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A dynamic modeling method for Multistage Planetary Gear Transmission (MPGT) is proposed based on the concept of integral planetary gearbox modeling. The integrated interaction of multiple nonlinear parameters is considered in the dynamic model. The time-varying mesh stiffness of each gear pair is calculated by the energy method. The effects of input torque, gear backlash, and meshing damping on the chaos and impact characteristics of the system are analyzed in detail. The results show that the dynamic behavior of the system is closely related to the Dynamic Meshing Force (DMF). When the system is in the states of chaos, bifurcation, and jumping, the DMF fluctuates violently, and the stability and reliability of the system are seriously affected. With the increase of input torque and meshing damping, the system exits chaos through the inverse period-doubling bifurcation path, which indicates that increasing the input torque and meshing damping can suppress the chaotic motion and enhance the stability of the system. The backlash has a significant effect on the nonlinear behavior and meshing impact characteristics of the system. When the backlash is small, the system is in bilateral impact, and the meshing impact tends to be stable as the backlash increases. In order to improve the vibration characteristics of the system, a slightly larger backlash is necessary. The results can be used to guide the dynamic characteristics design and vibration control of the MPGT. [ABSTRACT FROM AUTHOR]

The expression 'anti-gender campaigns' has rapidly made its way to describe a new and specific wave of activist and policy initiatives against gender and sexual equalities. The goals of this article are twofold: to offer a close examination of the current state of anti-gender campaigns in Europe, and to look back at the scholarship produced in the last decade. Following the historical unfolding of these campaigns, this article explores four scenes that are crucial to contemporary anti-gender politics: churches, social movements, political parties and states. By emphasising that anti-gender campaigns encompass a wide diversity of political projects, it insists on the need to consider this plurality as constitutive of the phenomenon, a goal that requires to pay more attention to the actors who use them and the ways they do it. Rather than a discussion of new empirical material, this article invites scholars to reflect on the ways to approach these developments and offers a critical overview of existing scholarship. It shows that these campaigns are a transnational kit highly adaptable to local circumstances, and that these campaigns are simultaneously about and not about gender, gender being – following Joan W. Scott's seminal reading – 'a primary way of signifying relationships of power'. Using the novel Frankenstein, this article finally argues that anti-gender campaigns are no longer under the control of their creator – the Catholic Church – but, like the creature invented by Mary Shelley, they live an emancipated and autonomous life. [ABSTRACT FROM AUTHOR]

Rattling is a perennial gear noise problem observed in various powertrain components ranging from manual transmissions to engine balancers and timing gear trains. Under lightly loaded conditions, gear systems that are subjected to input and/or output torque fluctuations exhibit vibro-impacts as tooth separations and coast-side contacts take place in the presence of backlash. Experimental set-ups that can impose tightly controlled torque fluctuations to single or multi-mesh gear train are used here to determine the sensitivity of the rattling noise levels to the magnitudes of backlash within wide ranges of torque fluctuation parameters. Torsional discrete models of the experimental set-ups were used to simulate these rattling motions and to predict impact velocity-based rattle severity indexes as a function of both excitation parameters and backlash magnitudes. Single-mesh results show that the larger backlash values result in higher noise levels in most of the cases. In case of double-mesh systems, the resultant noise levels and the corresponding rattle indices exhibit different sensitivities to backlash magnitudes depending on the excitation conditions. [ABSTRACT FROM AUTHOR]

