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Objective To address the issue of low-frequency train oscillation on Chongqing Rail Transit Line 1 (hereinafter as ′Line 1′), it is necessary to analyze the causes of the oscillation and formulate appropriate rectification measures. Method The causes of low-frequency train oscillation on Line 1 are analyzed by examining oscillation characteristics, track geometry, bridge vibration, and rail profile changes, rail grinding measures are formulated. The causes of periodic rail wear from both track and vehicle perspectives are explored, and measures to address train oscillation caused by periodic rail wear are proposed. Result & Conclusion The causes of low-frequency train oscillation on Line 1 include: track geometry irregularities and bridge vibrations that do not directly cause abnormal vehicle oscillation; since the rail profile exhibiting periodic changes with a wavelength of approximately 12 meters, at higher train speeds and under rail profile periodic variation action, the lateral natural mode with a vehicle frequency of 2 Hz will be activated, leading to severe carbody oscillation. Through the rail grinding plan, the vehicle operation stability index after grinding decreases by about 0.5 compared to before grinding, with all the stability indices within the grinding section remaining below the limit of 2.5, thus alleviating the oscillation problem. The significant track geometry irregularities and the vehicle poor disturbance-resistant performance are identified as causes of periodic rail wear. The combination of rail milling and track fine adjustment measures can completely resolve the train oscillation issue caused by periodic rail wear.

According to the principle of forming principle and modeling method of the cycloidal gear tooth profile,the mathematical model of the form grinding is established and the calculation formulas for axial section coordinate points of the grinding wheel are deduced. The profile equation of the grinding wheel is obtained through studying the theory of grinding wheel widened. The trajectory for the diamond wheel when dressing grinding wheelis solved based on the principle of equal distance curve. The software for form grinding wheel dressing is developed and the simulation and analysis of grind wheel modified is got by the modification method of "isometric + shift".

On the basis of a large number of reference,the research trends on modification of cycloidal gear,the accuracy control of cycloidal gear transmission and the dynamics of RV reducer is introduced,and the analysis and discussion on the key technology of the modification,manufacturing and manufacturing equipment development need to be solved of the cyclonical-pinwheel transmission is carried out.

The current study examined the mediating roles of emotion regulation strategies (i.e., cognitive reappraisal and expressive suppression) and resilience in the relationship between perceived parental support and depressive symptoms among college students during the first wave of the COVID-19 pandemic in China. A large sample of Chinese college students (N = 2, 423) participated in this investigation. Results indicated that perceived parental support was negatively related to depressive symptoms. The two emotion regulation strategies and resilience partially and serially mediated the relation between perceived parental support and depressive symptoms. Theoretical and practical implications of these results are discussed.

The current study examined the mediating roles of emotion regulation strategies (i.e., cognitive reappraisal and expressive suppression) and resilience in the relationship between perceived parental support and depressive symptoms among college students during the first wave of the COVID-19 pandemic in China. A large sample of Chinese college students (N = 2, 423) participated in this investigation. Results indicated that perceived parental support was negatively related to depressive symptoms. The two emotion regulation strategies and resilience partially and serially mediated the relation between perceived parental support and depressive symptoms. Theoretical and practical implications of these results are discussed., Author(s): Baojuan Ye [sup.1] , Shunying Zhao [sup.1] , Yadi Zeng [sup.1] , Chuansheng Chen [sup.2] , Yanzhen Zhang [sup.3] Author Affiliations: (1) grid.411862.8, 0000 0000 8732 9757, Center of [...]

