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This paper aims to present a new wireless power transfer technique using capacitive coupling. The capacitive power transfer (CPT) system has been introduced as an attractive alternative to the traditional inductive coupling method. The CPT offers benefits such as simple topology, fewer components, better electromagnetic interference (EMI) performance and robustness to surrounding metallic elements.

A class-E inverter together with and without inductor capacitor (LC) matching circuit has been utilised in this work because of its ability to perform the DC-to-AC inversion efficiently with significant reduction in switching losses. The validity of the proposed concept has been verified by conducting a laboratory experiment of the CPT system.

The performances for both systems are analysed and evaluated. A 9.7 W output power is generated through a combined interface [printed circuit board (PCB) plate] capacitance of 2.82 nF at an operating frequency of 1 MHz, with 97 per cent efficiency for 0.25 mm coupling gap distance.

An efficient CPT system with class-E LC matching topology is proposed in this paper. With this topology, the zero-voltage switching can be achieved even if the load is different by properly designing the LC matching transformation circuit.

The purpose of this paper is to investigate the temperature reliability for a parallel high-efficiency class-E power amplifier (PA).

To explore the relationship between temperature and direct current (DC) characteristics, output power, S parameters and efficiency of the PA quantitatively, a series of reliability experiments have been designed and conducted to study the temperature reliability for this PA.

From the results, the prominent performance degradation even failure is found during the testing. Furthermore, the thermal shock test can cause permanent failure, which is a great threat for PA.

Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the stage of PA design.

All these can provide important guidance for the reliability design of PA.

All these can give some important guidance for PA application.

In addition, PA is usually designed according to the electrical properties at the room temperature. From the results above, it can be concluded that it may be unable to satisfy the performance requirement at high temperature. In turn, if it is designed according to the electrical properties at low temperature, the transistor often works in the super-saturated state, the reliability of PA will become the new problem. Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the design.

The purpose of this paper is to develop a model of the inductive link for implantable systems. The model is suitable for a cochlear implant in which a lateral misalignment and distance coil can be up to 16 mm.

The description of the generation of implantable systems' high‐power, such as a cochlear implant, are powered by transcutaneous inductive power links formed by two coils: the first is a printed spiral coil used in the receiver device and the second is a solenoid coil used in the emitter device. Optimizing the power efficiency of the wireless link is imperative to minimize the size of the external energy source, heating dissipation in the tissue, and interference with other devices. The authors have outlined the theoretical foundation of optimal power transmission efficiency in an inductive link, and combined it with semi‐empirical models to predict parasitic components. The power amplifier itself is a class‐E amplifier optimized in both output voltage and efficiency, and bears an excellent tolerance to misalignments.

Two Spice‐based electrical models of the coils are achieved. The technique employed during the work is based on polynomial interpolation of the mutual inductance in which coil misalignments are considered as variables. On the other hand, a voltage regulator is studied and simulated by Cadence Analog Artist in the AMS 0.35 μm CMOS technology.

This paper provides a novel and useful method for transmitting power for an implantable system via an inductive link. The procedure of the authors' design is achieved at 10 MHz and the power transmission efficiency is 35 percent, whatever the longitudinal misalignment (up to 16 mm) between both coils.

The paper presents the simplified model of the Class E inverter in which the MOSFET transistor is based on the piecewise‐linear (PWL) model. The model does not contain inductances. The PWL description makes it possible to obtain the model in the form of general closed formulae. The general formulae have been obtained by means of MATHCAD and verified with the IsSPICE^® simulator. The analysis of MOSFET switching performance in the active region at the constant load current is delivered. The work is a successive step in the systematic research of the Class E inverter as a supplying source in high frequency levitation heating/melting systems. The equivalent RL parameters of the load in such systems vary across a relatively wide range.

Five points separate the best from the rest.

This paper aims to investigate how a prospective buyer’s optimal home-size purchase can be determined by means of a stochastic-dominance (SD) analysis of the historical data of Hong Kong.

