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This chapter presented cognitive radio networks in construction. The construction industry requires an efficient bandwidth of wireless technology for effectiveness without delay. The persistence of challenges with the investment in third generation is a great concern, and this chapter identified investing in fifth generation (as an alternative) to enlarge bandwidth for better effectiveness that is capable of dealing with unavailable or scarcity of radio spectrum. The application of fifth generation will permit efficient utilisation of the radio spectrum by the primary and secondary users to detect the spectrum parameters which will highlight the direct and adequate interaction with the radio channel. This chapter further considered the usage of this technology as it relates to permitting sharing of sense in the spectrum.

This chapter presented radio frequency identification (RFID) as a technological gadget used in various industries to improve information and tracking equipment. The adoption of RFID in the construction industry has been scarcely used due to the dissemination of its potential to construction professionals in the industry. RFID is generally used as a wireless device that transmits information using radio waves. The benefits associated with using RFID in the construction industry were discussed along with challenges, and its functions to the construction process.

Farmers in rural areas are generally not well empowered with knowledge and innovations to solve their agricultural problems in spite of the growing presence of such knowledge resulting from research and innovation activities across the globe. This study aims to document approaches, impact and impediments of using village knowledge centers (VKCs) to transfer agricultural knowledge and innovations.

To achieve the objective of the study, a case study research design was used to investigate the impact of a selected VKC as institutional innovation in agricultural technology outreach and extension in rural Tanzania. Primary data was collected through semi-structured interviews, focus group discussions and observation methods. Besides, secondary sources such as reports were used to complement primary data during fieldwork.

The study reveals that various approaches are used by the VKC to transfer knowledge and innovation to farmers. The use of the multi-actor platform (MAP) to run the VKC ensures inclusive knowledge production and sharing among different actors. The findings also suggest that knowledge and innovation co-creation is constructed with various knowledge systems actors to enhance the use of research generated. Accordingly, the findings show that the university efforts are an important catalyst for integrated knowledge, technology and innovation systems in rural settings.

The present study reveals different limitations associated with the use of a single case study design. The single-case design provided researchers with little basis for generalisation of the study findings and conclusions. Aside from that, the use of a cross-sectional design did not help the researchers to validate the findings and conclusions. To address these limitations, the study recommends similar studies that will adopt different types of longitudinal design such as cohort and diary methods. Apart from this, a future study to investigate the tangible impact of VKC on knowledge and innovation transfer is recommended.

Considering the novelty of the MAP approach in Tanzania and the dearth of studies reporting on how the village knowledge center works and how effective it is, the present study provides insights on the approaches, impact and impediments.

Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure monitoring. One of the main challenges for underground WSN deployment is the limited range (less than 3 m) at which reliable wireless underground communication can be achieved using radio signal propagation through the soil. To overcome this challenge, the purpose of this paper is to investigate a new approach for wireless underground communication using acoustic signal propagation along a buried water pipe.

An acoustic communication system was developed based on the requirements of low cost (tens of pounds at most), low power supply capacity (in the order of 1 W-h) and miniature (centimetre scale) size for a wireless communication node. The developed system was further tested along a buried steel pipe in poorly graded SAND and a buried medium density polyethylene (MDPE) pipe in well graded SAND.

With predicted acoustic attenuation of 1.3 dB/m and 2.1 dB/m along the buried steel and MDPE pipes, respectively, reliable acoustic communication is possible up to 17 m for the buried steel pipe and 11 m for the buried MDPE pipe.

Although an important first step, more research is needed to validate the acoustic communication system along a wider water distribution pipe network.

This paper shows the possibility of achieving reliable wireless underground communication along a buried water pipe (especially non-metallic material ones) using low-frequency acoustic propagation along the pipe wall.

The purpose of this paper is to present an up-to-date survey on the non-orthogonal multiple access (NOMA) technique with co-operative strategy, a fast-evolving fifth-generation (5 G) technology. NOMA is used for serving many mobile users, both in power and code domains. This paper considers the power-domain NOMA, which is now discussed as NOMA.

