Search results

1 – 3 of 3
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 11 January 2008

William Owen, Elizabeth Croft and Beno Benhabib

Recent research has considered robotic machining as a dextrous alternative to traditional CNC machine tools for complex sculptured surfaces. One challenge in using robotic…

884

Abstract

Purpose

Recent research has considered robotic machining as a dextrous alternative to traditional CNC machine tools for complex sculptured surfaces. One challenge in using robotic machining is that the stiffness is lower than traditional machine tools, due to the cantilever design of the links and low‐torsional stiffness of the actuators. This paper seeks to examine this limitation, using optimization algorithms to determine the best trajectories for the manipulators such that the stiffness is maximized.

Design/methodology/approach

The issue of low stiffness is addressed with an integrated off‐line planner and real‐time re‐planner. The available manipulator stiffness is maximized during off‐line planning through a trajectory resolution method that exploits the nullspace of the robot machining system. In response to unmodeled disturbances, a real‐time trajectory re‐planner utilizes a time‐scaling method to reduce the tool speed, thereby reducing the demand on the actuator torques, increasing the robot's dynamic stiffness capabilities. During real‐time re‐planning, priorities are assigned to conflicting performance criteria such as stiffness, collision avoidance, and joint limits.

Findings

The algorithms developed were able to generate trajectories with stiffer configurations, which resulted in a reduction in the actuator torques. The real‐time re‐planner successfully allowed the process plan to continue when disturbances were encountered.

Research limitations/implications

Simulations are presented to demonstrate the effectiveness of the approach.

Practical implications

Addressing the limitation of stiffness in serial‐link manipulators will enable robots to become more suitable for machining tasks. The real‐time re‐planning approach will allow robots to become more autonomous during the execution of a given task.

Originality/value

An integrated off‐line and real‐time planning approach has been applied to robotic machining.

Details

Industrial Robot: An International Journal, vol. 35 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

Access Restricted. View access options
Article
Publication date: 30 June 2022

Verena Tandrayen Ragoobur and Jason Narsoo

The paper investigates into the human capital–economic growth nexus by arguing that investment in early education and health helps in achieving higher economic growth. Early…

384

Abstract

Purpose

The paper investigates into the human capital–economic growth nexus by arguing that investment in early education and health helps in achieving higher economic growth. Early investment in human capital matters most for economic growth than the increase in human capital over the years.

Design/methodology/approach

A dynamic vector error correction model (VECM) together with the impulse response function and variance decomposition are used on data for Mauritius from 1983 to 2019. The paper distinguishes between the short-run and the long-run effects of human capital measured by the pupil–teacher ratio in pre-primary education and life expectancy at birth.

Findings

This study’s findings reveal that investment in early education and health has contributed positively to growth performance. There is evidence for long-run growth effects arising from a positive shock in the education and health indicators.

Originality/value

This paper contributes to both the theoretical and empirical literature on the human capital–growth nexus. Mauritius as a natural resource poor small economy is an important case study as it has started early in investing in its people to promote economic growth.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-11-2021-0674.

Details

International Journal of Social Economics, vol. 49 no. 11
Type: Research Article
ISSN: 0306-8293

Keywords

Access Restricted. View access options
Article
Publication date: 25 February 2020

Driss El Kadiri Boutchich

This work aims to propose an alternative method of human capital calculation for research laboratories of public university, taking into account some drawbacks of the methods…

98

Abstract

Purpose

This work aims to propose an alternative method of human capital calculation for research laboratories of public university, taking into account some drawbacks of the methods currently applied in this field.

Design/methodology/approach

This method is implemented via a linear program extracted from Data Envelopment Analysis based on slack movement. This is the formulation of Copper et al. (2000), which is used as the starting point for developing the proposed method through important transformations.

Findings

The proposed method is supported by an illustration related to a Moroccan public university. This illustration showed that 57 per cent of the laboratories and all the research activities that they perform are in deficit with respect to target scores.

Research limitations/implications

The proposed method has technical limitations related to scores equal to 1 and to variables when those are numerous. To solve them, it is possible to use peer benchmarking system for the first limitation, and methods of regrouping the variables when those are numerous for the second limitation. Equally, the proposed method does not associate slack with important factors like governance and the impact analysis of research on innovation, competitiveness, and societal aspects. Likewise, it does not use the slack to measure individual efficiency at the same laboratory. Future research can fill these gaps.

Practical implications

This work allows making appropriate budgetary and research policy within university, through budgeting process and management control by using raw and adjusted target values as well as actual ones. Also, the highlighting of the excessive slacks leads the university to take actions to reduce them, according to the most loss-making research activities.

Originality/value

The proposed method is original, since it fills a deficit in terms of human capital target values calculation and of the slack movement concept in relation to the efficient frontier. Additionally, it transforms the Data Envelopment Analysis program into a program that eliminates the slacks linked to the inputs, the radial movement related to the outputs and treats only the outputs and slacks related to these outputs.

1 – 3 of 3
Per page
102050