a rebound effect.
Research and applications of ground enhancing compounds in grounding systems
Authors: Androvitsaneas Vasilios P. , Gonos Ioannis F. , Stathopulos Ioannis A.
Published: June 2017

The operation and the behaviour of grounding systems are defined by some fundamental parameters: the rate of change in soil resistivity, the type and the size of grounding systems. The continuous improvement in designing these systems guarantees the maximum safety of people and electrical facilities. In the last decades, the usage of ground enhancing compounds (GECs) for soil alleviation and decreasing the ground resistance value becomes more and more popular in engineering field, particularly in electric power systems (transmission and distribution facilities) and in electric railway. This study provides an overview of the past and recent research, carried out on GECs, based on published scientific work during several decades. It includes computational and experimental work on these materials, both at steady‐state operation and under impulse conditions, from all over the world, and cites the most distinguish applications on grounding systems. It also refers to international standards that specify the requirements and tests for GECs producing low resistance of a ground termination system. This work aspires to be a useful guide to engineers and researchers who study, design and construct grounding systems using such materials for the optimisation of their operational performance.
Optimal placement of battery energy storage in distribution networks considering conservation voltage reduction and stochastic load composition
Authors: Zhang Yongxi , Ren Shuyun , Dong Zhao Yang , Xu Yan , Meng Ke , Zheng Yu
Published: June 2017

Deployment of battery energy storage (BES) in active distribution networks (ADNs) can provide many benefits in terms of energy management and voltage regulation. In this study, a stochastic optimal BES planning method considering conservation voltage reduction (CVR) is proposed for ADN with high‐level renewable energy resources. The proposed method aims to determine the optimal BES sizing and location to minimise the total investment and operation cost considering energy saving achieved by CVR, while satisfying system operational constraints in the presence of stochastic renewable power generation. The uncertainty of load composition is also modelled through scenario analysis. The proposed planning scheme is tested in a modified IEEE 15‐bus system and 43‐bus radial system, respectively. The numerical results validate that the combination of CVR and BES can achieve more energy savings.
Hybrid RVM–ANFIS algorithm for transformer fault diagnosis
Authors: Fan Jingmin , Wang Feng , Sun Qiuqin , Bin Feng , Liang Fangwei , Xiao Xuanyi
Published: June 2017

Dissolved gas analysis (DGA) is a popular method for diagnosing faults inside power transformers. However, some of the recorded data for the analysis are with ambiguous characteristic, leading to misdiagnosis of conventional methods. In this work, a hybrid method, which combines the relevance vector machine (RVM) and the adaptive neural fuzzy inference system (ANFIS) has been proposed to address this issue. Given the fuzziness between DGA records and fault type, and to minimise the number of rules that ANFIS needs to extract, the RVM algorithm performs binary separation firstly, and then ANFIS is utilised to achieve further fault diagnosis in this study. The experimental results demonstrate that the hybrid RVM–ANFIS algorithm can achieve an accuracy rate as high as 95%. Moreover, the proposed algorithm exceeds single ANFIS, support vector machine, and artificial neural network on distinguishing multiple faults and samples with ambiguous characteristic. The engineering application results also demonstrate the effectiveness and superiority of the proposed RVM–ANFIS.
Indentation instrumentée multi-échelles appliquée à l’étude des matériaux massifs métalliques
Authors: Kossman Stephania , Chicot Didier , Iost Alain
Published: June 2017

L’essai d’indentation instrumentée est une technique très utilisée car elle permet d’estimer les propriétés mécaniques des matériaux comme la dureté et le module de Young. Cette étude sur l’indentation multi-échelles (de 5 mN à 2 kN) a été réalisée sur des matériaux métalliques massifs (acier, acier inoxydable et aluminium) avec trois instruments : nano, micro et macro indenteurs, et différents types d’essais : classique, CSM et multicyclique. Nous avons constaté que, pour estimer les propriétés mécaniques, il est nécessaire de prendre en compte la correction du défaut de pointe et aussi de la complaisance du bâti quelle que soit l’échelle de mesure, et donc quelle que soit la conception de l’instrument pour la mesure du déplacement. Dans ces conditions, en considérant ces corrections, le module de Young reste quasi constant dans tout le domaine de force étudié (<12 %), et est donc à ce titre une propriété intrinsèque. Par contre, la dureté décroit lorsque la charge augmente, ce qui est classiquement attribué à l’effet de taille en indentation, mais qui peut aussi être imputé au mode de déformation autour de l’empreinte, au bourrelet prédominant (pile-up) pour les échantillons en acier et aluminium, et à la déflection des faces (sink-in) pour l’acier inoxydable.
Toxocariasis in Children: An Update on Clinical Manifestations, Diagnosis, and Treatment
Authors: Ramadan Manar , El-Sayed Nagwa
Published: June 2017

