Coupled Device Research Articles

РАСПРЕДЕЛЕНИЕ КРУТЯЩИХ МОМЕНТОВ ПО КОЛЕСАМ ТРАКТОРА

The regularities of the distribution of torques on axles and tractor wheels have been studied. An energy-saturated universal tractor of class 2 integrated circuit LTZ-155 with all driving and steered twin wheels of the same size with tires of size 9.5-42 was chosen as the object of research. The studies were carried out under the following layout options and driving conditions: 1) rectilinear movement of a separate tractor - idling; 2) execution of the technological process during operation of the machine-tractor unit in row spacing of row crops - cultivation; 3) rectilinear movement of a machinetractor unit with guns in the transport position - idling. It was found that the total values of torques on tractor wheels under relatively constant driving conditions for all experimental races with an increase in translational speed of movement slightly, by about 5... 18%, increase due to an increase in the frequency of the dynamic impact of the microprofile from the side of the bearing surface on the wheels and fluctuations in the traction load. At the same time, the mean square deviation of the wheel moments does not exceed 18... 25% of their average value, which is constant for a stationary ergodic process. With the considered variants of operation of the machine-tractor unit, the redistribution of torques, both on the axles and on the wheels of each axle, even if we assume that a constant total torque is supplied to the driving wheels, is very complex and dynamic, due to the inaccuracy of landings due to the tolerances of the coupling in the coupling device between the tractor and the cultivator from- due to the inability to comply with the alignment of the covered and encompassing connecting elements of the connecting triangles, this leads to an asymmetry of the normal weight load of the wheels from the mounted guns and the corresponding non-proportional distribution of traction forces on the wheels.

Approach of recognition and precision location for the beacon in satellite optical communications

Satellite optical communications have high communication speed and good confidentiality, which can establish high-speed and large-capacity communication links between satellites and the ground or other satellites. The requirements for the PAT (pointing, acquisition and tracking) system of satellite optical communication terminals are very high. In satellite optical communications, the biggest influence on the beacon’s recognition and tracking is the background light on CCD (Charge Coupled Device). Therefore, denoising work is required during the recognition or tracking process. This paper uses corner detection method to extract the beacon frame by frame. Mark the spot, and use the optical flow method to calculate the optical flow displacement based on the two consecutive frames. In addition, calculation accuracy of the beacon’s centroid is compared with that of the tradition method. The feasibility is verified by simulation experiment, the tracking process is completed, and the noise can be precisely eliminated.

A Systematic Review of the Transthoracic Impedance during Cardiac Defibrillation.

For cardiac defibrillator testing and design purposes, the range and limits of the human TTI is of high interest. Potential influencing factors regarding the electronic configurations, the electrode/tissue interface and patient characteristics were identified and analyzed. A literature survey based on 71 selected articles was used to review and assess human TTI and the influencing factors found. The human TTI extended from 12 to 212 in the literature selected. Excluding outliers and pediatric measurements, the mean TTI recordings ranged from 51 to 112 with an average TTI of 76.7 under normal distribution. The wide range of human impedance can be attributed to 12 different influencing factors, including shock waveforms and protocols, coupling devices, electrode size and pressure, electrode position, patient age, gender, body dimensions, respiration and lung volume, blood hemoglobin saturation and different pathologies. The coupling device, electrode size and electrode pressure have the greatest influence on TTI.

Measuring Velocity, Attenuation, and Reflection in Surface Acoustic Wave Cavities Through Acoustic Fabry-Pérot Spectra.

Surface acoustic wave (SAW) cavities have been widely applied as electronic bandpass filters, sensors, microfluidic tweezers, and, in recent years, as devices for coupling with quantum systems. Here we propose a novel method of analyzing acoustic Fabry-Pérot spectra, by analogy with optical cavities, to determine the free surface velocity and attenuation of SAW waves, as well as the reflection of interdigital transducers (IDTs), all of which are crucial design parameters. In our experiment, two-port SAW resonators, consisting of two IDTs laterally separated by a free surface cavity length, are used to generate SAWs on 128° Y-X lithium niobate that are trapped between the two IDTs which also act as Bragg reflectors. Resonant cavity peaks can be observed through the electrical S11 (reflection) spectrum measured on one IDT. The free spectral range and linewidths of cavity peaks are then measured to obtain the free surface SAW velocity, SAW propagation attenuation coefficient, and IDT reflection phase and amplitude. Our method of analyzing Fabry-Pérot spectra provides an intuitive approach for determining key characteristics of SAW waves and cavities.

