SiR Insulation for Outdoor Insulator

2017 ◽  
pp. 57-113
Keyword(s):  
Discharge Current ◽  
High Speed ◽  
Laboratory Tests ◽  
Electrical Strength ◽  
Surface Discharge ◽  
Contact Method ◽  
Light Weight ◽  
Hydrophobic Properties ◽  
Acoustic Characteristics ◽  
Accurate Evaluation

Silicone rubber (SiR) insulators were employed in power system due to its light weight, high electrical strength and excellent contamination performance. Much attention has been paid on the accurate evaluation of the insulator hydrophobicity. In this chapter, the acoustic characteristics of surface discharge were investigated to evaluate the hydrophobic properties of SiR insulator at different ageing degrees. The obtained results indicate that the acoustic characteristic of discharge is sensitive to the hydrophobic properties in the laboratory tests, which can be applied as a non-contact method for hydrophobicity evaluation of SiR insulator. Besides, the surface charge behaviors considering the hydrophobic properties of SiR insulator were discussed. The droplet experiment was carried out to investigate the maximum value, cumulative charge and energy eigenvector of discharge current. Finally, considering the strong airflow for SiR insulators employed in high-speed railway, the hydrophobic properties and corona discharge properties were investigated in this chapter.

Wear of Titanium and Titanium Alloys Under Conditions of Rolling Stress

1978 ◽  
Vol 100 (2) ◽  
pp. 199-207 ◽  
Author(s):  
H. Krause ◽  
J. Scholten
Keyword(s):  
Titanium Alloys ◽  
Weight Reduction ◽  
High Speed ◽  
Laboratory Tests ◽  
Total Weight ◽  
Wear Behaviour ◽  
Light Weight ◽  
High Speed Railway ◽  
Railway Traffic ◽  
Positive Results

One of the most important conditions necessary for high-speed railway traffic is a clear reduction of the unsprung masses. The fact that even with light-weight wheelsets, the steel tires still constitute over 50 percent of the total weight, shows that it is here, by utilizing the lightweight materials, that the most promising possibility of weight reduction lies. For this reason, the frictional and wear behaviour of various titanium alloys was investigated and compared with that of normal steels. From the positive results, it would appear worthwhile carrying out further investigations under practical conditions as an adequate assessment cannot be obtained on the basis of the laboratory tests alone.

Analysis of Fabric Shape Style Evaluation Method

2014 ◽  
Vol 1048 ◽  
pp. 173-177 ◽  
Author(s):  
Ying Mei Wang ◽  
Yan Mei Li ◽  
Wan Yue Hu
Keyword(s):  
Image Processing ◽  
High Speed ◽  
Evaluation Method ◽  
Contact Method ◽  
Ccd Cameras ◽  
Point Matching ◽  
Feature Point Matching ◽  
Motion Parameters ◽  
Measurement And Evaluation ◽  
Main Factor

Fabric shape style is one of the most important conditions in textile appearance evaluation, and also the main factor influences customer purchasing psychology. At first, the previous fabric shape style evaluation methods are classified and summarized, measurement and evaluation method discussed from tactic and dynamic aspects. Then, companied with computer vision principle, a non-contact method for measuring fabric shape style was put forward. In this method, two high-speed CCD cameras were used to capture fabric movement dynamically, fabric sequences image were obtained in this process. Used the image processing technology include pretreatment and feature point matching to get 3D motion parameters, it can provide data supports for shape style evaluation.

scholarly journals A High-Speed, Light-Weight Scalar Magnetometer Bird for km Scale UAV Magnetic Surveying: On Sensor Choice, Bird Design, and Quality of Output Data

2021 ◽  
Vol 13 (4) ◽  
pp. 649
Author(s):  
Arne Døssing ◽  
Eduardo Lima Simoes da Silva ◽  
Guillaume Martelet ◽  
Thorkild Maack Rasmussen ◽  
Eric Gloaguen ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Signal To Noise Ratio ◽  
Regional Scale ◽  
Weather Conditions ◽  
Light Weight ◽  
Output Data ◽  
Efficient Manner ◽  
Flexible System ◽  
Scalar Data

