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Book part
Publication date: 17 November 2003

Bradley D. Childs

The results of this study indicate that a likely reason why a negative relation between estimated implicit taxes and pretax returns is empirically observed is the researcher’s…

Abstract

The results of this study indicate that a likely reason why a negative relation between estimated implicit taxes and pretax returns is empirically observed is the researcher’s election to choose a zero tax rate as the benchmark state and local tax rate. Normally, an observed negative relation between estimated implicit taxes and pretax returns supports the hypothesis generated by implicit tax theory. This conclusion regarding the implicit tax hypothesis may be premature whenever the incidence of state and local income taxes contributes to this empirical finding. First, state income taxes, treated as a negative subsidy when the benchmark state and local tax rate is set at zero, will likely cause implicit taxes to be underestimated. Second, the observed relationship between estimated implicit taxes and pretax returns appears to be reversible depending upon the researcher’s election of a statutory tax rate that incorporates the selected benchmark state and local tax rate.

The present study uses a sample of 848 firms covering the years from 1989 through 1998 to show how the relation between estimated implicit taxes and pretax returns can be manipulated by the selection of the benchmark state and local tax rate. Since choosing an accurate benchmark state and local tax rate can be problematic, the present study suggests adjusting both estimated implicit taxes and pretax income by the amount of state and local income taxes incurred. The results, using the regression model making this adjustment, appear to nullify the negative bias of a zero tax rate as the benchmark state and local tax rate.

Details

Advances in Taxation
Type: Book
ISBN: 978-0-76231-065-4

Book part
Publication date: 29 October 2018

Yulia V. Ragulina, Leonid F. Malinovski, Yuliya A. Agunovich, Larisa A. Kapustyan and Oksana M. Zaryankina

The purpose of this chapter is to develop criteria of effectiveness of state management of the process of implementing the information economy’s optimization model, determine the…

Abstract

Purpose

The purpose of this chapter is to develop criteria of effectiveness of state management of the process of implementing the information economy’s optimization model, determine the corresponding indicators, and offer the method of evaluation of the effectiveness of state management of the process of implementing the information economy’s optimization model.

Methodology

This research applies the methods of induction, deduction, structural and functional analysis, and graphical presentation of information.

Results

Based on the peculiarities of the information economy’s optimization model, three main criteria of the effectiveness of state management while implementing this model are distinguished: flexibility of the normative and legal provision of information economy; balance of the level and rate of development of the noosphere components; and success of the protection, usage, and preservation of information’s uniqueness. To distinguish these criteria it is offered to evaluate the effectiveness of state management of the process of implementation of the information economy’s optimization model by progressive comparison of the sum of results with the sum of limitations and costs for each direction of state management of the process of implementation of the information economy’s optimization model, related to the provision of observation of the above criteria. The author determines the indicators that conform to the offered criteria of effectiveness of state management of the process of implementation of the information economy’s optimization model systematized in connection to these criteria, and offers the formula for calculating the final indicator of the effectiveness of state management of the process of implementation of the information economy’s optimization model.

Recommendations

The offered criteria of effectiveness of state management of the process of implementing the information economy’s optimization model, the corresponding indicators, and the compiled methodology of evaluating the effectiveness of this process are recommended for usage as methodological provision of monitoring and control of implementation of the information economy’s optimization model.

Article
Publication date: 9 May 2024

Yunshil Cha, Catherine Plante and Linda Ragland

In this study, we examine regulated public accessibility to municipalities’ financial reports and bond interest cost. In particular, we examine whether there is information…

Abstract

Purpose

In this study, we examine regulated public accessibility to municipalities’ financial reports and bond interest cost. In particular, we examine whether there is information content in a component of a constrained filing period that is useful to municipal bond market participants. The component of a filing period that we focus on is the period of time between an audit report date and a regulated public accessibility date.

Design/methodology/approach

To explore our research question, we collect a sample of observations from municipalities that: (1) are required to post annual/audit financial reports on a centralized state-level repository that includes a “transparent” date stamp on when reports are made publicly available and (2) have issued general obligation bonds. Our sample is limited to one observation per municipality. The sample period is 2006–2019. In terms of approach, we use an ordinary least square (OLS) regression model to empirically test whether the time period between municipalities’ audit report date and state-required repository filing date is associated with general obligation bond interest cost.

