ХАРАКТЕРИСТИКИ БОКОВОЙ РЕАКЦИИ ПРИ ИЗМЕНЕНИИ ТЕХНИЧЕСКОГО СОСТОЯНИЯ АМОРТИЗАТОРА

The article presents an analytical study of the influence of the technical condition of the shock absorber on the characteristics of lateral reaction change in the spot of contact of the elastic tire with the support surface. The process of moving the car around a circle with passing along a single road ledge is the object of research. The change in lateral reaction over time is a diagnostic parameter for monitoring the technical condition of the damper. Sensitivity and unambiguity of diagnostic parameter are calculated.Purpose. The theoretical justification for the method of diagnosing a car’s suspension depending on changes in lateral reactions at the point of contact of the wheel with the road.Methodology includes numerical methods for solving differential equations, methods of mathematical modeling and mathematical analysis.Results: the mathematical apparatus for an analytical research of sensitivity and unambiguity of lateral reactions of the car at change of parameters of technical condition of shock absorbers.Practical implications: organizations and institutions that develop vehicle diagnostic techniques can use the results.В статье представлено аналитическое исследование влияния технического состояния амортизатора на характеристики изменения боковой реакции в пятне контакта эластичной шины с опорной поверхностью. Исследуется процесс движения автомобиля по окружности с переездом единичной неровности. Предложено использовать зависимость боковой реакции от времени в качестве диагностического параметра для контроля технического состояния амортизатора. Выполнена оценка чувствительности и однозначности рассматриваемой зависимости.Цель – теоретическое обоснование метода диагностирования подвески автомобиля по изменению боковых реакций в пятне контакта колеса с дорогой.Методы проведения работы: использованы численные методы решения дифференциальных уравнений, методы математического моделирования и математического анализа.Результаты: разработан математический аппарат для аналитического исследования чувствительности и однозначности боковых реакций автомобиля при изменении параметров технического состояния амортизаторов.Область применения результатов: результаты могут быть использованы организациями и учреждениями, занимающихся разработкой методов диагностирования автотранспортных средств

МАТЕМАТИЧЕСКАЯ МОДЕЛЬ ПРОЦЕССА ДВИЖЕНИЯ АВТОМОБИЛЯ ПО ПОПЕРЕЧНОМУ УКЛОНУ

The article presents an analytical study of the influence of the technical state of the suspension system on the stability parameters of the vehicle. The process of movement along the transverse slope with the disturbed state of the suspension is investigated. It is proposed to use the values of the lateral displacement, the angle of rotation and the time of the transient process of the angular velocity as the estimated parameters of motion stability.Purpose – Theoretical substantiation of the method for diagnosing the suspension by the kinematic parameters of the vehicle.Мethodology includes methods of mathematical modeling and numerical methods for solving differential equations.Results: a mathematical apparatus was developed for the analytical study of the process of vehicle movement when changing the parameters of the technical state of shock absorbers.Practical implications: the results can be used by organizations and institutions involved in the development of diagnostic methods for vehicles. В статье представлено аналитическое исследование влияния технического состояния системы подрессоривания на параметры устойчивости автомобиля. Исследуется процесс движения по поперечному уклону при возмущенном состоянии подвески. В качестве оценочных параметров устойчивости движения предложено использовать величины бокового смещения, угла поворота и времени переходного процесса угловой скорости.Цель – Теоретическое обоснование метода диагностирования подвески по кинематическим параметрам автомобиля.Методы проведения работы: использованы методы математического моделирования и численные методы решения дифференциальных уравнений.Результаты: разработан математический аппарат для аналитического исследования процесса движения автомобиля при изменении параметров технического состояния амортизаторов.Область применения результатов: результаты могут быть использованы организациями и учреждениями, занимающихся разработкой методов диагностирования автотранспортных средств

A hall plate based instrument to measure the snapback in the Large Hadron Collider superconducting dipole magnets

