Miracle-dz/UniFAR-FTUs huggingface dataset:
FACTS Providing Grid Services: Applications and Testing

The role of flexible alternating current transmission systems (FACTSs) in the provision of grid services is becoming increasingly important, due to the massive integration of intermittent renewable energy sources, energy storage systems, and the decommissioning of thermal plants. A comprehensive literature review of grid services offered by FACTS is performed, focusing on the different grid services that they can provide, such as power flow control, reactive power control, voltage control, power quality improvement, harmonic mitigation, improvement of transient stability, and damping of inter-area and intra-area oscillations. These grid services need to be realistically and economically validated in suitable testing environments. A review of relevant standards, guides, and the literature is performed, which covers the entire range from functional specification and factory testing up to the field testing of FACTS. Advanced industry practices, such as controller hardware in the loop (CHIL) testing of FACTS controllers by the manufacturer, and recent trends, such as CHIL testing of replica controllers by the owner, are underlined. Limitations of conventional testing and CHIL testing are explained and the use of power hardware in the loop (PHIL) simulation for FACTS testing is discussed. CHIL and scaled-down PHIL tests on a transmission static synchronous compensator (STATCOM) are performed and a comparison of the results is presented.
Tracked Wall-Climbing Robot for Calibration of Large Vertical Metal Tanks

Large vertical metal tanks are the primary vessels for the storage and turnover of crude oil, and the accuracy of their capacity calibrations are of great significance. The optical reference line method (ORLM) is used for capacity calibration and is time-consuming, labor-intensive, and hazardous, because of the elevated work. This paper aims to present a robot to overcome the problems above. We propose a tracked wall-climbing robot (TWCR) with permanent magnetic adhesion tracks, a collapsible scale, and an optional shovel-like rust remover that enable the TWCR to move stably on tank surfaces and perform the ORLM. Two sets of field tests (internal ORLM and external ORLM) indicate that capacity calibration by the TWCR is time saving, convenient, and safe, in addition to being accurate and reliable.
Effects of the Current Direction on the Energy Production of a Tidal Farm: The Case of Raz Blanchard (France)

This study aims to investigate the influence of the current direction on the energy production of a tidal turbines array. It is based on a three-dimensional (3D) numerical simulation of the flow where the turbines are represented with actuator disks. The case study consists of modelling the energy extraction of a small array of turbines (staggered and aligned layouts) placed in the Raz Blanchard (Alderney Race, France). The simulations are performed with hydrodynamic data (current magnitude and direction) representative of a mean tide, with several resistance forces and ambient turbulence intensities. The influence of the current direction on the energy production is highlighted by comparing the simulations forced with the real current direction with those in which the angle of incidence between the incoming flow and the turbine’s axis is “switched off” (bi-directional flow). When the flow is aligned with the turbines’ axis (misalignment “switched off”), the staggered layout produces more than the aligned arrangement. Comparison of the two types of simulations (misalignment switched off or not) shows that the misalignment of the flow around a predominant direction reduces the energy produced by the staggered layout and increases the production of the aligned layout. Furthermore, it suggests that the mean energy produced per machine is almost the same for both layouts. Higher turbulence intensity reduces the positive effect of the directional spreading on the aligned layout production and limits the negative effect on the staggered layout production.
Solution-Processed DyOx for Aging Diffusion ZnSnO Transistors and Applications in Low-Voltage-Operating Logic Circuits

