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This research aims to determine the flashover voltage on the surface of porcelain insulators on 150 kV transmission lines located in Payakumbuh, where the insulators are contaminated with dust and moss due to the effects of temperature and humidity. The experiment is carried out with only up to seven insulator plates due to the limitations of the available apparatus. For the further testing, a trend analysis is applied. According to the experimental results, a rise in temperature around the insulator will increase the flashover voltage value and accelerate the potential for a flashover event. This happens because high temperatures can reduce the insulator's dielectric strength and insulation resistance and increase the risk of flashover. The dielectric strength values decreased with an average decrease of 44.62% per insulator plate for dusty insulators and 45.08% for each plate for mossy insulators. The results aim to minimize flashover on transmission lines in hilly areas with relatively high contamination. [ABSTRACT FROM AUTHOR]

Base isolation has been used as one of the most wildly accepted seismic protection systems that should significantly separate a superstructure from substructure on which it is resting on a shaking ground, there by sustainably saving entire structures against earthquake forces as well as inside non-structural failures. The main purpose of earthquake engineering is to design the structure in such a way that the damage in the structures and its other components during an earthquake is minimized. In the present study lead rubber base isolator (LRB) has been designed for a general low rise building. The building is then analyzed with ETABS software. The comparison has been made between the fixed base building and base isolated building to check the performance of the base isolated building. The seismic responses with respect to base shears and inter-story drifts have been compared before and after the installation of LRB isolation systems in the framed building. The main function of the LRB isolator is to extend the time period of structural vibration by increasing lateral flexibility in the framed structure, and ground accelerations transferred into the superstructure can dramatically decrease. [ABSTRACT FROM AUTHOR]

For future pharmaceutical personalized mass production, highly flexible aseptic automation solutions are needed such as 6-axis robot systems well known from car manufacturing lines. Up to date, most robots are not suitable for aseptic production due to the lack of hygienic design in regards to cleanability, decontamination and material selection. With one robot manufacturer we designed an aseptic robotic solution right from the initial idea in order to fulfil the required cleanliness level for sterile manufacturing processes described in the Good Manufacturing Practice guidelines (GMP). Finally, the performance of the robot is validated using standardized test scenarios. [ABSTRACT FROM AUTHOR]

The recognition method of equipment source parameters was present. In the case of separately acting by equipment unbalance exciting force and combined acting by unbalanced exciting force and unbalanced exciting moment, multi-dimensional coupled vibration model of 'equipment-isolator-base' were established. Based on Kirchhoff theory, it was assumed that the equipment source parameters (equipment equivalent exciting force and equivalent mass) were not affected by the external parameters of base and isolator. According to carrying out multiple sets of equipment bench test under different isolator, and using linear regression method, the equipment source parameters (equipment equivalent exciting force and equivalent mass) were recognized. Then, calculating equipment machine feet acceleration, equipment exciting loads were obtained, which can be as input loads for acoustic prediction of ship. In order to verify the validity of the recognition method of equipment source parameters, equipment bench test were developed. [ABSTRACT FROM AUTHOR]

Part 1 (Bafna, S. S., "The Effect of Temperature on the Tear Behavior of Various Elastomers," J. Test. Evai, Vol. 42, No. 3,2014, pp. 1-10) of this series discussed the tear behavior per ASTM D624-00 Type B (propagation) and Type C (initiation) for commercial sealing grade butyl, ethylene propylene diamine (EPDM), fluorosilicone (FS), and two fluorocarbon elastomers. Part 2 provides additional insight based on application considerations. The behavior of polychloroprene intended for shock and vibration isolation applications is compared to that of silicone and other elastomers intended for sealing applications (such as O-rings). The trend of tear strength for propagation being higher than or equal to (within measurement error) that for initiation is confirmed. This is shown to be an artifact of the difference in the ASTM D624-00 test specimen geometries. Propagation tear strength/energy values reported in literature are from the "trouser" tear (ASTM D624 Type-Tor modification thereof) test, which leads to lower values than Type B. While Type-T is closer in deformation mode to pure tear, Types B and C more closely simulate tear damage in actual hardware. The polychloroprene grade tested is processed using transfer molding and has a much lower viscosity in the uncured state. After cure, its tensile strength is lower than that of all compression molding grades and its tensile elongation is the highest. However, its tear strength is higher than that of the silicone or FS grades tested, consistent with its application requirements. At the higher temperatures, the polychloroprene tear strength is higher than that of all the compression molding grades. A higher level of filler (as manifested by a high specific gravity), along with strain induced crystallization, helps explain this retention of tear properties with temperature. The tear strain at break generally increases with temperature but, if temperature is sufficiently above the glass transition temperature, then the tear strain actually decreases with temperature and thus non-monotonic behavior is observed. The poor tear properties of silicones and FS are confirmed. [ABSTRACT FROM AUTHOR]

