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The problem of contamination in ceramic insulators was found to be frequent in power transmission lines and transformers. The key aim was to develop aquaphobic zirconium oxide (ZrO2) thin films using DC reactive magnetron sputtering over glass insulators to mitigate contamination problems. This was achieved by introducing O2 and Ar gas in the sputtering chamber, and three properties, namely, structural, optical, and aquaphobic, were inspected by changing the sputtering gas ratio (oxygen/argon). These properties were chosen based on comparison with the bulk ZrO2. These deposited ZrO2 samples were identified by X-ray diffractometer (XRD), atomic force microscopy (AFM), UV-Vis-NIR spectrophotometer, and contact angle goniometer (CAG). For all the samples, coatings were found to be limpid, clear, and aquaphobic. Coarseness (62.813 nm) and the contact angle made by water to the surface (107.45°) were found utmost as deposited at 0.25 oxygen/argon gas ratios. The transmittance and band gap were also found to be 90% and 5.33 eV, respectively, at this particular ratio.

Supplementary Material 1

Large bandgap insulators are considered promising for applications such as photocatalysts, dielectric resonators and interference filters. Based on synchrotron X-ray diffraction, diffuse reflectance measurement and density functional theory, we report the crystal structure, optical response, and electronic properties of the synthesized $d^0$ double perovskite Ba$_2$ScTaO$_6$. In contrast to earlier prediction, the electronic bandgap is found to be large, $\sim 4.66$ eV. The optical response is characterized by the presence of multiple exciton modes extending up to the visible range. A detailed investigation of the direct gap excitons based on the Elliot formula is presented. Density functional theory based investigation of the electronic properties within generalized gradient approximation severely underestimates the electronic gap. To reach a quantitative agreement, we consider different available flavors of the modified-Becke-Johnson exchange-correlation potential and discuss their effects on the electronic and optical properties., Comment: 12 pages, 6 figures

Directional control valves start, stop or change the direction of flow in compressed air applications. To understand the different applications of compressed air and how valves are used, one must first have knowledge of the kinds and types of valves used by industries. This paper studies local valve control of the electro-hydraulic system. The slow response of hydraulic control valve usually becomes the hold-up of whole system performance. Although fast valves (e.g. high-bandwidth servo-valves) are available, they are far more expensive than slow valves (e.g. proportional directional control valves). To improve the performance of proportional directional control valves, three different types of controllers are synthesized. Firstly, based on the pole zero cancellation technique, an open loop compensator is designed which requires the accurate valve dynamic model information; Secondly, a full state feedback adaptive robust controller (ARC) is synthesized, which effectively takes into account the effect of parametric uncertainties and uncertain nonlinearities such as friction force and flow force. Finally, an output feedback ARC controller is synthesized to address the problem of un measurable states. Keywords: valve, hydraulic device, Simulink.

The hydrostatic transmission energy-saving system is proposed in this paper. The efficiency of the primary power source improves by system. The system is energy regenerative, highly efficient even under partial load conditions. It can work in either a flow or pressure coupling configuration allowing it to avoid the disadvantages of each configuration. The displacement variation in the secondary unit was reduced, increasing the uses of several types of hydraulic pump/motors. The proposed system was modeled based on its physical attributes. A hierarchal control system was implemented and focused on the design of an adaptive fuzzy sliding mode control for speed control of the secondary unit. The energy utilization and the influences on the energy-recovery potential of the system were analyzed.Keywords-Hydrostatic drive, energy saving system, Regenerative systems

In this paper, a new hydraulic energy-regenerative model was offered from its application through modelling to its control. The model was constructed on a closed-loop hydrostatic transmission and used a hydraulic accumulator as the energy storage system invented in a new configuration to recover the kinetic energy without any return of the fluid flow. The displacement deviation in the secondary unit was reduced, increasing the uses of several types of hydraulic motor/pumps. The proposed system was modelled based on its physical features. The energy consumption and the influences on the energy-recovery potential of the system were analyzed. Simulation and experiments were performed to evaluate the validity of the employed mathematical model and the effectiveness of the control system. Keywords: Hydraulic accumulator, Hydraulic system, Energy recovery.

