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High Temperature Superconducting (HTS) dynamo flux pumps are a promising alternative to metal current leads for energization and the persistent current mode operation of high current DC superconducting magnet systems for applications in rotating machines, such as Magnetic Resonance Imaging (MRI) or fusion systems. The viability of the flux pump concept has been widely proven by laboratory experiments and research is now in progress for the design and optimization of flux pump devices for practical applications. It has been widely established that the dependence of the critical current density (Jc) on the temperature (T), the magnetic field magnitude (B), and the orientation (θ), has a substantial impact on the overall DC voltage obtained at the terminals, as well as on the current limit and the loss of the flux pump. Since HTS tapes produced by different manufacturers, they show different dependencies of Jc with the amplitude and the orientation of the magnetic field. They also give rise to different outputs when employed in flux pumps. In this paper, we evaluate and compare the performance of several commercial HTS tapes used for flux pumping purposes through numerical simulation. We also investigate the dependence of the flux pump 's performance on the operating temperatures. A 2D finite element numerical model is first developed and validated against experimental data at 77 K. Afterward, the same HTS dynamo apparatus used for validation is exploited for the comparison. The Jc(B,θ,T) and n (B,θ,T) relations, which characterize each different tape in the model, are reconstructed via artificial intelligence techniques based on the open-access database of the Robinson Research Institute. It is shown in the paper that certain tapes are more suitable than others for flux pump applications and that the best overall operating temperature is in the vicinity of 77 K. [ABSTRACT FROM AUTHOR]

SMES technology based on MgB 2 superconductor and cryogenic-free cooling can offer a viable solution to power-intensive storage in the short term. One of the main obstacles to the development of dry-cooled SMES systems is the heat load removal due to the AC loss of the superconductor during fast charging and discharging cycles at high power. Accurate knowledge of the amount and distribution of AC loss in the coil is of paramount importance for the sizing and the design of the cooling system and for assessing the possible operational limits of the technology. In this manuscript, the AC loss of a 500 kJ/200 kW multifilamentary MgB 2 SMES during charge–discharge cycling at full power is numerically investigated. The methodology and assumptions of the calculation are briefly resumed, and numerical results are reported and discussed in detail. In particular, the time profile and the distribution of the dissipated power all over the coil are reported. An average dissipation of 85.5 mW/m is found all over the coil during one charge–discharge cycle at full power, with a peak of 150.1 mW/m in the turns lying at the ends of the coil. [ABSTRACT FROM AUTHOR]

High temperature superconductivity is emerging as a solution for lightweight, cost-effective and high-power wind generators. Current injection and maintainment/sustainment in the field winding are obtained by metal current leads which, due to persistent heat conduction and joule loss, are responsible for a large part of the total cryogenic heat load. Slip rings, which further reduce the overall performance and reliability of the system, are also required. In this paper we assess the viability of the HTS dynamo and the rectifier flux pumps for energizing the field coils of the EcoSwing 3.6 MW HTS wind generator. Both a "warm" solution, with the rectifier at room temperature, and a "cold" solution, in which the latter is integrated into the cryostat, are investigated with regard to the rectifier flux pump. A comparison with the actual, state-of-the-art, system of the EcoSwing machine is carried out in terms of the total required cooling power and the ability to charge the HTS field winding up to the rated current. It is found that the dynamo flux pump, beside avoiding the need of slip rings, allows the reduction in the required cooling by about 74% with respect to the conventional current-leads-based solution. [ABSTRACT FROM AUTHOR]

