Miracle-dz/UniFAR-FTUs huggingface dataset:
Equivalent-Circuit Model for Quartz Resonators Effects of Finite Element Analysis, Acceleration, and Mass Loading

In radar equipments and communication systems, quartz resonators are key components. So as to enhance the resonator performances, the development of accurate modelings taking into account the environment interaction (temperature, acceleration, magnetism, …) is one of the major economic and strategic stakes. The main idea is to produce a realistic modeling. In literature, a lot of modelings are based on finite element analysis. But, for industrial applications, it is essential to link these accurate modelings to electric simulation softwares, such as Spice. Moreover, it is necessary to develop a simple computation method in order to answer the industrial time constraints. The idea is to use a Butterworth-Van Dyke (BVD) model based on an electrical equivalent circuit with, as input data, the studied natural frequency and the antiresonance frequency of an accurate finite element modeling. For the numerical example, a SC-cut (Stress-Compensated cut) quartz resonator is studied in this article for its fundamental thickness-shear resonance, the third and the fifth overtone. The influence of the model mesh quality, the electrode mass-loading, and the acceleration sensitivity on the motional parameters are analyzed. First, the choice of the finite element number along the thickness axis is crucial for the computation accuracy of the motional parameters. Then, the more the electrode material has a high density, the more the mass loading has a strong influence of the motional parameter values. Finally, the motional parameters are not really influenced by the acceleration field.
Predictive control to modelling motorcycle rider steering

The response of a motorcycle is heavily dependent on the rider's control actions, and consequently a means of replicating the rider's behaviour provides an important extension to motorcycle dynamics. The primary objective here is to develop effective path-following simulations and to understand how riders control motorcycles. Model predictive control theory is applied to the tracking of roadway by a motorcycle, using a non-linear motorcycle model operating in free control by steering torque input. A path-following controller with road preview is designed by minimising tracking errors and control effort. Tight controls with high weightings on performance and loose controls with high weightings on control power are defined. Using a model predictive control approach, an extensive parameter study is conducted to evaluate its suitability. The controller model is simulated over a standard single lane-change manoeuvre. The results show the expected pattern for preview control and broadly compare with conclusions drawn from the optimal linear quadratic methods in previous studies. Furthermore, the approach is believed to accurately reflect the control actions taken by a human motorcycle rider.
TQWT and WDGA: innovative methods for ground roll attenuation

The existence of noise in seismic data has an undesirable effect on seismic interpretations. An important type of coherent noise is ground roll, in which time and frequency overlap with useful seismic signals. The tunable Q-factor wavelet transform is a new discrete wavelet transform method and is considered as a new tool for ground roll attenuation. The simple tunable Q-factor wavelet transform by using a single wavelet with explicit oscillatory behavior is utilized for each trace. The enhanced tunable Q-factor wavelet transform (for seismic signals), which benefits from several mother wavelets with distinct Q-factors (for each part of a signal), is presented here and it is shown that it can adjust reliably to the natural non-stationary behavior of a seismic signal in time and space. Random noise has an undesirable effect on Q-factor ranges, with extreme consequences. Wavelet domain ground roll analysis is used as a substitute approach to thresholding for ground roll attenuation. The simple tunable Q-factor wavelet transform and the enhanced tunable Q-factor wavelet transform are compared with each other and with the f-k method by using synthetic and real data samples.
Micro-Electro-Mechanical System/Field-Effect-Transistor Hybrid Switch for Energy Scavenging System

An innovative micro-electro-mechanical system/metal–oxide–semiconductor field-effect-transistor (MEMS/MOSFET) hybrid switch is presented. The main switch of the hybrid device is a MOSFET switch whose gate voltage is supplied through a MEMS switch. The electrostatic operation mechanism and inherent hysteresis characteristics of MEMS switch combined with the characteristics of MOSFET provides a high current handling capability, a low power consumption, self-referencing, a high noise immunity, and an ease of control and all of these advantages are experimentally demonstrated in practical circuits. This hybrid switch can be employed in energy scavenging system and in other electronic devices in order to save standby energy.
Post-earthquake modelling of transportation networks

