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Background: Detecting the main actors and important topics of Iranian cancer research is essential for Iranian policymakers, clinicians, and researchers. This study was conducted to demonstrate the trends and tops in Iranian cancer research from 1960 to 2018. Methods: A total of 22,370 Iranian cancer articles in Web of Science (WoS), PubMed, and Scopus, from 1960 through 2018, were extracted and preprocessed based on data mining techniques and analyzed using the collaboration network analysis, keywords analysis, and bibliometrics methods. Results: The results reveal that, Tehran University of Medical Sciences (11.46%) among organizations, Asian Pacific Journal of Cancer Prevention (5%) among journals, Malekzadeh R (1.09%) among authors, and Breast cancer (10.37%) among topics ranked the first. The trend of Iranian cancer research represents three periods: 1) germinating period, from 1970 to 2000, 2) developing period, from 2002 to 2014, and 3) flourishing period, from 2014 to 2018. It is expected that this trend will continue. The results indicate an average 12.8% increase in the logarithm of the count of articles published by Iranian cancer researchers each year. The findings are contextualized with Price’s publications trends principal for determining global and Iranian cancer research publication trends. Conclusion: The number of research papers published by Iranian researchers on cancer is increasing. In order to maintain the publication growth in this field, greater participation by other Iranian institutions is suggested. Although the quantity and quality of papers are increasing in some topics, certain topics and types of cancers should be still further studied and the Iranian policymakers should be encouraged to invest more in these topics. [ABSTRACT FROM AUTHOR]

Recently, hydraulic engine mounts have been used widely as an effective vibration isolator in automotive engines. They consist of two fluid chambers connected by an inertia track path and a decoupler mechanism with a floating plate. An ideal hydraulic mount should have high stiffness and damping at low frequencies and at high frequencies should act as a good isolator. Despite their acceptable performance, there are some drawbacks including switching, nonlinear behavior of the decoupler plate at low frequencies, and occurrence of the resonance due to the passage of the fluid through the decoupler in the high-frequency range. This paper proposes a new decoupler mechanism where the floating decoupler plate is replaced with a membrane where its tension could be controlled considering the operational frequency. Considering the discrete model of the operating fluid and the continuous model of the membrane, governing equations of the system are derived. By increasing the membrane tension at low frequencies, it is shown that the desired dynamic stiffness and damping can be achieved and the nonlinear switching behavior is eliminated. At the same time, by decreasing the membrane tension at high frequencies, it is shown that there is a significant increase in system compliance, resulting in better isolation. Results also show that the membrane replacement also eliminates the fluid resonances at high frequencies. Finally, the two-objective optimization method of the genetic algorithm is employed to find the optimal values of the membrane tension and the mount parameters. The results show that the proposed mechanism can be used as a suitable alternative to the conventional hydraulic mounts. [ABSTRACT FROM AUTHOR]

Reflections of the surface waves in hydraulic wave flumes could affect the performance of the common piston, hinged and plunger type wavemakers. This paper proposes a new wavemaker to produce surface waves where the possible reflections are barely able to affect its performance. The proposed wavemaker includes an oscillating paddle at the bottom of the flume where the produced upward flow induces travelling surface waves. An analytical study is carried out on the wave generation of the system. It is shown that the paddle length could significantly affect the height of the generated waves, which could not happen in conventional wavemakers. Effects of the water depth and the excitation frequency on the induced surface waves are also investigated. It is demonstrated that for a specific paddle length, water depth and forcing period the best performance of the system could be achieved. [ABSTRACT FROM AUTHOR]