The volume integral equation method based on the current vector potential approximated by means edge element basis function is a well-established approach for 3-D eddy currents computation. The application of the method is straightforward when simply connected geometries and no connection with external circuits are involved. In this case, in fact, the solving system is easily obtained based on tree–cotree decomposition of the primal graph. However, when multiply connected geometries or external generators are considered, “additional” degrees of freedom, not related to interior cotree edges of the primal graph, need to be identified and involved to assure the consistency of the numerical solution. In this article, the link between the volume integral equation method and the circuit is investigated in detail, and the circuit view is used as a guide for systematically finding the additional degrees of freedom arising in case of multiply connected geometries and/or external circuits. In particular, the dual graph is introduced as the support of the circuit and it is shown that this is the natural frame for taking the topology into account. For multiply connected geometries, the additional degrees of freedom are related to loop currents crossing one only time (or an odd number of times) any cutting surface making the domain simply connected, and are found by applying a minimum path algorithm on the dual graph forming the circuit. In case of conducting domain connected to an external generator, an extended dual graph is introduced for finding the further additional degrees of freedom. This article also researches into the possibility to replace the usual current density of the elements, obtained via facet-element shape functions and exactly matching the current of the faces, with a uniform current density obtained by means of a minimum error procedure and approximately matching the current of the faces. The use of this uniform current density, besides improving the calculation time and the accuracy of the coupling coefficients, also allows the extension of the volume integral equation method to discretizations of the problem domain made of arbitrarily shaped polyhedral elements. [ABSTRACT FROM AUTHOR]

Background: Ayurveda is a traditional Indian system of medicine. The customized Ayurvedic approach consists of a combination of several diagnostic procedures and subsequent individualized therapeutic interventions. Evaluation of inter-rater reliability (IRR) of Ayurvedic diagnoses has rarely been performed. The aim of this study was to evaluate IRR of Ayurvedic diagnosis for patients with knee osteoarthritis. Methods: A diagnostic reliability study of 30 patients and 4 Ayurvedic experts was nested in a randomized controlled trial. Patients were diagnosed in a sequential order by all experts utilizing a semistructured patient history form. A nominal group technique as consensus procedure was performed to reach agreement on the items to be diagnosed. An IRR analysis using Fleiss' and Cohen's kappa statistics was performed to determine a chance-corrected measure of agreement among raters. Results: One hundred and twenty different ratings and 30 consensus ratings were performed and analyzed. While high percentages of agreement for main diagnostic entities and the final Ayurveda diagnosis (95% consensus agreement on main diagnosis) could be observed, this was not reflected in the corresponding kappa values, which largely yielded fair-to-poor inter-rater agreement kappas for central diagnostic aspects such as prakriti and agni (κ values between 0 and 0.4). Notably, agreement on disease-related entities was better than that on constitutional entities. Conclusions: This is the first diagnostic study embedded in a clinical trial on patients with knee osteoarthritis utilizing a multimodality whole systems approach. Results showed a contrast between the high agreement of the consented final diagnosis and disagreement on certain diagnostic details. Future diagnostic studies should have larger sample sizes and a methodology more tailored to the specificities of traditional whole systems of medicine. Equal emphasis will need to be placed on all core diagnostic components of Ayurveda, both constitutional and disease specific, using detailed structured history taking forms. [ABSTRACT FROM AUTHOR]

A three-year research project, called DRYSMES 4GRID, was recently funded by the Italian Minister of Economic Development, Italy. The project, which involves five Italian partners (companies, universities, and research institutes), is aimed to demonstrate the feasibility of cost-competitive SMES based on magnesium diboride (MgB2 ) with a cryogen-free cooling bymeans of the manufacturing and the testing of a demonstrator with an objective rating of 500 kJ/200 kW. This rating is deemed suitable for disclosing the critical technological aspects of all components in view of practical applications. A further goal of the project is the assessment of the technical and economic benefits that the SMES can bring to real-world electric grids. The general outline and technical objectives of the project are presented in this paper. Preliminary design assumptions and results concerning the MgB2 coil and the power condition system are also discussed. [ABSTRACT FROM AUTHOR]

MgB2 material operating at moderate field can conveniently be considered for short-term cost-effective implementation of superconducting magnetic energy storage (SMES). Due to the intrinsic performance of this material, moderate field operation and cryogen free cooling in the range 10–20 K need to be considered. For investigating the feasibility of MgB2 based SMES technology a 10 kW—2 s system is under development. A small MgB2 coil was developed and tested as the first step of this study. The cooling was obtained by means of a cryogen-free test facility based on a two-stages Gifford–McMahon regenerative heat exchanger. A power conditioning system (PCS) was also developed in order to connect the coil with the power grid. The PCS is based on power mosfet components and consists of two parallel dc/dc boost converters and an inverter connected to a common dc bus at 100 V. Continuous operation of the coil at a charge/discharge rate up to 24 kW can be achieved by means of the PCS. Details of the layout of the coil and the thermal connection with the cryocooler are discussed in this paper. Results of cooling test are reported. Possible SMES operation is also discussed. [ABSTRACT FROM PUBLISHER]