Magnetic surveying is a widely used and cost-efficient remote sensing method for the detection of subsurface structures at all scales. Traditionally, magnetic surveying has been conducted as ground or airborne surveys, which are cheap and provide large-scale consistent data coverage, respectively. However, ground surveys are often incomplete and slow, whereas airborne surveys suffer from being inflexible, expensive and characterized by a reduced signal-to-noise ratio, due to increased sensor-to-source distance. With the rise of reliable and affordable survey-grade Unmanned Aerial Vehicles (UAVs), and the developments of light-weight magnetometers, the shortcomings of traditional magnetic surveying systems may be bypassed by a carefully designed UAV-borne magnetometer system. Here, we present a study on the development and testing of a light-weight scalar field UAV-integrated magnetometer bird system (the CMAGTRES-S100). The idea behind the CMAGTRES-S100 is the need for a high-speed and flexible system that is easily transported in the field without a car, deployable in most terrain and weather conditions, and provides high-quality scalar data in an operationally efficient manner and at ranges comparable to sub-regional scale helicopter-borne magnetic surveys. We discuss various steps in the development, including (i) choice of sensor based on sensor specifications and sensor stability tests, (ii) design considerations of the bird, (iii) operational efficiency and flexibility and (iv) output data quality. The current CMAGTRES-S100 system weighs ∼5.9 kg (including the UAV) and has an optimal surveying speed of 50 km/h. The system was tested along a complex coastal setting in Brittany, France, targeting mafic dykes and fault contacts with magnetite infill and magnetite nuggets (skarns). A 2.0 × 0.3 km area was mapped with a 10 m line-spacing by four sub-surveys (due to regulatory restrictions). The sub-surveys were completed in 3.5 h, including >2 h for remobilisation and the safety clearance of the area. A noise-level of ±0.02 nT was obtained and several of the key geological structures were mapped by the system.

Biological control of Eutypa armeniacae. 4. Design and performance of an applicator for metered delivery of protective aerosols during pruning

1978 ◽  
Vol 18 (91) ◽  
pp. 287 ◽  
Author(s):  
MV Carter ◽  
LF Mullett
Keyword(s):  
Biological Control ◽  
Laboratory Tests ◽  
Field Tests ◽  
Piston Pump ◽  
Light Weight ◽  
Biological Matter ◽  
And Performance ◽  
Time Required ◽  
Aerosol Form ◽  
Three Components

The paper describes the development of a prototype applicator for delivery of protective mixtures, in aerosol form, to the wounded sapwood surfaces exposed during pruning. The equipment has three components : a 2 litre day-service tank, a light weight belt-mounted piston pump, and a modification of a standard pneumatic-powered pruning handgun. Laboratory tests of the applicator have proved its ability to deliver, repeatedly, a uniform dose of aerosol containing sufficient particulate chemical and/or biological matter to protect apricot sapwood from invasion by Eutypa armeniacae. Field tests of the equipment in two orchards demonstrated that from 90-100 per cent of wounds can be treated for the addition of less than 20 per cent to the time required to prune a tree. Over a period of three weeks' use no mechanical defects developed. Estimated volume of protective fluid required per day, treating up to 90 per cent of wounds, is less than two litres.

Suppression of Internal Damping-Induced Instability Using Adaptive Techniques

2007 ◽  
Author(s):  
Andra´s Simon ◽  
George Flowers
Keyword(s):  
Composite Materials ◽  
Simulation Modeling ◽  
High Speed ◽  
High Strength ◽  
Light Weight ◽  
Internal Damping ◽  
Modeling And Analysis ◽  
Rotor Systems ◽  
Rotor Spinning ◽  
High Speeds

Advanced rotor systems, for such applications as high-speed flywheel systems, consist (in a basic fashion) of a lightweight rotor spinning at relatively high speeds and supported by magnetic bearings. Composite materials are an extremely attractive choice for such rotor designs, offering high strength with light-weight. However, there are a number of issues that must be addressed for such efforts to be successful. Specific issues include imbalance control and active techniques to suppress internal damping-induced instability. A detailed description of the problem being considered and a strategy for solving it are presented. Simulation modeling and analysis results are presented and discussed to illustrate the method and demonstrate its effectiveness.

scholarly journals Performance and Internal Flow of a Dental Air Turbine Handpiece

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Yasuyuki Nishi ◽  
Hikaru Fushimi ◽  
Kazuo Shimomura ◽  
Takeshi Hasegawa
Keyword(s):  
Driving Force ◽  
High Speed ◽  
Performance Test ◽  
Internal Flow ◽  
Light Weight ◽  
Air Turbine ◽  
High Speed Rotation ◽  
Speed Rotation ◽  
Close Distance ◽  
Turbine Output

An air turbine handpiece is a dental abrasive device that rotates at high speed and uses compressed air as the driving force. It is characterized by its small size, light weight, and painless abrading due to its high-speed rotation, but its torque is small and noise level is high. Thus, to improve the performance of the air turbine handpiece, we conducted a performance test of an actual handpiece and a numerical analysis that modeled the whole handpiece; we also analyzed the internal flow of the handpiece. Results show that experimental and calculated values were consistent for a constant speed load method with the descending speed of 1 mm/min for torque and turbine output. When the tip of the blade was at the center of the nozzle, the torque was at its highest. This is likely because the jet from the nozzle entered the tip of the blade from a close distance that would not reduce the speed and exited along the blade.

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