In geophysical survey system, a Time Domain Electro-Magnetic (TDEM) technique is used to detect the presence of uranium in the earth crust. For heliborne survey, certain equipments, such as power converter and data acquisition system are installed on a helicopter. The power converter is responsible for the generation of high current pulses to feed the transmitter for setting up the required electromagnetic field. The power converter consists of a free running inverter, which sits over a DC-DC converter. Data acquisition system acquires data from various sensors for further processing and interpretation. Data acquisition system consists of a highly vibration sensitive onboard computer (IDAN boxes) rigidly mounted over a plate inside the data acquisition system enclosure. Since the power converter and data acquisition system are installed on the floor inside the surveying helicopter, it is mandatory to qualify these equipments for vibration & shock as per MIL standard before onboard installation. To evaluate the structural integrity of power converter and data acquisition system under various loading conditions of vibration and shock, a preliminary estimation of stresses and deflections was made by hand calculations and then, finite element analysis has been performed to optimize the design. Modal analysis has been performed to estimate the natural frequencies of power converter. Since the natural frequencies of the power converter were within the disturbing frequency range (i.e., 10 to 84 Hz), thickness of converter base plate and inverter base plate has been increased to avoid resonance. Since the data acquisition system consists of a highly vibration sensitive onboard computer, it has been proposed to mount it on isolators to minimize the vibration. To evaluate the structural integrity of data acquisition system under various loading conditions, finite element analysis has been performed. This paper presents the methodology adopted for design and analysis of the equipments for the specified input of vibration and shock. [ABSTRACT FROM AUTHOR]

In geophysical survey system, a Time Domain Electro-Magnetic (TDEM) technique is used to detect the presence of uranium in the earth crust. For heliborne survey, certain equipments, such as power converter and data acquisition system are installed on a helicopter. The power converter is responsible for the generation of high current pulses to feed the transmitter for setting up the required electromagnetic field. The power converter consists of a free running inverter, which sits over a DC-DC converter. Data acquisition system acquires data from various sensors for further processing and interpretation. Data acquisition system consists of a highly vibration sensitive onboard computer (IDAN boxes) rigidly mounted over a plate inside the data acquisition system enclosure. Since the power converter and data acquisition system are installed on the floor inside the surveying helicopter, it is mandatory to qualify these equipments for vibration & shock as per MIL standard before onboard installation. To evaluate the structural integrity of power converter and data acquisition system under various loading conditions of vibration and shock, a preliminary estimation of stresses and deflections was made by hand calculations and then, finite element analysis has been performed to optimize the design. Modal analysis has been performed to estimate the natural frequencies of power converter. Since the natural frequencies of the power converter were within the disturbing frequency range (i.e., 10 to 84 Hz), thickness of converter base plate and inverter base plate has been increased to avoid resonance. Since the data acquisition system consists of a highly vibration sensitive onboard computer, it has been proposed to mount it on isolators to minimize the vibration. To evaluate the structural integrity of data acquisition system under various loading conditions, finite element analysis has been performed. This paper presents the methodology adopted for design and analysis of the equipments for the specified input of vibration and shock. [ABSTRACT FROM AUTHOR]

Because of high vibration amplitude, large frequency bandwidth, and vibration with randomness in the mechanical environment of space launch, the improvement of safe factor is of high significance for the special high reliability requirement of space launch, especially for that of the whole-spacecraft isolator. In this paper, the equal strength beam theory is first introduced and the corresponding mechanical model is established for the whole-spacecraft isolator. First, in summing up the domestic and foreign whole-spacecraft isolators' structural characteristics, we established a statically indeterminate composite beam model. Then, based on the small deformation assumption, Mohr theorem and equal strength beam theory, the mechanical model between the isolator's structural parameters and performance parameters is developed. The design method based on equal strength is derived after the explicit non-uniform strength mechanical model has been given. The proposed method can directly computes the isolator's performance parameters by structural parameters, and can design the equal strength isolator with needed safe factor. Finally, two kinds of isolators have been designed and analyzed. The results show that the stress distributes much more uniformly in the isolator's bracket and the safe factor can be improved significantly. [ABSTRACT FROM AUTHOR]

The test of nonlinear dynamic characteristics of rubber isolator has been conducted on the electrodynamic shaker, and the experimental signals have been processed through the FFT and IFFT. The dynamic model of rubber isolator was established and the effectiveness of parameter identification was validated for single load condition via both Runge-Kutta method and the curve reconstruction method. Thus the parameters of all load conditions were identified by the model, and the stiffness and damping of rubber isolator were obtained under different load conditions. The complex surface relationship between stiffness, damping and amplitude, frequency was discovered through analyzing the identified parameters. The identified results indicate that the dynamic characteristics can not be depicted by the simple curves under large deformation situation. [ABSTRACT FROM AUTHOR]

• Waveguide structure supporting acoustic spoof plasmon polaritons perturbed by a defect. • Controllable transmission with uniform phase distribution and steep narrowband response. • Potential applications include advanced filters, isolators, and sensor technology. We study a waveguide structure supporting acoustic spoof plasmon polaritons (aSSPPs) perturbed by a defect, whose specifically tailored geometry enables controllable transmission characterized by a uniform phase distribution and very steep narrowband response. The structure is analyzed using transmission-line theory and numerical simulations, providing evidence for its use in advanced filters, isolators and sensor technology. In order to demonstrate the applicability of the aSSPP waveguide with defect, two selective narrowband filter designs are discussed and explored. Furthermore, we propose an acoustic isolator that exploits steady fluid flow to break reciprocity and provide large isolation in a narrowband region. We also propose a sensor for liquid analytes, in which the grooves of the aSSPP waveguide serve as microfluidic channels, while the sensing principle is based on the spectral shift of the transmission peak for different mixtures of water and glycerol. The sensor shows a good sensitivity and fast response, with a potential for further development for applications in water quality monitoring. [ABSTRACT FROM AUTHOR]