Transportation networks are critical civil infrastructures susceptible to natural hazards such as earthquakes. It is essential to understand and model the travel demand in emergency situation when considering measures to secure traffic function immediately after the earthquake and to restore the performance of transportation networks. Post-earthquake travel demand is complicated, and the changes of traffic pattern after the event are often coupled with the physical damage of transportation infrastructures. This study develops a scenario-based methodology to model the performance of post-earthquake transportation systems by extending the combined trip distribution and assignment model. Several general assumptions are made on post-earthquake travel behaviour and emergency traffic management measures. The proposed methodology is demonstrated with the Sioux-Falls road network and results are presented. The findings suggest that such scenario-based integrated methodology can capture the post-earthquake travel characteristics and is capable to provide more reasonable results than conventional transportation modelling approaches. The methodology can be used to model the emergency demand and post-earthquake performance of transportation systems. It is helpful to aid traffic planners and emergency managers in evaluating their contingency traffic plans and making decisions in emergency management.
Cavity-backed archimedean spiral antenna with strip absorber

The characteristics of an Archimedean spiral (ARSP) antenna backed by an extremely shallow cavity (0.07 wavelength at the lower operating design frequency of 3 GHz) are analysed. It is revealed that the presence of the cavity causes noticeable variation in the antenna characteristics at low frequencies. To restore the wideband characteristics inherent to the ARSP, a ring-shaped strip absorber (R-ABS) is placed under the spiral arms. It is found that the wideband antenna characteristics are successfully restored with the use of the R-ABS. Subsequently, the R-ABS is divided into two arc-shaped strip absorbers and the volume of each is reduced by decreasing the arc-angle ARC from 180deg (corresponding to an R-ABS) to 0deg (corresponding to a cavity without an absorber). It is shown that when the arc-angle is chosen to be greater than deg ARC =90=, the antenna characteristics obtained for = ARC =180= are reproduced. Theoretical results are confirmed using results from experimental work.
ANÁLISE SOCIOMÉTRICA DE INTERAÇÕES ENTRE PROFESSORES DE CIÊNCIAS EM UM PROGRAMA ON-LINE DE FORMAÇÃO CONTINUADA

The sociometric analysis has been developed since the beginning of the XX century and it has been overgrown with the came of digital technologies. In this paper, through the sociometric analysis, we sought to promote quantitative analysis by network indicators, in order to find patterns of interaction between twenty-six tutors of a discussion forum set up in an online course of Science Education offered to in-service teachers. To collect the data, one has been used the softwares SNAPP 1.5, NetDraw and UCINET 6. The softwares enable quantitative and qualitative analysis of social relations in virtual learning environments. We concluded that the tutors analyzed tend to have a greater centering pattern than a random pattern.
EROSION OF FRACTURED MATERIALS

The natural fracture patterns that often exist in soil and rock materials are believed to have a major influence on how these materials erode. Material that normally would not be expected to erode when exposed to flowing water can fail along existing fracture planes. Conventional strength testing does not necessarily account for these potential failure surfaces. The objective of this study was to investigate the dominant parameters that cause failure of a fractured block matrix. A study was conducted by placing a matrix of blocks downstream of an overfall. The discharge over the overfall was increased until the block matrix failed due to the forces transmitted by the impinging flow. The block size, block orientation, and overfall height were varied systematically over a range of flow rates. Test results are presented, and the dominant failure mechanisms are described. The failure discharge was observed to decrease as the overfall height increased. This result was expected because the larger drops allow the flow to impact the surface with more energy. The failure discharge was also observed to increase if the block was placed with its long axis oriented vertically. This orientation distributed the block weight over a smaller area, thus requiring an increased pressure to dislodge the block. The repeatability of these fractured material tests was also examined, as was the block layer thickness. In addition to the hydraulic erosion of fractured materials, preliminary results on the measurement of pressures below a block matrix are discussed. This article provides fundamental research information concerning scour hole development and headcut erosion in fractured materials.
Advances in high-frequency power conversion by delta-sigma modulation

