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This paper presents an overview on the Auto‐ID (Automatic Identification) technologies testbed that has been established at the University of Missouri‐Rolla (UMR) with the objective of supporting research, development, and implementation of Auto‐ID technologies in network‐centric manufacturing environments.

UMR's Auto‐ID testbed uses a unique hardware‐in‐the‐loop simulation methodology, which integrates decision‐making model development with the design of networking topology and data routing/scheduling schemes, in order to develop, test, and implement viable Auto‐ID solutions. The methodology is founded on a 3‐level integrated model: controller simulation, distributed controller simulation, and distributed controller simulation with hardware‐in‐the‐loop.

This paper discusses two case studies that highlight the effective use of RFID technology, its potential advantages, challenges, and deficiencies stemming from particular applications. These applications include dock doors, automated guided vehicles, conveyor and automated storage/retrieval systems, integration of RFID middleware with programmable logic controllers, and inventory management of time‐sensitive materials.

The paper presents an innovative idea: hardware‐in‐the‐loop simulation methodology to design automation systems. The approach has been implemented on a variety of applications, which are presented in the paper as case studies.

The purpose of this paper is to discuss two‐dimensional electromagnetic diffraction by a finite set of parallel nonlinear rods (optical Kerr effect). To point out the versatility of this approach, a nonlinear (Kerr‐effect) finite crystal is considered.

In this paper, a new route for obtaining the scattered field by nonlinear obstacles is proposed. The basic idea consists in simulating the real incident field (e.g. plane waves) by a virtual field emitted by an appropriate antenna, located in a meshed domain, and encompassing or lying above the obstacles. This latest problem is then solved by a finite element method that is well suited to take into account the material inhomogeneities due to the nonlinearity of the permittivity.

The transmission through a finite Kerr crystal doped by a microcavity is given and a resonant wavelength is obtained. At this resonant wavelength, it is shown that the nonlinearity has a large influence on the behaviour of the electromagnetic wave.

Introducing the concept of virtual antenna, the paper proposes a rigorous treatment of the scattering of an electromagnetic wave by a bounded nonlinear obstacle of arbitrary shape.

This paper aims to present an approach of utilizing multiple-input multiple-output (MIMO) radar concept to enhance pedestrian classification in automotive sensors. In a practical environment, radar signals reflected from pedestrians and slow-moving vehicles are similar in terms of reflecting angle and Doppler returns, inducing difficulty for target discrimination. An efficient discrimination between the two targets depends on the ability of the sensor to extract unique characteristics from each target, for example, by exploiting Doppler signatures. This study describes the utilization of MIMO radar for Doppler measurement and demonstrates its application to improve pedestrian classification through actual laboratory measurements.

Multiple non-modulated sinusoidal signals are transmitted orthogonally over a MIMO array using time division scheme, illuminating human and non-human targets. The reflected signal entering each of the receiving antenna are combined at the radar receiver prior to Doppler processing. Doppler histogram was formulated based on a series of measurements, and the Doppler spread of the targets was determined from the histograms. Results were compared between MIMO and conventional single antenna systems.

Measurement results indicated that the MIMO configuration provides able to capture more Doppler information compared to conventional single antenna systems, enabling a more precise discrimination between pedestrian and other slow-moving objects on the road.

The study demonstrated the effectiveness of using MIMO configuration in radar-based automotive sensor to enhance the accuracy of Doppler estimation, which is seldom highlighted in literature of MIMO radars. The result also indicated its usefulness in improving target discrimination capability of the radar, through actual measurement.

In this paper, a wireless network consisting of multiple source-destination pairs, which communicate peer-to-peer with the help of multiple Amplify-and-Forward relays is considered. The purpose of this paper is to minimize the total relay transmit power subject to a sum rate threshold.

It is shown that finding a beamforming matrix which satisfies the investigation’s goal is a non-convex optimization problem. Therefore, a semidefinite relaxation technique is used to turn it into a semidefinite programming problem. Thus, it can be effectively solved by interior point methods.