We report the first investigation of whether observers draw information about mindsets from behavior, specifically prejudice confrontation. We tested two questions across 10 studies (N = 3,168). First, would people who observe someone confront a biased comment (vs. remain silent) see them as endorsing more growth (vs. fixed) mindsets about prejudice and bias? If so, would the growth mindset perceptions that arise from confrontation (vs. remaining silent) attenuate the backlash that observers exhibit against confronters? We investigated these questions using scenarios (Studies 1, 2a–b, 4, 5a–d), naturalistic confrontations of national, race, and gender stereotypes reported retrospectively (Study 3), and an in-person laboratory experiment of actual confrontations of racial bias (Study 6). Correlational and experimental methods yielded support for our core hypotheses: People spontaneously imbue someone who confronts a biased comment with more growth mindset beliefs about prejudice and bias (Studies 1, 2a–b, 4, 6), regardless of whether participants observe the confrontation (Studies 1, 2a–b, 5a–d) or are being confronted themselves (Studies 2a–4, 6). The growth mindset perceptions arising from these confrontations suppress backlash, assessed by classic interpersonal perceptions (Studies 4–5) and judgments of interpersonal warmth and willingness to interact again in the future (Study 6), both when the confronter was a target of the biased behavior (Studies 1–5), and when they were an ally (Study 6), in both correlational studies (Study 3–4) and when growth mindset (about personality, Study 5; about prejudice, Study 6) was manipulated, confirming causality. We discuss implications for the study of mindsets, confrontation, and intergroup relations. [ABSTRACT FROM AUTHOR]

The dual-motor drive is common in many heavy-duty swinging arm servo systems. A well-tuned dual-motor drive can provide better stability and durability than the regular single motor servo. However, the backlash is usually unavoidable in the heavy transmission chains. In this article, the issues provoked by the backlash are resolved by a virtual average motor model and a simple anti-backlash torsion torque. The transient performance is guaranteed by the dual-motor synchronous drive, and the anti-backlash strategy is only enabled when the load is approaching the reference position. The challenge is that the motion system structure is transforming during this transition. The model predictive control combined with the extended state observer is applied to get adaptive in this scenario. The expected effect is that the servo can track the desired position with high precision and high response. The scheme is comprehensively validated and evaluated in an experimental servo setup with a dual-motor drive. [ABSTRACT FROM AUTHOR]

The unfriendly-for-humans environment of space causes automatic or remotely controlled vehicles and devices to be used for its research. In robot and manipulator control systems, and also in mechanisms adjusting antennas and photovoltaic panels, the hermetic harmonic drive can be used. A special advantage of this type of gear is the ability to transfer power to an isolated space separated by physical barriers from external influences. Therefore, the purpose was to design gears that will allow achieving the highest kinematic precision for control systems by simultaneously maintaining their hermetics. The article presented an analysis of the kinematic accuracy of harmonic hermetic drives powered by four different types of wave generators. The generators used differed in construction but also caused other deformations of the flexspline. The calculation of angular displacement was prepared in the computer program Abaqus. The simulations were performed on virtual models of a complete harmonic hermetic drive using the finite element method (FEM). The results from the analysis allow the most favorable solution to be applied to the Mars rover drive or spacecraft control system. It was determined for which of the wave generators the kinematic accuracy is the highest and how high the backlash exists for the reversing rotation. Finally, the proposed design will allow one to increase the accuracy of the working movements and control of space vehicles while ensuring a minimal influence of the external ambient. [ABSTRACT FROM AUTHOR]

Despite high gender equality ratings, Sweden shows a high prevalence of intimate partner violence against women (IPVAW). Suggested factors underlying this apparent paradox include backlash effects against women's empowerment. This study explores stories of backlash in interviews with 23 IPVAW survivors in Sweden. Thematic analysis identified categories of narrative segments referring to phenomena provoking violence; the victims' resources, agency, breaking with gender norms and resistance, and the partner's feelings of subordination, while case-centered narrative analysis pointed to divergences between how these categories appear in the stories. The study underscores the complexity of links between gender (in)equality and IPVAW in Sweden. [ABSTRACT FROM AUTHOR]

Meshing backlash mainly determines the transmission accuracy of harmonic drive, which is an important index in design. In this paper, a design method for short tooth involute profile is proposed. By intercepting part of the tooth profile, meshing interference of the addendum can be effectively avoided. Based on the dimensions of over pins of circular spline and flexspline, a calculation method of tooth thickness deviation is proposed, and the positive and negative tooth thickness deviation are defined. Involute functions need not be calculated by this method, which simplifies the solution process. By discretizing the teeth profile points of circular spline and flexspline, a calculation method of time-varying backlash is proposed, the variation of backlash in meshing in and out is analyzed, and the influence law of tooth thickness deviation on backlash is studied. On this basis, an algorithm for adjusting the radial deformation to compensate for the backlash is proposed. The results show that the excessive backlash in the meshing area can be reduced by increasing the radial deformation. When meshing interference occurs, the interference-free meshing can be realized by decreasing the radial deformation. [ABSTRACT FROM AUTHOR]