The delta-sigma technique has been recently proposed for power processing and the idea is particularly attractive in audio power amplifying area. This paper aims to apply this technique to high-frequency power conversion. The well known switching power supply topologies have been revised for this purpose. A laboratory prototype of a suitable power converter has been realized and tested. Analysis, experimental results and evaluation on efficiency and power range are presented.
Automated Valuation Models: an international perspective

This paper describes two research projects: the first carried out during Q2 2007 for the Council of Mortgage Lenders (CML) and MacDonald Dettwiler and Associates (Downie & Robson, 2007). The second is a questionnaire survey of RICS Residential Faculty members, carried out Q2 2008, as part of an ongoing study funded by the RICS Education Trust and the RICS Residential Faculty, investigating how AVMs can integrate with valuation services to meet the needs of borrowers, lenders and RICS members. Both projects were undertaken by the School of the Built Environment at Northumbria University. The former predates the credit crunch and the latter coincided with it. The paper will first outline the main findings of the CML report, then those of the valuer questionnaire and finally draw conclusions about issues for consideration by professional and industry bodies.
Simulation and Experimental Study of the Direction Control Based on the Torque Compensation of a Snake Robot

Because the direction goals of the snake robot are different in applications, e.g. the target point and target path, the direction control of a snake robot is a challenging problem. We have proposed a control method, which is called passive creeping based on the energy balance. In this paper, the direction of the snake robot which is controlled by the passive creeping control method is discussed. A new direction control method which is based on the torque compensation is proposed. The direction control method set a universal direction goal for all the applications. The torque of the head joint which leads the locomotion direction is adjusted by the torque compensation. The compensated torque decreases the angle between the direction of the body axis and the expected direction by the exponential decay function. In simulation, the trajectory and the angle express the process of direction adjustment. The error analysis proves the validity and adaptability of the proposed direction control. Also the validity of the proposed method is proved by the experiment which is based on the virtual/physical mixed experimental system.
Period Stabilization of Timing Multi–vibrators†

ABSTRACT The problems of instability of periods and pulse lengths of transistor timing multi-vibrators are reviewed. A modified monostable multi-vibrator with improved charaecteristics in freedom from jitter and better temperature stability is described. This uses germanium alloy transistors with a complementary type silicon transistor in grounded base configuration as a constant current source through which the timing capacitor discharges. In addition a silicon diode effectively isolates the timing network during timing interval. A feature of the circuit is the linear voltage waveform obtainable and its useful applications with suitable modifications are as a linear delay circuit or as an analogue-to-digital converter of high accuracy.
Values, Materialism and Life Satisfaction: A Study of Cultural Influence and Gender Differences in China

The number of middle-class consumers has grown significantly following China’s economic development. As well as increasing their consumption, the Chinese have also become increasingly materialistic, raising the question of whether increasing material acquisition and possession have led to greater life satisfaction. This paper, using a convenience sample of 600 Chinese, examines the influence of cultural dimensions (uncertainty avoidance, long-term orientation, power distance, collectivism, masculinity) on materialism and life satisfaction. A comparison of gender difference was conducted to understand the gender role played in forming individuals’ values, attitudes, and social behavior. The influence of culture and gender roles was partially confirmed.
Low-voltage Low-power Folded Mixer Using Current-reuse Technical for IEEE 802.11b Wireless Application

