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To examine the impact of oxide and oxide alternative processes on signal loss in commercial RF applications.

Stripline conductors were formed using traditional oxide, oxide dissolution/reduction, and oxide alternative processes. Conductor geometry was measured and surface topography was characterized. Effective dielectric constants and characteristic impedance for each system was determined. Finally, line loss for each treatment and rework condition was charted to nearly 20 GHz. Electrical measurements were performed by taking S‐parameter measurements through 20 GHz using an agilent vector network analyzer (VNA).

The methods employed were sufficient to statistically characterize the increased loss associated with thick oxides and high‐microetch oxide alternatives. Lower etch oxide alternatives yielded benefits for signal integrity. Of importance, rework procedures gave unacceptable increases in line loss. Overall, however, the loss due to innerlayer bonding processes was not of sufficient magnitude to elevate oxides as a primary contributor to conductor loss. For the relative simple, high production system employing epoxy substrate, oxide loss was found to be far less than substrate effects, imaging quality, and foil treatment.

Electrical engineers and printed circuit board (PCB) designers strive to focus their efforts on improving the PCB processes leading to maximum conductor loss in the electronic system. This work shows that oxide treatments are not a primary factor in affecting loss. Significant improvements in signal integrity may be achieved, however, with the use of low‐etch oxide alternatives and with restrictions on oxide rework. In addition, this paper allowed for new interpretations of VNA data for better modeling of PCB system data using non‐classical analysis.

The purpose of this paper is to reduce the artifacts in fast Bayesian reconstruction images in electrical tomography. This is in particular important with respect to object detection in electrical tomography applications.

The authors suggest to apply the Box-Cox transformation in Bayesian linear minimum mean square error (BMMSE) reconstruction to better accommodate the non-linear relation between the capacitance matrix and the permittivity distribution. The authors compare the results of the original algorithm with the modified algorithm and with the ground truth in both, simulation and experiments.

The results show a reduction of 50 percent of the mean square error caused by artifacts in low permittivity regions. Furthermore, the algorithm does not increase the computational complexity significantly such that the hard real time constraints can still be met. The authors demonstrate that the algorithm also works with limited observations angles. This allows for object detection in real time, e.g., in robot collision avoidance.

This paper shows that the extension of BMMSE by applying the Box-Cox transformation leads to a significant improvement of the quality of the reconstruction image while hard real time constraints are still met.

The purpose of this paper is to present the effect of the aging at 200°C on creep and hardening behavior of hardenable 6101 aluminum alloy manufactured by an industrial wiredrawing process used for construction of self-supporting overhead aerial power line conductors.

The creep tests were carried out under applied constant stress 100 MPa and constant temperature 150°C. Hardness measurements were also used to investigate the mechanical behavior of the aged alloy. Micrographs of the fractured wires by creep tests were performed by scanning electron microscope. Electrical resistivity of the aged alloy was measured at different time of the aging treatment.

The authors have found the relationship between the precipitation sequence, the mechanical properties and the electrical resistivity of aged 6101 aluminum alloy.

The optimum properties were also deduced.

The purpose of this paper is to study a multiphase-flow instrumentation for film thickness measurement, especially impedance-based, not only for gas–liquid flow but also for mixtures of immiscible and more viscous substances such as oil and water. Conductance and capacitive planar sensors were compared to select the most suitable option for oil – water dispersed flow.

A study of techniques for measurement of film thickness in oil – water pipe flow is presented. In the first part, some measurement techniques used for the investigation of multiphase flows are described, with their advantages and disadvantages. Next, examinations of conductive and capacitive techniques with planar sensors are presented.

Film thickness measurement techniques for oil–water flow are scanty in the literature. Some techniques have been used in studies of annular flow (gas–liquid and liquid–liquid flows), but applications in other flow patterns were not encountered. The methods based on conductive or capacitive measurements and planar sensor are promising solutions for measuring time-averaged film thicknesses in oil–water flows. A capacitive system may be more appropriate for oil–water flows.