Within a democracy, reactions to State acts are expected and even desirable. Despite that, these reactions can acquire contours of different intensities, and at their limit, they can even cause social upheavals and setbacks in acquired rights. The reaction to judicial acts, in particular, have been studied by specialized literature under the nickname of backlash or backlash effect. In a context of cooling of the process of expansion of democratic ideas and regimes, and still under the influence of political communication through the internet and social networks, the backlash is analyzed here according to its insertion in the theories of Ronald Dworkin, Michael Klarman's, Cass Sunstein and Robert Post and Reva Siegel. Then, with the theoretical framework defined, this article is directed to the study of the political repercussion triggered around Inquérito 4.781, the so-called "Inquérito das fake news", which runs under secrecy in the Federal Supreme Court. Without ignoring the limitations of access to the entire content of the Survey, the research that supports this article, focusing on its political reverberations, was based on the qualitative research strategy proposed by Samuel Sales Fonteles and on the study of speeches given about the Survey, with the purpose of evaluating whether the backlash phenomenon has been verified in this case and its possible impact. The hypothesis is that the reactions to the inquiry constituted a form of low or medium impact backlash, specifically driven by the current President of the Republic and his allies. [ABSTRACT FROM AUTHOR]

The present paper presents aspects related to the analysis of the cylindrical gears of the central drum gear of the sled-type forestry cableway. This analysis helps to choose and correctly size the gear in the cableway winch drum. Based on the analysis performed on the gears teeth shapes, the analysis of the gear lubrication, and the analysis of the backlash of the teeth the final shape of the gear drive system will be presented. At the end of the work, the analysis with finite elements of the cylindrical gear is presented in order to obtain the optimal structure. [ABSTRACT FROM AUTHOR]

In this essay we outline five constellations of poetic and visual practices, starting with the dictatorship in Chile (1973-1990), but connecting them with works from previous decades. Without wanting to be exhaustive, our intention is to show how poetry and related practices have shaped a creative response of counterattack and antithesis, as well as resistant ways of life through art at different times and areas of Chile. [ABSTRACT FROM AUTHOR]

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Copyright of Anuario Colombiano de Derecho Internacional is the property of Colegio Mayor de Nuestra Senora del Rosario and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dynamics of suspended cables with active vibration control is studied. The control device is an electrical vibration absorber that is driven by a motor and that may be fixed at any position along the cable. The absorber applies a control force that reduces vibration amplitude at the position where it is placed. The methodology is efficient for attenuating high-frequency, low-amplitude vibration due to periodic excitation that may consider wind effect. The dynamic behavior is described by a mechanical model of the absorber and the cable at the location where the absorber is attached. The model takes into account such practical problems as time delay and backlash at the driving, which lead to limitation in the applicability of control. Time delay occurs in digital control, because samples of data are taken at discrete time intervals and response is provided after the sampling delay. Backlash influences control when the direction of control force changes, since the control force is not transmitted in the small domain of backlash. The present research examines the effects of time delay and backlash on the local control of cable vibration, and assesses the range of time delay and backlash when the control can be applied successfully. Moreover, the presence of time delay and backlash together results in a motion with some irregularity what justifies the detailed study of the dynamic behavior in order to evaluate the types of motion that may arise in such systems. [ABSTRACT FROM AUTHOR]