The decay and snapback of the magnetic field multipoles in superconducting particle accelerators like the Large Hadron Collider (LHC) could result in a significant particle beam loss unless adequately compensated. Whilst standard instrumentation used to measure the field quality of the superconducting magnets is good enough to measure the harmonic decay, it is not fast enough to measure the snapback. Therefore, a state of the art instrument was recently developed at CERN to measure the most important harmonics with a high measurement frequency and hence improve the understanding of the snapback phenomenon. In this paper we describe the instrument's principle of operation, its mechanical arrangement, its compensation system and its digital acquisition system. We also compare the performance of two different techniques implemented to achieve the necessary measurement resolution of 6 orders of magnitude lower than the main superimposed dipole field.peer-reviewe

Ion Migration Polarization in the Yttria Stabilized Zirconia Based Metal-Oxide-Metal and Metal-Oxide-Semiconductor Stacks for Resistive Memory

We report the investigations of the ion migration polarization in the yttria stabilized zirconia (YSZ) thin films in the Metal-Oxide-Metal (MOM) and Metal-Oxide-Semiconductor (MOS) stacks due to the drift of the oxygen vacancies under the external bias voltage applied between the electrodes. The parameters characterizing the drift of the oxygen vacancies in YSZ such as the ion drift activation energy, mobile ion concentration, and the drift mobility have been determined in the temperature range 300–500 K. These data are important for deeper understanding of the fundamental mechanisms of the electroforming and resistive switching in the YSZ-based MOM and MOS stacks, which are promising for the Resistive Random Access Memory (RRAM) and other memristor device applications

Spark Plasma Sintering and Hot Pressing of Cu+Al Powder Mixtures and Pre-Deposited Cu/Al Layers

Reactive processing of metals is interesting for materials design and achieving new sets of properties. The transformation degree of the metals, the factor governing the properties of the material as a whole, depends on the sintering/heat treatment conditions. In the present investigation, the phase and microstructure formation of materials obtained by sintering of Cu-10 wt.% Al mixtures and layered Cu/Al structures under different modes of pressing/heating is presented. The samples were obtained via spark plasma sintering (SPS), hot pressing (HP) and pressureless sintering. The products of the interaction between the metals were Al2Cu and Cu9Al4 intermetallics and Cu(Al) solid solutions. The influence of the consolidation method on the phase composition of the sintered materials was studied. The hardness of the composites was analyzed in relation to their structural features. A model experiment has been conducted to trace the structural evolution at the Cu/Al interface caused by interdiffusion. The Cu/Al layered structures obtained by detonation spraying of the powders on a steel substrate were treated by SPS or HP. The effect of electric current, which is a feature of SPS processing, was in accelerating the reaction product formation in the layered structures still containing the starting metallic reactants

Silicon-Compatible Memristive Devices Tailored by Laser and Thermal Treatments

Nowadays, memristors are of considerable interest to researchers and engineers due to the promise they hold for the creation of power-efficient memristor-based information or computing systems. In particular, this refers to memristive devices based on the resistive switching phenomenon, which in most cases are fabricated in the form of metal–insulator–metal structures. At the same time, the demand for compatibility with the standard fabrication process of complementary metal–oxide semiconductors makes it relevant from a practical point of view to fabricate memristive devices directly on a silicon or SOI (silicon on insulator) substrate. Here we have investigated the electrical characteristics and resistive switching of SiOx- and SiNx-based memristors fabricated on SOI substrates and subjected to additional laser treatment and thermal treatment. The investigated memristors do not require electroforming and demonstrate a synaptic type of resistive switching. It is found that the parameters of resistive switching of SiOx- and SiNx-based memristors on SOI substrates are remarkably improved. In particular, the laser treatment gives rise to a significant increase in the hysteresis loop in I–V curves of SiNx-based memristors. Moreover, for SiOx-based memristors, the thermal treatment used after the laser treatment produces a notable decrease in the resistive switching voltage