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The authors describe an automatic system to measure the repeatability of industrial robots. A unit with a resolution of 11µm and an accuracy as high as 0.5µm has been designed.
T. Yan, B.E. Jones, R.T. Rakowski, M.J. Tudor, S.P. Beeby and N.M. White
This paper reports on a novel load cell and a novel torque transducer having stiffness and potential overload capability some ten times that of existing load cells and torque…
Abstract
Purpose
This paper reports on a novel load cell and a novel torque transducer having stiffness and potential overload capability some ten times that of existing load cells and torque transducers based on the resistance strain gauges.
Design/methodology/approach
Describes the practical capabilities and technology – the design, construction and characterisation.
Findings
Both the load cell and the torque transducer use recently developed metallic triple beam resonators with thick‐film lead zirconate titanate (PZT) drives and pickups. The advantages of this technology are frequency output, high overload capability, high sensitivity, high resolution, and low‐cost manufacture. Both the load cell and torque transducer output large changes in frequency (>500 Hz for relatively low changes in strain level i.e. <200 microstrain for the load cell and <400 microstrain for the torque transducer), providing high sensitivity and high overload capability.
Practical implications
Load cells and torque transducers employing the new metallic resonators are expected to be far more robust than those using metallic resistance strain gauges.
Originality/value
Focuses on an instrument with important features of use in many applications.
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Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…
Abstract
Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.
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Zouheir Malki, Daoud Ait-Kadi and Mohamed-Salah Ouali
The purpose of this paper is to investigate age replacement policies for two-component parallel system with stochastic dependence. The stochastic dependence considered, is modeled…
Abstract
Purpose
The purpose of this paper is to investigate age replacement policies for two-component parallel system with stochastic dependence. The stochastic dependence considered, is modeled by a one-sided domino effect. The failure of component 1 at instant t may induce the failure of component 2 at instant t+τ with probability p 1→2. The time delay τ is a random variable with known probability density function h p 1→2 (.). The system is considered in a failed state when both components are failed. The proposed replacement policies suggest to replace the system upon failure or at age T whichever occurs first.
Design/methodology/approach
In the first policy, costs and durations associated with maintenance activities are supposed to be constant. In the second replacement policy, the preventive replacement cost depends on the system’s state and age. The expected cost per unit of time over an infinite span is derived and numerical examples are presented.
Findings
In this paper and especially in the second policy, the authors find that the authors can get a more economical policy if the authors consider that the preventive replacement cost is not constant but depends on T.
Originality/value
In this paper, the authors take into account of the stochastic dependence between system components. This dependence affects the global reliability of the system and replacement’s periodicity. It can be used to measure the performance of the system et introduced into design phase of the system.
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– The purpose of this paper is to analyze investor reactions to ethical screening by pension plan managers.
Abstract
Purpose
The purpose of this paper is to analyze investor reactions to ethical screening by pension plan managers.
Design/methodology/approach
The author presents a sample consisting of data corresponding to 573 pension plans in relation to such aspects as financial performance, inception date, asset size, number of participants, custodial and management fees, and whether their managers adopt ethical screening or give part of their profits to social projects. On this data the author implements the fixed effects panel data model proposed by Vogelsang (2012).
Findings
The results obtained indicate that investors/consumers prefer traditional or solidarity pension plans to ethical pension plans. Furthermore, the findings show that ethical investors/consumers are more (less) sensitive to positive (negative) lagged returns than caring and traditional consumers, causing traditional consumers to contribute to pension plans that they already own.
Research limitations/implications
The author does not know what types of environmental, social and corporate governance criteria have been adopted by ethical pension plan managers and the weight given to each of these criteria for selecting the stock of the firms in their portfolios that could influence in the investors’ behaviour.
Practical implications
The results obtained in the current paper show that investors invest less money in ethical pension plans than in traditional and solidarity pension plans; this could be due to the lack of information for their part. To solve this, management companies could increase the transparency about their corporate social responsibility (CSR) investments to encourage investors to invest in ethical products so these lead to raising CSR standards in companies, and therefore, sustainable development.
Social implications
The Spanish socially responsible investment retail market is still at an early phase of development, and regulators should promote it in order to encourage firms to adopt business activities that take into account societal concerns.
Originality/value
This paper provides new evidence in a field little analysed. This paper contributes to the existing literature by focusing on examining the behaviour of pension funds investors whose investment time horizon is in the long-term while previous literature focus on analysing behaviour of mutual fund investors whose investment time horizon is in the short/medium term what could cause different investors’ behaviour.
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Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely…
Abstract
Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.
An economic leader in the Caribbean, the Republic of Trinidad and Tobago has incorporated micro‐business development as one of its main strategies to alleviate poverty and…
Abstract
An economic leader in the Caribbean, the Republic of Trinidad and Tobago has incorporated micro‐business development as one of its main strategies to alleviate poverty and unemployment and to spawn economic growth since the late 1980s. Although the discovery of natural gas in the early nineties catapulted Trinidad’s economic growth rate to four per cent per annum, unemployment and poverty continue to affect a large portion of the population. The majority of the population has not benefited from Trinidad’s economic growth. Thus, the government has attempted to create “a nation of entrepreneurs” in order to relieve some of the inequality that defines the society (Ministry of Trade and Industry 1997).
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