Objective To describe a tobacco cessation intervention using personalized mobile phone text messages based on behaviour change theory and to assess why the intervention was effective. Methods We conducted a two-arm, double-blind, randomized controlled trial in five cities in China from April to July 2021. We recruited daily or weekly smokers aged 18 years or older. The 90-day intervention was delivered using a mobile phone chat application. At different stages of quitting, intervention group participants received personalized text messages based on analyses of the strength of their intention to quit, their motivation to quit and their self-reported success at quitting. Control group participants received non-personalized text messages. The primary outcome was the biochemically verified 6-month abstinence rate. Secondary outcomes were changes in scores on the components of protection motivation theory. All analyses were by intention to treat. Findings We randomly assigned 722 participants to intervention or control groups. Biochemically verified continuous abstinence at 6 months was 6.9% (25/360) in the intervention group and 3.0% (11/362) in the control group. Smokers who received the personalized intervention had lower scores on intrinsic rewards of smoking and response costs of quitting in the protection motivation theory analysis. These two variables were also determinants of sustained abstinence, thus explaining why the intervention group had a higher quitting rate. Conclusion The study confirmed the psychological determinants of long-term abstinence from smoking and provided a framework to explore why such an intervention is effective. This approach may be applicable to the development or analysis of interventions targeting other health behaviours. Objectif Presenter une intervention de sevrage tabagique articulee autour de messages SMS envoyes sur les telephones mobiles et personnalises en fonction de la theorie du changement de comportement, puis determiner pourquoi cette intervention a porte ses fruits. Methodes Nous avons mene un essai controle randomise en double aveugle et a deux volets dans cinq villes de Chine entre avril et juillet 2021. Nous avons recrute des fumeurs quotidiens ou hebdomadaires ages de 18 ans et plus. L'intervention, qui s'etalait sur 90 jours, s'est deroulee par l'intermediaire d'une application de chat sur telephone mobile. A differents stades du sevrage, les participants du groupe d'intervention ont recu des messages SMS personnalises bases sur une analyse de leur degre de volonte et de leur motivation a arreter de fumer, mais aussi de leurs capacites autodeclarees a y parvenir. De leur cote, les participants du groupe de controle ont recu des messages SMS non personnalises. Le taux d'abstinence a six mois verifie par test biochimique constituait le critere d'evaluation principal. Les criteres d'evaluation secondaires etaient l'evolution des scores au niveau des composantes de la theorie de la motivation a la protection. Toutes les analyses reposaient sur l'intention de traiter. Resultats Nous avons reparti aleatoirement 722 participants entre groupes d'intervention et de controle. Le taux d'abstinence a six mois verifie par test biochimique s'elevait a 6,9% (25/360) au sein du groupe d'intervention et a 3,0% (11/362) au sein du groupe de controle. Dans le cadre de l'analyse fondee sur la theorie de la motivation a la protection, les fumeurs ayant fait l'objet d'une action personnalisee ont obtenu des scores plus faibles en matiere de recompense intrinseque provoquee par le tabagisme et de couts d'intervention du sevrage. Ces deux variables se sont egalement revelees decisives dans l'abstinence prolongee, ce qui explique pourquoi le groupe d'intervention a affiche un taux de sevrage plus consequent. Conclusion L'etude a confirme l'impact des determinants psychologiques de l'abstinence a long terme et fourni des pistes d'exploration des raisons pour lesquelles une telle action est efficace. Cette approche pourrait etre utilisee dans le developpement ou l'analyse d'interventions ciblant d'autres comportements lies a la sante. Objetivo Describir una intervencion para dejar de fumar mediante el uso de mensajes de texto personalizados para telefonos moviles basada en la teoria del cambio de conducta y evaluar por que la intervencion fue eficaz. Metodos Se realizo un ensayo aleatorizado, con enmascaramiento doble y con dos grupos en cinco ciudades de China entre abril y julio de 2021. Se preseleccionaron fumadores diarios o semanales mayores de 18 anos. La intervencion de 90 dias se realizo mediante una aplicacion de chat para telefonos moviles. En las diferentes etapas de abstinencia, los participantes del grupo de intervencion recibieron mensajes de texto personalizados segun los analisis de la fuerza de su intencion de dejar de fumar, su motivacion para dejar de fumar y su exito autoinformado al dejar de fumar. Los participantes del grupo comparativo recibieron mensajes de texto no personalizados. El criterio de valoracion principal fue la tasa de abstinencia verificada mediante pruebas bioquimicas a los 6 meses. Los criterios de valoracion secundarios fueron los cambios en las puntuaciones de los componentes de la teoria de la motivacion de proteccion. Todos los analisis se realizaron por intencion de tratar. Resultados Se asignaron aleatoriamente 722 participantes a los grupos de intervencion o comparativos. La abstinencia continua verificada mediante pruebas bioquimicas a los 6 meses fue del 6,9% (25/360) en el grupo de intervencion y del 3,0% (11/362) en el grupo comparativo. Los fumadores que recibieron la intervencion personalizada tuvieron puntuaciones mas bajas en las recompensas intrinsecas de fumar y en los costes de respuesta de dejar de fumar en el analisis de la teoria de la motivacion de proteccion. Estas dos variables tambien fueron determinantes de la abstinencia prolongada, lo que explica por que el grupo de intervencion tuvo una tasa de abstinencia mas elevada. Conclusion El estudio confirmo los determinantes psicologicos de la abstinencia del tabaco a largo plazo y proporciono un marco para explorar por que una intervencion de este tipo es eficaz. Este enfoque podria aplicarse al desarrollo o analisis de intervenciones dirigidas a otros habitos saludables., Introduction Tobacco use is still a major public health problem worldwide. The most common type of tobacco use is cigarette smoking, which is one of the leading preventable causes of [...]

