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This paper proposes a distributed multi‐channel MAC protocol which is an extension of our early work GRID [1]. GRID is characterized by the following features: (i) it integrates a location‐aware channel assignment, (ii) it follows an “on‐demand” style to access the medium, (iii) the number of channels required is independent of the network topology, and (iv) no form of clock synchronization is required. The proposed protocol wants to further improve the GRID in two parts. First, we propose a fully distributed medium access mechanism without using a single control channel such that all of the network traffic can be distributed evenly over all data channels. Therefore, the network throughput will be increased significantly. Second, we can set the more suitable transmission range and GRID size by considering the factors of host density and packet arrival rate of the network within an specified area. Thus, all of channels will be reused more efficiently than GRID. Simulation results show that the throughput of our protocol is superior to GRID and IEEE 802.11.

We describe the first prototypes of an inter‐robot infrared localisation and communication system. The system detects the relative positions (both range and bearing) of autonomous mobile robots with an update rate of up to 20 Hz, a range of up to 3 m and an accuracy of 40 cm for range and 45° for bearing. In addition, each robot can send at least 1 byte of data to all the other robots within the range per update cycle. Flocking on a group of eight robots is used as a non‐trivial real‐world test of this system. We conclude the paper by discussing advantages, limitations, and future improvements of the system.

The basic reasons for data transmission errors are described and a distinction between baud and bit/s is drawn. Examples of error detection/correction methods are given; in their absence the recipient's ability to detect errors depends upon redundancy in the message. It is suggested that since such methods are not normally used in on‐line access to data bases, error rates typic‐ally encountered may be unacceptable when accessing nonredundant data for which accuracy is vital.

For intelligent robots in a multi‐agent system communication is essential for cooperative behavior. Here we describe the explicit communication between individual robots acting as team members of a RoboCup team playing soccer. The robots are based on the EyeBot platform. An overview of communication systems being published and a discussion of their advantages and drawbacks is followed by an introduction into multi‐agent systems and the problems we faced applying them to the task of playing soccer. Then we describe the wireless communication network in detail including the EyeBot platform, message structures, self‐configuration and error recovery. The communication allows transmission of messages between individuals, broadcasts and communication with a remote computer workstation. The communication system is a layer beneath the multi‐robot console, which is the user interface, and above the EyeBot hardware.

In response to international competition and pressure from retailers, US apparel manufacturers and their suppliers initiated the Quick Response (QR) program. QR seeks to provide retailers with the exact stock‐keeping units (SKUs) which consumers demand and to deliver these SKUs quickly. An effective QR program requires rapid transmission of data throughout the value chain, from the retailer back to apparel manufacturers, fabric producers and fibre manufacturers. Therefore, electronic data interchange (EDI) is a key component of QR and should be tightly linked with other information systems at each level of the value chain. This research is an empirical study of the degree to which EDI has been implemented by US apparel manufacturers and the extent to which EDI is integrated with other information systems. It was found that apparel manufacturers use EDI to establish tight linkages with their customers, the retailers. Manufacturers are less likely to increase their own efficiencies by linking EDI with internal information systems or by establishing EDI linkages with suppliers. The lack of supplier linkages may reduce manufacturers' ability to replenish retail inventories quickly, which is the primary objective of QR.

The technology used by an organization is significantly influenced by the organization’s preferred competitive capabilities. The Internet of things (IoT) is an important technology, which is implemented by most prominent business organizations. The purpose of this paper is to investigate the relationship between an organization’s strategies and the IoT architectures implemented by the organization.

This study has been carried out on primary data collected with the help of a structured questionnaire. The data have been analyzed by statistical techniques like cluster analysis and discriminant analysis through SPSS.

The empirical investigation of data revealed that there is a relationship between organizational strategy and IoT architectures. The three-layered architecture of the IoT is most suitable for caretakers; the three-, four- or five- layered architectures are suitable for marketeers; whereas innovators find it more suitable to use five- or more-layered architecture of the IoT. This paper draws the conclusion based on maximum likelihood rather than using statistical analyses like ANOVA. The idea behind using the maximum likelihood estimate is that there are many subjective parameters in deciding the architectures of the IoT. These subjective parameters are difficult to quantify, so it is not possible to apply ANOVA on these parameters.

This study considers three organizational strategies; the relationship between other organizational strategies and IoT architecture will be studied in future.

This study offers multiple opportunities to practitioners and consulting firms of the IoT to adopt a suitable IoT architecture according to the organizational strategy. This study equips IoT development engineers to select suitable technology for data capturing, data transmission, and data management and access for an IoT architecture.

Although a lot of work has already been done on the architecture of IoT for different industries and businesses, to the best of our knowledge, this is the first study that relates organizational strategies to IoT architectures. This study applies to all the major industry types.