Simulation results show that the total relay transmit power decreases with the number of relays. In addition, it is shown that relays’ power consumption decreases when the quality of uplink and/or downlink channels improves. In order to compare the proposed optimization algorithm to two conventional approaches, energy efficiency criterion used for performance comparison and complexity order for evaluating computational complexity. Although the proposed algorithm does not change the order of complexity, it needs a few more iterations to find the best result which leads to a double the processing time compared to existing approaches.

In the present optimization problem, coefficient ß is used instead of a constant factor 2 in the original optimization problem. It is shown that by changing parameter ß between 1 and 2, a lower power consumption for a target sum rate can be achieved.

The purpose of this paper is to introduce an orthogonal frequency‐division multiplexing (OFDM)‐based 2‐phase physical‐layer feedback space (PFS) for distributed relay selection (RS) in virtual multiple‐input multiple‐output (VMIMO) systems. The proposed method is evaluated with numeric and simulation results.

Unlike minislots used in current MAC layer feedback, the authors introduce physical‐layer feedback space (PFS) which hosts one‐bit for each candidate relay (CR), for instance, a 48‐subcarrier OFDM symbol hosts 48 bits. In the two‐phase feedback procedure, each CR firstly hears the invitation and respond between cluster heads (CH) of upper‐/down‐stream cluster and decides whether to be a qualified relay or not. Then if it is qualified, it randomly selects one subcarrier and sends a pre‐equalized one‐bit feedback. The upper‐stream CH evaluate all feedbacks in PFS, then selects all or a subset of relays with successful feedback and broadcasts its decision to all nodes. Although the number of successful feedbacks (NSF) drops as number of CR increases (NCR), 7∼8 CR can be selected with high probability when NCR is triple that of total subcarriers (48).

In current literature, several traditional MAC layer feedback mechanisms are designed for relay selection in virtual MIMO (VMIMO) system most of which are based upon feedback minislots. For such methods, the number of active nodes should be estimated first and known to all participating nodes to choose optimal feedback possibility to obtain best successful feedback possibility. Furthermore, each minislot should include unique identification of candidate relay thus such methods can NOT be referred as one‐bit feedback. In the new method, though OFDM subcarriers play the same role as minislots, they are exactly one‐bit fashioned and occupies only multiple OFDM symbols which is much shorter than that in current methods.

By using physical‐layer feedback space, exactly only one‐bit is required for each candidate relay to send its feedback, and the overall overhead introduced for all of them is K‐bit provided by the required PFS, which spans only fixed duration of the PFS, which is one or more OFDM symbols. Therefore, the proposed scheme can greatly reduce overhead and feedback delay during relay selection.

Non-orthogonal multiple access (NOMA) is a much hopeful scheme, which is deployed to enhance the spectral efficiency (SE) significantly, and it also enhances the massive access that has attained substantial concern from industrial and academic domains. However, the deployment of superposition coding (SC) at the receiver side resulted in interference. For reducing this interference, “multi-antenna NOMA” seems to be an emerging solution. Particularly, by using the channel state information at the transmitter, spatial beam forming could be deployed that eliminates the interference in an effective manner.

This survey analyzes the literature review and diverse techniques regarding the NOMA-based spatial modulation (SM) environment. It reviews a bunch of research papers and states a significant analysis. Initially, the analysis depicts various transmit antenna selection techniques that are contributed in different papers. This survey offers a comprehensive study regarding the chronological review and performance achievements in each contribution. The analytical review also concerns on the amplitude phase modulation (APM) selection schemes adopted in several contributions. Moreover, the objective functions adopted in the reviewed works are also analyzed. Finally, the survey extends with various research issues and its gaps that can be useful for the researchers to promote improved future works on NOMA-based SM.

This paper contributes to a review related to NOMA-based SM systems. Various techniques and performance measures adopted in each paper are analyzed and described in this survey. More particularly, the selection of transmission antenna and APM are also examined in this review work. Moreover, the defined objective function of each paper is also observed and made a chronological review as well. Finally, the research challenges along with the gaps on NOMA-based SM systems are also elaborated.