Toxocariasis, a parasitic infection, carries a major health risk in children, especially in the developing countries. Children are the most infected group because of their undeveloped immune system, their higher exposure to infection, and the frequency of reinfections depending on the factors related to their hygienic and behavioral habits. Many human infections are asymptomatic, with only eosinophilia and positive serology. However, several complications were associated with this neglected disease. These complications depend on the organs invaded by migrating Toxocara larvae, the degree of the larvae burden, and the strength of the host immune response. This review aims at giving an update on clinical manifestations, diagnosis, and treatment of toxocariasis in children. The pediatricians should merge this information into their clinical diagnosis to defeat this neglected disease by establishing the correct diagnosis and treatment.
Association Between Years of Experience and Ankle Joint Disorder in Male Student Basketball Players Based on Ultrasonography
Authors: Fukushima Yaeko
Published: June 2017

Purpose The goal of the study was to survey ankle joint disorder in male senior high school and college student basketball players based on the results of an ultrasonographic medical check-up of the ankle joint.

Materials and Methods The subjects were 17 senior high school student and 19 college student basketball players. Ultrasonography, evaluation of ATFL injury, and examination of the talocrural joint region were performed. The subjects were grouped based on the presence or absence of old ATFL injury, and subjects with ATFL injury were classified by the injured region: fibular insertion site, parenchyma, and talar insertion site. The talocrural joint region was evaluated based on the areas of the lateral margin, central region, and medial margin, and sites with an irregular bone contour and osteophyte were counted individually. The questionnaire asked about the patients’ history of ankle injuries.

Results A questionnaire survey revealed that 70–79% of all subjects had experienced a sprain at least once and 21–29% had frequently sprained the left or right foot 10 or more times in the past. On ultrasonography, there was no significant difference in ligament injury or injured site between the senior high school and college students, but the number of osteochondral findings in the talocrural joint region was significantly higher in the college students. In addition, the number of injured sites significantly increased in those with 10 or more years of playing experience.

Conclusion These results suggest that disorder of the talocrural joint region progresses with an increase in years of experience in student basketball players who do not take specific preventive measures against this injury.
Pflanzenschätze für die Haut
Authors: Huber Ellen
Published: June 2017

Heilpflanzen mit antibakteriellen und entzündungshemmenden Eigenschaften haben großes Potenzial für den Einsatz in der Wundheilung und Hautregeneration. Die Erfahrung zeigt, dass pflanzliche Zubereitungen seltener zu Resistenzbildung führen als klassische Antibiotika. Viele Pflanzen sind jedoch in Vergessenheit geraten. Darunter die hier vorgestellten: Schmalblättriges Weidenröschen, Kleine Braunelle und Vogelknöterich.
Slice imaging of the UV photodissociation of CH2BrCl from the maximum of the first absorption band
Authors: Chicharro D. V. , Marggi Poullain S. , González-Vázquez J. , Bañares L.
Published: June 2017

The photodissociation dynamics of bromochloromethane (CH2BrCl) have been investigated at the maximum of the first absorption band, at the excitation wavelengths 203 and 210 nm, using the slice imaging technique in combination with a probe detection of bromine-atom fragments, Br(2P3/2) and Br*(2P1/2), via (2 + 1) resonance enhanced multiphoton ionization. Translational energy distributions and angular distributions reported for both Br(2P3/2) and Br*(2P1/2) fragments show two contributions for the Br(2P3/2) channel and a single contribution for the Br*(2P1/2) channel. High level ab initio calculations have been performed in order to elucidate the dissociation mechanisms taking place. The computed absorption spectrum and potential energy curves indicate the main contribution of the populated 4A″, 5A′, and 6A′ excited states leading to a C–Br cleavage. Consistently with the results, the single contribution for the Br*(2P1/2) channel has been attributed to direct dissociation through the 6A′ state as well as an indirect dissociation of the 5A′ state requiring a 5A′ → 4A′ reverse non-adiabatic crossing. Similarly, a faster contribution for the Br(2P3/2) channel characterized by a similar energy partitioning and anisotropy than those for the Br*(2P1/2) channel is assigned to a direct dissociation through the 5A′ state, while the slower component appears to be due to the direct dissociation on the 4A″ state.
Hard-hard coupling assisted anomalous magnetoresistance effect in amine-ended single-molecule magnetic junction
Authors: Tang Y.-H. , Lin C.-J. , Chiang K.-R.
Published: June 2017

