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To find a successful human action recognition system (HAR) for the unmanned environments.

This paper describes the key technology of an efficient HAR system. In this paper, the advancements for three key steps of the HAR system are presented to improve the accuracy of the existing HAR systems. The key steps are feature extraction, feature descriptor and action classification, which are implemented and analyzed. The usage of the implemented HAR system in the self-driving car is summarized. Finally, the results of the HAR system and other existing action recognition systems are compared.

This paper exhibits the proposed modification and improvements in the HAR system, namely the skeleton-based spatiotemporal interest points (STIP) feature and the improved discriminative sparse descriptor for the identified feature and the linear action classification.

The experiments are carried out on captured benchmark data sets and need to be analyzed in a real-time environment.

The middleware support between the proposed HAR system and the self-driven car system provides several other challenging opportunities in research.

The authors’ work provides the way to go a step ahead in machine vision especially in self-driving cars.

The method for extracting the new feature and constructing an improved discriminative sparse feature descriptor has been introduced.

This paper aims to propose a weld seam tracking method based on proximal policy optimization (PPO).

By constructing a neural network based on PPO and using the reference image block and the image block to be detected as the dual-channel input of the network, the method predicts the translation relation between the two images and corrects the location of feature points in the weld image. The localization accuracy estimation network (LAE-Net) is built to update the reference image block during the welding process, which is helpful to reduce the tracking error.

Off-line simulation results show that the proposed algorithm has strong robustness and performs well on the test set of curved seam images with strong noise. In the welding experiment, the movement of welding torch is stable, the molten material is uniform and smooth and the welding error is small, which can meet the requirements of industrial production.

The idea of image registration is applied to weld seam tracking, and the weld seam tracking network is built on the basis of PPO. In order to further improve the tracking accuracy, the LAE-Net is constructed and the reference images can be updated.

This work presents a topology optimization methodology for designing microarchitectures of phononic crystals. The objective is to get microstructures having, as a consequence of wave propagation phenomena in these media, bandgaps between two specified bands. An additional target is to enlarge the range of frequencies of these bandgaps.

The resulting optimization problem is solved employing an augmented Lagrangian technique based on the proximal point methods. The main primal variable of the Lagrangian function is the characteristic function determining the spatial geometrical arrangement of different phases within the unit cell of the phononic crystal. This characteristic function is defined in terms of a level-set function. Descent directions of the Lagrangian function are evaluated by using the topological derivatives of the eigenvalues obtained through the dispersion relation of the phononic crystal.

The description of the optimization algorithm is emphasized, and its intrinsic properties to attain adequate phononic crystal topologies are discussed. Particular attention is addressed to validate the analytical expressions of the topological derivative. Application examples for several cases are presented, and the numerical performance of the optimization algorithm for attaining the corresponding solutions is discussed.

The original contribution results in the description and numerical assessment of a topology optimization algorithm using the joint concepts of the level-set function and topological derivative to design phononic crystals.

This paper aims to propose a bilateral robotic system for lower extremity hemiparesis rehabilitation. The hemiplegic patients can complete rehabilitation exercise voluntarily with the assistance of the robot. The reinforcement learning is included in the robot control system, enhancing the muscle activation of the impaired limbs (ILs) efficiently with ensuring the patients’ safety.

A bilateral leader–follower robotic system is constructed for lower extremity hemiparesis rehabilitation, where the leader robot interacts with the healthy limb (HL) and the follow robot is worn by the IL. The therapeutic training is transferred from the HL to the IL with the assistance of the robot, and the IL follows the motion trajectory prescribed by the HL, which is called the mirror therapy. The model reference adaptive impedance control is used for the leader robot, and the reinforcement learning controller is designed for the follower robot. The reinforcement learning aims to increase the muscle activation of the IL and ensure that its motion can be mastered by the HL for safety. An asynchronous algorithm is designed by improving experience relay to run in parallel on multiple robotic platforms to reduce learning time.

Through clinical tests, the lower extremity hemiplegic patients can rehabilitate with high efficiency using the robotic system. Also, the proposed scheme outperforms other state-of-the-art methods in tracking performance, muscle activation, learning efficiency and rehabilitation efficacy.

Using the aimed robotic system, the lower extremity hemiplegic patients with different movement abilities can obtain better rehabilitation efficacy.

The purpose of this paper is to investigate by means of finite element analysis (FEA), the effect of polyethylene insert thickness and implant material, under axial loading following TKA.

The 3D geometric model of bone was processed using the CT scan data by MIMICS (3matic Inc.), package. Implant components were 3D scanned and subsequently 3D modeled using ANSYS Spaceclaim and meshed in Hypermesh (Altair Hyperworks). The assembled, meshed bone-implant model was then input to ABAQUS for FE simulations, considering axial loading.

