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Multiple-input multiple-output (MIMO) combined with multi-user massive MIMO has been a well-known approach for high spectral efficiency in wideband systems, and it was targeted to detect the MIMO signals. The increasing data rates with multiple antennas and multiple users that share the communication channel simultaneously lead to higher capacity requirements and increased complexity. Thus, different detection algorithms were developed for the Massive MIMO.

This paper focuses on the various literature analyzes on various detection algorithms and techniques for MIMO detectors. Here, it reviews several research papers and exhibits the significance of each detection method.

This paper provides the details of the performance analysis of the MIMO detectors and reveals the best value in the case of each performance measure. Finally, it widens the research issues that can be useful for future researchers to be accomplished in MIMO massive detectors

This paper has presented a detailed review of the detection of massive MIMO on different algorithms and techniques. The survey mainly focuses on different types of channels used in MIMO detections, the number of antennas used in transmitting signals from the source to destination, and vice-versa. The performance measures and the best performance of each of the detectors are described.

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.

This paper aims to establish a multi-input equilibrium manifold expansion (EME) model for gas turbine (GT). It proposes that the extension of model input dimension is realized based on similarity theory and affine structure in the framework of single-input EME model. The study aims to expand the scope of application of the EME model so that it can be used for the control or fault diagnosis of GTs.

In this paper, the concepts of corrected equilibrium manifold expansion (CEME) model and multi-cell equilibrium manifold expansion (MEME) model are first proposed. This paper uses theoretical analysis and simulation experiments to demonstrate the effectiveness of the bilayer equilibrium manifold expansion (BEME) model, which is a combination of the CEME and the MEME models. Simulation experiments include confirmatory experiments and comparative experiments.

The paper provides a new sight into building a multiple-input EME (MI-EME) model for GTs. The proposed method can build an accurate and robust MI-EME model that has superior performance compared with widely used nonlinear models including Wiener model (WM), Hammerstein model (HM), Hammerstein–Wiener model (HWM) and nonlinear autoregressive with exogenous inputs (NARX) network model. In terms of accuracy, the maximum error percentage of the proposed model is just 1.309%, far less than WM, HM and HWM. In terms of the stability of model calculation, the range of the mean error percentage of the proposed model is just a quarter of that of NARX network model.

The paper fulfills the construction of a novel multi-input nonlinear model, which has laid a foundation for the follow-up research of model-based GT fault detection and isolation or GT control.

Line–cell conversion and rotation of operators between cells are common in lean production systems. Thus, the purpose of this study is to provide an integrated look at these two practices through integrating job rotation scheduling and line-cell conversion problems, as well as investigating the effect of rotation frequency on flow time of a Seru system.

First, a nonlinear integer programming model of job rotation scheduling problem and line–cell conversion problem (Seru-JRSP) was presented. Then, because Seru-JRSP is NP-hard, an efficient and effective invasive weed optimization (IWO) algorithm was developed. Exploration process of IWO was enhanced by enforcing two shake mechanisms.

Computations of various sample problems showed shorter flow time and less number of assigned operators in a Seru system scheduled through job rotation. Also, nonlinear behavior of flow time versus number of rotation periods was shown. It was demonstrated that, setting number of rotation frequency to one in line with the literature leads to inferior flow time. In addition, ability of developed algorithm to generate clusters of equivalent solutions in terms of flow time was shown.

In this research, integration of job rotation scheduling and line–cell conversion problems was introduced, considering lack of an integrated look at these two practices in the literature. In addition, a new improved IWO equipped with shake enforcement was introduced.

This paper deals with a systematic approach for deriving an object based information model for CIM systems. Owing to the complex nature of CIM environment it is often difficult to identify data structures and functionality of such a system. An object based modeling methodology is presented, along with clustering based procedure for deriving a static structure model from functional requirements. Performance measures for evaluating the “quality” of the derived model are presented and discussed. A sample manufacturing application is provided in order to illustrate the approach.

The performance of cellular manufacturing (CM) systems has been rigorously investigated during the last two decades. The findings from these studies need to be systematically tabulated, given that they span a wide range of systems and experimental conditions. Some of the findings have also not been in agreement with the prescriptive literature on group technology (GT). No such survey of research exists to date. Attempts to fill the void by providing a taxonomy that categorizes these studies into simulation‐based, analytical and empirical studies. Also discusses past work in the context of various experimental factors and conditions, such as system configurations assumed, setup and operation times, scheduling rules, lot sizes and performance measures used. Summarizes major findings from each stream of literature from the point of view of both researchers and practitioners.

Development of a flexible medium technology assembly machine, the Microbot, and a link‐up with Montech has strengthened Aylesbury Automations assembly systems building abilities. Brian Rooks reports.

The conditioning of the redundancy equations is discussed and a method is given for drastically reducing any serious coupling between primary redundancies originating at the same ring station. Making use of the latent root programme of the computer, a revised transformation matrix, for the definition of the primary redundancies, is developed for the specific cross‐sectional shape and geometry when this is markedly non‐circular. The method is illustrated by application to a number of sample cases. Coupling between redundancies at different ring stations is also discussed, but is not considered to be serious except with unusual patterns of frame flexibility.

The purpose of this paper is to disclose a novel reconfiguration battery design suitable for electrically powered UAVs.

A design of a reconfigurable battery module is presented. Test setup with prototype battery module is developed and described. Test results of measurements are shown and discussed.

The results ascertain the benefits of implementing a reconfigurable battery in small electrically powered UAVs and specifically prove the efficiency of the proposed design.

The proposed novel design is compared to previous work while advances from the latter and the gained advantages were established.

The aim of this paper is to investigate how enterprise resource planning (ERP) systems could create a competitive advantage for small and medium‐sized enterprises (SMEs). The objectives of this study are to examine how responsive and agile the existing ERP systems are to change and uncertainty, and to identify the types of change and uncertainty in SME manufacturing environments.

A mixed methodology is used in this study, which involves literature review, questionnaire survey and follow‐up, in‐depth telephone interviews. An uncertainty diagnosing business model is applied to collect data from SME manufacturers in make‐to‐stock (MTS), make‐to‐order (MTO) and mixed mode (MM) manufacturing environments in a structured manner, and to analyse the effects of the underlying causes of uncertainty on product late delivery in MTS, MTO and MM manufacturing environments in SMEs. Some 108 enterprises responded (86 per cent response rate), of which 64 are SMEs. Analysis of variance (ANOVA) is carried out in SPSS to analyse the effects of the underlying causes of uncertainty on product late delivery in MTS, MTO and MM manufacturing environments in SMEs.

ANOVA results show that a different group of underlying causes of uncertainty significantly affects the product late delivery performance in MTS, MTO and MM manufacturing environments in SMEs. This study found that ERP could improve responsiveness and agility to change, but not to uncertainty. SMEs could create a competitive advantage by being more responsive to change in the ERP system before generating purchase and work order. ERP systems could not deal with uncertainty due to its stochastic and unpredictable nature. SMEs use a range of buffering or dampening techniques under uncertainty to be competitive in delivery.

It can be concluded that the application of the business model in SMEs that use ERP has provided useful knowledge about the significant underlying causes of uncertainty that affect product late delivery performance in MTS, MTO and MM manufacturing environments. Using this knowledge, similar SMEs could then prioritise the effort and devise suitable buffering or dampening techniques to manage the causes of uncertainty and hence prevent any changes to the ERP system.