An innovative linear levitating system based on \MgB2 bulks produced by the reactive liquid infiltration method is designed and built. Details of the system are presented. The levitation performance is also evaluated by means of previous experimental data. The linear levitating system consists of four \MgB2 arc-shaped tiles lodged inside a double-shell Dewar sliding on a guide made of Nd-Fe-B permanent magnets. The magnets on the guide are properly arranged in a flux shaper configuration in order to produce maximum stiffness. Each \MgB2 bulk has a curvature radius of 165 mm (arc length of 200 mm), thickness of 10 mm, and width of 70 mm. The system is cooled by means of a solid nitrogen heat sink. Helium gas supply to a heat exchanger is used in order to cool down the \MgB2 slabs and the nitrogen at a temperature in the range of 20–30 K. When the flow of helium gas is interrupted, the temperature of the solid nitrogen remains below 39 K for half an hour. During this time interval, levitation measurements can be performed. Experimental verification of the cooling concept has been carried out successfully. [ABSTRACT FROM PUBLISHER]

Abstract: Modern electric power systems are becoming more and more complex in order to meet new needs. Nowadays a high power quality is mandatory and there is the need to integrate increasing amounts of on-site generation. All this translates in more sophisticated electric network with intrinsically high short circuit rate. This network is vulnerable in case of fault and special protection apparatus and procedures needs to be developed in order to avoid costly or even irreversible damage. A superconducting fault current limiter (SFCL) is a device with a negligible impedance in normal operating conditions that reliably switches to a high impedance state in case of extra-current. Such a device is able to increase the short circuit power of an electric network and to contemporarily eliminate the hazard during the fault. It can be regarded as a key component for future electric power systems. In this paper the state of the art of superconducting fault current limiters mature for applications is briefly resumed and the potential impact of this device on the paradigm of design and operation of power systems is analyzed. In particular the use of the FCL as a mean to allow more interconnection of MV bus-bars as well an increased immunity with respect to the voltage disturbances induced by critical customer is discussed. The possibility to integrate more distributed generation in the distribution grid is also considered. [Copyright &y& Elsevier]

Liquid storage of gaseous fuel on board of vehicles as possible alternative to high-pressure storage is receiving an increasing attention because of the higher mileage, the lower cost of the tank, and the faster refill allowable. The research effort devoted to liquid storage is also boosting the advance of cryogenics on board of vehicles, thus opening the way to the synergic use of superconductors. In such a context, superconducting magnetic energy storage (SMES) for regenerative braking may represent a possible alternative to electrochemical batteries or to developing technologies such as supercapacitors or flywheels. In this paper, the feasibility of SMES for regenerative braking on board of hybrid vehicles with cryogenic fuel tank is investigated. Possible application scenarios are discussed. The design of the superconducting magnet based on commercially available superconducting tapes and the cooling are addressed. The performance of the power control system is also investigated by means of a MATLAB/Simulink simulation model. [ABSTRACT FROM AUTHOR]

The First International Congress on Ayurveda was held in Milan, Italy in March 2009 and it has been the first scientific event of this kind in western world. This groundbreaking international congress was devoted to human being as the product of interactions between Awareness, Environment and Health, subjects that the West tends to consider separate and independent, but that are believed deeply connected in Ayurveda, whose interdependence defines "The Meaning of Life". The Congress established a bridge between indian and western philosophy, scientific and biomedical thinking in order to expand knowledge and healthcare. Main attention and address of the invited speakers was on the concept of "relationships" that, connecting living beings with environment, shape Nature itself. This concept is central in Ayurveda but is also common to other western scientific disciplines such as quantum physics and epigenetics that, in the four Sessions of the Congress, were represented by eminent experts. The importance of this event was underlined by the attendance of more than 400 participants and by noteworthy institutional endorsements, that added a significative political dimension of high social impact due to the topical period for CAM acceptance and integration in Europe. [ABSTRACT FROM AUTHOR]

