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This paper aims to present a domain decomposition method to overcome the challenges posed by multi-domain, multi-scale high frequency problems.

A hybrid finite element and boundary integral procedure is also presented that allows for domains to employ different solution methods in different subdomains.

By decomposing large electromagnetic regions into smaller domains, the finite element method can cope with the simulation of electrically large problems.

Real life examples demonstrate the accuracy and efficiency of the new method.

The Robin transmission condition (RTC) is applied to link the domains and preserve field continuity on interfaces.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

Starting from the premise that digital screens are pervading our everyday urban and social environments to serve a variety of purposes, the purpose of this paper is to show how screens can be made aware of what is happening around them and – based on specific strategies – adapt accordingly the advertisement flow to supply to users more engaging contents.

The paper presents an overview of future pervasive advertisement scenarios, and sketches the architecture and implementation of a system for adaptive context‐aware pervasive advertisement. Subsequently, with the help of a simulation environment, the paper evaluates the performances of several adaptive context‐aware advertisement strategies, and compares them against non‐adaptive ones.

The paper demonstrates that, in a wide range of conditions, an advertisement system based on adaptive context‐aware strategies leads to a gain in terms of commercial value with respect to traditional non‐adaptive strategies for advertisement broadcasting.

A system for pervasive advertisement could be easily brought to life, leading advertisement companies to a much more targeted exploitation of the screen resource and, eventually, to higher revenues.

Adaptive advertisement systems can offer notable commercial advantages over traditional advertisement systems even when visitors demonstrate poor collaboration towards the system.

The purpose of this paper is to present topological derivatives-based reconstruction algorithms to solve an inverse scattering problem for penetrable obstacles.

The method consists in rewriting the inverse reconstruction problem as a topology optimization problem and then to use the concept of topological derivatives to seek a higher-order asymptotic expansion for the topologically perturbed cost functional. Such expansion is truncated and then minimized with respect to the parameters under consideration, which leads to noniterative second-order reconstruction algorithms.

In this paper, the authors develop two different classes of noniterative second-order reconstruction algorithms that are able to accurately recover the unknown penetrable obstacles from partial measurements of a field generated by incident waves.

The current paper is a pioneer work in developing a reconstruction method entirely based on topological derivatives for solving an inverse scattering problem with penetrable obstacles. Both algorithms proposed here are able to return the number, location and size of multiple hidden and unknown obstacles in just one step. In summary, the main features of these algorithms lie in the fact that they are noniterative and thus, very robust with respect to noisy data as well as independent of initial guesses.

Bluetooth wireless technology is a low power, low cost and short‐range RF technology that permits communication between bluetooth enabled devices, and focuses on replacement of cables between electronic devices. Communication between Bluetooth devices follows a strict master‐slave scheme. Each master device can have up to 7 active slaves and forms a so called piconet. In Bluetooth employing conventional scheduling policies such as Round Robin (RR), POLL or NULL packet is sent when the Master or Slave node does not have any data to send which causes a significant waste of resources. The DRR (Deficit Round Robin) scheduling algorithm can avoid the waste of time and slot of the RR scheduling at the sacrifice of fairness. In this paper we propose an improved DRR (IDRR) scheduling algorithm which effectively combines the DRR and bin packing algorithm. Computer simulation reveals that slot utilization is increased up to about 60% while the total number of used slots is decreased up to about 100%. The proposed IDRR scheduling is thus effective for not only basic data transmission but also real‐time multimedia data transmission.

The purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and efficient transmission scheme over various types' services. The proposed algorithm is evaluated by simulation results.

A big problem for wireless communication is the limited time/frequency resources. Therefore, the most important issue is how to utilize these limited resources to transmit various services over a wireless broadband network, especially for MBMS services. In this paper, resource allocation mechanism in a full unicast system is first analyzed with three classical methods, then improved modulation and coding schemes (MCS) methods are proposed in a full multicast system to improve system throughput and spectral efficiency. Based on the foregoing discussions, research on resource allocation mechanism for mixed multicast and unicast traffic is developed in single‐cell and multi‐cell system (MBSFN, MBMS over single frequency network), respectively. Different transmission proportions between multicast and unicast are analyzed and a multiplexing scenario is also considered.

Resource allocation is a hot topic in wireless communication and there are many investigations on it. However, resource allocation for multicast system, especially for mixed multicast and unicast traffic system, is still a problem worthy of further study. Under same transmission condition in a single cell scenario, system throughput in multicast mode is worse than in unicast mode, which is partly because the number of valid date in multicast resource block (RB) is less than the one in unicast in 3GPP LTE/LTE‐A, on the other hand, because that multicast need to select a relative low MCS to satisfy most MBMS users, even the users with a very poor transmission condition. Fortunately, multicast in MBSFN (MBMS over single frequency network) transfer mode can largely improve system performance.