The paper aims to introduce an efficient routing algorithm for wireless sensor networks (WSNs). It proposes an improved evaporation rate water cycle (improved ER-WC) algorithm and outlining the systems performance in improving the energy efficiency of WSNs. The proposed technique mainly analyzes the clustering problem of WSNs when huge tasks are performed.

This proposed improved ER-WC algorithm is used for analyzing various factors such as network cluster-head (CH) energy, CH location and CH density in improved ER-WCA. The proposed study will solve the energy efficiency and improve network throughput in WSNs.

This proposed work provides optimal clustering method for Fuzzy C-means (FCM) where efficiency is improved in WSNs. Empirical evaluations are conducted to find network lifespan, network throughput, total network residual energy and network stabilization.

The proposed improved ER-WC algorithm has some implications when different energy levels of node are used in WSNs.

This research work analyzes the nodes’ energy and throughput by selecting correct CHs in intra-cluster communication. It can possibly analyze the factors such as CH location, network CH energy and CH density.

This proposed research work proves to be performing better for improving the network throughput and increases energy efficiency for WSNs.

Utilization of electromagnetic wave (EMW) sensors in an underwater environment has the potential to increase the data rate compared to acoustic-based sensors because of the ability to use larger signal bandwidth. Nevertheless, EMW signals has the drawback of large signal attenuation in underwater, attributed to the high relative permittivity and conductivity of water compared to the atmosphere, hence employment of wide signal bandwidth is necessary to balance the data rate-attenuation trade-off. The purpose of this paper is to analyze the characteristics of both narrowband and wideband EMW signal propagation underwater and devise a path loss model for both cases.

Path loss measurement was conducted using a point-to-point configuration in a laboratory water tank while transmitting narrowband and wideband signals between a pair of wideband underwater antennas. The wideband underwater antennas use buffer-layer structures as the impedance matching layer to optimize the antenna performance when operating underwater. The path loss for narrowband signal was modeled using a multi-layer propagation equation in lossy medium considering losses at the medium boundaries. For the case of the wideband signal, a modified version of the model introducing power integration over bandwidth is adopted. These models were formulated through numerical simulations and verified by measurements.

The measured narrowband path loss marked an 80 dB attenuation using 800 MHz at 2 m distance. The proposed narrowband model agrees well with the measurements, with approximately 3 dB modeling error. Utilization of the proposed wideband path loss model resulted in a reduction of the gradient of the path loss curve compared to the case of the narrowband signal. The measured wideband path loss at 2 m distance underwater was approximately −65 dB, which has been shown to enable a working signal-to-noise ratio of 15 dB. This proves the potential of realizing high data rate transmission using the wideband signal.

The paper proposed a wideband propagation model for an underwater EMW sensor network, using power integration over bandwidth. The effectiveness of using wideband EMW signals in reducing path loss is highlighted, which is seldom discussed in the literature. This result will be of useful reference for using wideband signals in designing a high data rate transmission system in underwater wireless sensor networks, for example, in link budget, performance estimation and parameter design of suitable transmission scheme.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

Internet has changed radically in the way people interact in the virtual world, in their careers or social relationships. IoT technology has added a new vision to this process by enabling connections between smart objects and humans, and also between smart objects themselves, which leads to anything, anytime, anywhere, and any media communications. IoT allows objects to physically see, hear, think, and perform tasks by making them talk to each other, share information and coordinate decisions. To enable the vision of IoT, it utilizes technologies such as ubiquitous computing, context awareness, RFID, WSN, embedded devices, CPS, communication technologies, and internet protocols. IoT is considered to be the future internet, which is significantly different from the Internet we use today. The purpose of this paper is to provide up-to-date literature on trends of IoT research which is driven by the need for convergence of several interdisciplinary technologies and new applications.

A comprehensive IoT literature review has been performed in this paper as a survey. The survey starts by providing an overview of IoT concepts, visions and evolutions. IoT architectures are also explored. Then, the most important components of IoT are discussed including a thorough discussion of IoT operating systems such as Tiny OS, Contiki OS, FreeRTOS, and RIOT. A review of IoT applications is also presented in this paper and finally, IoT challenges that can be recently encountered by researchers are introduced.

Studies of IoT literature and projects show the disproportionate importance of technology in IoT projects, which are often driven by technological interventions rather than innovation in the business model. There are a number of serious concerns about the dangers of IoT growth, particularly in the areas of privacy and security; hence, industry and government began addressing these concerns. At the end, what makes IoT exciting is that we do not yet know the exact use cases which would have the ability to significantly influence our lives.

This survey provides a comprehensive literature review on IoT techniques, operating systems and trends.