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EARLY in 1963, a project was initiated in co‐operation with an European airline with a purpose of starting development work for a new transducer for engine vibration monitoring. The low reliability of former pickups motivated this development work. In the course of the development, modern engine design requirements raised the need for the high temperature stability of these transducers. The development work was, therefore, based on the necessity to produce a vibration transducer with extreme high reliability, good interchangeability tolerance and useable up to approximately 600 deg. C. in practical flight operation. With regard to these requirements, a suitable technical approach seemed to be the use of the piezoelectric transducer technique, because seismic acceleration pickups working on the piezoelectric principle do not use moving parts, whereas displacement and velocity pickups, used so far, have at least one moving part, i.e. the inertial mass. Also the requirement for high temperature stability could be met by using modern crystal technology. The following chapters will expound some mechanical and crystallographic considerations in connection with such transducers, and furthermore describe some devices which are now being used in practical flight operation. Today, the concept of a piezoelectric, high temperature accelerometer with 2‐pole signal output has been commonly adopted in industrial production of transducers for airborne vibration monitoring.

The purpose of this study is to design a simple and cheap temperature transducer with frequency output with high measurement resolution in low temperature co-fired ceramic (LTCC) technology by using the distributed Resistance-Capacitance (RC) networks in high-pass filter configuration.

This paper presents the concept of elaboration of a transducer of temperature into frequency, its implementation in LTCC technology and test results. Construction and technological works are supported by a series of computer simulations of the process of indirect adjustment of the whole system.

The investigation results of the proposed and developed system have confirmed the correctness of the adopted concept, and the practical usefulness of an applied original method of indirect adjusting of the transducer.

The study contains practical and useful information about the principles of designing and manufacturing of the converters of the different physical quantities into frequency by using the elements with distributed parameters made in LTCC technology which was presented on the example of a temperature transducer.

The study presents the original solution of a simple transducer with the use of RC structures with distributed parameters made in LTCC technology and the idea of indirect adjustment of the elements to a desired value.

Analyses the effects of temperature on the behaviour of ultrasonic sensors applied to object recognition. Describes the measurement system employed, the environmental considerations of ultrasonic sensors and looks at the most commonly used parameters to analyse the echo form in the recognition process. Evaluates the performance of the parametric model of the ultrasonic echo signal with a comparative study of different ultrasonic transducers.

This paper aims to carry out a thermal-hydraulic simulation model for pump and hydraulic system to predict the temperature increasing and pump performance. Based on the model, how to alleviate the temperature is introduced. Besides, the optimization of piston is carried out.

This paper analyzes the heat generation in lubricating interfaces of the pump with energy conversion theory. The heat transfer inside the pump is analyzed with the control volume method. The simulation model is constructed in AMESim because of its operating friendly nature. The experiment is carried out to prove the validity and accuracy of the simulation model.

Temperature has less effect on the mechanical loss of pump. However, it has a great impact on volumetric efficiency. To reduce the temperature on the piston surface, the size of the piston should be optimized.

This paper fulfills a novel thermal-hydraulic model to evaluate the temperature of the pump. Based on the model, the performance of the pump is determined and optimization is carried out.

The purpose of this paper is to reveal the effect of starting time on hydro-viscous drive speed regulating start.

The modified transient Reynolds equation, thermal energy equation and temperature–viscosity equation were solved simultaneously by using finite element method. And then variations of the oil film load capacity, variations of temperature and variations of the torque generated by the oil film during the starting process were obtained.

The results show that during the starting process, both the oil film load capacity and the temperature show an upward trend, the torque increases during the beginning period and then decreases during the latter part of the starting process. When the starting time is less than 60 s, variations of the oil film load capacity and temperature show fluctuations, which decrease with the starting time. For any output speed, the corresponding oil film load capacity, temperature and torque decrease with the starting time, and the decreasing amplitude also decreases with the starting time.

This paper indicates that the starting time can be set to 60-90 s to obtain a perfect starting process. The simulation results are verified by the speed regulating start experiments. Research findings of this work provide theoretical basis for the design and practical application of the hydro-viscous drive equipments.

ENDEVCO UK has introduced a new microprocessor‐based instrument for conditioning and display of signals derived from vibration transducers on rotating machines.

A UK research team has developed a means of quantifying the performance of robot systems. Details of the design and results achieved with a PUMA 560 are described.

Evaluates the applicability of ultrasonic sensors in a welding environment and reports on experimental measurements carried out with a sensory head containing ultrasonic transducers with different frequencies. Analyses the effects on the sensors of factors such as noise, temperature and shielding gas flow and concludes by suggesting appropriate protective measures for the sensors for them to operate effectively in a welding environment.

Successful incorporation of transducers into measuring devices depends on choosing the type most suited to the task.

This paper is aimed at Engineers involved in production wire‐bonding processes and system maintenance. It traces the development of microbonding from its origins to the present day. Principles and techniques are examined and some approaches to fault diagnosis are explored.