A magnetization-based formulation of the volume integral equations method for 3-D magnetostatics is discussed. The magnetization of each element is related, via the constitutive law of the material, to the average magnetic flux density within the element rather than to the value at the center as is usually done. This assumption leads to more accurate distribution of magnetization and allows a faster convergence of the solution. Moreover, it leads to more symmetric matrix of the coefficients and reduces the numerical instability due to looping patterns of magnetization, which is inherent to integral methods. The formulation is made effective by the use of a hybrid numerical and analytical approach, which allows for the fast and accurate calculation of the coefficients. The proposed model is validated and compared with the usual model both for saturable and linear material with high susceptibility. [ABSTRACT FROM PUBLISHER]

A novel energy storage system based on a SMES cooled by cryogenic fuel is being developed at the Dept. of Electrical Engineering of the University of Bologna. The system represents an alternative solution with respect to nowadays battery packs for the storage of electrical energy with large specific power. The device may find suitable application on board of road vehicles fed by liquid hydrogen with hybrid power-train (internal combustion engine and electric motor/generation), where a cryogenic tank is already present and no additional cryogenic costs are needed. The housing of the SMES inside the tank used for fuel storage, allows the exploitation of the thermal power required for the continuous evaporation of fuel for feeding the engine to remove the AC losses from the magnet, thus avoiding the need of externally supplied cooling power. In this paper both the design of the magnet and its operation in combination with electronic converter and electric motor/generator during charge/discharge cycles are discussed. Moreover the ongoing activity for the development of a laboratory-scale prototype using MgB2 superconductor is presented. [ABSTRACT FROM AUTHOR]

In large-scale photovoltaic (PV) power plants, the integration of a battery energy storage system (BESS) permits a more flexible operation, allowing the plant to support grid stability. In hybrid PV+BESS plants, the storage system can be integrated by using different power conversion system (PCS) layouts and different charge–discharge strategies. In the AC-coupling layout, the BESS is connected to the ac-side of the system through an additional inverter. In the DC-coupling layout, the BESS is connected to the dc-side, with or without a dedicated dc–dc converter, and no additional inverter is needed. Referring to a 288 MWp PV plant with a 275 MWh BESS, this paper compares the PCS efficiency between AC- and DC-coupling solutions. The power injected into the grid is obtained considering providing primary power-frequency regulation services. A charging and discharging strategy of the BESS is proposed to ensure cyclic battery energy shifting. The power flows in the different components of the system that are obtained under realistic operating conditions, and total energy losses and annual average efficiency are calculated accordingly. Finally, results show a higher efficiency of DC-coupling compared to the AC-coupling layout. [ABSTRACT FROM AUTHOR]

In this paper the design of a superconducting magnet for DC induction heating of aluminum billets is discussed. A split saddle geometry is considered in order to allow a good accessibility of the field area. The layout is obtained by first calculating the field profile needed to produce as uniform a temperature distribution as possible inside the billet at the end of the heating and then by determining the optimum current distribution suitable to produce the required field profile. The operating condition and the final design of the saddle coil are discussed based on present state of the art superconducting wires. [ABSTRACT FROM AUTHOR]

A superconducting magnet with 200 Id stored energy and 75 kW output/input power has been designed and manufactured. The device, which is aimed to power quality enhancement in electric grid, consists of two coaxial coils, counter-series connected in order to keep the stray field below the limit of 0.5 mT. The SC wire is a copper stabilized Nb-Ti strand. Several copper slabs are placed within the coils in order to permit heat removal deep inside the coil, thus allowing cryogen-free cooling and operation at high AC losses regime. Several tests with different ramp rate have been carried out at the liquid helium temperature. Design and manufacturing characteristics as well as test results are discussed in this paper. [ABSTRACT FROM AUTHOR]

Recent progress in material processing has enabled the fabrication of large single grain YBCO hulks having the potential to trap a magnetic field much stronger than that of conventional permanent magnets, thus opening the way to new applications in the field of power electric machinery. However, for YBCO bulks to find a broad use, a suitable magnetization process must be developed. In fact, the value of the trapped field as well as the stability with respect to the time and the shape of the profile strongly depend on the parameters of the magnetization process, i.e. the peak value and the waveform of the applied field and the operating temperature of the bulk. In this paper such a dependence is numerically investigated. [ABSTRACT FROM AUTHOR]