Metal–oxide high-<inline-formula> <tex-math notation="LaTeX">${k}$ </tex-math></inline-formula> material is regarded as the promising building block for large area high-performance flexible electronic devices. Here, we report that dysprosium oxide (DyO<sub><italic>x</italic></sub>) films were successfully integrated as dielectrics into thin-film transistors (TFTs) for the first time. Solution-driven DyO<sub><italic>x</italic></sub> films behave high transmittance over 85% and imply the possible application in transparent devices. Measurements based on 500 °C annealing ZnSnO/DyO<sub><italic>x</italic></sub> TFTs have indicated the dramatic improvement in electrical performance after natural aging diffusion for 10 days, containing the increased saturation mobility value from 0.57 to 2.5 cm<inline-formula> <tex-math notation="LaTeX">$^{{2}}\cdot \text{V}^{-{1}}\cdot \text{s}^{-{1}}$ </tex-math></inline-formula> and the lifted current ON/ OFF ratio from <inline-formula> <tex-math notation="LaTeX">$7.8\times 10^{{4}}$ </tex-math></inline-formula> to <inline-formula> <tex-math notation="LaTeX">$2.4\times 10^{{6}}$ </tex-math></inline-formula>. It is worth mentioning that the mobility of aging samples with the lower annealing temperature of 420 °C even surpasses the aforementioned 500 °C annealing without aging TFTs. The variable-range-hopping (VRH) percolation model and coherent interface theory are used to explore electronic transport mechanism for amorphous and polycrystalline ZnSnO films, respectively. Finally, the resistor-loaded inverter has been fabricated and revealed the gain of 7.3 at the low voltage of 2.5 V, which even surpasses many In-based TFT devices. It can be concluded that the solution-based samples can proceed with 10 days aging treatment before encapsulation to obtain the stable electrical performance, which affords a simple and effective approach toward building low-temperature, low power consumption transparent electronic devices.
Performance Comparison of User Interface Devices for Controlling Mining Software in Virtual Reality Environments

Recently, many studies have been conducted to apply virtual reality (VR) technology to the mining industry. To accomplish this, it is necessary to develop user interface devices that can effectively control software. Most VR content in the mining industry requires precise device control for equipment operation or accident response. In this study, we compare the performance of four user interface devices (a 2D mouse, 2D & 3D mice, a VR controller, and a Kinect (Microsoft) sensor and bend-sensing data glove) for controlling mining industry software in a VR environment. The total working time, number of device clicks and click accuracy, were analyzed based on 10 experimenters performing 3D orebody modeling, using each device in the VR environment. Furthermore, we conducted a survey to evaluate the ease of learning, ease of use, immersion and fatigue of each device after the experiment. The results show that the 2D mouse yields a high performance in terms of its working time, click accuracy, ease of learning and ease of use. However, the 2D mouse did not completely leverage the VR environment, owing to low user immersion. The Kinect sensor and bend-sensing data glove could control the software efficiently while maximizing user immersion. Our findings are expected to provide a useful reference for the future development of user interface devices in the mining industry.
Transmission of 160-Gb/s Modified Manchester modulation over WDM system

ABSTRACT The paper examines the performance of Modified Manchester (MM) modulation scheme over wavelength division multiplexing (WDM) in high-speed optical communication links. The MM as a new modulation technique has a narrow spectral width compared to conventional Manchester coding, which allows its implementation in WDM systems beneficial. In this study, the performance characteristics of MM and conventional Manchester modulation formats are assessed in WDM system at 10 Gb/s bitrate for each channel, for the least allowable channel spacing as well as tolerance to chromatic dispersion (CD). It is revealed from the results of simulation that MM performs meaningfully well in comparison with conventional Manchester in terms of tolerance against narrow optical filtering, spectral efficiency, which is improved by 32% and CD tolerance, which is improved by +100 ps/nm. Sixteen wavelength channels (16 × 10 Gb/s) are modulated to provide 160 Gb/s data capacity, which was transmitted successfully over 224 km standard single mode fibre (SSMF) using MM while the conventional Manchester only covered about 157 km.
Survey on magnetic resonant coupling wireless power transfer technology for electric vehicle charging