This study tries to reveal the backlash contained in Habiburrahman El Shirazy’s novel, Cinta Suci Zahrana. The novel is mostly viewed as promoting feminist values in which the main character is fighting for her dream in education. However, it carries backlash, which is defined as a counter assault toward woman’s progress. In Faludi’s theory, backlash, taking form in myth constructed by patriarchal culture, is used to spread believes that progress women made cause only misery. It is trying to put woman back to inferiority by showing that what they are trying to achieve can make them suffer. This sudy investigates whether the ideas containing backlash appear in Habiburrahman’s Cinta Suci Zahrana. By using qualitative methods and deconstruction reading, this study reveals a discourse that seems to be about women’s struggle, yet carries backlash which takes a form of consequences of the struggle. The result shows that there are backlash ideas taking form as consequences the main character, Zahrana, has to suffer because of her persistence in pursuing her study. Revealing the backlash and how it is presented, this study offers different point of view, not from religious context but limiting the discussion in cultural context. The result is expected to promote critical reading and becomes a contribution to research about backlash.

This article considers the feasibility of restoring and maintaining the kinematic accuracy of the support-rotary device drives by introducing a backlash compensation device into the control system. The power electromechanical drives of support-rotary device considered in this article contain two motors, the summation of the torques of which is carried out on a common output shaft. It is shown that the restoration of the required kinematic accuracy of the drives can be achieved by introducing one of two variants of an electronic device for backlash compensation into the control system. In the first variant, equal and opposite displacement signals are introduced into the control signals of the motors. The second variant introduces an electronic cross-connections backlash compensation scheme was into the control system. The study of the operation of the support-rotary device drive system with two backlash compensation devices carried out by a simulation method showed that the use of a cross-connection scheme is the most preferable and effective. As a result of the research, it was shown that the introduction of an electronic backlash compensation device into the control system makes it possible to ensure the operability of the power electromechanical drives of a support-rotary device with initial kinematic accuracy.

• New vibration control is developed for a nonlinear drivetrain with backlash. • Backlash is effectively handled by controller-switching-based compensation. • The controller parameters are efficiently optimized by AGWO. • The proposed approach is experimentally verified. • Comparative experiments show the effectiveness of the proposed approach. The controller optimization task is rarely spotlighted despite its importance for vehicle drivetrain mechanisms although many studies have been dedicated to developing vibration control strategies. Based on the adaptive grey wolf optimizer (AGWO), this research develops a fast-optimization scheme for a drivetrain oscillation control system that simultaneously addresses effects of nonlinear backlash. A drivetrain system model governed by a backlash nonlinearity is presented, and a baseline controller is derived for damping low-frequency drivetrain resonance based on the optimal H 2 synthesis. The introduction of a time-dependent-switched Kalman filter realizes a solution for dealing with the nonlinear backlash issue, relying on straightforward controller-switching-based compensation for the backlash and contact modes. Optimal solutions for the control system parameters are efficiently obtained using AGWO. AGWO exhibits both global search capability and superior computational efficiency because of its systematic stopping criteria and adaptive exploration/exploitation parameter. This study improves the efficiency of optimizing active drivetrain vibration control by introducing the adaptive mechanism into the controller parameter tuning. Comparative experiments demonstrate that the AGWO-based scheme provides a sufficiently good controller with the fastest time. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper deals with the interconnection between a linear system and a nonlinear operator consisting of asymmetric input backlash and asymmetric dead-zone. The uniform ultimate boundedness of the system is studied. A piecewise quadratic Lyapunov function, suitable with the polyhedral description of the nonlinear operator is proposed. The conservatism of existing results is therefore reduced. The effectiveness and improvement of the results are assessed using a numerical example. [ABSTRACT FROM AUTHOR]

Effectively delegating work to others is considered critical to managerial success, as it frees up managers’ time and develops subordinates’ skills. We propose that female leaders are less likely than male leaders to capitalize on these benefits of delegating. Although delegation has communal (e.g., relational) and agentic (e.g., assertive) properties, we argue that female leaders, as compared to male leaders, find it more difficult to delegate tasks due to gender-role incongruence. In five studies, we draw upon social role and backlash theories to show that women imbue delegation with more agentic traits, have more negative associations with delegating, and feel greater guilt about delegating than men. These associations result in women delegating less than men and, when they do delegate, having lower-quality interactions with subordinates. We further show that reframing delegation as communal attenuates women’s negative associations with delegation. These findings reveal that even when a given behavior has both agentic and communal elements, perceptions of agency can undermine women’s engagement in them. However, emphasizing the communal nature of seemingly agentic acts may encourage women’s engagement in such critical leadership behaviors. These findings have theoretical and practical implications for research on gender differences and leadership behavior in the workplace. [ABSTRACT FROM AUTHOR]