In order to investigate the reciprocal interaction between a SFCL and the Power System an equivalent circuit of the device needs to be introduced in a power system simulator. In this paper the equivalent circuit of a magnetic shield type SFCL, consisting of two coupled electric and thermal networks, is obtained starting from the integral formulation of the coupled electromagnetic-thermal problem inside the device. The numeric waveforms of current and voltage across an SFCL during a fault are calculated and compared with the experimental ones. [ABSTRACT FROM AUTHOR]

In order to investigate how a superconducting fault current limiter (SFCL) can enhance the performance of a power system, an accurate circuit model of the device needs to be introduced in power system simulators. In this paper, we present a ifnite-element numerical model to calculate the time evolution of the voltage across a magnetic-shield-type SF CL, when it is connected to an external circuit. The calculation of the voltage is carried out by using the energy conservation law, and requires the calculation, at any instant, of the current density distribution inside the super- conducting tube and magnetization distribution inside the ferromagnetic core of the device. These distributions are determined by means of two coupled equivalent electric and magnetic circuits, whose topology and components are obtained through the spatial integration of quasi-static form of Maxwell equations. Comparisons between numerical and experimental results are shown. [ABSTRACT FROM AUTHOR]

Presents a numerical model to calculate the distribution of magnetization inside a superconducting bulk when a time-varying magnetic field is applied. Description of the mathematical model; Investigation of the dynamic electromagnetic behavior of a melt-processed ring-shaped superconducting bulk using a pulsed-field magnetization process.

The authors offer observation on developments related to Ayurveda medicine. Topics addressed include the setting up of the International Editorial Office of Ancient Science of Life (ASL) in Europe, the effort to bridge the gap between conventional medicine and the Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy (AYUSH) systems, and the emergence of the so-called Complementary and Alternative Medicine (CAM).

In recent years, the $H$ formulation of Maxwell's equations has become the de facto standard for simulating the time-dependent electromagnetic behavior of superconducting applications with commercial software. However, there are cases where other formulations are desirable, for example for modeling superconducting turns in electrical machines or situations where the superconductor is better described by the critical state than by a power-law resistivity. In order to accurately and efficiently handle these situations, here we consider two approaches based on the magnetic vector potential: the $T$ - $A$ formulation of Maxwell's equations (with power-law resistivity) and the implementation of a quasi critical state model (QCSM) with a steep $E$ - $J$ relationship limited at $J_{\rm c}$. In this article, we extend the $T$ - $A$ formulation to thick conductors so that large coils with different coupling scenarios between the turns can be considered. We also discuss the QCSM in terms of its ability to calculate ac losses: in particular, we investigate the dependence of the calculated ac losses on the frequency of the ac excitation and the possibility of using quick one-step (instead of full-cycle) simulations to calculate the ac losses. [ABSTRACT FROM AUTHOR]

Information about the International Ayurveda Research Seminar on Ayurveda held in Birstein, Germany from September 14 to 15, 2014 is presented. Topics of the seminar include Western and Indian approaches to mental health, the traditional systems of medicine, and the effect of Ayurveda on the recovery in stroke. The event featured several professors including Antonella delle Fave, Torkel Falkenberg, and Bernard Uehleke.

This paper investigates the conditions of use and the equivalence of various constitutive laws used to model the electromagnetic behavior of high-temperature superconductors: two versions of the critical state model (CSM), the power law model, and a so-called percolation model. All these models can be used to represent the same superconducting material with some limit of accuracy. The CSM and the power law model are well known in the literature. The percolation model can be seen as a generalization of the power law model that includes also a CSM-like behavior at very low electric fields. The investigation has been carried out for three types of operating conditions: the sudden application of a dc excitation, a pure ac excitation, and combined dc and ac excitations. The equivalence between the different constitutive laws is shown to be a function of the magnitude of the electric fields and of the time scales involved. In the dc case, long time scales and very small electric fields are predominant; thus, the superconductor requires a model that is accurate at low electric fields, such as the percolation model. The losses then arise from the relaxation of the magnetic field in the sample. In the ac case, the power law and percolation models are nearly identical when considering power frequencies, so choosing the simpler power law model is fully acceptable in practice. In addition, the CSM coincidentally provides good predictions of the losses in the power frequency range. In the dc+ac case, when time scales in the range of minutes to hours are considered, it is shown that ac losses dominate over relaxation losses, and the same conclusions as for the ac case apply. [ABSTRACT FROM AUTHOR]