By means of SD analysis, the paper uses monthly property yields in Hong Kong over a 15-year period to illustrate how buyers of different risk preference may optimize their home-size purchase.

Regardless of whether the buyer eschews risk, embraces risk or is indifferent to it, in any adjacent pairing of five well-defined housing classes, the smaller class provides the optimal purchase. In addition, risk-averters focusing on total yield would prefer to invest in the smallest and second-smallest classes than in the largest class.

As the smaller class provides the optimal purchase, the smallest class affords the buyer the optimal purchase over all classes in this important housing market – at least where rental yields are of primary concern.

The findings suggest that in the Hong Kong housing market, long-term investors may be better off purchasing smaller homes. For other type of investors, it depends on their risk preference.

There is a very small body of empirical literature on housing investment, especially if the focus is on the optimal home-size purchase.

Prior to the spring 2020, education in the United States looked very similar to how it had always looked … students attended brick-and-mortar schools, used technology in their classrooms and homes to supplement their learning, and relied on the support of teachers as needed or wanted. Parents, for their part, were involved in the traditional supportive roles of checking over homework, monitoring attendance, and providing encouragement as warranted, and worked to balance this role with professional and community obligations and responsibilities. The COVID-19 pandemic swept across the globe, and parents as well as teachers were suddenly thrust into different and less familiar roles, as teaching and learning transitioned to a virtual experience. In examining this transition, a team consisting of researchers from Florida and North Carolina sought to determine the effectiveness of the parent roles in schooling from the educator perspective. In this chapter, the findings of this study are explored and analyzed, with recommendations made for research moving forward in this area.

Paula Hendricks, Director of Marketing for Rapid Reel Lawn Master Company (RRLMC), tasked with developing a plan to exploit the current trend in lawn mower purchasing patterns must craft a strategic proposal for the executive planning committee. RRLMC, a manufacturer of reel mowers, experienced an increase in sales due to a confluence of factors: high gasoline prices, increased concern with the environment, the trend toward smaller yards and a focus on health and exercise. Paula needed to develop a plan for the company to sustain the bonanza and determine whether this trend offered new opportunities for marketing.

The data for the case were collected through examination of a major reel lawn mower manufacturer in the USA, through experience teaching and using the market segmentation process, as well as personal interviews and secondary research on the history of firms within the industry. The results of a literature review have been incorporated to flesh out the discussion.

This case is targeted primarily at undergraduate students in upper-level marketing classes, e.g., Relationship Marketing, Marketing Management and Strategic Marketing. Additionally, it can be used in management classes (e.g. Strategic Management) where industry segmentation is discussed. It would also benefit introductory MBA marketing courses as this case directs students’ attention to the role of products’ perceived benefits and how markets may be segmented in order to assess and select prime segments of the market for targeting.

The differences and relations between grey sets and rough sets are discussed. Based on the concept of a rough grey set, its entropy is studied. Moreover, the grey inference resulting from a rough grey set is pointed out. The relative propositions and theorems are obtained.

Recently, classification of Arabic documents is a real problem for juridical centers. In this case, some of the Lebanese official journal documents are classified, and the center has to classify new documents based on these documents. This paper aims to study and explain the useful application of supervised learning method on Arabic texts using N‐gram as an indexing method (n  =  3).

The Lebanese official journal documents are categorized into several classes. Supposing that we know the class(es) of some documents (called learning texts), this can help to determine the candidate words of each class by segmenting the documents.

Results showed that N‐gram text classification using the cosine coefficient measure outperforms classification using Dice's measure and TF*ICF weight. Then it is the best between the three measures but it still insufficient. N‐gram method is good, but still insufficient for the classification of Arabic documents, and then it is necessary to look at the future of a new approach like distributional or symbolic approach in order to increase the effectiveness.

The results could be used to improve Arabic document classification (using software also). This work has evaluated a number of similarity measures for the classification of Arabic documents, using the Lebanese parliament documents and especially the Lebanese official journal documents Arabic corpus as the test bed.