Improved MCS selection schemes are proposed for full multicast transmission and three transmission scenarios for mixed multicast and unicast traffic are presented to discuss resource allocation mechanism over various types' services. Simulation results show that system performance of multicast system can be greatly enhanced in MBSFN transmission mode, especially with MIMO technology.

The purpose of this study is to introduce the reproducing kernel algorithm for treating classes of time-fractional partial differential equations subject to Robin boundary conditions with parameters derivative arising in fluid flows, fluid dynamics, groundwater hydrology, conservation of energy, heat conduction and electric circuit.

The method provides appropriate representation of the solutions in convergent series formula with accurately computable components. This representation is given in the W(Ω) and H(Ω) inner product spaces, while the computation of the required grid points relies on the R_(y,s) (x, t) and r_(y,s) (x, t) reproducing kernel functions.

Numerical simulation with different order derivatives degree is done including linear and nonlinear terms that are acquired by interrupting the n-term of the exact solutions. Computational results showed that the proposed algorithm is competitive in terms of the quality of the solutions found and is very valid for solving such time-fractional models.

Future work includes the application of the reproducing kernel algorithm to highly nonlinear time-fractional partial differential equations such as those arising in single and multiphase flows. The results will be published in forthcoming papers.

The study included a description of fundamental reproducing kernel algorithm and the concepts of convergence, and error behavior for the reproducing kernel algorithm solvers. Results obtained by the proposed algorithm are found to outperform in terms of accuracy, generality and applicability.

Developing analytical and numerical methods for the solutions of time-fractional partial differential equations is a very important task owing to their practical interest.

This study, for the first time, presents reproducing kernel algorithm for obtaining the numerical solutions of some certain classes of Robin time-fractional partial differential equations. An efficient construction is provided to obtain the numerical solutions for the equations, along with an existence proof of the exact solutions based upon the reproducing kernel theory.

Professional touching behavior (PTB), defined as intentional touching behavior that occurs between organizational members and that falls within the boundaries of appropriateness and professionalism in the workplace, is prevalent in organizations. Scholars from multiple disciplines, including human resources researchers, have acknowledged the importance of physical contact for facilitating interpersonal communication and relationship-building. However, PTB may not only elicit positive reactions from those who receive it but also negative reactions as well, with implications for social dynamics in organizations. PTB can, on the one hand, fulfill employees’ desires for interpersonal connection; at the same time, such physical contact at work can represent a threat to employees’ health. To explain the nature and implications of these divergent effects of receiving PTB, the authors draw upon sociometer theory and behavioral immune system (BIS) theory to model the emotional, cognitive, and physiological processes via which, and the conditions under which, receiving such behavior will result in socially functional responses and prompt subsequent prosocial behavior, and when PTB will be perceived as a health risk and prompt withdrawal behavior. The theoretical framework of this chapter expands our conceptual understanding of the consequences of interpersonal physical contact at work and has important human resources management (HRM) implications for organizational managers.

Recent experiments show that feedback transmission can mitigate opportunistic behavior in repeated social dilemmas. Two nonexcludable explanations have been investigated: strategic signaling and nonmonetary sanctioning. This literature builds on the intuition that under both partner matching (where the same groups of players interact many times) and stranger matching (where groups change continuously), feedback may work as a nonmonetary sanctioning device, but only the former also allows for strategic signaling. Empirical evidence on the two explanations is mixed. Moreover, the usual design may give rise to confounding matching protocol effects.

My experiment provides a novel empirical testbed for different channels by which feedback – costless disapproval points – may affect behavior in a repeated public goods game. In particular, it is based on a random matching scheme that neutralizes the confounding effects of different matching protocols on behavior.

The transmission of feedback is found to foster prosocial behavior. The data favor the nonmonetary sanctioning explanation rather than the signaling hypothesis.

This study provides a novel set of evidence that (i) communication may mitigate selfishness in social dilemmas and (ii) the source of this phenomenon may be linked to the emotional reaction that communication evokes in humans.

Wallis has a chain of some 70 fashion shops in the UK and Europe, through which they sell clothes they manufacture themselves. Robin Happe joined Wallis some three years ago, and this paper outlines the methods which the company uses to furnish the data necessary for the reporting system around which merchandising procedures revolve. He describes how these methods have evolved over the years to keep pace with the general growth in the company's activities, using, currently, sophisticated data entry techniques. This paper was originally presented at the Information Studies conference ‘Data communications for retail management’, in London in March. Robin Happe is no longer with Wallis, having taken up a post in the West Indies.