Magnetically resonant wireless power transfer (WPT) technique excels in delivering power over a relatively long distance, and WPT systems for bio-implants have been successfully developed. However, ...the preconception of resonant-operating results in a fact that most previous works pay little attention to the optimization of the compensate capacitors; these design methods cannot meet the newly arisen challenges when designing a high-power wireless charging system (WCS) for electric vehicles (EVs). This paper presents a design method featuring compensate capacitor optimizing for better design of practical kilowatt-level WCS. Comparison with conventional frequency tuning method is made based on equivalent circuit model analysis. Compensating characteristics of a typical WCS are studied to find out how the compensate capacitors affect the systemic performance. Furthermore, considering peculiar constraints and requirements of EV-oriented WCS, we present detailed optimizing procedure and adjustment criterion. Finally, correctness and effectiveness of the proposed optimizing method are verified by a 3.3-kW wireless charging prototype. A transfer efficiency value of 92% over 21 cm and 88.5% over 36 cm is achieved; voltages of the transmit and receive coils are simultaneously minimized and balanced for security.
Normalization of citation scores using reference sets based on Web of Science subject categories (WCs) has become an established (“best”) practice in evaluative bibliometrics. For example, the Times ...Higher Education World University Rankings are, among other things, based on this operationalization. However, WCs were developed decades ago for the purpose of information retrieval and evolved incrementally with the database; the classification is machine‐based and partially manually corrected. Using the WC “information science & library science” and the WCs attributed to journals in the field of “science and technology studies,” we show that WCs do not provide sufficient analytical clarity to carry bibliometric normalization in evaluation practices because of “indexer effects.” Can the compliance with “best practices” be replaced with an ambition to develop “best possible practices”? New research questions can then be envisaged.
•Geometry comparison between ITER-WCLL-WCS and Water Loop.•Water Loop secondary loop has some differences from ITER-WCLL-WCS.•Water loop is capable to reproduce the WCLL-WCS normal operational ...state.•LOFA affecting the secondary loop is investigated as incidental transient.•Few differences between the two facilities due to the geometrical differences.
The Water-Cooled Lead-Lithium (WCLL) is one of the two candidate concepts for the Breeding Blanket (BB) of DEMO. A Test Blanket Module (TBM) together with its Water Cooling System (WCS) is going to be installed and tested in the ITER reactor. The WCS acts as primary cooling circuit of the TBM module, and it is designed to reproduce the water thermodynamic conditions expected at the DEMO BB inlet.
During last years, ENEA and the DIAEE of Sapienza University of Rome have carried out the conceptualization of the Water Loop (WL) facility, belonging to the W-HYDRA experimental platform planned at C.R. Brasimone. The W-HYDRA platform is composed by three individual facilities called: Water Loop, Steam, and LIFUS5/Mod4. Water Loop replicates the salient thermal-hydraulic features of the ITER WCLL WCS, and it is equipped with a test section placed inside a Vacuum Vessel (VV) to investigate mock-ups of the whole TBM or its individual parts.
This paper assesses the relevancy of the WL facility with respect to ITER WCLL TBM System comparing their thermal-hydraulic performances during selected operational and accidental conditions. Two RELAP5/Mod3.3 models were developed, and the outcomes of the simulations showed a good agreement, thus demonstrating the effectiveness of WL facility to support the ITER TBM program.
This paper deals with a Wind Conversion System (WCS) based on a Hybrid Excitation Synchronous Generator (HESG) connected to an isolated load. The set is modeled under Matlab–Simulink. To ensure an ...efficient and reliable use of the system, a tight control remains vital. In fact, the dynamic equations of a turbine are strongly nonlinear as are the ones of a HESG; most of the system parameters are highly uncertain, and, at last, a WCS is always affected by disturbance sources such as load variances, harmonics, mechanical vibrations…To address these problems, robust control methods must be adopted. In this paper, two strategies for the control of variable speed wind turbine are investigated. First, an H∞ controller is implemented. Then, a second-generation CRONE controller is designed. The performance of the two regulators is compared with respect to the tracking of the optimal rotation speed, the attenuation of the mechanical vibration and the robustness to the uncertainty of the parameters, using time-domain simulations. It has been found that the CRONE controller is more robust to parameters uncertainty and minimizes the fluctuations of the torsional torque and the generator’s angular velocity. Finally, an experimental validation of the velocity controllers is presented to complete the simulation results and fully validate the chosen approach.
Although remarkable progress has been made on single-image super-resolution (SISR), deep learning methods cannot be easily applied to real-world applications due to the requirement of its heavy ...computation, especially for mobile devices. Focusing on the fewer parameters and faster inference SISR approach, we propose an efficient and time-saving wavelet transform-based network architecture, where the image super-resolution (SR) processing is carried out in the wavelet domain. Different from the existing methods that directly infer high-resolution (HR) image with the input low-resolution (LR) image, our approach first decomposes the LR image into a series of wavelet coefficients (WCs) and the network learns to predict the corresponding series of HR WCs and then reconstructs the HR image. Particularly, in order to further enhance the relationship between WCs and image deep characteristics, we propose two novel modules wavelet feature mapping block (WFMB) and wavelet coefficients reconstruction block (WCRB) and a dual recursive framework for joint learning strategy, thus forming a WCs prediction model to realize the efficient and accurate reconstruction of HR WCs. Experimental results show that the proposed method can outperform state-of-the-art methods with more than a <inline-formula> <tex-math notation="LaTeX">2\times </tex-math></inline-formula> reduction in model parameters and computational complexity.