The first part of the paper discusses NOMA-based cooperative relay systems using different relay strategies over different channel models. In various research works, the analytical expressions of many performance metrics were derived, measured and simulated for better performance of the NOMA systems. In the second part, a brief introduction to diversity techniques is discussed. The multiple input and multiple output system merged with cooperative NOMA technology, and its future challenges were also presented in this part. In the third part, the paper surveys some new conceptions such as cognitive radio, index modulation multiple access, space-shift keying and reconfigurable intelligent surface that can be combined with NOMA systems for better performance.

The paper presents a brief survey of diverse research projects being carried out in the field of NOMA. The paper also surveyed two different relaying strategies that were implemented in cooperative NOMA over different channels and compared several performance parameters that were evaluated and derived in these implementations.

The paper provides a scope for recognizable future work and presents a brief idea of the new techniques that can be united with NOMA for better performance in wireless systems.

In the mid-2000s, the operator of New York City’s mass transit network committed more than a half-billion dollars to military contractor Lockheed Martin for a security technology capable, in part, of inferring threats based on analysis of data streams, of developing response strategies, and taking automated action toward alerts and calamities in light of evolving circumstances. The project was a failure. This chapter explores the conceptualization and development of this technology – rooted in cybernetics – and compares its conceptual underpinnings with some situated problems of awareness, communication, coordination, and action in emergencies as they unfold in one of the busiest transport systems in the world, the New York subway. The author shows how the technology, with all the theatrical trappings of a “legitimate” security solution, was apparently conceived without a grounded understanding of actual use-cases, and the degree to which the complex interactions which give rise to subway emergency can be anticipated in – and therefore managed through – a technological system. As a case-study, the chapter illustrates the pitfalls of deploying technology against problems which are not well-defined in the first place, to the neglect of investments against much more fundamental problems – such as inadequate communication systems, and unstable relationships with emergency response agencies – which might offer guaranteed benefits, and indeed lay a firm groundwork for future deployment of more ambitious technology.

Automatic modulation recognition (AMR) is a challenging problem in intelligent communication systems and has wide application prospects. At present, although many AMR methods based on deep learning have been proposed, the methods proposed by these works cannot be directly applied to the actual wireless communication scenario, because there are usually two kinds of dilemmas when recognizing the real modulated signal, namely, long sequence and noise. This paper aims to effectively process in-phase quadrature (IQ) sequences of very long signals interfered by noise.

This paper proposes a general model for a modulation classifier based on a two-layer nested structure of long short-term memory (LSTM) networks, called a two-layer nested structure (TLN)-LSTM, which exploits the time sensitivity of LSTM and the ability of the nested network structure to extract more features, and can achieve effective processing of ultra-long signal IQ sequences collected from real wireless communication scenarios that are interfered by noise.

Experimental results show that our proposed model has higher recognition accuracy for five types of modulation signals, including amplitude modulation, frequency modulation, gaussian minimum shift keying, quadrature phase shift keying and differential quadrature phase shift keying, collected from real wireless communication scenarios. The overall classification accuracy of the proposed model for these signals can reach 73.11%, compared with 40.84% for the baseline model. Moreover, this model can also achieve high classification performance for analog signals with the same modulation method in the public data set HKDD_AMC36.

At present, although many AMR methods based on deep learning have been proposed, these works are based on the model’s classification results of various modulated signals in the AMR public data set to evaluate the signal recognition performance of the proposed method rather than collecting real modulated signals for identification in actual wireless communication scenarios. The methods proposed in these works cannot be directly applied to actual wireless communication scenarios. Therefore, this paper proposes a new AMR method, dedicated to the effective processing of the collected ultra-long signal IQ sequences that are interfered by noise.