More than a century after the discovery of superconductors (SCs), numerous studies have been accomplished to take advantage of SCs in physics, power engineering, quantum computing, electronics, communications, aviation, healthcare, and defence-related applications. However, there are still challenges that hinder the full-scale commercialization of SCs, such as the high cost of superconducting wires/tapes, technical issues related to AC losses, the structure of superconducting devices, the complexity and high cost of the cooling systems, the critical temperature, and manufacturing-related issues. In the current century, massive advancements have been achieved in artificial intelligence (AI) techniques by offering disruptive solutions to handle engineering problems. Consequently, AI techniques can be implemented to tackle those challenges facing superconductivity and act as a shortcut towards the full commercialization of SCs and their applications. AI approaches are capable of providing fast, efficient, and accurate solutions for technical, manufacturing, and economic problems with a high level of complexity and nonlinearity in the field of superconductivity. In this paper, the concept of AI and the widely used algorithms are first given. Then a critical topical review is presented for those conducted studies that used AI methods for improvement, design, condition monitoring, fault detection and location of superconducting apparatuses in large-scale power applications, as well as the prediction of critical temperature and the structure of new SCs, and any other related applications. This topical review is presented in three main categories: AI for large-scale superconducting applications, AI for superconducting materials, and AI for the physics of SCs. In addition, the challenges of applying AI techniques to the superconductivity and its applications are given. Finally, future trends on how to integrate AI techniques with superconductivity towards commercialization are discussed. [ABSTRACT FROM AUTHOR]

In several cases, substations have become incapable of supporting faults due to increase in short-circuit levels. Fault current limiters (FCLs) are a potential solution for this problem. Among several FCL topologies presented in the literature, the saturated iron core superconducting fault current limiter (SIC-SFCL) has shown promising results in real tests in substations. In this context, this article presents the impacts of different kinds of short circuit on the SIC-SFCL device. To reproduce various types of fault, the SIC-SFCL is modeled in a 3-D framework considering both ferromagnetic and superconducting nonlinearities. Moreover, the proposed 3-D finite-element method model can couple the SIC-SFCL to the electric power system, also representing the electrical grid and the protection systems. For this investigation, the dc-bias superconducting coil’s normalized current density and the iron cores’ magnetic flux density are examined in light of different kinds of short circuit. The simulations are compared with measurements in a bench prototype, showing a maximum error of 16.5%. Furthermore, different types of short circuit are investigated and compared, which is possible only using a 3-D model. The highest limitation occurs in the phase-to-phase short-circuit case. In the dc circuit of the SIC-SFCL, the highest transient period happens in the single-phase short circuit. Finally, the phase-to-phase fault presents the highest dc current during the transient. [ABSTRACT FROM AUTHOR]

Background: Ayurveda is widely practiced in South Asia in the treatment of osteoarthritis (OA). The aim of these secondary data analyses were to identify the most relevant variables for treatment response and group differences between Ayurvedic therapy compared to conventional therapy in knee OA patients. Methods: A total of 151 patients (Ayurveda n = 77, conventional care n = 74) were analyzed according to the intention-to-treat principle in a randomized controlled trial. Different statistical approaches including generalized linear models, a radial basis function (RBF) network, exhausted CHAID, classification and regression trees (CART), and C5.0 with adaptive boosting were applied. Results: The RBF network implicated that the therapy arm and the baseline values of the WOMAC Index subscales might be the most important variables for the significant between-group differences of the WOMAC Index from baseline to 12 weeks in favor of Ayurveda. The intake of nutritional supplements in the Ayurveda group did not seem to be a significant factor in changes in the WOMAC Index. Ayurveda patients with functional limitations > 60 points and pain > 25 points at baseline showed the greatest improvements in the WOMAC Index from baseline to 12 weeks (mean value 107.8 ± 27.4). A C5.0 model with nine predictors had a predictive accuracy of 89.4% for a change in the WOMAC Index after 12 weeks > 10. With adaptive boosting, the accuracy rose to 98%. Conclusions: These secondary analyses suggested that therapeutic effects cannot be explained by the therapies themselves alone, although they were the most important factors in the applied models. [ABSTRACT FROM AUTHOR]

The article discusses the COVID-19 pandemic has fuelled global initiatives to develop vaccines and identify pharmacotherapies. Topics include the National Institute of Health Clinical Trials website lists 3489 clinical trials as of September 30, 2020; and according to the World Health Organization International Clinical Trials Registry Platform website, ‘‘has a need to ensure all inform decisions about the health care.