Abstract In this paper, a new CMOS low-voltage, low-power folded up-conversion mixer using current-reuse Technique based on Chartered 0.18 ¼m RF CMOS technology for 2.4 GHz IEEE 802.11 b WLAN receiver applications is presented. Because of the current-reuse Technique and the folded structure used in the mixer, the mixer can realize self-biasing, and the bias voltages at the local oscillator (LO) and the intermediate frequency (IF) terminals are not necessary. Moreover, the post-layout simulation results demonstrate that the proposed mixer can provide about 9.5 dB conversion gain with 1 V supply voltage, while the power consumption is only 258 ¼W, and the 1 dB compression point and input-referred third-order intercept point (IIP3) of the mixer are 3.2 dBm and 3.8 dBm, respectively. The chip area including test pads is only 0.75 × 0.80 mm2. Comparing with the previously reported mixers, the proposed mixer has the advantages of lower supply voltage, lower power consumption, higher linearity, and smaller chip area than most of the other reported works.
Four-terminal-pair impedances and scattering parameters

The calibration of modern automatic RLC bridges requires a set of impedance standards. Each standard needs in turn a calibration, i.e. the knowledge of its four-terminal-pair impedance Z4TP at frequencies up to 10–100 MHz—frequencies beyond the capabilities of standard metrological setups for impedance traceability (transformer bridges). It is possible to think of an impedance standard as a multiport linear radiofrequency network; the properties of the network can be mathematically related to its Z4TP. In the literature, such a connection is made using the relation between the impedance matrix Zij and Z4TP, and with careful identification of an ad hoc lumped-parameter electrical model of the standard. A vector network analyser is employed to measure diagonal elements of Zij directly; non-diagonal elements are measured in an indirect way. Here we derive a new relation between the scattering parameter matrix sij and Z4TP of the impedance standard. All sij elements can be directly measured with a network analyser: we measure scattering parameter spectra of a set of commercial gas-dielectric capacitors. Computed Z4TP spectra are compatible with those obtained with the Zij technique, but the new method proves much more sensitive, permitting estimates of the frequency behaviour of an impedance standard even when electrical modelling is inconvenient or impossible.
Advances in PV semiconductor materials and technology

It is now accepted that photovoltaics is the most promising of the renewable energy sources for electric power generation. Photovoltaic's ability to provide reliable, high grade energy over an extended lifetime is now well proven in both space and terrestrial applications. Widespread adoption of this clean, silent power source, however, still awaits the achievement of a number of outstanding technical and economic objectives. Extensive research into photovoltaic technology over the last two decades has done enough to conclude that all these goals can be met. The present challenge is to apply these results industrially and commercially so as to make the dream and reality. Photovoltaics can only provide an efficient service to its users if it provides a transparent and trouble free source of electricity. This involves the application of photovoltaic devices in well integrated systems which also include appropriate mechanical and electrical interfaces. The author focuses on one part of the system-the photovoltaic generator itself. This paper reviews the status of international developments and the contributions which they can make in achieving this objective. (4 pages)
Liquid properties in the Fe-FeS system under moderate pressure: Tool box to model small planetary cores

Abstract Physical properties of liquid Fe-S alloys (from 10 to 50 at%S) under high pressure were investigated by in situ X‑ray diffraction (up to 5 GPa and 1900 K) and by ab initio calculations. The local structure of Fe-S liquid alloys clearly shows how S modifies the local arrangement of the Fe atoms. Density has been extracted from the diffuse scattering by minimization of the oscillation in the short distance of the radial distribution function g(r). Two different formalisms for the P-V-T-X equation of state are presented to model density and sound velocity as a function of pressure, temperature, and sulfur content. Based on these results, Moon’s core composition is discussed. This coherent data set will serve as a thermodynamically consistent ground for modeling the core of small telluric planets and large icy satellites.
Synchronized microscanner array for large aperture receiver optics of LIDAR systems