Characteristic studies on positive and negative streamers of double-sided pulsed surface dielectric barrier discharge

The mechanisms of streamer generation and propagation in double-sided pulsed surface dielectric barrier discharge (SDBD) on both sides have been analyzed and investigated by experiment and numerical simulation. The fully exposed asymmetric SDBD has two discharge processes located on the high voltage electrode (HVE) side and the ground electrode (GE) side. Discharge images of the HVE side and GE side are taken by a digital camera under continuous pulse and ICCD (Intensified Charge Coupled Device) is utilized to diagnose the generation and propagation of streamers in single pulse discharge. In order to understand the physical mechanisms of streamer evolution more deeply, we establish a 2D simulation model and analyze it from the aspects of electron density, ion density, reduced electric field and electron impact ionization source term. The results show that the primary and secondary discharges on the HVE side and the GE side of the double-sided SDBD are composed of positive streamer and negative streamer, respectively. On the HVE side, the accumulation of positive charges on the dielectric surface causes the direction of the electric field to reverse, which is the principal factor for the polarity reversal of the streamer. On the GE side, both the negative charges accumulated on the dielectric surface and the falling voltage are the key factors for the streamer polarity switch.

Experimental assessment of noise robustness of the forward-additive, symmetric-additive and the inverse-compositional Gauss-Newton algorithm in digital image correlation

Digital Image Correlation (DIC) is a well-known optical experimental method based on the assumption that pixel intensity does not change with motion. This assumption is never exactly satisfied because various sources of noise exist (read-, shot-, dark-noise of the Charge Coupled Device (CCD), thermal dilatation of lens, non-constant illumination,...); moreover, to accurately track displacements, pixel intensity has to be interpolated at non-integer locations, thus introducing both phase and intensity errors due to the use of theoretically incorrect interpolating kernels.DIC can be implemented using various formulations, the most used being the Forward-Additive Gauss-Newton (FA-GN) and the Inverse-Compositional Gauss-Newton formulation (IC-GN). Even though both formulations give the same results at the first order, their speed, converging characteristics, and noise robustness differ considerably in particular with regard to the noise bias. Indeed, Shao et al. [1], using a theoretical analysis of a mono-dimensional signal and a numerical simulation on FFT-shifted images, recently showed that the latter formulation is not affected by noise bias, providing the correct differential operator is used.In this work, a fully experimental assessment of the noise-bias sensitivity of both algorithms is performed, confirming the theoretical findings and the numerical simulations available in the literature.

Coupling characteristics of laterally coupled gratings with slots

Laterally-coupled ridge-waveguide distributed feedback lasers fabricated without epitaxial regrowth steps have the advantages of process simplification and low cost. We present a laterally coupled grating with slots. The slots etched between the ridge and grating area are designed to suppress the lateral diffusion of carriers and to reduce the influence of the aspect-ratio-dependent-etching effect on the grating morphology in the etching process. Moreover, the grating height in this structure can be decreased to lower the aspect ratio significantly, which is advantageous over the conventional laterally coupled ridge waveguide gratings. The effects of five main structural parameters on the coupling characteristics of gratings are studied by MODE Solutions. It is found that varying the lateral width of the grating can be used as an effective way to tune the coupling strength; narrow slots (100 nm and 300 nm) and wide ridge (2 μm–4 μm) promote the stability of grating coupling coefficient and device performance. It is important to note that the grating bottom should be fabricated precisely. The comparative study of carrier distribution and mode field distribution shows that the introduction of narrow slots can strengthen the competitive advantage and stability of the fundamental mode.

Conformity assessment model for mechanical coupling devices and anchors for reinforcing steel for use in concrete structure

The use of mechanical coupling devices and anchors for reinforcing steel for use in concrete structures can simplify the design and construction of reinforced concrete and reduce the amount of reinforcement required. Technical Approvals of these products by suitably qualified organisations are acceptable under Building Regulations and by major specifiers as the appropriate way of assessing non-standard or new and innovative products. Specifiers, manufacturers, traders, and customers increasingly demand certainty in the quality management of mechanical coupling devices and anchors entering the supply chain. The supply chain is extremely complex. The weak traceability systems and pressure on the supply chain to reduce cost have created the environment where risks increase. This unique and comprehensive model describes the technical and assessment requirements for the conformity of mechanical coupling devices and anchors. It covers all stages in the supply chain from the production, assembly, product performance and evaluation of mechanical properties including tensile strength, ductility, permanent elongation (slip), cyclic loading performance and fatigue performance. The essential elements of the quality management system combined with additional requirements on process control, product testing and robust installation methodology are essential and agreed by all relevant sectors of industry.