We proposed a single-molecule magnetic junction (SMMJ), composed of a dissociated amine-ended benzene sandwiched between two Co tip-like nanowires. To better simulate the break junction technique for real SMMJs, the first-principles calculation associated with the hard-hard coupling between a amine-linker and Co tip-atom is carried out for SMMJs with mechanical strain and under an external bias. We predict an anomalous magnetoresistance (MR) effect, including strain-induced sign reversal and bias-induced enhancement of the MR value, which is in sharp contrast to the normal MR effect in conventional magnetic tunnel junctions. The underlying mechanism is the interplay between four spin-polarized currents in parallel and anti-parallel magnetic configurations, originated from the pronounced spin-up transmission feature in the parallel case and spiky transmission peaks in other three spin-polarized channels. These intriguing findings may open a new arena in which magnetotransport and hard-hard coupling are closely coupled in SMMJs and can be dually controlled either via mechanical strain or by an external bias.
Perpendicular magnetic anisotropy of TiN buffered Co2FeAl/MgO bilayers
Authors: Niesen Alessia , Ludwig Jana , Glas Manuel , Silber Robin , Schmalhorst Jan-Michael , Arenholz Elke , Reiss Günter
Published: June 2017

We investigated crystallographic and magnetic properties of TiN buffered Co2FeAl thin films. Room temperature deposition of the Heusler compound led to high crystalline ordering. The layer thickness and post annealing temperature dependence of the coercivity, squareness ratio, and the anisotropy constant of the thin Co2FeAl films were measured. High perpendicular magnetic anisotropy was observed for the 0.9 nm thin Co2FeAl film. A squareness ratio of one was reached at 325 °C post annealing temperature, which is lower compared to previous studies. It remained constant for temperatures up to 500 °C. Surface sensitive x-ray absorption and x-ray magneto circular dichroism measurements were carried out, in order to investigate the element specific magnetic moments. A magnetic moment of 5.4 ± 0.4 μB/f.u. for the 1 nm thin Co2FeAl was determined, which is in good agreement with the previously reported values for Cr or MgO buffered Co2FeAl.
Microwave attenuators for use with quantum devices below 100 mK
Authors: Yeh Jen-Hao , LeFebvre Jay , Premaratne Shavindra , Wellstood F. C. , Palmer B. S.
Published: June 2017

To reduce the level of thermally generated electrical noise transmitted to superconducting quantum devices operating at 20 mK, we have developed thin-film microwave power attenuators operating from 1 to 10 GHz. The 20 and 30 dB attenuators are built on a quartz substrate and use 75 nm thick films of nichrome for dissipative components and 1 μm thick silver films as hot electron heat sinks. The noise temperature of the attenuators was quantified by connecting the output to a 3D cavity containing a transmon qubit and extracting the dephasing rate of the qubit as a function of temperature and dissipated power Pd in the attenuator. The minimum noise temperature Tn of the output from the 20 dB attenuator was Tn≤53 mK for no additional applied power and Tn≈120 mK when dissipating 30 nW. In the limit of large dissipated power (Pd>1 nW), we find Tn∝Pd1/5.4, consistent with detailed thermal modeling of heat flow in the attenuators.
Hamilton-Jacobi approach to potential functions in information geometry
Authors: Ciaglia Florio M. , Di Cosmo Fabio , Felice Domenico , Mancini Stefano , Marmo Giuseppe , Pérez-Pardo Juan M.
Published: June 2017

The search for a potential function S allowing us to reconstruct a given metric tensor g and a given symmetric covariant tensor T on a manifold M is formulated as the Hamilton-Jacobi problem associated with a canonically defined Lagrangian on TM. The connection between this problem, the geometric structure of the space of pure states of quantum mechanics, and the theory of contrast functions of classical information geometry are outlined.
A compact linear accelerator based on a scalable microelectromechanical-system RF-structure
Authors: Persaud A. , Ji Q. , Feinberg E. , Seidl P. A. , Waldron W. L. , Schenkel T. , Lal A. , Vinayakumar K. B. , Ardanuc S. , Hammer D. A.
Published: June 2017