Wireless Power Transfer technology (WPT) makes it possible to supply power through an air-gap, without the need for current-carrying wires. One important technique of WPT technology is magnetic resonant coupling (MRC) WPT. Based on the advantages of MRC WPT, such as safety and high power transfer efficiency over a long transmit distance, there are many possible applications of MRC WPT. This paper provides a comprehensive, state-of-the-art review of the MRC WPT technology and wireless charging for electric vehicle (EV). A comparative overview of MRC WPT system design which includes a detailed description of the prototypes, schematics, compensation circuit topologies (impedance matching), and international charging standards. In addition, this paper provides an overview of wireless EV charging including the static wireless EV charging and the dynamic wireless EV charging, which focuses on the coil design, power transfer efficiency, and current research achievement in literature.
Study on creep mechanism of coral sand based on particle breakage evolution law

The time-dependent deformation property of backfill coral sand is of great important to the long-term stability of engineer facilities bulit on reefs and reclaimed land. In order to investigate the long-term deformation behavior, one-dimensional compression creep tests under different constant stresses were carried out for coral sand taken from a reef in the South China Sea by WG type high-pressure consolidation instrument. The test results show that under the action of constant stress, coral sand has a strong deformation timeliness and shows remarkable nonlinear attenuation creep characteristics. The creep of coral sand has obvious stages and has gone through three stages of instantaneous deformation, accelerated deformation and slow deformation phase tending to stability. The relationship of strain-time can be fitted with power function in mathematic. The particle breakage state of any single particle size group of coral sand after creep can be well described by using the two-parameter Weibull distribution function, Weibull parameters a and b have a good exponential relationship with stress, and have a negative linear relation with quantitative index Br of particle breakage, and have a negatively correlated with final total strain. Under the action of low stress level, the main cause of creep deformation is the movement and recombination of particles. At low stress level, the movement and recombination of particles are the main reason of creep deformation, while at high stress level, the slippage and filling pores of broken coral sand particles are the main reason of creep deformation.
A Traffic Assignment Model Based on Link Densities

A new model is presented that determines the traffic equilibrium on congested networks using link densities as well as costs in a manner consistent with the fundamental traffic equation. The solution so derived satisfies Wardrop’s first principle. This density-based approach recognizes traffic flow reductions that may occur when network traffic congestion is high; also, it estimates queue lengths (i.e., the number of vehicles on saturated links), and it explicitly takes into account the maximum flow a link can handle, which is defined by the fundamental traffic equation. The model is validated using traffic microsimulations and implemented on a typical Nguyen-Dupuis network to compare it with a flow-based approach. System optimal assignment model based on link densities is also presented.
Discrete and Phase Field Methods for Linear Elastic Fracture Mechanics: A Comparative Study and State-of-the-Art Review

Three alternative approaches, namely the extended/generalized finite element method (XFEM/GFEM), the scaled boundary finite element method (SBFEM) and phase field methods, are surveyed and compared in the context of linear elastic fracture mechanics (LEFM). The purpose of the study is to provide a critical literature review, emphasizing on the mathematical, conceptual and implementation particularities that lead to the specific advantages and disadvantages of each method, as well as to offer numerical examples that help illustrate these features.
Nucleon electromagnetic form factors and electroexcitation of low lying nucleon resonances in a light-front relativistic quark model

We utilize a light-front relativistic quark model (LF RQM) to predict the 3q core contribution to the electroexcitation amplitudes for the {Delta}(1232)P{sub 33}, N(1440)P{sub 11}, N(1520)D{sub 13}, and N(1535)S{sub 11} up to Q{sup 2} = 12 GeV{sup 2}. The parameters of the model have been specified via description of the nucleon electromagnetic form factors in the approach that combines 3q and pion-cloud contributions in the LF dynamics.
Experimental diagnosis of multiple faults on a rotor-stator system by fast Fourier transform and wavelet scalogram

