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The purpose of this is to study the mechanism of an oil film thickness formation in the nanoscale. A polar lubricant of propylene carbonate is used as the intervening liquid between contiguous bodies in concentrated contacts. A pressure caused by the hydrodynamic viscous action in addition to the double-layer electrostatic force, van der Waals inter-molecular forces and solvation pressure owing to inter-surface forces is considered when calculating the ultrathin lubricating films.

Using the Newton–Raphson iteration technique applied for the convergence of the hydrodynamic pressure, a numerical solution has been ascertained.

The results show that, at separations beyond about five molecular diameters of the intervening liquid, the formation of a lubricant film thickness is governed by the combined effects of viscous action and surface force of an attractive van der Waals force and a repulsive double-layer force. At smaller separations below five molecular diameters of the intervening liquid, the effect of the solvation force is dominant in determining the oil film thickness.

This paper fulfils an identified need to study the behavior of polar lubricants in concentrated contacts in ultrathin conjunctions. The effect of the hydrodynamic action, electrostatic force and surface action of van der Waals and solvation forces is considered when calculating the lubricant oil film thickness.

Electrostatic microelectromechanical systems are characterized by the pull‐in instability, associated to a pull‐in voltage. A good design requires an accurate model of this pull‐in phenomenon. The purpose of this paper is to present two approaches to building finite element method (FEM) based models.

Closed form expressions for the computation of the pull‐in voltage, can provide fast results within reliable accuracy, except when treating cases of extreme fringing fields. FEM‐based models come handy when high accuracy is needed. In the first model presented in this paper, the FEM is used to solve the electrostatic problem, while the mechanical problem is solved using a simplified Euler‐Bernoulli beam equation. The second model is a pure FEM model coupling the electrostatic and mechanical problems iteratively through the electrical force. Results for both scalar and vector potential formulations for the FEM models are presented.

In this paper a comparative study of simple pull‐in structures is presented, between analytical and 3D FEM‐based models. A comparison with analytical models and experimental results is also realized.

The coupling between the electrostatic and mechanical problem in the presented approaches, is iterative. Therefore, to improve the accuracy of the presented model, a strong coupling is needed.

In the presented FEM‐analytical model, the electrostatic problem is solved in both, scalar and vector electric potential formulations. This allows defining an upper and a lower limit for the electrostatic force and consequently for the pull‐in voltage.

The purpose of this paper is to discuss the numerical modelling of 3D structure of micro‐electro‐mechanical systems (MEMS) accelerometers. The general idea being discussed is the method of levitation force reduction, as the main source of incorrect mathematical model of comb drive structure.

Accelerometers design is a highly interdisciplinary area and, therefore, different methods and tools have to be exploited. Dynamic accelerometer behaviour modelling has been performed by use of a new object‐oriented model (NOOM), based on complex computer field and mechanical models.

The paper describes methods of levitation force reduction in electrostatic comb drive structures based on electrostatic structural models and finite elements method.

In the present work, the authors limit themselves to the electrostatic energy domains.

Both, mechanical and electric models of accelerometers give the input data for defining the object‐oriented model, based on Matlab‐Simulink platform, fulfilling the general demand of dynamic behaviour simulation of comb drive structure. The proposed by authors methodology could give valuable contribution to MEMS design methodology.

A new methodology has been successfully applied to calculation of levitation force in different geometries of comb drive. This methodology could be useful for multidisciplinary MEMS systems.

The purpose of this paper is to gain an in-depth understanding into the research progress, hot spots and future trends in smart gripping technology in the field of apparel smart manufacturing.

This work scrutinised the current research status of the five automatic grasping methods for garment fabrics including the pneumatic suction grasping, the electrostatic grasping, the intrusive grasping and the dexterous grasping. Specifically, the principles, characteristics, main devices and the impact on garment production were discussed.