Findings

We find support for the idea that there is information content in a component of a constrained filing period. In particular, we hypothesize and find a positive association between the time period between an audit report date and a state filing date and general obligation bond interest cost. Seemingly, this component of time may provide something unique or not available in other components of a constrained filing period (e.g. the fiscal year-end date to the audit report date). In post hoc analyses, we also find that both components of the constrained filing period in our setting (i.e. the audit report date to state filing date and the fiscal year-end date to audit report date) need to be considered for either of the components to be significant. Moreover, although both components are necessary, the audit report date to state filing date component appears to have a slightly stronger association (in terms of statistical significance) with general obligation bond interest costs.

Research limitations/implications

To our knowledge, Illinois is the only state that provides a date stamp on when municipalities’ financial information is made publicly available on a centralized repository. As such we focus on municipalities in Illinois. While this increases the internal validity of our research, it potentially limits generalizability across other states. Also, as a reflection of the sample constraint, the number of observations in our study is relatively small. As part of post hoc analyses, we take a closer look at our sample, model and variables used to test our hypothesis.

Practical implications

For stakeholders, each component of a constrained filing period may provide unique information. For example, the time period between an audit report date and a regulated filing date may send a positive signal about the quality of financial management to investors. For regulators, requiring some sort of centralized public access to municipal financial reports that have transparent time constraints may help states provide stronger governance and help lower municipalities’ borrowing costs.

Originality/value

We use a novel approach (with the Illinois date stamp filing information) to examine our research question. Most prior research has often relied on an assumption that the time between fiscal year-end and the audit report date is the component of time that provides useful information to investors (e.g. Henke and Maher, 2016). In our setting, we explore and find that a component of a constrained filing time period (i.e. the date from an audit filing to a required public accessibility filing) may also provide impactful information to investors.

Details

Journal of Public Budgeting, Accounting & Financial Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1096-3367

Keywords

Article
Publication date: 9 May 2024

Abdulmenan Hamza

This study examines the impacts of the Ethiopian developmental state model on the competition, efficiency and profitability of banks.

Abstract

Purpose

This study examines the impacts of the Ethiopian developmental state model on the competition, efficiency and profitability of banks.

Design/methodology/approach

The competition, efficiency and profitability of the Ethiopian bank are measured using Panzar Rose, data envelopment analysis and financial ratio. Fixed-effect panel regression methods are applied to test the direction and strength of association between the Ethiopian developmental state model and the competition, efficiency and profitability of the country's banks while controlling bank-specific market structure and macroeconomic factors.

Findings

The Ethiopian developmental state model embeds the state-directed financial system, which affects the banking industry using a range of credit allocation instruments. Of which, directed credit schemes, interest rate control and the lack of financial freedom reduce the competition and efficiency of banks. The National Bank of Ethiopia (NBE) advances to the government and the sale of Treasury bills to a captive market enhances banking competition while negatively affecting banking efficiency. Interest rate control and the lack of financial freedom lower banking profitability. Unexpectedly, directed credit schemes improve banking profitability.

Research limitations/implications

As with any study, this one has limitations. The intra-period comparison of efficiency is based on balanced data. Future studies can use methods that can measure the efficiency of banks using unbalanced data. The computation of the yearly H-statistic is constrained by the small sample size. The use of high-frequency data for measuring competition can provide us with better insights into banking competition in Ethiopia. Furthermore, there are a number of methods for measuring banking competition, efficiency and profitability with different assumptions. Approaching the subject of this study by applying different methods will offer different insights.

Practical implications

The contributions of this study to practice are at two levels. First, at the policy level, it enhances our understanding of the impacts of developmental state model policies, as implemented in Ethiopia, on the banking industry and therefore provides suggestions to policymakers to reform the sector's policies. Second, it offers input to the management of banks regarding the factors that impact the industry.

Originality/value

The banking industry is often studied in the context of financial liberalisation. The originality of this study lies in investigating how the competition, efficiency and profitability of banks are affected when operating in the context of significant state interventions in the industry.

Details

African Journal of Economic and Management Studies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-0705

Keywords

Article
Publication date: 2 May 2024

Anjaly A. and Nemat Sheereen S.

The present study examines the effect of supervisor incivility on service employee creativity and the mediating mechanism of negative affect state on the said relationship with…

Abstract

Purpose

The present study examines the effect of supervisor incivility on service employee creativity and the mediating mechanism of negative affect state on the said relationship with the aid of Affective Events Theory (AET) and Social Power Theory. Additionally, the study explores the mitigating role of core self-evaluation in the dual stage of the moderated mediation model.