This paper presents the recent application of the scalogram of Continuous Wavelet Transform (CWT) as a vibration monitoring and signal processing tool for a rotor dynamic response under parametric excitation. The experimental test data of coupled lateral-torsional vibrations of a rotor-stator system with transverse crack was obtained through a data acquisition set-up interfaced with Rotor-Kit-4 (RK-4). Analysis was executed on rotor deflection, orbit, frequency and time-frequency spectrum of the RK-4 experimental data. The scalograms of CWT were used experimentally to represent the aperiodic occurrence of rub between the rotor-stator and crack features. Variation in 3-D scalogram peaks in the presence of rub and crack were unique and were used to distinguish quasi-periodic motion from other types of motion. An unbalanced cracked rotor gave a higher frequency amplitude response compared to an unbalanced rotor with rub under the same conditions. Irregularities in orbit orientation near sub-harmonic resonances were observed in the test data. Multiple rebounds inside the orbit loop were unique rub indicators. Conspicuous horizontal components of the higher harmonics were observed near the critical speed when a crack existed. CWT established inherent feature patterns that discriminated unbalance, rub and a crack.
Short-Term Wind Speed Interval Prediction Based on Ensemble GRU Model

Wind speed interval prediction is playing an increasingly important role in wind power production. The intermittent and fluctuant characteristics of wind power make high-quality prediction interval challenging. In this paper, a novel hybrid model based on a gated recurrent unit neural network and variational mode decomposition is proposed for wind speed interval prediction. Initially, variational mode decomposition is employed to decompose the complex wind speed time series into simplified modes. Interval prediction model and a point prediction model based on a gated recurrent unit neural network are designed to conduct interval prediction in primary mode and point prediction in rest modes, respectively, before the composition and construction of the prediction interval. Then, an error prediction model based on a gated recurrent unit neural network is proposed to enhance the model performance by error correction. Eight cases from two wind fields are used to test and verify the proposed method. The results indicate that the proposed method is a highly qualified method that has a much higher prediction interval coverage probability and narrower prediction interval width.
Textiles and Fabrics for Enhanced Structural Glass Facades: Potentials and Challenges

The use of textiles in architecture can cover a wide set of solutions and functions, spanning from buildings, towards geotechnical, aeronautic or automotive fields, etc. Special applications involve textiles in the health care or dressing scenarios. A multitude of other functions can then be found relatively for the use of textiles in building engineering and facades. As far as traditional facades or roofs composed of glass are taken into account, textiles offer a relevant number of potential uses that are specifically focused on energy, acoustic, insulation and even structural goals, in addition to pure architectural objectives. It is known that glass is relatively versatile, but has intrinsic needs and thermo-physical and mechanical features that require dedicated design methods, towards safe design purposes. Glass itself, in the form of constructional material, cannot be directly compared to other consolidated solutions for buildings. The same concept applies to textiles, and to their use to enhance other building components. Besides the key advantages deriving from the use of textiles in glass facades and envelopes—in the form of light, thermal or acoustic insulation, or energy efficiency—special care must be spent for specific structural requirements and performances. In some cases, textiles can in fact offer enhanced resistance to ordinary glass structures. In other conditions, textiles in combination with glass can ensure also enhanced acoustic and thermal performances. A multidisciplinary design approach able to properly fit several objectives should be considered. This paper aims at exploring the actual knowledge on glass textiles, with a focus on available tools and research trends, with careful consideration for structural glass facade applications.
Transmit Signal Design for Large-Scale MIMO System With 1-bit DACs