In particular, soft finger of the dexterous grasping method has good flexibility and adaptability in the process of fabric grasping, which provides a new solution for garment production automation. Up to now, the reviewed method in general exhibit good grasping speed, high grasping stability and flat grasping process. However, in the face of complex fabric materials which are thin and flexible and do not return their original shapes when deformed in practical applications, the gripper for automatic fabric grasping need new technological breakthroughs in the positioning accuracy, grab efficiency and flexible grasping.

The outcomes offered an overview of the research status and future trends of the automatic grasping methods for garment fabrics in the field of apparel intelligent manufacturing. It could not only provide scholars with convenience in identifying research hot spots and building potential cooperation in the follow-up research but also assist beginners in searching core scholars and literature of great significance.

In this paper a modified numerical method for calculating the precipitation efficiency of wire‐duct electrostatic precipitators is reported. Variation of mobility for both ions and particles in space surrounding the energized wires is taken into consideration. This method is based on solving numerically the main set of equations, defining the ionized field with presence of dust particles. The precipitation efficiency of the electrostatic precipitators is determined for the cement industry. The effect of different geometrical parameters on the precipitation efficiency is also reported. The precipitation efficiency of the wire‐duct electrostatic precipitator as influenced by both the applied voltage and the gas flow speed is discussed in this paper. The present findings are correlated to the physics of electrical corona discharge.

To suggest a new revolutionary electrostatic linear engine.

Methods of the electrostatic physic are used for research.

Theory of this engine is developed and its possibilities researched.

This engine gives a big thrust (up 4 × 10⁵ N/m²), uses a high voltage electricity and light wires.

This engine can be used as a linear engine (accelerator), as a strong space launcher, as a high speed delivery system for space elevator, Earth‐Moon cable transport space, for an electrostatic levitation train, as a conventional high voltage rotating engine, as an electrostatic electric generator weapon (high speed gun), and so on. Theory of engine applications was developed and it shows powerful possibilities in space, transport and military industries. The projects are computed and show the good potential of the offered new concept.

Succeeds in proposing a new revolutionary electrostatic linear engine.

This paper aims to provide detailed information on the dynamic model and closed‐loop control theory for a resonant accelerometer based on electrostatic stiffness, which is important for the design of this type of resonant accelerometer.

After analysing the principles of the resonant accelerometer based on electrostatic stiffness, a dynamic model was built. According to the requirements of the closed‐loop control, the control equations based on phase‐locked technology were also built for the system. With the help of the averaging method, the system behaviour was analysed, and the equilibrium for the vibration amplitude was achieved.

The theoretical analysis and simulation show that integral gain is critical to system stability. When it is larger than the critical point, the system stable time is shorter, but the frequency‐tracking process fluctuates; if it is smaller than the critical point, the system stable time is longer, and the frequency‐tracking process stabilizes a resonant accelerometer was fabricated with a bulk‐silicon‐dissolved process. With the above conclusions, the accelerometer was driven and tested with a sensitivity of 47 Hz/g for a single vibration beam.

The dynamic model and the control theory for the resonant accelerometer based on electrostatic stiffness were presented in this paper. The simulation and experiment results agree well with the theoretical analysis.

The purpose of this paper is to present a hybrid numerical simulation approach for the calculation of potential and electric field distribution considering charge and dielectric constant.

Each numerical method has its own advantages and disadvantages. The idea is to overcome the disadvantages of the corresponding numerical method by coupling with other numerical methods. An augmented finite element method (FEM), linear FEM and boundary element method are used with an efficient coupling.

The simulation model of microstructured devices is not so simple. During the simulation various types of problems will occur. It is found that by using several numerical methods these problems can be overcome and the calculation can be performed efficiently.

The present approach can be applied in 2D cases. But, in 3D cases the calculation of augmented FEM in a spherical coordinate becomes quite elaborate.

The proposed hybrid numerical simulation approach can be applied for the simulation of the electrostatic force microscope (EFM) which is a very high‐resolution measuring tool in nanotechnology. This approach can be applied also to other micro‐electro‐mechanical systems.