A new approach for a compact radio-frequency (RF) accelerator structure is presented. The new accelerator architecture is based on the Multiple Electrostatic Quadrupole Array Linear Accelerator (MEQALAC) structure that was first developed in the 1980s. The MEQALAC utilized RF resonators producing the accelerating fields and providing for higher beam currents through parallel beamlets focused using arrays of electrostatic quadrupoles (ESQs). While the early work obtained ESQs with lateral dimensions on the order of a few centimeters, using a printed circuit board (PCB), we reduce the characteristic dimension to the millimeter regime, while massively scaling up the potential number of parallel beamlets. Using Microelectromechanical systems scalable fabrication approaches, we are working on further reducing the characteristic dimension to the sub-millimeter regime. The technology is based on RF-acceleration components and ESQs implemented in the PCB or silicon wafers where each beamlet passes through beam apertures in the wafer. The complete accelerator is then assembled by stacking these wafers. This approach has the potential for fast and inexpensive batch fabrication of the components and flexibility in system design for application specific beam energies and currents. For prototyping the accelerator architecture, the components have been fabricated using the PCB. In this paper, we present proof of concept results of the principal components using the PCB: RF acceleration and ESQ focusing. Ongoing developments on implementing components in silicon and scaling of the accelerator technology to high currents and beam energies are discussed.
Size effect on dynamics and glass transition in metallic liquids and glasses
Authors: Li Y. Z. , Sun Y. T. , Lu Z. , Li M. Z. , Bai H. Y. , Wang W. H.
Published: June 2017

The relaxation dynamics and glass transition in finite-sized metallic liquid droplets were investigated via molecular dynamic simulations in model monoatomic Ta and binary Cu50Zr50 metallic liquids. We find that the droplet size has a significant impact on liquid dynamics and glass transition. Glass transition temperature and structural relaxation time exhibit strong size dependence and decrease drastically as the droplet is smaller than a certain size. It is revealed that this results from a liquid-like surface layer (∼1 nm thick) of droplets, in which the dynamics is much faster than the interior of droplets. A proposed scaling relationship can well describe the size dependent behavior of the glass transition temperature in metallic liquid droplets. These findings provide insight into the dynamics of metallic liquid droplets and plausible understanding of recent novel experimental observations. Apart from temperature and pressure, size may be another important parameter for potentially tuning the properties of metallic liquids and glasses in nanometer scale.
Triple nuclear reactions (d, n) in laser-generated plasma from deuterated targets
Authors: Torrisi Lorenzo , Cutroneo Mariapompea
Published: June 2017

Measurements performed at Prague Asterix Laser System laboratory have permitted to study nuclear reactions in plasma produced by high intensity laser pulses (1016 W/cm2) accelerating high energetic ions. In particular, the laser irradiation of deuterated polyethylene (CD2) primary target, as thin foils, has produced the ion acceleration of C and D ions, and the presence of a thick LiD secondary target has produced nuclear reaction events due to the deuteron-deuteron, deuterons-lithium, and deuteron-carbon interactions. Fast and slow neutrons have been obtained mainly from the nuclear reactions 7Li(d, n)8Be, 2H(d, n)3He, and 12C(d, n)13N. Plasma monitoring and measurements of kinetic energies of produced particles in different directions were obtained using many detectors. The analyses were based on a semiconductor time-of-flight technique, an electric and magnetic ion deflection in a Thomson spectrometer, and ion track detectors. The maximum yields of neutrons produced in the used experimental conditions were evaluated to be about 4 × 108 and 3 × 108 neutrons/laser shot at energies of 14 MeV and 2.4 MeV, from the D-Li and D-D reactions, respectively, while the production of low energy neutrons from the third D-C reaction was negligible.
A broadband LED source in visible to short-wave-infrared wavelengths for spectral tumor diagnostics
Authors: Hayashi Daiyu , van Dongen Anne Marie , Boerekamp Jack , Spoor Sandra , Lucassen Gerald , Schleipen Jean
Published: June 2017

Various tumor types exhibit the spectral fingerprints in the absorption and reflection spectra in visible and especially in near- to short-wave-infrared wavelength ranges. For the purpose of spectral tumor diagnostics by means of diffuse reflectance spectroscopy, we developed a broadband light emitting diode (LED) source consisting of a blue LED for optical excitation, Lu3Al5O12:Ce3+,Cr3+ luminescent garnet for visible to near infrared emissions, and Bismuth doped GeO2 luminescent glass for near-infrared to short-wave infrared emissions. It emits broad-band light emissions continuously in 470–1600 nm with a spectral gap at 900–1000 nm. In comparison to the currently available broadband light sources like halogen lamps, high-pressure discharge lamps and super continuum lasers, the light sources of this paper has significant advantages for spectral tissue diagnostics in high-spectral stability, improved light coupling to optical fibers, potential in low light source cost and enabling battery-drive.
Direct and indirect determination of electrocaloric effect in Na0.5Bi0.5TiO3
Authors: Birks E. , Dunce M. , Peräntie J. , Hagberg J. , Sternberg A.
Published: June 2017