This paper provides a review of film thickness measurements in pipes. There are many reviews on gas – liquid flow measurement but not many about liquid – liquid flow.

This study aims to address the issue of high-precision measurement of AC electric field. An electro-optical sensor with high sensitivity is proposed for this purpose.

The proposed sensor combines electromagnetic induction and fiber Bragg grating (FBG) sensing techniques. It is composed of a sensing probe, a piece or stack of piezoelectric ceramics (PZT) and an FBG. A signal processing circuit is designed to rectify and amplify the induced voltage. The processed signal is applied to the PZT and the deformation of PZT is detected by FBG. Theoretical calculation and simulation are conducted to verify the working principle of the probe. The sensor prototype is fabricated and its performance is tested.

The results of this study show that the sensor has good linearity and repeatability. The sensor sensitivity is 0.061 pm/Vm⁻¹ in the range from 250 to 17,500 V/m, enabling a measurement resolution of electric field strength of 16.3 V/m. The PZT stack is used to enhance the sensor sensitivity and the resolution can be improved up to 3.15 V/m.

A flexure hinge lever mechanism is used to amplify the deformation of PZT for further enhancement of sensitivity. The results show that the proposed sensor has high sensitivity and can be used for the accurate measurement of an electric field. The proposed sensor could have potential use for electric field measurement in the power industry.

In the second edition of Greenwood's “Public Libraries,” 1887, p. 137, there is a description of the Dent Indicator, from which it may be gathered that such an indicator was actually constructed. The inventor, however, is of opinion that his idea never got so far as realization in material form, though there can be hardly any doubt that Mr. Dent's indicator is the first to combine indicating with charging, and that it suggested several succeeding devices. His account of it is interesting, as it mentions the existence of an early form of card indicator which has since been reinvented in various styles. “A certain Mr. Christie, Librarian of the Constitution Hill Branch Library (Birmingham), about 1868, constructed a small rack with cards bearing the titles of a selection of the books in history, science, &c, open to the public, and the presence of one of these tickets in the rack indicated that the book was ‘in.’ If anyone wished to take one of the books thus shown, he lifted the ticket out of the rack (there was no glass in front) and handed it to the attendant who put it in a box till the book came back, and then replaced it almost anywhere in the rack. This gave me an idea that the cumberous system of day‐book, posting‐book, and constant piles of books to be marked off as returned might be done away with, if tickets in a rack representing every number in the library were substituted for book‐entry, &c.” Mr. Dent's improvement upon this idea consisted in the provision of a series of numbered shelves in columns, with spaces between to take the borrowers' cards when the books were out. The back of the borrower's card was to be ruled to allow of numbers and dates being pencilled thereon, and, of course, the presence of a borrower's card under a number indicated a book “ out.”

There are demands from the industry to have a modern application of Electrical Capacitance Tomography (ECT) system which is mobile and agile. One of the factors why such system is needed in the industry is because of the requirement to install the measurement sensors in a hostile and harsh environment which demands a special kind of ECT system. This paper will discuss the features of mobile or portable ECT which is more practical to be implemented in the harsh environment. Besides, the implementation of cloud computing and wireless technology in the portable ECT systems is also discussed. This review outlines some key features of portable or in another word mobile ECT as a complete system.

There are demands from the industry to have a modern application of ECT system which is mobile and agile. One of the factors why such system is needed in the industry is due to the requirement to install the measurement sensors in hostile and harsh environment which demands a special kind of ECT systems. This paper will discuss the features of mobile or portable ECT which is more practical to be implemented in the harsh environment. Besides, the implementation of cloud computing and wireless technology in the portable ECT systems is also being discussed. This review outlines some key features of portable or in another word mobile ECT as a complete system.

This review outlines some key features of portable or in another word mobile ECT as a complete system. A lot of improvement can be done to realize a reliable and stable ECT system. It is seems that in the near future, machine to machine communication will become the main stream.

This paper fulfils an identified need to study improvement that can be done to develop a portable ECT system which is reliable and stable. Besides, the implementation of cloud computing and wireless technology in the portable ECT systems is also discussed.