Since the scanning process of the EFM is dynamic, it requires the updating of the FEM mesh in each calculation time step. In the present paper, the mesh updating is achieved by an arbitrary Lagrangian‐Eulerian (ALE) method. The proposed numerical approach can be applied for the simulation of the EFM including this remeshing algorithm ALE.

To predict the influence of inherent microfabrication and operating environmental influences on the performance of capacitive type sensors and actuators so that one can tune the performance and carry out more realistic designs.

When the sensors and actuators are micromachined or microfabricated, they are subjected to special problems that are characteristic to microdimensions. The important concerns are the influence of microfabrication process on the material properties and influence of operating environment on the system behavior. Hence, this paper proposed a way of quantifying and modeling the influence of inherent limitations of microfabrication and operating environment for the better design of micromachined capacitive type sensors and actuators. The methodology applies the modeling the variation of the elastic property of the system due to above influences through elastic stiffening and weakening concepts. The approach includes the application of boundary conditioning concept through Rayleigh energy method.

The microfabrication process and electrostatic field can alter significantly both static and dynamic behavior of the device. The performance of the device could also be tuned through these influences.

As the displacement of the sensors is expected to be small, linear approach is applied. The sensitivity, output range, operating limits and natural frequencies of the sensor can be easily controlled by varying the process and operating environmental influences.

Improved and more realistic design of microfabricated capacitive type sensors and actuators for many applications, such as, pressure sensors, microphones, microspeakers, etc.

A simple and easy way of modeling and quantifying the influence of process and operating environment was proposed for the betterment of design. The proposed design method can be applied for any micromachined or microfabricated capacitive type sensors and actuators so that varying sensitivities, output ranges and natural frequencies could be obtained. Over the last few years, newly emerging micro‐electro‐mechanical‐systems (MEMS) technology and micro‐fabrication techniques have gained popularity and importance in the miniaturization of a variety of sensors and actuators. The proposed technique is very useful in making the field of MEMS more matured as it attempts to model the problems that are unique to MEMS environment.

The purpose of this study is to focus on the preparation of macroporous adsorption resins (MARs) functionalized with carbazole and N-methylimidazole, and adsorption behaviors of (–)-epigallocatechin gallate (EGCG) and caffeine (CAF) on the functionalized MARs.

Based on the Friedel–Crafts and amination reactions, novel MARs functionalized with carbazole and N-methylimidazole were synthesized and characterized by the BET method. Accordingly, adsorption behaviors and structure-activity relationships for EGCG and CAF were studied in detail.

The results showed that pseudosecond-order kinetic model was provided with a better correlation for the adsorption of EGCG and CAF onto L-1 and L-2, and pseudofirst-order kinetic model was the most suitable model to illustrate the adsorption process for EGCG and CAF on L-3. The result indicated that Langmuir, Freundlich, Temkin–Pyzhev and Dubinin–Radushkevich isotherms all could better illustrate the adsorption processes of EGCG and CAF on L-1, L-2 and L-3.

This study provides theoretical guidance and technical support for the efficient separation and purification of EGCG and CAF from waste tea leaves by MARs on a large scale. In addition, the results showed that this novel MARs would provide useful help and be used in large-scale production of active ingredients from natural products in the industry and other fields.

Adsorption kinetic models such as pseudofirst-order, pseudosecond-order and intra-particle diffusion kinetic models, and adsorption isotherm models such as Langmuir, Freundlich, Temkin–Pyzhev and Dubinin–Radushkevich isotherms models were adopted to illustrate the adsorption mechanisms of EGCG and CAF. The main driving forces for MARs with no functional groups were pore sieving effects, p–p conjugation effects and hydrophobic interactions, and the other significant driving forces for MARs functionalized with carbazole and N-methylimidazole were electrostatic interactions, ion-dipole and hydrogen bonding interactions. This study might provide scientific references and useful help for large-scale separating and enriching active ingredients in natural products using the technology of MARs with special functional groups.