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This paper aims to study a high-temperature (up to 200 °C) data acquisition and processing circuit for logging.

With the decrease in thermal resistance by system-in package technology and exquisite power consumption distribution design, the circuit worked well at high temperatures environment from both theoretical analysis and real experiments evaluation.

In thermal simulation, considering on board chips’ power consumption as additional heat source, the highest temperature point reached by all the chips in the circuit is only 211 °C at work temperature of 200 °C. In addition, the proposed circuit was validated by long time high-temperature experiments. The circuit showed good dynamic performance during a 4-h test in a 200-°C oven, and maintained a signal-to-noise ratio of 92.54 dB, a signal-to-noise and distortion ratio of 91.81 dB, a total harmonic distortion of −99.89 dB and a spurious free dynamic range of 100.28 dB.

The proposed circuit and methodology showed great potential for application in deep-well logging systems and other high-temperature situations.

This paper aims to investigate the usability of the nickel copper zinc ferrite with the composition Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 for the realization of high-temperature multilayer coils as discrete components and integrated, buried function units in low temperature cofired ceramics (LTCC).

LTCC tapes were cast and test components were produced as multilayer coils and as embedded coils in a dielectric tape. Different metallization pastes are compared. The properties of the components were measured at room temperature and higher temperature up to 250°C. The results are compared with simulation data.

The silver palladium paste revealed the highest inductance values within the study. The measured characteristics over a frequency range from 1 MHz to 100 MHz agree qualitatively with the measurements obtained from toroidal test samples. The inductance increases with increasing temperature and this influence is lower than 10%. The characteristic of embedded coils is comparable with this of multilayer components. The effective permeability of the ferrite material reaches values around 130.

The research results based on a limited number of experiments; therefore, the results should be verified considering higher sample sizes.

The results encourage the further investigation of the material Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 for the use as high-temperature ferrite for the design of multilayer coils with an operation frequency in the range of 5-10 MHz and operation temperatures up to 250°C.

It is demonstrated for the first time, that the material Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 is suitable for the realization of high-temperature multilayer coils and embedded coils in LTCC circuit carriers with high performance.

Gas‐cooled solar heat exchanger units (panels) are envisaged for installation in solar tower power plants. The thermal stresses arising in the panel in solar operation are high and are in part unique, so that design and development of this hot component has to rely on experimental studies. The present paper describes experimental studies done on a panel. For the tests a 3 MW hot‐gas test facility built primarily for the testing of hot components is used. Solar operating conditions are simulated on a panel prototype and the resulting thermal loads measured on critical panel components. Planning and optimizing of the test program as well as the evaluation of test results have been supported with finite element computing. The test results presented here show what stresses are exerted on the components by the solar‐specific operating conditions. Moreover, it is shown how rapidly changing unsteady thermal loads at high temperatures can be precisely detected and evaluated. In combination with efficient modern methods of calculation (e.g. finite element analysis) these results can be also be used to solve similar problems on other hot components.

The purpose of this paper is to obtain a single setting (optimal setting) of various input parameters of pack cementation process, i.e. halide salt activator, powder of master alloy and wt% of Y₂O₃ to obtain a single output characteristic as a whole namely resistance of hot corrosion for T91 steel.

The multi-criterion methodology based on Taguchi approach and utility concept has been used for optimization of the multiple performance characteristics namely hot corrosion rate K_P1, K_P2 and K_P3 for pack cementation coated T91 steel in chlorine and vanadium environment.

All the three pack cementation parameters, namely, halide salt activator, powder of master alloy and wt% of Y₂O₃ had a significant effect on the utility function based on analysis of variance for multiple performances. The percentage contribution of halide activator (1.54 percent), master alloy powder (4.66 percent) and wt% Y₂O₃ (93.79 percent). The results indicated the beneficial influence of yttrium on the chemical stability of the protective layer in presence of chlorine and vanadium environments. The optimal parameter settings obtained in this study is A2B2C1, i.e. halide salt activator (NaCl), powder of master alloy (92Cr-8Al) and 1wt% of Y₂O₃.

The outcome of this study shall be useful to explore the possible use of the developed coating for high temperature components. Unfortunately, the pack cementation was normally limited by the diffusion and reaction kinetics involved, which has a detrimental effect on the mechanical properties of work pieces. Therefore, reducing pack cementation temperature is required for widespread application of the pack coatings.

Pack coating at optimum conditions can be used for surface coating technologies to economically improve high temperature oxidation, corrosion resistance of components.

The multi-criterion methodology based on Taguchi approach and utility concept has been used for first time for parametric optimization of wt% Y₂O₃ modified chromium- aluminide coatings for T91 steel.