Direct and indirect studies of the electrocaloric effect were carried out in poled and depoled Na0.5Bi0.5TiO3. For this purpose, polarization and electrocaloric effect temperature change measurements were made at different electric field pulses as a function of temperature. The applicability of the widely used indirect electrocaloric effect determination method, using the Maxwell relation, was critically analyzed with respect to the reliable direct measurements. Quantitative differences were observed between the results obtained by both approaches in the case of the poled Na0.5Bi0.5TiO3 sample. These differences can be explained by the temperature-dependent concentration of domains oriented in the direction of the applied electric field. Whereas in depoled Na0.5Bi0.5TiO3, which is characterized by the electric field dependence of polar nanoregions embedded in a nonpolar matrix, the Maxwell relation is not applicable at all, as it is indicated by the obtained results. Possible mechanisms which could be responsible for the electrocaloric effect in the relaxor state were considered. The results of this study are used to evaluate the numerous results obtained and published by other authors, using the Maxwell relation to indirectly determine the electrocaloric effect. The reason for the negative values of the electrocaloric effect, obtained in such a way and widely discussed in the literature in the case of Na0.5Bi0.5TiO3, has been explained in this study.
Capsule implosions for continuum x-ray backlighting of opacity samples at the National Ignition Facility
Authors: Opachich Y. P. , Heeter R. F. , Barrios M. A. , Garcia E. M. , Craxton R. S. , King J. A. , Liedahl D. A. , McKenty P. W. , Schneider M. B. , May M. J. , Zhang R. , Ross P. W. , Kline J. L. , Moore A. S. , Weaver J. L. , Flippo K. A. , Perry T. S.
Published: June 2017

Direct drive implosions of plastic capsules have been performed at the National Ignition Facility to provide a broad-spectrum (500–2000 eV) X-ray continuum source for X-ray transmission spectroscopy. The source was developed for the high-temperature plasma opacity experimental platform. Initial experiments using 2.0 mm diameter polyalpha-methyl styrene capsules with ∼20 μm thickness have been performed. X-ray yields of up to ∼1 kJ/sr have been measured using the Dante multichannel diode array. The backlighter source size was measured to be ∼100 μm FWHM, with ∼350 ps pulse duration during the peak emission stage. Results are used to simulate transmission spectra for a hypothetical iron opacity sample at 150 eV, enabling the derivation of photometrics requirements for future opacity experiments.
Shrinking of core neoclassical tearing mode magnetic islands due to edge localized modes and the role of ion-scale turbulence in island recovery in DIII-D
Authors: Bardóczi L. , Rhodes T. L. , Carter T. A. , La Haye R. J. , Bañón Navarro A. , McKee G. R.
Published: June 2017

Experimental signature of long-wavelength turbulence accelerating the recovery of Neoclassical Tearing Mode (NTM) magnetic islands after they have been transiently reduced in size due to interaction with Edge Localized Modes (ELMs) is reported for the first time. This work shows that perturbations associated with ELMs result in peaking of the electron temperature (Te) in the O-point region of saturated core m/n = 2/1 islands (m/n being the poloidal/toroidal mode numbers). In synchronization with this Te peak, the island width shrinks by as much as 30% suggesting a key role of the Te peak in NTM stability due to modified pressure gradient (∇p) and perturbed bootstrap current (δjBS) at the O-point. Next, this Te peak relaxes via anomalous transport (i.e., the diffusivity is 2 orders of magnitude larger than the neoclassical value) and the island recovers. Long-wavelength turbulent density fluctuations (ñ) are reduced at the O-point of flat islands but these fluctuations are increased when Te is peaked which offers an explanation for the observed anomalous transport that is responsible for the relaxation of the Te peak. Linear gyrokinetic simulations indicate that ñ inside the peaked island is dominantly driven by the Ion Temperature Gradient instability. These measurements suggest that ñ accelerates NTM recovery after an ELM crash via accelerating the relaxation of ∇p at the O-point. These observations are qualitatively replicated by coupled predator-prey equations and modified Rutherford equation. In this simple model, turbulence accelerates NTM recovery via relaxing ∇p and therefore restoring δjBS at the O-point. The key physics of the relationship between the Te peak and NTM stability has potentially far-reaching consequences, such as NTM control via pellet injection in high-β tokamak plasmas.
Over the barrier electron transfer from a micron sized charged dust particle to an ion in gas discharge plasmas
Authors: Bastykova N. Kh. , Kodanova S. K. , Ramazanov T. S. , Moldabekov Zh. A.
Published: June 2017