A nonlocal elasticity theory is a popular growing technique for mechanical analysis of the micro- and nanoscale structures which captures the small-size effects. In this paper, a comprehensive study was carried out to investigate the influence of the nonlocal parameter on the bifurcation behavior of a capacitive clamped-clamped nano-beam in the presence of the electrostatic and centrifugal forces. By using Eringen's nonlocal elasticity theory, the nonlocal equation of the dynamic motion for a nano-beam has been derived using Euler–Bernoulli beam assumptions. The governing static equation of motion has been linearized using step by step linearization method; then, a Galerkin based reduced order model have been used to solve the linearized equation. In order to study the bifurcation behavior of the nano-beam, the static non-linear equation is changed to a one degree of freedom model using a one term Galerkin weighted residual method. So, by using a direct method, the equilibrium points of the system, including stable center points, unstable saddle points and singular points have been obtained. The stability of the fixed points has been investigated drawing motion trajectories in phase portraits and basins of attraction set and repulsion have been illustrated. The obtained results have been verified using the results of the prior studies for some cases and a good agreement has been observed. Moreover, the effects of the different values of the nonlocal parameter, angular velocity and van der Waals force on the fixed points have been studied using the phase portraits of the system for different initial conditions. Also, the influence of the nonlocal beam theory and centrifugal forces on the dynamic pull-in behavior have been investigated using time histories and phase portraits for different values of the nonlocal parameter. [ABSTRACT FROM AUTHOR]

The present paper deals with the study of nonlinear vibration of a functionally graded cantilever micro-beam imposed on a bias DC voltage and superimposed on a sinusoidal heat source. The governing equation of motion is derived extremizing the Lagrange's equation and Hamilton's principal under the assumption of Euler-Bernoulli beam theory. The thermo-elastic equation is obtained utilizing the first law of thermodynamics under the assumption of the classical Fourier heat conduction model. Due to the displacement dependency of the electrostatic force and time variability of the heat source, the governing differential equations of the system are nonlinear implicitly parametrically electro-thermo-elastic coupled equations. To evaluate the dynamic response of the micro-beam, the coupled equations are discretized applying a Galerkin-based reduced order model and then integrated numerically by the Runge-Kutta method. By solving the equations, the stable and unstable regions at different bias DC voltages are identified. By picking some special points from these regions and depicting the time history and phase portrait diagrams, their behaviors are investigated in detail. In addition to the classical dynamic pull-in, in which a homoclinic orbit separates stable periodic orbits from the unbounded solutions, a new kind of dynamic pull-in is presented, which separates unstable solutions, due to parametric resonance response, from unbounded rapidly growing solutions owing to the existence of saddle and singular fixed points in the system. [ABSTRACT FROM AUTHOR]

This paper deals with analysis of the mechanical behavior of an electro-statically-actuated micro-beam resonator from the bifurcation view of point. The non-local constitutive relation has been used to obtain the governing deformation equations. The obtained static equation has been solved using two approaches. The dynamic equation of motion has been solved applying a Galerkin-reduced order model. Bifurcation behavior of the beam subjected to an electrostatic force has been analyzed using the both approaches. The fixed points of the beam for given voltages have been obtained and stability of them determined by studying the phase portraits for each fixed point. [ABSTRACT FROM AUTHOR]

This paper studies the dynamic instability of cantilever micro-beam submerged in an incompressible viscous fluid cavity and actuated by electrostatic force. Equivalent squeeze film damping is incorporated in the vibrational equation of the micro-beam to obtain the natural frequencies of the coupled system. Then, imposing various step voltages, dynamic responses, and pull-in conditions of the micro-beam are studied. A parametric study is conducted to evaluate the effect of fluidic confinement on the instability voltage. Dielectric constant of the fluid proves dominantly influential compared with viscosity and density. In addition, values of pull-in voltage are seen to be highly dependent on the vertical position as well as the length of the micro-beam. [ABSTRACT FROM AUTHOR]

This paper reports a capacitive angular velocity trip sensor designed for protection of sensitive and accurate spinning equipment by utilizing alarm and trip. The recommended sensor can be able to measure rotating machinery angular speed and subsequently it sends alarm messages using LEDs and buzzers in the domain of an angular velocity that it can be programmable with micro-processer packages. Of course in the critical angular speed the sensor can trip the system. Moreover, the resolution of the trip sensor is determined and it is shown that with increasing of the width of the micro-beam high trip resolution is observed. [ABSTRACT FROM AUTHOR]