High‐density packaging devices have unique characteristics which make their assembly, test and repair very difficult. The only realistic method of rework is to replace the defective component with a new or re‐balled component. Although a wide range of rework techniques is available, degradation in assembly reliability may accompany the process. The formation of brittle secondary intermetallic compounds following CSP rework can adversely affect the mechanical properties of the joint, particularly when they make up a significant proportion of its thickness. Reports on the effects of different CSP rework techniques on intermetallic layer formation. Two PCB pad‐cleaning methods and three flux/paste deposition methods are investigated. The reworked joints are analysed using optical microscopy to determine the extent of intermetallic growth. Their quality is also assessed using shear strength testing prior to, and after, thermal ageing at 1008C to accelerate the growth of intermetallic compounds and evolution of the solder grain structure.

THE Structural Integrity Centre (SIC) had its origins in the 1970s when major integrity issues arose on the UKAEA's plant in service, eg weld cracking in the prototype fast reactors (PFR) steam generator units, and safety concerns led to a rigorous assessment of the integrity of the civil pressurised water reactors (PWR) pressure vessel (the Marshall committee report). In both cases engineers and scientists from various disciplines throughout the authority were involved in the consideration and resolution of these issues, and it was demonstrated that assurance of plant integrity could no longer be provided by the plant designer or operator alone.

The Airlite 71 headset has a clip in facility on a boom arm for the rapid interchange of microphones. This includes the Dyn‐A‐Mike microphone plus pre‐amplifier for the replacement of carbon microphones.

Tin‐lead solder has been the primary method for connecting electronic components to printed circuit boards since near the time of its inception. Over the last 60 years, solder has proven a viable assembly method over that time and there is a deep understanding of the technology won over years of practice. However, the European Union has banned the use of lead in electronic solder, based on the misguided assumption that lead in electronic solder represented a risk to human health. Aims to describe a new approach to manufacturing electronic assemblies without the use of solder.

The paper discusses how the new era of lead‐free solder has resulted in a host of new problems for the electronics industry, many of which had not been experienced when elemental lead was included in the solder alloy.

Electronics assembly technology literature is rife with articles and papers citing the problems or challenges of lead‐free assembly and proposing new or improved solutions or investigative tool to better unearth the problems of lead‐free. The new process has come to be known as the Occam process, named to honor the fourteenth century English philosopher and logician, William of Occam, whose rigorous thinking and arguments in favor of finding the simplest possible solution served as the inspiration and catalyst for the new approach.

The paper describes a new approach to manufacturing electronic assemblies without the use of solder.

This paper aims to study the feasibility of using machine learning in hot corrosion prediction of Inconel 617 alloy.

By examination of the experimental studies on hot corrosion of Inconel 617, a data set was built for machine learning models. Apart from the alloy composition, this paper included the condition of hot corrosion like time and temperature, and the composition of the saline medium as independent features, while the specific mass change is set as the target feature. In this paper, linear regression, random forest and XGBoost are used to predict the specific mass gain of Inconel 617.

XGBoost yields the coefficient of determination (R²) of 0.98, which was highest among models. Also, this model recorded the lowest value of mean absolute error (0.20). XGBoost had the best performance in predicting specific mass gain of the alloy in different times at temperature of 900°C. In sum, XGBoost shows highest accuracy in predicting specific mass gain for Inconel 617.

Using machine learning to predict hot corrosion in Inconel 617 marks a substantial progress in this domain and holds promise for simplifying the development and evaluation of novel materials featuring enhanced hot corrosion resilience.

This paper aims to present the design and experimental tests of an active circulating cooling system for the Experimental Advanced Superconducting Tokamak in-vessel inspection manipulator, which will help the current manipulator prototype to achieve a full-scale in-vessel high temperature environment compatibility.

The high-temperature effects and heat transfer conditions of the manipulator under in-vessel environment were analyzed. An active circulating cooling system was designed and implemented on the manipulator prototype. A simulative in-vessel inspection task in a high temperature environment of 100°C was carried out to evaluate the performance of the active circulating cooling system.

The proposed active circulating cooling system was proved effective in helping the manipulator prototype to achieve its basic in-vessel inspection capability in a high temperature environment. The active circulating cooling system performance can be further improved considering the cooling structure coefficient differences in different manipulator parts.

For the first time, the active circulating cooling system was implemented and tested on a full-scale of the in-vessel inspection manipulator. The experimental data of the temperature distribution inside the manipulator and the operating status of the circulating system were helpful to evaluate the current active circulating cooling system design and provided effective guidance for improving the overall system performance.