This paper presents a brief analysis of NOMA-based SM systems. To the best of the authors’ knowledge, this is the first work that uses NOMA-based SM systems to enhance SE.

This paper aims to discuss over imperfect reporting channel the performance of cooperative spectrum sensing (CSS). It is investigated that imperfect reporting channel introduces some lower bound in false alarm probability (Pf). The lower bound of probability of false alarm linearly increases with the probability of reporting error.

To solve this problem, a transmit diversity-based CSS method is proposed, and to improve the detection performance, square law selection (SLS) diversity is used.

It is observed that detection probability increases up to 11.55 per cent when SLS diversity is applied, and lower bound Qf decreases up to 80 per cent when transmit diversity is applied.

No literature is available to the best of the authors’ knowledge that measures the performance of CSS with respect to parameters as reported in this paper.

This chapter examines Pelagic Sargassum seaweed that has been washing up on shores from Mexico to Ghana in record amounts over the last decade. Increase in Sargassum has had a devastating impact on fisheries and tourism including the livelihoods of coastal communities and nearshore ecosystems. This increase has also caused significant health problems due to the exposure of rotting sargassum. Current science informing this increase points to climatic change and ocean eutrophication. Even as the scientific phenomena is studied, there have been numerous management strategies deployed to adapt to heavy seasonal washups, to build resilience in affected sectors and communities and even explore sustainable uses of the seaweed material turned to viable market products. Here, we focus on public management and administration of Sargassum to consider how the micro- and macroimpacts affect our societies including government and private sector responses to seaweed removal and legal, regulatory, and administrative approaches to such “pollution” that highlight process, jurisdictional, and political imperatives. We unpack via the Institutional Analysis and Development (IAD) lens to raise and uncover several interesting points regarding how we build resilience to environmental change, manage national systems in the face of unclear nature-based phenomena, and approach to equitable sustainable development.

The purpose of this paper is to build a new deployable antenna with folded scissors ribs and to evaluate the reasonable characteristics of this new structure.

Based on the TerrStar-1 satellite, virtual design and shapes forming are considered in this paper with the structure design of the new antenna. Considering the relaxation units in net surface, form-finding evaluation is used to build mathematical model and operate the optimization algorithm so that the design of the new antenna with folded scissors ribs is achieved. Simulations are carried out to verify the antenna proposed.

It is found that the antenna with folded scissors ribs can be developed smoothly in the space.

The proposed the antenna with folded scissors ribs can be considered as a fall-back alternative for large antenna, with a diameter of over 10 m in the space, or is seen as another option for the system with a simple rigid structure.

Different from traditional antenna, it provides a valuable reference for the further research of large deployable antenna in space. The antenna in this paper is able to develop more than 30 m of diameter. Meanwhile, the surface density and the natural frequency and the root-mean-square error in surface are superior to those of the traditional antenna.

This paper aims to synthesize a modular deployable truss antenna with the lower degree of freedom (DOF) and larger folding ratio. Because of the advantages of this kind of new truss antenna, the modules that make up the antenna can be deployed together by the synchronous motor drivers instead of twist springs to realize the controllable deployment.

The closed-loop branch equivalence method is proposed to synthesize the single DOF module and the large deployable reflector. The complex mechanism can be equivalently replaced by a simpler mechanism based on screw theory. The motion pairs are synthesized and optimized to make the curved surface achieve to the maximum folding ratio when the modular parabolic truss antenna is folded.

The results show that the 3(3RR-3RRR)-3RRR-3RRR planar module is a single DOF mechanism. Additionally, the adjacent parts of every two modules are connected with universal joints to obtain the new truss antenna when the modules are networked.

The configuration of this new modular deployable truss antenna can be synthesized to design the structure, and the proposed method can be applied to other space multi-loop coupling mechanism and other spacecraft.

This paper presents an approach to synthesizing the motion pairs, as well as the DOF analysis. The results lay a foundation for the further analysis of the deployable control and dynamics of this kind of antenna. And the new modular truss antenna has a practical application in aerospace engineering.