Design/methodology/approach

Survey data were collected from 420 frontline employees working in four-star and five-star hotels across India and PROCESS macro in SPSS 23.0 was employed to test the hypotheses proposed in the study.

Findings

The study findings observe that frontline employees experiencing supervisor incivility face a negative affect state and it further diminishes service employee creativity. Also, the indirect effect gets attenuated at dual stages when frontline employees are equipped with a high level of core self-evaluation.

Practical implications

The study findings provide various insights to the managers to understand the deleterious effect of supervisor incivility at work and to develop interventions to manage supervisor incivility and the negative affect state among frontline hotel employees.

Originality/value

The present study is the first and unique attempt to investigate the role of supervisor incivility experienced by frontline hotel employees in India with reference to their creativity towards customers and mediating mechanism of negative affect state. The study adds value to the literature by establishing the role of core self-evaluation in the moderated mediation model. Further, the study also provides a unique contribution to the management of frontline hospitality employees.

Details

Asia-Pacific Journal of Business Administration, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-4323

Keywords

Article
Publication date: 2 May 2024

Gerasimos G. Rigatos

To provide high torques needed to move a robot’s links, electric actuators are followed by a transmission system with a high transmission rate. For instance, gear ratios of 100:1…

Abstract

Purpose

To provide high torques needed to move a robot’s links, electric actuators are followed by a transmission system with a high transmission rate. For instance, gear ratios of 100:1 are often used in the joints of a robotic manipulator. This results into an actuator with large mechanical impedance (also known as nonback-drivable actuator). This in turn generates high contact forces when collision of the robotic mechanism occur and can cause humans’ injury. Another disadvantage of electric actuators is that they can exhibit overheating when constant torques have to be provided. Comparing to electric actuators, pneumatic actuators have promising properties for robotic applications, due to their low weight, simple mechanical design, low cost and good power-to-weight ratio. Electropneumatically actuated robots usually have better friction properties. Moreover, because of low mechanical impedance, pneumatic robots can provide moderate interaction forces which is important for robotic surgery and rehabilitation tasks. Pneumatic actuators are also well suited for exoskeleton robots. Actuation in exoskeletons should have a fast and accurate response. While electric motors come against high mechanical impedance and the risk of causing injuries, pneumatic actuators exhibit forces and torques which stay within moderate variation ranges. Besides, unlike direct current electric motors, pneumatic actuators have an improved weight-to-power ratio and avoid overheating problems.

Design/methodology/approach

The aim of this paper is to analyze a nonlinear optimal control method for electropneumatically actuated robots. A two-link robotic exoskeleton with electropneumatic actuators is considered as a case study. The associated nonlinear and multivariable state-space model is formulated and its differential flatness properties are proven. The dynamic model of the electropneumatic robot is linearized at each sampling instance with the use of first-order Taylor series expansion and through the computation of the associated Jacobian matrices. Within each sampling period, the time-varying linearization point is defined by the present value of the robot’s state vector and by the last sampled value of the control inputs vector. An H-infinity controller is designed for the linearized model of the robot aiming at solving the related optimal control problem under model uncertainties and external perturbations. An algebraic Riccati equation is solved at each time-step of the control method to obtain the stabilizing feedback gains of the H-infinity controller. Through Lyapunov stability analysis, it is proven that the robot’s control scheme satisfies the H-infinity tracking performance conditions which indicate the robustness properties of the control method. Moreover, global asymptotic stability is proven for the control loop. The method achieves fast convergence of the robot’s state variables to the associated reference trajectories, and despite strong nonlinearities in the robot’s dynamics, it keeps moderate the variations of the control inputs.