The following article presents and corroborates an outcome space branch-and-bound algorithm for solving the general linear multiplicative programming problem (GLMPP). In this new algorithm, GLMPP is transformed into its equivalent problem by introducing auxiliary variables. To compute the tight upper bound for the optimal value of GLMPP, the linear relaxation programming problem is assembled by using bound and hull linear approximations. Furthermore, the global convergence and computational complexity of the algorithm are demonstrated. Finally, the soundness and advantage of the proposed algorithm are validated by solving a demonstrative linear multiplicative problem. [ABSTRACT FROM AUTHOR]

The on-demand jetting of high-viscosity liquid has significant applications in fields such as electronic packaging and bioprinting. Conventional methods for high-viscosity liquid jetting often employ a needle propelling the liquid rapidly, which demands high precision in the manufacturing and assembly of the needle and nozzle, and can potentially damage biomaterials. In this study, a novel method utilizing jet tube impact for on-demand high-viscosity liquid jetting is proposed, leveraging the inherent inertia of the liquid to generate the pressure pulse necessary for on-demand jetting. This method reduces the precision requirements for the device, enables device simplification, and avoids harm to biomaterials. The feasibility of this approach for on-demand high-viscosity liquid jetting is validated through experiments, and by combining numerical simulations, the jetting mechanism is revealed and primary factors influencing jetting performance are investigated. It is found that the water hammer pressure wave induced by the liquid inertia during the sudden velocity change of the jet tube is the predominant driving force for jetting, and the peak pressure can exceed 1 MPa and the peak jet velocity can exceed 15 m/s. An increase in the jet tube impact velocity and an extension of the acceleration duration at the same impact velocity both lead to an increase in the pressure wave amplitude. In addition, a decrease in the liquid level height shortens the period of the pressure wave. These factors all have an influence on the jetting performance. This study provides a new insight and theoretical foundation for the on-demand high-viscosity liquid jetting. [ABSTRACT FROM AUTHOR]

Inkjet printing technology has played an irreplaceable role in life science, precision manufacturing, and other frontier fields in recent years. However, the further development of this technology is limited by the fact that its printing resolution is difficult to raise to a higher level. The emerging satellite droplet printing technology offers a new approach for inkjet printing to break through the bottleneck of printing resolution limitations. In this paper, a symmetrical satellite droplet printing strategy is proposed. The effects of the geometric parameters of the satellite droplet generating device, the physical properties of the ink, and the operating parameters on the liquid bridge breakup process and the size of the satellite droplet are systematically studied. The phase field method and adaptive mesh refinement strategy are applied to solve the two-dimensional symmetrical model. The results indicate that the length of the liquid bridge, the radius of the bridge, the viscosity of the ink, and the drainage velocity are all positively correlated with the satellite droplet size, while the surface tension coefficient has a negative correlation with the satellite droplet size. Furthermore, the three-phase contact line at the orifice end will slip toward the center if the initial radius of the liquid bridge is quite large. Based on these investigations and discussions, a corresponding effective working space for satellite droplet printing is obtained, which lays the foundation for the popularization and further development of satellite droplet printing technology. [ABSTRACT FROM AUTHOR]