This article draws on Diane Negra's (2009) assessment of neo-global postfeminist popular culture and cinema as displaying an obsession with time-control that is largely inimical to feminist progress, arguing that similar currents are visible in 2010s French screen romances. While manifestations of this obsession with relevance for the contemporary French context range from celebrations of ritualized, time-sensitive milestones (marriage, pregnancy) to narratives of female professional retreatism in the face of 'time-poverty' or the expansion of sexualized female identities across ages, this article focuses in depth on themes of actual or symbolic historical reversion in the intimate sphere through a close analysis of the films Camille redouble (Noémie Lvovsky, 2012) and Un peu, beaucoup, aveuglément (Clovis Cornillac, 2015). After surveying other cognate fictions, the discussion demonstrates that both these films reflect a wider backdrop of time-related trauma informing contemporary French onscreen romance and are accordingly melancholic, as well as openly nostalgic, in theme and tone. The article interrogates the backlash aspects of such narratives but also the different resonances associated with regressive 'postfeminist' elements in French as opposed to American culture. It thus demonstrates that postfeminism bears a specific relationship to the distinctive past history comprised by local feminist movements and intersects with other Gallic customs and ideologies – notably nationalistic ones – in particular ways. [ABSTRACT FROM AUTHOR]

This article aims at the difficulties of wheeled mobile robots (WMR) system with wheeled slipping and control backlash in trajectory tracking. A novel sliding mode control strategy is proposed. For estimating the lumped disturbance, an adaptive sliding mode disturbance observer is constructed and achieves the finite‐time convergence of estimate error. For the purpose of accelerating the trajectory tracking, a novel arctangent terminal sliding mode surface is designed. To overcome the control chattering, a novel super‐twisting sliding mode controller is constructed which makes the control effect continuous and achieves finite‐time tracking of virtual reference velocities. The asymptotic convergence of trajectory tracking error is guaranteed by the Lyapunov stability theory. The simulation and comparison results of a WMR system demonstrate the validity of the proposed scheme for trajectory tracking. [ABSTRACT FROM AUTHOR]

To reveal the nonlinear dynamic behavior of gear rattling vibration caused by gear backlash, a 2-DOF oscillator model with spring and damping elements was established. Based on the theory of discontinuous dynamical systems, the phase plane of gear motion was divided into three parts: the domain of tooth surface meshing motion, the domain of free motion and the domain of tooth back meshing motion. Introducing the global mapping and local mapping dynamics method, the process of gear teeth from impact to meshing and then impact and meshing was accurately described. The influence of different restitution coefficients on gear impact-meshing motion was studied by numerical simulation. The results showed that the grazing bifurcation caused by gear backlash will lead to complex mapping structures of the system and even chaos. The restitution coefficient directly affects the impact-meshing behavior. The introduction of meshing stiffness and restitution coefficient can reasonably characterize the elastic deformation and energy loss during gear meshing, which provides a theoretical model for the application of the theory of discontinuous dynamical systems to a more complex multi-degree of freedom flexible contact gear transmission system. [ABSTRACT FROM AUTHOR]

In this paper, the problem of estimating the dominant image orientation (DIO) is experimentally investigated using the characteristics of the scattering ellipse of the gradient field components. According to these characteristics, the angle of rotation, the parameters of the shape of the Weibull distribution characterizing the blurring of the image, as well as the assessment of the sharpness of the DIO angle determination, are estimated. The results of an experimental study of the properties of DIO in various situations, such as the implementation of rotations of texture and other types of images by various methods, the presence of distorting noise, etc. are given. Using the Photoshop software system, the results of applying the previously proposed approach to assessing the quality of image rotation algorithms called the "backlash method", are studied. [ABSTRACT FROM AUTHOR]