The appropriation of artificial intelligence (AI) into everyday workplace practices is becoming pervasive. Some of the industries that have seen the improved appropriation of AI include the automotive industry, food chains and other retail businesses. The media industry in developed countries has also been appropriating AI into newsrooms ecologies. This development has left news media workers, especially in developing countries, questioning the viability of their jobs in the foreseeable future as machines take over and disrupt newsmaking and production processes. The unknowns that come with AI adoption have been met with both utopian and dystopian views in African newsrooms, especially in countries that understand less on how to deploy AI affordances. Premised on the technology acceptance model and the concept of technological appropriation and a qualitative methodology that used structured interviews with community media journalists from the Western Cape province of South Africa, this chapter examined journalists' perceptions of AI deployment in the community media space. The findings of the study show that community media journalists hold both utopian and dystopian views on the utility of AI in the community media space. While most journalists perceive AI as enhancing the efficiency and accuracy of the newsmaking process, there is a significant number of journalists who perceive AI as inimical to the legitimacy and credibility of the profession. Furthermore, AI is also seen as a threat to jobs within the journalism profession. These findings resonate with previous studies that have shown that journalists are divided on the perceived utility of AI in newsrooms.

The technical report released by the National Transportation Safety Board, along with the primary flight cockpit voice recorder data and archival interview data, were used as the basis for this case. Other available public data such as news reports were used to round out the synopsis of the case study.

United Express Flight 5925 was a scheduled commuter passenger flight operated by Great Lakes Airlines with a Beechcraft 1900 twin turboprop. It was a regularly scheduled flight from Chicago O'Hare International Airport to Quincy, Illinois, with an intermediate stop in Burlington, Iowa. Drawing from various first-hand accounts (cockpit voice recorder) and secondary evidence (news reports, archival interview data, and online sources) of the tragedy, the case provides a detailed account of the key events that took place leading up to the accident at Quincy regional airport. The case describes how the radio interactions, a jammed door and degradation of situational awareness all contributed to the accident. Through many of the quotes in the text and eyewitness accounts, readers gain an understanding of the impressions and perceptions of the pilots, including how they felt about many of the critical decisions in the last minutes of the flight and the situation at the airport.

When the authors teach this case, the students are required to read it as pre-reading before class. Various readings and materials (see supplemental readings below and Exhibit 3) are made available to students before class, and the instructor can choose to use some of these materials to further explore areas of interest. This case is best explored over a 90-min session but could be expanded to take up one 3-h session. This case can be covered in an undergraduate senior capstone organizational behaviour seminar, any general organizational behaviour class (including introductory in nature), an undergraduate communication theory class or an MBA class that focuses on applied organizational behaviour concepts. It works particularly well in the MBA class, as students with work experience can make the links between the behaviours explored in the case and their everyday workplaces.

Filter design plays an essential role in most communication standards. The essential element of the software-defined radio is a channelizer that comprises several channel filters. Designing filters with lower complexity, minimized area and enhanced speed is a demanding task in currently prevailing communication standards. This study aims to propose an efficient reconfigurable residue number system (RNS)-based multiply-accumulate (MAC) channel filter for software radio receivers.

RNS-based pipelined MAC module for the realization of channel finite impulse response (FIR) filter architecture is considered in this work. Further, the use of a single adder and single multiplier for realizing the filter architecture regardless of the number of taps offers effective resource sharing. This design provides significant improvement in speed of operation as well as a reduction in area complexity.

In this paper, two major tasks have been considered: first, the RNS number conversion is performed in which the integer is converted into several residues. These residues are processed in parallel and are applied to the MAC-FIR filter architecture. Second, the MAC filter architecture involves pipelining, which enhances the speed of operation to a significant extent. Also, the time-sharing-based design incorporates a single partial product-based shift and add multiplier and single adder, which provide a low complex design. The results show that the proposed 16-tap RNS-based pipelined MAC sub-filter achieves significant improvement in speed as well as 89.87% area optimization when examined with the conventional RNS-based FIR filter structure.

The proposed MAC-FIR filter architecture provides good performance in terms of complexity and speed of operation because of the use of the RNS scheme with pipelining and partial product-based shift and adds multiplier and single adder when examining with the conventional designs. The reported architecture can be used in software radios.