A simple semiclassical model for the calculation of the electron transfer cross section from the dust particle to the ion is presented. The key ingredient of the model is the transition rate of the electron from the charged dust particle to the ion as a function of the distance between them. Particularly, over the barrier electron transfer from the micron sized spherical dust particle to the surrounding plasma ion is considered. The cross section of this process for the strong dust particle-ion coupling regime, which corresponds to the case of the room temperature gas discharge plasma, is presented. The obtained data were analyzed by comparing them with the ion absorption cross section on the surface of the dust particle. It is found that in the case of micron sized dust particles, more than 15% of ion recombinations with a charged dust particle's electron is due to over the barrier electron transfer. It has been shown that in the considered range of parameters, the cross section of over the barrier electron transfer from the negatively charged dust particle to the ion can be presented in a simple analytical form despite strong nonlinearity of the ion-dust scattering problem.
Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties
Authors: Ramaneti R. , Sankaran K. J. , Korneychuk S. , Yeh C. J. , Degutis G. , Leou K. C. , Verbeeck J. , Van Bael M. K. , Lin I. N. , Haenen K.
Published: June 2017

A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of the DGH nanorods, which contain sp2-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices.
Static and dynamic magnetic properties of FeMn/Pt multilayers
Authors: Luo Ziyan , Yang Yumeng , Xu Yanjun , Zhang Mengzhen , Xu Baoxi , Chen Jingsheng , Wu Yihong
Published: June 2017

Recently, we have demonstrated the presence of spin-orbit torque in FeMn/Pt multilayers which, in combination with the anisotropy field, is able to rotate its magnetization consecutively from 0° to 360° without any external field. Here, we report on an investigation of the static and dynamic magnetic properties of FeMn/Pt multilayers using the combined techniques of magnetometry, ferromagnetic resonance, inverse spin Hall effect, and spin Hall magnetoresistance measurements. The FeMn/Pt multilayer was found to exhibit ferromagnetic properties, and its temperature dependence of saturation magnetization can be fitted well using a phenomenological model by including a finite distribution in Curie temperature due to subtle thickness variations across the multilayer samples. The non-uniformity in static magnetic properties is also manifested in the ferromagnetic resonance spectra, which typically exhibit a broad resonance peak. A damping parameter of around 0.106 is derived from the frequency dependence of ferromagnetic resonance linewidth, which is comparable to the reported values for other types of Pt-based multilayers. Clear inverse spin Hall signals and spin Hall magnetoresistance have been observed in all samples below the Curie temperature, which corroborate the strong spin-orbit torque effect observed previously.
Impact of bias stability for crystalline InZnO thin-film transistors
Authors: Kim Hojoong , Choi Daehwan , Park Solah , Park Kyung , Park Hyun-Woo , Chung Kwun-Bum , Kwon Jang-Yeon
Published: June 2017

Crystallized InZnO thin-film transistors (IZO TFTs) are investigated to identify a potential for the maintenance of high electrical performances with a consistent stability. The transition from an amorphous to a crystallization structure appeared at an annealing temperature around 800 °C, and it was observed using transmission electron microscopy and time-of-flight secondary ion mass spectrometry analysis. The field-effect mobility of the crystallized IZO TFTs was boosted up to 53.58 cm2/V s compared with the 11.79 cm2/V s of the amorphous devices, and the bias stability under the negative stress was greatly enhanced even under illumination. The defect states related to the oxygen vacancy near the conduction band edge decreased after the crystallization, which is a form of electrical structure evidence for the reliability impact regarding the crystallized IZO TFTs.
Extensible 3D architecture for superconducting quantum computing
Authors: Liu Qiang , Li Mengmeng , Dai Kunzhe , Zhang Ke , Xue Guangming , Tan Xinsheng , Yu Haifeng , Yu Yang
Published: June 2017