Coupling Device by Self-Written Waveguide Technology for Optical Interconnection between Silicon Photonics Chip and Fiber

Coupling Device by Self-Written Waveguide Technology for Optical Interconnection between Silicon Photonics Chip and Fiber

Study of stagnation layer of laterally colliding laser produced aluminium plasmas

When two dense laser produced plasmas collide, a layer of plasma stagnates at the collision front exhibiting special properties, is called stagnation layer. The characteristics of stagnation layer formed due to the collision of two laser produced aluminium plasmas were studied using spectroscopic and the fast imaging techniques. Time gated Intensified Charge Coupled Device (ICCD) imaging was used to study the temporal evolution of stagnation region and time resolved spectroscopy was used to obtain information about the distribution of neutral as well as the ionic species in collision process of laterally colliding aluminum plasmas. Electron density and temperature of the stagnation layer were also calculated from the emission spectra. The overall experiment results clearly depict the peculiar properties of stagnation layer which is more advantageous than the conventional laser produced plasma.

A miniature kinematic coupling device for mouse head fixation

• Development of a kinematic clamp for mice for precise repositioning in chronic studies. • Headplate and clamp provide stability for cellular resolution imaging during behavior. • Ruby contact features enable submicron registration repeatability.

Power Line Communication Over Flexible Cables for Elevator Cabins

Narrowband power line communication has become a major focus of research with its applicability extending to residential facilities. This article examines data transmission over flexible AC power line cables stretching from the elevator control panel to the cabin. In previous studies, there has been no significant attempt to characterize the Power Line Communication (PLC) channel and noise of an elevator system. In this article, a vector network analyzer and mixed domain oscilloscope along with coupling devices are used to conduct power line channel noise and response measurements for an elevator system. The acquisition of channel transfer functions corresponding to both idle and moving states of the elevator is carried out for the 9 kHz–500 kHz frequency range. A mathematical model is provided for the average frequency response of the PLC channel. The main source of noise is the inverter that supplies power to the motor. The channel exhibits notable variations for frequencies less than 281 kHz while staying relatively consistent for the 281 kHz to 500 kHz frequency range as the elevator changes from idle to moving state. Reed Solomon and convolutional codes along with interleaving to spread erroneous bits are utilized in this work to simulate an orthogonal frequency division multiplexing transceiver. By systematically selecting subcarrier frequencies that do not overlap with the harmonic noise components, simulation results have demonstrated reliable data recovery for signal-to-noise ratio greater than 4 dB.

A Novel Synchronous Type Variable Speed Wind Turbine and Its Control Strategy Study

Compared with traditional power plants, current main stream wind turbines vary in grid connection interfaces, resulting in deficiencies like weak grid voltage and frequency support capability. In order to solve the problem, a synchronous type variable speed wind turbine is proposed in this paper. The wind turbine has the advantages such as the intrinsic properties of maintaining grid voltage and frequency, no harmonic pollution on grid, black start capability. In the wind turbine drive train, an electrically excited synchronous generator is directly coupled to the grid. A power self‐balance type electromagnetic coupling device is used to connect the synchronous generator rotor shaft and a gearbox high speed shaft. The device is composed of a permanent magnet synchronous generator (PMSG), a back‐to‐back converter and an electromagnetic coupler. The converter with small capacity, supplied by the PMSG which is coaxial with the gearbox high speed shaft, is used to apply the electromagnetic torque of the electromagnetic coupler. The matching relationship between the electromagnetic torque and the turbine mechanical torque, and the power flow in the drive train in different wind speeds are analyzed. Control strategies are proposed for the wind turbine normal operation including start, stop, maximum wind power capture, and low voltage ride through (LVRT). Compared with the main stream wind turbines, blade and tower loads can be improved greatly during LVRT. A 2 MW wind turbine model is built in Matlab/Simulink to verify the control strategies proposed and the wind turbine excellent LVRT performance. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Toward systematic architectural design of near-term trapped ion quantum computers