Findings

In this paper, a novel solution has been proposed for the nonlinear optimal control problem of robotic exoskeletons with electropneumatic actuators. As a case study, the dynamic model of a two-link lower-limb robotic exoskeleton with electropneumatic actuators has been considered. The dynamic model of this robotic system undergoes first approximate linearization at each iteration of the control algorithm around a temporary operating point. Within each sampling period, this linearization point is defined by the present value of the robot’s state vector and by the last sampled value of the control inputs vector. The linearization process relies on first-order Taylor series expansion and on the computation of the associated Jacobian matrices. The modeling error which is due to the truncation of higher-order terms from the Taylor series is considered to be a perturbation which is asymptotically compensated by the robustness of the control algorithm. To stabilize the dynamics of the electropneumatically actuated robot and to achieve precise tracking of reference setpoints, an H-infinity (optimal) feedback controller is designed. Actually, the proposed H-infinity controller for the model of the two-link electropneumatically actuated exoskeleton achieves the solution of the associated optimal control problem under model uncertainty and external disturbances. This controller implements a min-max differential game taking place between: (i) the control inputs which try to minimize a cost function which comprises a quadratic term of the state vector’s tracking error and (ii) the model uncertainty and perturbation inputs which try to maximize this cost function. To select the stabilizing feedback gains of this H-infinity controller, an algebraic Riccati equation is being repetitively solved at each time-step of the control method. The global stability properties of the H-infinity control scheme are proven through Lyapunov analysis.

Research limitations/implications

Pneumatic actuators are characterized by high nonlinearities which are due to air compressibility, thermodynamics and valves behavior and thus pneumatic robots require elaborated nonlinear control schemes to ensure their fast and precise positioning. Among the control methods which have been applied to pneumatic robots, one can distinguish differential geometric approaches (Lie algebra-based control, differential flatness theory-based control, nonlinear model predictive control [NMPC], sliding-mode control, backstepping control and multiple models-based fuzzy control). Treating nonlinearities and fault tolerance issues in the control problem of robotic manipulators with electropneumatic actuators has been a nontrivial task.

Practical implications

The novelty of the proposed control method is outlined as follows: preceding results on the use of H-infinity control to nonlinear dynamical systems were limited to the case of affine-in-the-input systems with drift-only dynamics. These results considered that the control inputs gain matrix is not dependent on the values of the system’s state vector. Moreover, in these approaches the linearization was performed around points of the desirable trajectory, whereas in the present paper’s control method the linearization points are related with the value of the state vector at each sampling instance as well as with the last sampled value of the control inputs vector. The Riccati equation which has been proposed for computing the feedback gains of the controller is novel, so is the presented global stability proof through Lyapunov analysis. This paper’s scientific contribution is summarized as follows: (i) the presented nonlinear optimal control method has improved or equally satisfactory performance when compared against other nonlinear control schemes that one can consider for the dynamic model of robots with electropneumatic actuators (such as Lie algebra-based control, differential flatness theory-based control, nonlinear model-based predictive control, sliding-mode control and backstepping control), (ii) it achieves fast and accurate tracking of all reference setpoints, (iii) despite strong nonlinearities in the dynamic model of the robot, it keeps moderate the variations of the control inputs and (iv) unlike the aforementioned alternative control approaches, this paper’s method is the only one that achieves solution of the optimal control problem for electropneumatic robots.

Social implications

The use of electropneumatic actuation in robots exhibits certain advantages. These can be the improved weight-to-power ratio, the lower mechanical impedance and the avoidance of overheating. At the same time, precise positioning and accurate execution of tasks by electropneumatic robots requires the application of elaborated nonlinear control methods. In this paper, a new nonlinear optimal control method has been developed for electropneumatically actuated robots and has been specifically applied to the dynamic model of a two-link robotic exoskeleton. The benefit from using this paper’s results in industrial and biomedical applications is apparent.

Originality/value

A comparison of the proposed nonlinear optimal (H-infinity) control method against other linear and nonlinear control schemes for electropneumatically actuated robots shows the following: (1) Unlike global linearization-based control approaches, such as Lie algebra-based control and differential flatness theory-based control, the optimal control approach does not rely on complicated transformations (diffeomorphisms) of the system’s state variables. Besides, the computed control inputs are applied directly on the initial nonlinear model of the electropneumatic robot and not on its linearized equivalent. The inverse transformations which are met in global linearization-based control are avoided and consequently one does not come against the related singularity problems. (2) Unlike model predictive control (MPC) and NMPC, the proposed control method is of proven global stability. It is known that MPC is a linear control approach that if applied to the nonlinear dynamics of the electropneumatic robot, the stability of the control loop will be lost. Besides, in NMPC the convergence of its iterative search for an optimum depends on initialization and parameter values selection and consequently the global stability of this control method cannot be always assured. (3) Unlike sliding-mode control and backstepping control, the proposed optimal control method does not require the state-space description of the system to be found in a specific form. About sliding-mode control, it is known that when the controlled system is not found in the input-output linearized form the definition of the sliding surface can be an intuitive procedure. About backstepping control, it is known that it cannot be directly applied to a dynamical system if the related state-space model is not found in the triangular (backstepping integral) form. (4) Unlike PID control, the proposed nonlinear optimal control method is of proven global stability, the selection of the controller’s parameters does not rely on a heuristic tuning procedure, and the stability of the control loop is assured in the case of changes of operating points. (5) Unlike multiple local models-based control, the nonlinear optimal control method uses only one linearization point and needs the solution of only one Riccati equation so as to compute the stabilizing feedback gains of the controller. Consequently, in terms of computation load the proposed control method for the electropneumatic actuator’s dynamics is much more efficient.