Using a multi-layered printed circuit board, we propose a 3D architecture suitable for packaging superconducting chips, especially chips that contain two-dimensional qubit arrays. In our proposed architecture, the center strips of the buried coplanar waveguides protrude from the surface of a dielectric layer as contacts. Since the contacts extend beyond the surface of the dielectric layer, chips can simply be flip-chip packaged with on-chip receptacles clinging to the contacts. Using this scheme, we packaged a multi-qubit chip and performed single-qubit and two-qubit quantum gate operations. The results indicate that this 3D architecture provides a promising scheme for scalable quantum computing.
Dimensional analysis and prediction of dielectrophoretic crossover frequency of spherical particles
Authors: Yeh Che-Kai , Juang Jia-Yang
Published: June 2017

The manipulation of biological cells and micrometer-scale particles using dielectrophoresis (DEP) is an indispensable technique for lab-on-a-chip systems for many biological and colloidal science applications. However, existing models, including the dipole model and numerical simulations based on Maxwell stress tensor (MST), cannot achieve high accuracy and high computation efficiency at the same time. The dipole model is widely used and provides adequate predictions on the crossover frequency of submicron particles, but cannot predict the crossover frequency for larger particles accurately; on the other hand, the MST method offers high accuracy for a wide variety of particle sizes and shapes, but is time-consuming and may lack predictive understanding of the interplay between key parameters. Here we present a mathematical model, using dimensional analysis and the Buckingham pi theorem, that permits high accuracy and efficiency in predicting the crossover frequency of spherical particles. The curve fitting and calculation are performed using commercial packages OriginLab and MATLAB, respectively. In addition, through this model we also can predict the conditions in which no crossover frequency exists. Also, we propose a pair of dimensionless parameters, forming a functional relation, that provide physical insights into the dependency of the crossover frequency on five key parameters. The model is verified under several scenarios using comprehensive MST simulations by COMSOL Multiphysics software (COMSOL, Inc.) and some published experimental data.
Expression patterns of two carbonic anhydrase genes, Na+/K+-ATPase and V-type H+-ATPase, in the freshwater crayfish, Cherax quadricarinatus, exposed to low pH and high pH
Authors: Ali Muhammad Yousuf , Pavasovic Ana , Mather Peter B. , Prentis Peter J.
Published: June 2017

Carbonic anhydrase (CA), Na+/K+-ATPase (NKA) and Vacuolar-type H+-ATPase (HAT) play vital roles in osmoregulation and pH balance in decapod crustaceans. As variable pH levels have a significant impact on the physiology of crustaceans, it is crucial to understand the mechanisms by which an animal maintains its internal pH. We examined expression patterns of cytoplasmic (CAc) and membrane-associated form (CAg) of CA, NKA α subunit and HAT subunit a in gills of freshwater crayfish, Cherax quadricarinatus, at three pH levels – 6.2, 7.2 (control) and 8.2 – over 24 h. Expression levels of CAc were significantly increased at low pH and decreased at high pH conditions 24 h after transfer. Expression increased at low pH after 12 h, and reached its maximum level by 24 h. CAg showed a significant increase in expression at 6 h after transfer at low pH. Expression of NKA significantly increased at 6 h after transfer to pH 6.2 and remained elevated for up to 24 h. Expression for HAT and NKA showed similar patterns, where expression significantly increased 6 h after transfer to low pH and remained significantly elevated throughout the experiment. Overall, CAc, CAg, NKA and HAT gene expression is induced at low pH conditions in freshwater crayfish.
Water is an active matrix of life for cell and molecular biology
Authors: Ball Philip
Published: June 2017

Szent-Győrgi called water the “matrix of life” and claimed that there was no life without it. This statement is true, as far as we know, on our planet, but it is not clear whether it must hold throughout the cosmos. To evaluate that question requires a close consideration of the many varied and subtle roles that water plays in living cells—a consideration that must be free of both an assumed essentialism that gives water an almost mystical life-giving agency and a traditional tendency to see it as a merely passive solvent. Water is a participant in the “life of the cell,” and here I describe some of the features of that active agency. Water's value for molecular biology comes from both the structural and dynamic characteristics of its status as a complex, structured liquid as well as its nature as a polar, protic, and amphoteric reagent. Any discussion of water as life’s matrix must, however, begin with an acknowledgment that our understanding of it as both a liquid and a solvent is still incomplete.
The Internet in translation education
Authors: Jiménez-Crespo Miguel A.
Published: June 2017