Traditional laser scanners for 3D distance measurement involve expensive, heavy, (potentially) slow rotating mirrors for light deflection of the scanning TOF (time of flight) distance measurement, not suitable for compact, robust and highly portable LIDAR system. On the other hand MEMS scanners are limited to small apertures not suitable for a precise TOF measurement. To overcome this problem Fraunhofer IPMS presents a large aperture 1D-MEMS scanner array especially designed for LIDAR applications. It is composed of 2 × 7 silicon mirror elements each having an identical design with comparatively large aperture of 2.51 × 9.51mm2 and ±30° optical scan range. All mirrors are driven electrostatically resonant with identical frequency close to design frequency of 250 Hz. By driving control all single scanner elements are synchronized to identical phase and amplitude in respect to a master scanner. This results in a large effective scanner aperture of 334 mm2 for the receiver optics and a filling factor of 80 %. To guarantee the synchronized operation the paper discusses in detail the scanner design to enable a sufficiently large frequency bandwidth of all scanner elements to the compensate frequency tolerances caused by fabrication and packaging. In comparison to LIDAR systems with conventional scanner components, the large aperture 1D-MEMS scanner array enables 3D-LIDAR systems to become significantly smaller, more robust and (potentially) less expensive, also higher scan rates can be realized without additional efforts (e.g. no air bearings are needed).
Uncooled low-voltage AlGaAsSb/InGaAsSb/GaSb avalanche photodetectors

Low-voltage AlGaAsSb/InGaAsSb/GaSb separate absorption and multiplication avalanche photodiodes (SAM-APD), as well as InGaAsSb/GaSb APDs with an AlGaAsSb passivating layer, are fabricated using liquid phase epitaxy. Formation of the p–n junction is performed either epitaxially or through diffusion of Zn from the vapour phase. Responsivity as high as 43 A/W at wavelength of 2100 nm is achieved at room temperature in AlGaAsSb/InGaAsSb/GaSb SAM-APDs reverse biased at 6.7 V. Relatively high responsivity (8.9 A/W at 2000 nm) was also measured in an InGaAsSb/GaSb APD reverse biased at 7.5 V.
Ian Read Gibbons. 30 October 1931—30 January 2018

Ian Read Gibbons is best known for discovering dynein, a molecular motor that powers the motion of cilia and flagella, is involved in assembling the mitotic spindle and moves chromosomes as well as other cargoes inside cells. Gibbons devoted his career in the lab of more than 50 years to understanding the mechanism of how dynein works in driving motility. In doing so, he built a life-long reputation as a creative, collaborative and tenacious researcher with an unusual gift for crafting innovative solutions to tricky experimental problems. His experimental methods spanned electron as well as light microscopy, biochemistry, molecular biology, crystallography and molecular modelling. He perceived the right set of experimental moves that would allow him to dissect and observe the physical underpinnings of minute biological processes such as the delicate movements of dynein. Gibbons traced his success to the ability to envision how pieces of a scientific puzzle might fit together to make a coherent story: ‘My own approach to research has always emphasized intuition over logic. Perhaps for that reason, I get attracted to questions with aesthetic appeal. ’ Even though dynein holds much promise for helping to engineer ways to fight disease, Gibbons' focus was always on the intrinsic grace of understanding nature's workings. Gibbons’ marriage to his biochemist wife Barbara played a particularly vital role in his life. Barbara and Ian worked frequently together as she built her own scientific career through their partnership in the study of dynein. Ian's many scientific accomplishments as well as his dedication to his friends and family represent enduring gifts to us all.
The Cuckoo Search Algorithm Based on Dynamic Grouping to Adjust Flight Scale

The cuckoo search (CS) algorithm is a very efficient swarm optimization algorithm. Based on CS, a cuckoo search algorithm based on dynamic grouping to adjust flight scale (DGCS) is proposed: All cuckoos are divided into three groups according to the fitness of the individual and the average fitness of the population, then different flight scale is adopted dynamically for each group. Simulation experiments show that the DGCS can quickly converge to the global optimum solution, and has better optimization performance.