The gender gap in voting for far-right parties is significant in many European countries. While most studies focus on how men and women differ in their nationalist and populist attitudes, it is unknown how the socio-economic and political promotion of women is associated with the gender gap in far-right political orientation. The following paper compares the effect of four different spheres of gender equality on this gender gap. By estimating multilevel logit models for more than 25 European countries and testing the mechanism via a socially conservative attitude toward gendered division of work, I find that the visible field of representation in particular—measured by the share of women in parliament and women on boards—is associated with a gender gap in far-right orientation. This paper contributes to the literature in two important ways: first, it combines policy feedback with cultural backlash theory, enlarging the scope of both theories; second, it demonstrates the importance of gender equality policies for the study of the far-right gender gap. [ABSTRACT FROM AUTHOR]

The argumentation in this paper is based on the proposition that constitutions play a key role in defining the approach to women's social status, not just by determining ordinary legislation and public policy, but also through constitutional review. The focus is on Hungary, a country that is not famous in Europe for a high level of equality between men and women, surrounded by a (liberal) international political discourse which asserts a backlash and claims that women's equal rights are being curtailed even more during the era of Orbán's illiberal government. Against this discursive backdrop, the paper highlights a counterintuitive phenomenon: since the democratic transition (1989-1990) all the key constitutional disputes related to equality between the sexes have been initiated by men claiming instances of discrimination against men, as if women were too privileged in Hungary. A relevant contextual feature is that while equal legal standing for the sexes is guaranteed (due partly to the heritage of state socialism, then to efforts related to EU integration), affirmative measures for women are also constitutionally ensured. The Constitutional Court has deployed surprisingly poor-quality reasoning in these disputes, suggesting that it never considered equality between the sexes to be an important issue. This leads us to claim that certain persistent features have characterized this field since the 1990s, not the dynamics of reversal since the 2010s. With our empirical findings, we aim to contribute to the academic discourse in a way that challenges the backlash narrative regarding developments in Hungary from a specific perspective. [ABSTRACT FROM AUTHOR]

In this paper the analysis of backlash influence on the spectrum of torque at the output shaft of a cycloidal gearbox has been performed. The model of the single stage cycloidal gearbox was designed in the MSC Adams. The analysis for the excitation with the torque and the analysis with constant angular velocity of the input shaft were performed. For these analyses, the amplitude spectrums of the output torque for different backlashes was solved using FFT algorithm. The amplitude spectrums of the combined sine functions composed of the impact-to-impact times between the cycloidal wheel and the external sleeves were computed for verification. The performed studies show, that the backlash has significant influence on the output torque amplitude spectrum. Unfortunately the dependencies between the components of the spectrum and the backlash could not be expressed by linear equations, when vibrations of the output torque in the range of (350 Hz - 600 Hz) are considered. The gradual dependence can be found in the spectrum determined for the combined sine functions with half-periods equal impact-to-impact times. The spectrum is narrower for high values of backlash. [ABSTRACT FROM AUTHOR]

Gear backlash is a quite serious problem in industrial robots, it causes vibrations and impairs the robot positioning accuracy. Backlash estimation allows targeted maintenance interventions, preserving robot performances and avoiding unforeseen equipment breakdowns. However, a direct measure of the backlash is hard to obtain, and dedicated auxiliary sensors are required for the measurement. This paper presents a method for estimating backlash in robotic joints that does not require the installation of extra devices. It only relies on data gathered from the motor encoder, which is always present in a robotic joint. The approach is based on the observation of a characteristic vibration pattern arising on the motor speed signal when backlash affects the joint transmission. By looking at the amplitude of this vibration some information about the entity of the backlash in the joint is gathered. Experimental results on simulated data are reported in the study to show the robustness of the method, also with respect of noise. Furthermore, tests on real-world data, gathered from robots installed in a production plant, demonstrate the efficacy of the technique. The approach is cost-effective, fast, and easily automatable, therefore convenient for the industrial world. [ABSTRACT FROM AUTHOR]