The high-Tc superconducting (HTS) dynamo is a promising device that can inject large DC supercurrents into a closed superconducting circuit. This is particularly attractive to energise HTS coils in NMR/MRI magnets and superconducting rotating machines without the need for connection to a power supply via current leads. It is only very recently that quantitatively accurate, predictive models have been developed which are capable of analysing HTS dynamos and explain their underlying physical mechanism. In this work, we propose to use the HTS dynamo as a new benchmark problem for the HTS modelling community. The benchmark geometry consists of a permanent magnet rotating past a stationary HTS coated-conductor wire in the open-circuit configuration, assuming for simplicity the 2D (infinitely long) case. Despite this geometric simplicity the solution is complex, comprising time-varying spatially-inhomogeneous currents and fields throughout the superconducting volume. In this work, this benchmark problem has been implemented using several different methods, including H -formulation-based methods, coupled H - A and T - A formulations, the Minimum Electromagnetic Entropy Production method, and integral equation and volume integral equation-based equivalent circuit methods. Each of these approaches show excellent qualitative and quantitative agreement for the open-circuit equivalent instantaneous voltage and the cumulative time-averaged equivalent voltage, as well as the current density and electric field distributions within the HTS wire at key positions during the magnet transit. Finally, a critical analysis and comparison of each of the modelling frameworks is presented, based on the following key metrics: number of mesh elements in the HTS wire, total number of mesh elements in the model, number of degrees of freedom, tolerance settings and the approximate time taken per cycle for each model. This benchmark and the results contained herein provide researchers with a suitable framework to validate, compare and optimise their own methods for modelling the HTS dynamo. [ABSTRACT FROM AUTHOR]

This paper describes the main characteristics and the performance of a saturated core type fault current limiter (FCL) rated 45 MVA (33 kV-800 A) to be provided by ASG Power Systems. The FCL, which has been submitted to preliminary laboratory testing, will be installed at a 275/33 kV substation in the U.K. and will reduce the fault current by 38%. The device is based on an open geometry of the magnetic cores which allows reduced size and the weight. Magnetic saturation of the cores is obtained by means of two magnesium diboride (MgB2) magnets. A numerical model of the FCL has been developed and validated and the interaction of the device with the power grid has been investigated. Details and results of the model are also discussed in the paper. [ABSTRACT FROM PUBLISHER]

Background: Traditional Indian Ayurvedic medicine uses complex treatment approaches, including manual therapies, lifestyle and nutritional advice, dietary supplements, medication, yoga, and purification techniques. Ayurvedic strategies are often used to treat osteoarthritis (OA) of the knee; however, no systematic data are available on their effectiveness in comparison with standard care. The aim of this study is to evaluate the effectiveness of complex Ayurvedic treatment in comparison with conventional methods of treating OA symptoms in patients with knee osteoarthritis. Methods and design: In a prospective, multicenter, randomized controlled trial, 150 patients between 40 and 70 years, diagnosed with osteoarthritis of the knee, following American College of Rheumatology criteria and an average pain intensity of ⩾40 mm on a 100 mm visual analog scale in the affected knee at baseline will be randomized into two groups. In the Ayurveda group, treatment will include tailored combinations of manual treatments, massages, dietary and lifestyle advice, consideration of selected foods, nutritional supplements, yoga posture advice, and knee massage. Patients in the conventional group will receive self-care advice, pain medication, weight-loss advice (if overweight), and physiotherapy following current international guidelines. Both groups will receive 15 treatment sessions over 12 weeks. Outcomes will be evaluated after 6 and 12 weeks and 6 and 12 months. The primary endpoint is a change in the score on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) after 12 weeks. Secondary outcome measurements will use WOMAC subscales, a pain disability index, a visual analog scale for pain and sleep quality, a pain experience scale, a quality-of-life index, a profile of mood states, and Likert scales for patient satisfaction, patient diaries, and safety. Using an adapted PRECIS scale, the trial was identified as lying mainly in the middle of the efficacy-effectiveness continuum. Discussion: This trial is the first to compare the effectiveness of a complex Ayurvedic intervention with a complex conventional intervention in a Western medical setting in patients with knee osteoarthritis. During the trial design, aspects of efficacy and effectiveness were discussed. The resulting design is a compromise between rigor and pragmatism. [ABSTRACT FROM AUTHOR]