Details

Robotic Intelligence and Automation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 2 May 2024

Rafael Borim-de-Souza, Eric Ford Travis, Beatriz Lima Zanoni, Pablo Henrique Paschoal Capucho and Jacques Haruo Fukushigue Jan-Chiba

Through Bourdieusian sociology, this study aims to interpret a globalized symbolic environment ward by the States and dominated by organizations through the States’ Nobilities…

Abstract

Purpose

Through Bourdieusian sociology, this study aims to interpret a globalized symbolic environment ward by the States and dominated by organizations through the States’ Nobilities enticing and the Euro-American influences disseminated by the cultural circuit of capitalism in the inculcation and incorporation of a class habitus conniving with this logic of domination.

Design/methodology/approach

This study has developed a theoretical essay based on the contributions of Bourdieusian sociology to discuss and understand the following concepts and their respective relationships: symbolic environment, globalization, organizations, State, State Nobility, Euro-American influences, cultural circuit of capitalism and class habitus.

Findings

The arguments built throughout this theoretical essay recognized how class habitus on environment contributes to organizations establishing themselves as a space that consolidates and replicates the domination logic. As indicated, the State Nobility is an intermediary element between dominant organizations and the State, as dominated.

Practical implications

This theoretical essay signals that less harmful alliances between organizations, the State Nobility and the State could culminate in social, environmental and economic scenarios provided with more inclusion, diversity and preservation.

Social implications

This study presents an in-depth conceptual analysis to hold power structures responsible as direct and indirect drivers of environmental problems, with their different proportions and severity levels, affecting the planet.

Originality/value

This study proposes an alternative lens to debate and question how much the results presented by the contemporary world order compensate (if in any way) the damage that invades and deteriorate environmental assets.

Details

Journal of Global Responsibility, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2041-2568

Keywords

Article
Publication date: 9 May 2024

Ali Doğan and Mehmet Erçek

Building on previous historical works, this study aims to develop a framework to represent chambers as meta-organizations and present the case of Dersaadet Chamber of Commerce…

Abstract

Purpose

Building on previous historical works, this study aims to develop a framework to represent chambers as meta-organizations and present the case of Dersaadet Chamber of Commerce (DCC), based on this framework, during its emergence and evolution in the late 19th and early 20th centuries.

Design/methodology/approach

In the study, a historical narrative was constructed from primary and secondary data. To complement data collected from the archives a systematic content analysis was used to explore the discourse of the chamber within its serial magazine.

Findings

It was found that the first chamber of the Ottoman Empire, DCC, was established according to the public law model as an extension of the economic context and the guild order, and it was observed that it increasingly conformed to this model between 1882 and 1929.

Originality/value

In this study, chamber models are examined for the first time according to the designated features of meta-organizational forms, built on the historical work on chambers. The case of DCC suggested that it adopted a public law model and displayed much continuity, even when significant transitions were observed during the modernization process from Ottoman Empire to Turkish Republic.

Details

Journal of Management History, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1751-1348

Keywords

Open Access
Article
Publication date: 30 April 2024

Laura Curran and Jennifer Manuel

This study aims to examine the relationship between medication for opioid use disorder (MOUD) among pregnant individuals, referral source, mental health, political affiliation and…

Abstract

Purpose

This study aims to examine the relationship between medication for opioid use disorder (MOUD) among pregnant individuals, referral source, mental health, political affiliation and substance use policies in all 50 states in the USA.