By the CF «Hope and rescue» in Simferopol in 2010 was realised one of the first projects in the world-the pilot project on the HIV prevention among the women of commercial sex (WCS) with the help of ...the model «Peer Driven Intervention». Primary purpose of this intervention was involving of new clients especially from priority difficult of access groups, providing the clients with new and comprehensive knowledge’s on the HIV, STD prevention and less risky sexual behaviour. Introduction of the project on HIV prevention among WCS by a model «PDI» was very urgent for the region because the majority of the WCS are part of the so-called «closed group». It is very difficult to involve these women in participating of the projects on HIV and STD prevention, overcome services of the programme «Harm reduction». The women of commercial sex, which were not the clients of the project «Harm reduction», were the target group of the project. The priority group included women of commercial sex at the age to 25 years inclusive. The peculiarity of the model «PDI» consisted in that every participant of the project got the possibility to take part independently in measures on prevention in their own community. In the project women are interviewed, taught and get preventive services. Model «PDI» provides a motivational gift for every client for passing of the interview, nominal money fee for involving of WCS from a priority group and gifts for the successful teaching of WCS from their community. With the help of the project we managed to involve 544 clients which later became the clients of the project «Harm reduction». Together with active participating of WCS in the preventive programmes the very important result of the project revealed in a changing of the behaviour for less risky.
Thermal management of magnetic coils is essential for the safe and stable operation of high-power wireless charging systems (WCS). Upon a deficiency of detailed thermal analysis, this article ...presents a thermal model under natural convection featuring both accuracy and simplicity. Analysis shows that the loss distribution between different parts of the coil has little effect on the resultant temperature. This in the context leads to a key conclusion that the maximum allowable power loss density decreases in an m -1/8 relationship with the increasing area gain m , given the coil geometry and natural convective condition. It also indicates that the coil set can be thermally treated as a black-box to predict how the temperature would rise and determine the necessary coil area for heat dissipation. These conclusions provide guidelines for the material and structure choices of the coils as well as for flexible scaling design. The proposed model is verified by simulation and experiment studies on a 5 kW prototype. The maximum error of temperature estimation is shown to be 9.5%.
The reliable prediction of long-term creep life is of great importance in order to ensure the service safety of high-temperature components. In this work, the novel Wilshire-Cano-Stewart (WCS) ...relationships were introduced to model the creep behavior and predict the long-term creep life of P91 steel based on the short-term creep data. The accelerated creep experiments were firstly carried out at the temperature range of 580–620 °C, while the stresses varied from 135 to 200 MPa. According to the analyses of normalized-mean-squared error (NMSE) and mean logarithmic error (MLE), it demonstrated that the WCS model can express all the obtained creep data very well due to the average relative errors lower than 10%. Meanwhile, these values are much lower than those of traditional Time-Temperature-Parameter (TTP) models. In addition, the WCS model can provide the reasonable estimates of 200,000 h creep life with accelerated creep measurements lasting up to only 2000 h.
•WCS model made full use of Wilshire and Sinh model respective advantages and eliminated known weaknesses.•Results of WCS model are better than the traditional L-M model in life prediction.•Results of WCS model are accurate enough in life prediction.
: To understand mean (WCS
) and peak (WCS
) worst case scenarios within training and game play in male professional soccer.
: Thirty-one (
= 31) first team players were monitored across 37 matches ...and 14 MD-3 sessions. Playing status was distinguished, football drills analyzed, and performance explored in long-period: >6 days, moderate-period: 5-6 days, and congested-period: ≤4 days. Relative total distance (TD), high-speed running distance (HSRD, >19.8 km·h
), sprint distance (SD, >25.2 km·h
), accelerations/decelerations (A+D, >3 m·s
), accelerations (Acc, >3 m·s
), and decelerations (Dec, >-3 m·s
) were measured as well as Maximum acceleration (Max Acc; m·s
) and deceleration (Max Dec; m·s
).
: Analysis of variance found differences between matches and training in WCS
for TD, HSRD, SD, and Max Dec in all positions (
< .001; partial η
> .275). Fullbacks displayed differences between match and training in Max Acc (moderate ESs;
< .001), while center backs and central midfielders in Max Dec (large ESs;
> .05). Main effects of playing status were discovered for all metrics except Max Dec (
< .001; partial η
> .124). Analysis showed differences between long- and congested-period for A+D and Dec (large ESs;
≤ .05).
: Findings provide more insights into short peak intensity demands of soccer showing that the maximum high velocity action of acceleration and deceleration is not being replicated in training. Nonstarters lack maximum intensity exposure in matches (WCS
) increasing the gap between training and competition even higher during congested fixture periods.
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