Deploying low-resolution (e.g. one-bit) digital-to-analog converters (DACs) is of great importance in the multiple-input multiple-output (MIMO) system equipped with a large-scale antenna array since such a hardware architecture brings low-cost and circuit power saving for each antenna. In this paper, the problem of transmit signal design in a large-scale MIMO system with 1-bit DACs is investigated. To ensure directional transmission, we propose to design the transmit signal by minimizing the weighted mean-squared error (MSE) between the formed beampattern and a given one. The resulting design problem, which involves a nonconvex fourth-order objective and a set of nonconvex discrete constraints, is NP-hard, and therefore, an alternating minimization (AM) method is devised. In order to obtain a high-quality 1-bit solution, we propose a continuous and differentiable function to approximate the 1-bit signal, such that the problem with discrete 1-bit constraint is recast to an unconstrained optimization problem with a penalty term, which can be effectively solved via the limited-memory Broyden, Fletcher, Goldfarb, and Shanno (L-BFGS) approach. Moreover, it is found that a closed-form solution can be obtained when equal weights are applied. In addition, low-complexity schemes are developed based on the fast Fourier transform (FFT). The numerical simulations are conducted to demonstrate the effectiveness and superiority of the proposed method.
A VS30 Map for New Zealand Based on Geologic and Terrain Proxy Variables and Field Measurements

A time-averaged 30-m-depth shear wave velocity (VS30) map is developed for New Zealand as a weighted combination of a geology-based and a terrain-based model. A Bayesian updating process allows local VS30 measurements to control model estimates where data exist and uses model estimates developed for other parts of the world where local data are sparse or nonexistent. Geostatistical interpolation is performed on the geology-based and terrain-based models using local VS30 measurements to constrain the model in the vicinity of data. Conventional regression kriging is compared with a flexible multivariate normal (MVN) approach that allows for arbitrary assumptions regarding measurement uncertainty at each data location. A modification to the covariance structure in the MVN application allows for more realistic estimates by reducing undesirable extrapolation across geologic boundaries. The results of kriging and MVN approaches are compared. The geology-based and terrain-based MVN models are combined to produce a final model suitable for engineering applications. The 100-m resolution map outputs are publicly available.
Built Environment Factors Affecting Bike Sharing Ridership: Data-Driven Approach for Multiple Cities

Identification of factors influencing ridership is necessary for policy-making, as well as, when examining transferability and aspects of performance and reliability. In this work, a data-driven method is formulated to correlate arrivals and departures of station-based bike sharing systems with built environment factors in multiple cities. Ridership data from stations of multiple cities are pooled in one data set regardless of their geographic boundaries. The method bundles the collection, analysis, and processing of data, as well as, the model’s estimation using statistical and machine learning techniques. The method was applied on a national level in six cities in Germany, and also on an international level in three cities in Europe and North America. The results suggest that the model’s performance did not depend on clustering cities by size but by the relative daily distribution of the rentals. Selected statistically significant factors were identified to vary temporally (e.g., nightclubs were significant during the night). The most influencing variables were related to the city population, distance to city center, leisure-related establishments, and transport-related infrastructure. This data-driven method can help as a support decision-making tool to implement or expand bike sharing systems.
Ultra-Low Complex Blind I/Q-Imbalance Compensation

Direct-conversion transceivers are the predominating architecture in current mobile communication systems. Despite many advantages, this topology suffers from unavoidable mismatches in the analog part, which causes imbalance between the in-phase and quadrature (I/Q) component. In this paper, we present a novel fully digital, blind I/Q imbalance compensation algorithm that features extremely low computational complexity and high compensation performance for a wide range of input signal types. Different to many state-of-the-art compensation schemes, the approach is not based on a gradient descent optimization and does not require any global feedback. This simplifies the implementation at high data rates and reduces the configuration effort to a minimum. For comparison, we examine an existing method of moment-based estimator with similar properties, for which we also provide the detailed insights beyond available literature. For both algorithms, we provide a rigorous mathematical analysis, which is supported by simulations with a focus on various long-term evolution (LTE) signal types. In addition, hardware architectures, including field-programmable gate array (FPGA) verification, are presented for both algorithms.
Simulation of the Knee Joint Motion by Stewart Platform

iii ÖZ . v DEDICATION . vii ACKNOWLEDGMENT . viii LIST OF TABLES . xi LIST OF FIGURES . xii LIST OF ABBREVIATIONS . xiii LIST OF SYMBOLS . xiv