Environmental and energy issues demand the construction equipment industry to develop more efficient and energy saving machines as they have done to the automotive industry in the last decade. This energy of traditional excavator is lost in the form of heat energy. Heavy earth moving equipments such as excavators, loaders and forklift trucks have unique power train mechanism, thus the focus on important issues like efficiency improvement or energy savings holds great value. Hence, the need of the hour is to develop machinery which can match the necessities and challenges of the ever evolving industry in terms of energy saving management. In this context, hybrid excavators have been ushered in currently. Here system translates the arm/boom/buck’s potential energy into electrical energy and then the electrical energy is stored in a storage device. It develops a set of energy management strategy to make the recoverable energy usage efficiently. The advancements in the field of heavy machineries holds key in future of hybrid excavators. Keywords-hybrid excavator; potential energy recovery; arm; energy saving

Nowadays with the high fuel costs, the stress for energy saving and green emission of construction machineries, while not sacrifice of the operating performance, safety and dependableness, particularly for hydraulic excavators (HYEXs), are extremely exaggerated. As a result, electro-hydraulic actuators (EHA), that is promoted and with success applied to industry, is recently introduced to HYEXs. The aim of this paper is to propose a new style of excavator - electrical excavator (ELEX) - with energy saving capability using the EHAs. Each of the hybrid actuators is driven by an electrical motor/generator for retrieving a potential energy or a kinetic energy at the time of lowering or slewing stoppage of the excavator. An excavator having a hybrid boom system (HBS) is analyzed. Finally, operating efficiency and energy consumption of the projected excavator area unit are clearly studied. Keywords: Hydraulic excavator; electric excavator; electro-hydraulic actuator; control

A Hydraulic circuit is a group of components such as pumps, actuators, and control valves so arranged that they will perform a useful task. When analyzing or designing a hydraulic circuit, the following three important considerations must be taken into account.Safety of operation,Performance of desired function, Efficiency of operation.It is very important for the fluid power ( Hydraulics and Pneumatics ) designer to have a working knowledge of components and how they operate in a circuit. Hydraulic circuits are developed through the use of graphical symbols for all components. Keywords: damper,hydraulic circuit

This paper focuses on the recent advancements made in hydraulic motor. Various parameters of hydraulic motors are studied and their performance with respect to the parameters is studied. nonlinear dynamics model, Gear motor, swash plate motor, radial piston hydraulic motor etc have been examined. Fault diagnosis, dynamic vibration, frictional analysis and speed variation are some of the issues which are being discussed in the paper. The performance results showed that the amplitude of vibration increased with the increase of output torque of the water hydraulic motor and the hydraulic motor with planetary gear train has the advantages of large unit volume displacement and small flow rate fluctuation ratio. Some measures were proposed to improve the low-speed stability of the hydraulic motor. Keywords-hydraulic motor, nonlinear dynamics, hydraulic spring

This paper represents a MEMS based gyroscope to measure orientation. Silicon-micro-machined gyro is fabricated on the basis of resonators and they use vibrating mechanical element to sense rotation. The vibratory measurement can be done by measuring the change in capacitance with respect to the voltage or force applied in particular axis. Here MEMS based gyroscope has been designed from Lame mode resonator which is a square plate. The additional benefits by using the gyroscope are lower sensor cost, power consumption, more robustness, higher shock resistance. In this paper, also sensitivity of the geometry and change of capacitance has been shown. Index Terms –Coriolis Force, Gyroscope, MEMS.

The North Indian Ocean exhibits profound impact of variation in lower tropospheric winds. In the present study climatological monthly winds are used to force a nonlinear reduced gravity model of the North Indian Ocean to simulate climatological surface circulation and sea level anomaly for all 12 months of the year. The sea level anomalies agree reasonably well with satellite altimeter derived sea level anomalies. The model successfully simulates the varying eddy structure and current pattern of the North Indian Ocean. Finally, the kinetic energy variation in the North Indian Ocean with special reference to equatorial region and the boundaries is analyzed in detail.