Trapped ions (TIs) are a leading candidate for building Noisy Intermediate-Scale Quantum (NISQ) hardware. TI qubits have fundamental advantages over other technologies, featuring high qubit quality, coherence time, and qubit connectivity. However, current TI systems are small in size and typically use a single trap architecture, which has fundamental scalability limitations. To progress toward the next major milestone of 50--100 qubit TI devices, a modular architecture termed the Quantum Charge Coupled Device (QCCD) has been proposed. In a QCCD-based TI device, small traps are connected through ion shuttling. While the basic hardware components for such devices have been demonstrated, building a 50--100 qubit system is challenging because of a wide range of design possibilities for trap sizing, communication topology, and gate implementations and the need to match diverse application resource requirements. Toward realizing QCCD-based TI systems with 50--100 qubits, we perform an extensive application-driven architectural study evaluating the key design choices of trap sizing, communication topology, and operation implementation methods. To enable our study, we built a design toolflow, which takes a QCCD architecture's parameters as input, along with a set of applications and realistic hardware performance models. Our toolflow maps the applications onto the target device and simulates their execution to compute metrics such as application run time, reliability, and device noise rates. Using six applications and several hardware design points, we show that trap sizing and communication topology choices can impact application reliability by up to three orders of magnitude. Microarchitectural gate implementation choices influence reliability by another order of magnitude. From these studies, we provide concrete recommendations to tune these choices to achieve highly reliable and performant application executions. With industry and academic efforts underway to build TI devices with 50-100 qubits, our insights have the potential to influence QC hardware in the near future and accelerate the progress toward practical QC systems.

Ultrafast modulation of valley dynamics in multiple WS2\u2009\u2212\u2009Ag gratings strong coupling system

Strong light-matter interactions in two-dimensional transition metal dichalcogenides (TMDCs) with robust spin-valley degrees of freedom open up the prospect of valleytronic devices. A thorough understanding on the dynamics of the valley polarizations in the strong coupling regime is urgently required. Here, multiple polarized TMDCs-SPPs hybrid systems were constructed by combining monolayer WS2 flakes to linear, circular, and spiral Ag gratings, resulting in linear and circular polarized modulation on the coherent hybrid states, respectively. Particularly, valley polaritons can be tailored asymmetrically by chiral strong coupling regime. Furthermore, the dynamics of the polarized polaritons were directly analyzed by transient absorption (TA) measurement. Both of the linear and circular polarization difference in the TA spectra can be retained for a remarkable long time, leading to a polarized PL even at room temperature. More importantly, in the chiral strong coupled WS2-spiral Ag grating devices, the mechanism of the asymmetrical valley-polarized PL (p σ+ = 14.9% and p σ- = 10.8%) is proved by the opposite valley polarization dynamics in the circularly polarized TA spectra. The multiple polarization modulation in monolayer TMDCs-SPPs strong coupling devices could provide a viable route toward multiple polarization polaritonic devices.

Imaging inspired characterization of single photons carrying orbital angular momentum

We report on an imaging-inspired measurement of orbital angular momentum (OAM) using only a simple tilted lens and an intensified charged coupled device camera, allowing us to monitor the propagation of OAM structured photons over distance, which is crucial for free-space quantum communication networks. We demonstrate the measurement of OAM orders as high as ls = 14 in a heralded single-photon source and show, for the first time, the imaged self-interference of photons carrying OAM in a modified Mach–Zehnder interferometer. The described methods reveal both the charge and order of a photon's OAM and provide a proof of concept for the interference of a single OAM photon with itself. Using these tools, we are able to study the propagation characteristics of OAM photons over a distance, which is important for estimating transport in free-space quantum links. By translating these classical tools into the quantum domain, we offer a robust and direct approach for the complete characterization of a twisted single-photon source, an important building block of a quantum network.