Non‐planarity of assemblies and co‐planarity variation effects on anisotropic conductive adhesive (ACA) assemblies have been a concern for ACA users since the materials are first devised. The primary objective of this paper is to introduce a new experimental method for studying co‐planarity variation effects on ACA assemblies.

The approach simulates non‐planarity through deliberate chip rotation during the ACA bonding process, thereby locking different levels of co‐planarity variation into ACA test assemblies. Scanning electron microscope (SEM) analysis and electrical joint resistance measurement using the four wire resistance (FWR) method are used to mechanically and electrically examine the connection quality of the ACA assemblies bonded with non‐planar joints, for which the chip and substrate patterns are specially designed to allow joint resistance measurement using the FWR method.

Typical experiments and their results are presented and analysed. The bond thickness differences between the SEM measurements and calculations indicate that the real rotations are smaller than those predicted by the calculations. The typical experimental results show that the joint resistance reduces as the deformation increases until reaching a relatively stable value after a certain deformation degree.

The average joint resistances in the rotated samples are all bigger than those measured in the un‐rotated samples. This raises the question as to whether the joint resistances of ACA assemblies are more significantly affected by other affects of non‐planarity than just by its effect on bond thickness. However, before this can be confirmed, more research must be done to check if this behaviour happens for different bonding forces.

This paper reports a novel and simple experiment that can be used to examine the effects of co‐planarity variation on the electrical performance of ACA assemblies, by creating different bond thicknesses that are normally difficult to achieve by changing the bonding pressure, since ACA bond thicknesses are not linearly related to the bonding force. The merit of the technique is that there is no need to manufacture chip bumps and substrate pads with different geometries, or to control the bond pressure, to achieve bond thickness variation in ACA assemblies.

In the majority of devices for measuring the resistance of wires or cables, the supplying voltage is applied via some clamping arrangement. Thus, current enters the bundle of conductors through the side surface of the outside wire. The purpose of this project was to establish the distance from the supplying point after which the current may be considered to be uniform and normal to the cable cross‐section.

When current passes from one wire to another, the crucial parameter is the resistance of the contact region. The paper presents a method by which this region can be identified and relevant resistance measured. A comprehensive simulation was conducted for different types of wires and cables to assess the influence of design parameters on the current distribution and uniformity.

The distance from the current entry point (the clamps) to the position where current density may be considered uniform has been established. This has facilitated estimating recommended positions of voltage taps with reference to current taps.

The look‐up tables and graphs allow adjustments to the position of the taps and/or correction of the measured results.

The original contribution of this paper is in the way the contact region is identified where current passes from one wire to another. Original relationships have been proposed showing the relationship between contact resistance and the design parameters of the cable and mechanical stress.

Although, numerous optimization algorithms have been devoted to construct an electrical ladder network model (ELNM), they suffer from some frail points such as insufficient accuracy as well as the majority of them are unconstrained, which result in optimal solutions that violate certain security operational constraints. For this purpose, this paper aims to propose a flexible-constraint coyote optimization algorithm; the novelty lies in these points: penalty function is introduced in the objective function to discard any unfeasible solution, an advanced constraint handling technique and empirical relationship between the physical estimated parameters and their natural frequencies.

Frequency response analysis (FRA) is very significant for transformer winding diagnosis. Interpreting results of a transformer winding FRA is quite challenging. This paper proposes a new methodology to synthesize a nearly unique ELNM physically and electrically coupled for power transformer winding, basing on K-means and metaheuristic algorithm. To this end, the K-means method is used to cluster the setting of control variables, including the self-mutual inductances/capacitances, and the resistances parameters. Afterward, metaheuristic algorithm is applied to determine the cluster centers with high precision and efficiency.

FRA is performed on a power transformer winding model. Basing on the proposed methodology, the prior knowledge in selecting the initial guess and search space is avoided and the global solution is ensured. The performance of the abovementioned methodology is compared using evaluation expressions to verify its feasibility and accuracy.

The proposed method could be generalized for diagnosis of faults in power transformer winding.