Polyethylene insert thickness was found to have very little or no significance (p>0.05) on the mechanical performance, namely, stress, strain and stress shielding of bone-implant system. Implant material was found to have a very significant effect (p<0.05) on the performance parameters and greatly reduced the high stress zones up to 60 percent on the tibial flange region and periprosthetic region of tibia.

Very few FEA studies have been done considering a full bone with heterogeneous material properties, to save computational time. Moreover, four different polyethylene insert thickness with a metal-backed and all-poly tibial tray was considered as the variables affecting the bone-implant system response, under static axial loading. The authors believe that considering a full bone shall lead to more precise outcomes, in terms of the response of bone-implant system, namely, stress, strains and stress shielding in the periprosthetic region, to loading.

This study aims to understand the role of employee competencies in terms of the relationship between Human Resource Practices (HRPs) and firm performance.

A sample of 60 HR managers and 546 employees from large-scale food processing firms were considered for the study. The study presents a 2-1-2 multilevel mediational analysis in which HRPs and firm performance are measured at the firm level (Level-2) and employee competencies are measured at employee level (Level-1).

Positive relationship was found between HRPs and firm performance, which was partially mediated by employee competencies.

The study highlights the importance of employee-related factors by focusing on the wider dimensions of human capital (e.g. academic qualification, job experience) in HRPs–performance relationship.

The study undertakes a 2-1-2 multilevel mediational analysis, which is rarely applied in HRM studies; however, this interaction between macro- and microlevel effects will create a better understanding of organization studies from an integrated and multilevel context.

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.

Current criminological theory and the Government's focus on ‘community safety’ and ‘crime and disorder reduction’ has led to the creation of a new discipline, or at least a new paradigm, that of crime science. This article explores the theoretical basis and multi‐disciplinary nature of crime science and its usefulness in the reduction of alcohol and drug‐related crime.

Research focusing on the relation between market orientation and innovation in the Asian emerging economy is limited. The purpose of this study is to advance the extant literature by investigating the relations among market orientation, guanxi networking and innovation using the MARKOR scale.

The research conclusion is drawn based on the experience of 122 Asian emerging market firms operating in a wide variety of industrial sectors. This study explores whether the three MARKOR components (intelligence generation, dissemination and responsiveness) and their interaction with business and political guanxi have a significant effect on firms’ strategic innovation success. Innovation is measured following the practice of the OECD. In addition to the quantitative analyses, this study conducted qualitative interviews with executives of eight respondent firms, to further consolidate the subjects under investigation. The integration of both qualitative and quantitative data enriches the conclusions drawn from the study.

The findings of this study confirm that, when operating in an Asian emerging economy, both intelligence generation and responsiveness have a positive and direct impact on innovation. Though intelligence dissemination has no direct influence on innovation, its alignment with business and political guanxi still leads to a positive effect on innovation. The coalition of responsiveness and political guanxi, however, has a negative influence on innovation. The results of this study add new insights to the extant literature and provide implications for future research and marketing practices in Asian emerging economies.

The findings of this study confirm that, when operating in an Asian emerging economy, both intelligence generation and responsiveness have a positive and direct impact on innovation. Though intelligence dissemination has no direct influence on innovation, its alignment with business and political guanxi still leads to a positive effect on innovation. The coalition of responsiveness and political guanxi, however, has a negative influence on innovation. The results add new insights to the extant literature and provide implications for future research and marketing practices in Asian emerging economies.

Despite the concentrated study on turnover intention (TI), slightly is known on the subject in what manner work engagement intervenes the link connecting workplace bullying (WPB) and TI is varied across sectors, and how WPB and TI implications are viewed among academicians of public universities in Nigeria. The aim of this article is to explore in what way the association between WPB and TI is mediated by work engagement (WE) in public universities in Nigeria.

The paper applied judgmental sampling to gather 400 data from academic staff that must have worked for a minimum of six months in the current university. The present study used SmartPLS software 3.2.9 for the estimation of the hypothesis.

The result confirmed that work engagement intervenes the outcome of WPB and HRM on TI.

The current study presents validation for the mediating impact of work engagement on the relationships connecting WPB and HRM on TI in Nigeria universities. Outcomes from findings encompassing all employees in the universities and other service sectors would offer further significant and practical implications for administrators.

The research furthers our knowledge of the intervening effect of work engagement in the link among WPB and TI across academicians in public universities in Nigeria. To reduce turnover intention among academic staff, administrators must have a good insight into how WE mediates the correlation linking WPB and TI.