ПОВЫШЕНИЕ ЭФФЕКТИВНОСТИ ЛЕСОВОЗНОГО АВТОПОЕЗДА ПУТЕМ ИСПОЛЬЗОВАНИЯ РЕКУПЕРАТИВНОГО ПНЕВМО-ГИДРАВЛИЧЕСКОГО СЦЕПНОГО УСТРОЙСТВА

The necessity of using timber trucks with trailers in order to increase the productivity of hauling timber has been substantiated. The advantages of using timber trucks with trailers over single timber trucks are described. The analysis of scientific works of foreign authors in the field of increasing the efficiency of timber trucks with trailers is carried out. An assessment was made of the operation of timber trucks with trailers in the existing conditions for the transportation of timber in the Russian Federation. The negative factors limiting the efficiency of timber-carrying road trains are revealed. The most significant factor, which can lead to dangerous consequences, is highlighted, which consists in the emergence of critically large forces in the coupling device of a timber road train during sudden braking. Changes in the braking forces of the bridges of a logging vehicle with a trailer during sharp braking, as well as three possible cases of interaction when braking a logging vehicle with a trailer, are considered. A promising design of a recuperative pneumohydraulic coupling device for a timber truck with a trailer has been proposed.

РЕЗУЛЬТАТЫ ИССЛЕДОВАНИЯ ДВИЖЕНИЯ ЛЕСОВОЗНОГО АВТОПОЕЗДА, ОБОРУДОВАННОГО СЕДЕЛЬНО-СЦЕПНЫМ УСТРОЙСТВОМ С ПРУЖИННЫМ АМОРТИЗАТОРОМ

Based on the analysis of scientific works of foreign authors, the main factors influencing the efficiency of the operation of timber tractors with semi-trailers have been identified. A promising design of a fifth wheel coupling with a spring shock absorber for timber tractors with semi-trailers that haul timber in difficult road conditions is proposed. A mathematical model of the movement along a logging road of a logging tractor with a semi-trailer equipped with a fifth wheel coupling with a spring shock absorber has been developed. Based on the developed computer program, a preliminary assessment of the performance indicators of the proposed design of the coupling device was carried out. It has been established that the spring shock absorber of the fifth wheel coupling provides, during braking and acceleration, a decrease in the amplitude of acceleration oscillations between a timber tractor and a semi-trailer with timber in the range from 0.95 to 0.6 m/s2. It was found that in order to reduce unfavorable vibrations of a semi-trailer with timber relative to a timber tractor, it is advisable to use dry friction in a spring shock absorber.

ОЦЕНКА АКТУАЛЬНОСТИ ИСПОЛЬЗОВАНИЯ В КОНСТРУКЦИИ ЛЕСОВОЗНОГО ТЯГАЧА С ПОЛУПРИЦЕПОМ РЕКУПЕРАТИВНОГО ПНЕВМОГИДРАВЛИЧЕСКОГО СЕДЕЛЬНО-СЦЕПНОГО УСТРОЙСТВА

The main advantages of using timber tractors with semitrailers in comparison with single timber trucks and timber trucks with trailers are listed. The analysis of the results of scientific works of foreign authors engaged in increasing the efficiency of timber haulers with semi-trailers in the process of hauling timber is carried out. The existing conditions for the transportation of timber in the Russian Federation by timber haulers with semitrailers are considered. Described are the negative consequences that are manifested in the process of movement on forest roads, limiting the efficiency of using timber tractors with semi-trailers. Among them, the most significant one is highlighted, which consists in the occurrence of significant efforts when braking a timber tractor with a semitrailer in a fifth wheel coupling, accompanied by the appearance of cracks in the elements of the supporting system, breakdowns in the coupling device, as well as folding of the timber road train. The schemes of forces acting on a timber tractor with a semitrailer during braking are presented. The dependences of the change in the braking forces of the axles of a timber tractor with a semitrailer are given, taking into account the non-simultaneous operation of their braking mechanisms, as well as the change in the force in the fifth wheel coupling of a timber tractor with a semitrailer during braking. In order to increase the efficiency of a logging tractor with a semitrailer, a promising design of a recuperative fifth wheel coupling has been proposed.

The physics potential of a reactor neutrino experiment with Skipper-CCDs: searching for new physics with light mediators

We explore the sensitivity to new physics of the recently proposed vIOLETA experiment: a 10 kg Skipper Charged Coupled Device detector deployed 12 meters away from a commercial nuclear reactor core. We investigate two broad classes of models which benefit from the very low energy recoil threshold of these detectors, namely neutrino magnetic moments and light mediators coupled to neutrinos and quarks or electrons. We find that this experimental setup is very sensitive to light, weakly coupled new physics, and in particular that it could probe potential explanations of the event excess observed in XENON1T. We also provide a detailed study on the dependence of the sensitivity on the experimental setup assumptions and on the neutrino flux systematic uncertainties.