The experimental investigation of the levitation force between a Permanent magnet (PM) and MgB2 disk prepared by means of the Reactive Mg Liquid Infiltration is presented. Both FC and ZFC levitation in the temperature range from 21 K to 37 K are considered. The long term behavior of the levitation force is also investigated. A numerical model is developed in order to investigate the electrodynamics of levitation. The hysteretic behavior of the levitation force is related to the dynamic of current penetration inside the MgB2 disk by means of the numerical model. [ABSTRACT FROM AUTHOR]

Superconducting Fault Current Limiters (SFCLs) are regarded as key components for modern power systems. The progress in the development of YBCO thin films opens new perspectives in the design of these devices. In this paper, the quenching phenomenon in YBCO thin films is investigated experimentally, in order to gain the proper technical know-how suitable for the design of resistive type SFCLs. In particular, the origin of the quenching, as well as the propagation dynamics within a YBCO tape, is investigated for different input current waveforms. The role of a parallel-connected protective resistance on the quench dynamic is also studied. [ABSTRACT FROM AUTHOR]

We have analyzed the characteristics of dc-induction heating of aluminium billets both numerically and experimentally and developed a numerical model for the calculation of the power and temperature distributions inside the billet during the heating. We validated the model by comparison with the experimental results from a laboratory-scale prototype using permanent magnets. We studied the heating process of a real scale system by means of the model, taking into account the weakening of the mechanical properties during the heating. We provide an example of design of an industrial scale dc induction heater. [ABSTRACT FROM AUTHOR]

Background: Traditional Indian Ayurvedic medicine uses complex treatment approaches, including manual therapies, lifestyle and nutritional advice, dietary supplements, medication, yoga, and purification techniques. Ayurvedic strategies are often used to treat osteoarthritis (OA) of the knee; however, no systematic data are available on their effectiveness in comparison with standard care. The aim of this study is to evaluate the effectiveness of complex Ayurvedic treatment in comparison with conventional methods of treating OA symptoms in patients with knee osteoarthritis.Methods and Design: In a prospective, multicenter, randomized controlled trial, 150 patients between 40 and 70 years, diagnosed with osteoarthritis of the knee, following American College of Rheumatology criteria and an average pain intensity of ≥40 mm on a 100 mm visual analog scale in the affected knee at baseline will be randomized into two groups. In the Ayurveda group, treatment will include tailored combinations of manual treatments, massages, dietary and lifestyle advice, consideration of selected foods, nutritional supplements, yoga posture advice, and knee massage. Patients in the conventional group will receive self-care advice, pain medication, weight-loss advice (if overweight), and physiotherapy following current international guidelines. Both groups will receive 15 treatment sessions over 12 weeks. Outcomes will be evaluated after 6 and 12 weeks and 6 and 12 months. The primary endpoint is a change in the score on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) after 12 weeks. Secondary outcome measurements will use WOMAC subscales, a pain disability index, a visual analog scale for pain and sleep quality, a pain experience scale, a quality-of-life index, a profile of mood states, and Likert scales for patient satisfaction, patient diaries, and safety. Using an adapted PRECIS scale, the trial was identified as lying mainly in the middle of the efficacy-effectiveness continuum.Discussion: This trial is the first to compare the effectiveness of a complex Ayurvedic intervention with a complex conventional intervention in a Western medical setting in patients with knee osteoarthritis. During the trial design, aspects of efficacy and effectiveness were discussed. The resulting design is a compromise between rigor and pragmatism.Trial Registration: NCT01225133. [ABSTRACT FROM AUTHOR]