Within the context of the global digital revolution, translation in professional settings cannot be understood without the Internet, as a communicative, documentary, and productivity tool (Cronin 2013; Jimenez-Crespo 2013). Similarly, translation training has been revolutionized by the wide range of possibilities afforded by the Internet. This paper reviews the impact of the Internet on translation research within the framework of translation competence models (PACTE 2005; Göpferich 2009), as well as socio-constructivist approaches to translation education (Kiraly 2012; 2000). Its impact has been felt in two areas: (1) how translation is taught and (2) how the world of translation has been changed by the Internet. Related to the first area is the rapid increase in the number of online and hybrid programs offered and in the use of online teaching platforms in classroom-based contexts. Related to the second area, a wide range of new opportunities has arisen, such as: (1) those related to the Internet as a communicative platform, (2) those related to the use of the Internet during translation tasks, both in terms of cloud-based translation memory and human-aided machine translation, as well as the use of the Internet for ‘external support’ (Alves and Liparini 2009) to solve translation problems, and (3) the emergence of new translation modalities such as web localization, new textual genres, such as social networking sites or tweets, as well as new translation practices, such as online crowdsourcing and volunteer translation communities.
I know languages, therefore, I can translate?
Authors: Zlatnar Moe Marija , Mikolič Južnič Tamara , Žigon Tanja
Published: June 2017

There is a large presence of translators without formal education in the Slovene market, partly because until the 1990s there were no independent translation programs, but also because of the popular notion that anybody who speaks a foreign language well, or has a degree in it, can translate. In this paper we present a comparison of four B.A. programs at the University of Ljubljana (in three foreign language departments and one department of translation) to shed light on what knowledge and competences are expected at the end of the B.A. studies, and to find out whether these departments actually train people to be translators. The paper also reports the results of a translation quality assessment of third-year students of those departments, who were given the task of translating a text into their L1. The students approached the task in different ways and produced very different results, which indicates that language competences alone are not enough for translation, and that specific additional instruction can give them a considerable advantage at the beginning of their careers.
L2 proficiency as predictor of aptitude for interpreting
Authors: Blasco Mayor Maria Jesus
Published: June 2017

This study reports findings from an experiment that was conducted to investigate language proficiency as an indicator of future interpreting performance. The initial assumption was that Spanish undergraduate translation and interpreting students had an insufficient command of L2 skills to start interpreter training. We hypothesized that an intensive teaching module on L2 phonology and listening comprehension would improve their academic performance in interpreting. Several tests were used to evaluate participant L2 listening comprehension (TOEFL), L2 reading comprehension (TOEFL), L2 grammar (TOEFL), and L1 verbal fluency (WAIS-III). Only those related to L2 are reported here. A consecutive interpreting test was given at the end of the first interpretation module. The students’ self-perception regarding L2 issues was assessed using two questionnaires and an interview. The results suggest that L2 listening comprehension training aided in consecutive interpreting performance. Language proficiency was also found to correlate with interpreting scores. A base level of L2 proficiency for interpreting training is suggested. We conclude that L2 listening comprehension proficiency has a significant effect on undergraduate students’ interpreting ability and is therefore a suitable predictor for interpreting aptitude. Consequently, L2 listening skills should be included in the interpreting program curriculum, preferably before interpretation classes start.
Does the verb raise to T in Spanish?
Authors: Camacho José , Sánchez Liliana
Published: June 2017

We test adverb-verb word orders in Peruvian Spanish against analyses of verb movement (Pollock 1989, Embick & Noyer 2001). While the preferred order is V-adv-O, the alternative Adv-V-O is also possible. We propose that the verb raises in overt syntax and morphological insertion targets either the higher or the lower position. In the latter case, morphological requirements force the more computationally costly option of T-to-V lowering. We analyze the ungrammaticality of neg-adv-V as a blocking of the selectional restriction requirements of neg (the extended verbal projection, including T) by the intervening adverb. This distribution is parallel to English do-insertion in negative contexts (I don’t frequently eat vs. * I not frequently eat), where neg selects for a -T category (cf. Williams 1994).
On weak definites and their contribution to event kinds
Authors: Espinal M.Teresa , Cyrino Sonia
Published: June 2017

In this paper we focus on the meaning of definite DPs that allow a weak reading. We review three different proposals for weak definites, and we present a new analysis with special reference to Romance languages. We submit that the eventual weak reading of a definite DP and its contribution to a ‘familiar’ kind of activity is exclusively dependent on whether certain stereotypical information encoded on the N present in the DP is activated at the time of utterance interpretation. These DPs do not refer to kinds and do not correspond to incorporated objects. Hence, their interpretation is not compositionally driven, but rather pragmatically inferred. We predict that the identification of weak definites takes place beyond grammar and is constrained by encyclopedic information.