Design/methodology/approach

This study describes MOUD receipt among pregnant people with an opioid use disorder (OUD) in 2018. The authors explored sociodemographic differences in MOUD receipt, referrals and co-occurring mental health disorders. The authors included a comparison of MOUD receipt among states that have varying substance use policies and examined the impact of these policies and the political affiliation on MOUD. The authors used multilevel binary logistic regression to examine effects of individual and state-level characteristics on MOUD.

Findings

Among 8,790 pregnant admissions with OUD, the majority who received MOUD occurred in the Northeast region (71.52%), and 14.99% were referred by the criminal justice system (n = 1,318). Of those who were self-referred, 66.39% received MOUD, while only 30.8% of referrals from the criminal justice system received MOUD. Those referred from the criminal justice system or who had a co-occurring mental health disorder were least likely to receive MOUD. The multilevel model showed that while policies were not a significant predictor, a state’s political affiliation was a significant predictor of MOUD.

Research limitations/implications

The study has some methodological limitations; a state-level analysis, even when considering the individual factors, may not provide sufficient description of community-level or other social factors that may influence MOUD receipt. This study adds to the growing literature on the ineffectiveness of prenatal substance use policies designed specifically to increase the use of MOUD. If such policies are consistently assessed as not contributing to substantial increase in MOUD among pregnant women over time, it is imperative to investigate potential mechanisms in these policies that may not facilitate MOUD access the way they are intended to.

Practical implications

Findings from this study aid in understanding the impact that a political affiliation may have on treatment access; states that leaned more Democratic were more likely to have higher rates of MOUD, and this finding can lead to research that focuses on how and why this contributes to greater treatment utilization. This study provides estimates of underutilization at a state level and the mechanisms that act as barriers, which is a stronger assessment of how state-specific policies and practices are performing in addressing prenatal substance use and a necessary step in implementing changes that can improve the links between pregnant women and MOUD.

Originality/value

To the best of the authors’ knowledge, this is the first study to explore individual-level factors that include mental health and referral sources to treatment that lead to MOUD use in the context of state-level policy and political environments. Most studies estimate national-level rates of treatment use only, which can be useful, but what is necessary is to understand what mechanisms are at work that vary by state. This study also found that while substance use policies were designed to increase MOUD for pregnant women, this was not as prominent a predictor as other factors, like mental health, being referred from the criminal justice system, and living in a state with more Democratic-leaning affiliations.

Details

Drugs, Habits and Social Policy, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2752-6739

Keywords

Article
Publication date: 15 April 2024

Xiaona Wang, Jiahao Chen and Hong Qiao

Limited by the types of sensors, the state information available for musculoskeletal robots with highly redundant, nonlinear muscles is often incomplete, which makes the control…

Abstract

Purpose

Limited by the types of sensors, the state information available for musculoskeletal robots with highly redundant, nonlinear muscles is often incomplete, which makes the control face a bottleneck problem. The aim of this paper is to design a method to improve the motion performance of musculoskeletal robots in partially observable scenarios, and to leverage the ontology knowledge to enhance the algorithm’s adaptability to musculoskeletal robots that have undergone changes.

Design/methodology/approach

A memory and attention-based reinforcement learning method is proposed for musculoskeletal robots with prior knowledge of muscle synergies. First, to deal with partially observed states available to musculoskeletal robots, a memory and attention-based network architecture is proposed for inferring more sufficient and intrinsic states. Second, inspired by muscle synergy hypothesis in neuroscience, prior knowledge of a musculoskeletal robot’s muscle synergies is embedded in network structure and reward shaping.

Findings

Based on systematic validation, it is found that the proposed method demonstrates superiority over the traditional twin delayed deep deterministic policy gradients (TD3) algorithm. A musculoskeletal robot with highly redundant, nonlinear muscles is adopted to implement goal-directed tasks. In the case of 21-dimensional states, the learning efficiency and accuracy are significantly improved compared with the traditional TD3 algorithm; in the case of 13-dimensional states without velocities and information from the end effector, the traditional TD3 is unable to complete the reaching tasks, while the proposed method breaks through this bottleneck problem.

Originality/value

In this paper, a novel memory and attention-based reinforcement learning method with prior knowledge of muscle synergies is proposed for musculoskeletal robots to deal with partially observable scenarios. Compared with the existing methods, the proposed method effectively improves the performance. Furthermore, this paper promotes the fusion of neuroscience and robotics.

Details

Robotic Intelligence and Automation, vol. 44 no. 2
Type: Research Article
ISSN: 2754-6969

Keywords

1 – 10 of over 366000