5 resultados para ROTATIONAL ANALYSIS
em Deakin Research Online - Australia
Resumo:
Purpose – The aim of this paper is to provide a critical evaluation of the potential of new institutional economics (NIE) in third world development.
Design/methodology/approach – The paper reviews various theories under NIE from both conceptual and empirical perspectives. It then reviews the various definitions of institutions and show that institutions are essential to overcome problems of information and uncertainty.
Findings – The review finds that weak institutions can undermine development and hence governments in developing countries should strengthen their institutions to provide greater scope for efficient functioning of markets. Where the market does not work owing to high transactions costs, traditional institutions of collective action and group decision making can work and hence need to be recognised.
Research limitations/implications – The major implications of the paper is that in developing countries, a clear understanding of various institutions such as user groups, inter-linked credit markets, rotational irrigation etc. is needed before they are replaced or modified by other institutions. The main limitations of NIE are that there can be capture by elites of various institutional innovations in rural areas, and that it does not explicitly consider income distribution and uncertainty which are glossed over and hence remain areas for future research.
Originality/value – This paper critically reviews the various institutional environments that developing countries face in addressing development issues.
Resumo:
The paper introduces four families of three-DOFs translational-rotational Parallel-Kinematics Mechanisms (PKMs) as well as the mobility analysis of such families using Lie group theory. Two of these families are mechanisms with one-rotational two-translational degrees of freedom (DOFs) and each of the other two has one-translational two-rotational DOFs. Four novel mechanisms are presented and discussed as representatives of these four families. Although these mechanisms are asymmetric, the components used to realise them are very similar and, hence, there is no great departure from the favourable modularity of parallel-kinematics mechanisms.
Resumo:
The paper introduces a family of three-DOFs translational-rotational Parallel-Kinematics Mechanisms (PKMs) as well as the mobility analysis of such family using Lie-group theory. Each member of this family has two-rotational one-translational DOFs. A novel mechanism is presented and analyzed as a representative of that family. The use and the practical value of that modular mechanism are emphasized.
Resumo:
The recent successful development of the equal channel angular pressing (ECAP) process in metals provides a feasible solution to produce ultra-fine or nano-grained bulk: materials with tailored material properties. However, ECAP is difficult to scale up commercially due to excessive load requirements. In this paper, a new Multi-ECAP process with die rotation is considered to obtain ultra-fine grain structured materials under a moderate deformation force. It is shown that an addition of torsion results in a reduction in the pressing force and an increase in severity of plastic deformation. An analysis using the upper bound method is found to be useful in predicting the pressing load and flow pattern of ECAP with and without rotational dies. Solutions are obtained for different inclined channel angles under different angular velocities of dies. Relative pressures are presented and some computed solutions are compared with those found by FEM simulation. The theoretical predictions of the pressing load are in good agreement with the simulation results. The amount of plastic deformation is determined by the inclined angle between the two intersecting channels, and the velocity ratio between the angular velocity of dies and the normal component of the punch velocity.
Resumo:
Thermal analysis, impedance spectroscopy, NMR and Raman spectroscopy have been used to investigate the plastic crystal dimethylpyrrolidinium thiocyanate in order to gain further insight into the properties of organic ionic plastic crystals. This compound has a solid–solid phase transition at 82 °C, and melts at 122 °C. A step increase in conductivity of about one order of magnitude is observed at the phase transition, followed by a decrease in activation energy for conduction. A large entropy gain occurs at the II → I transition, and 1H NMR linewidth measurements together with second moment calculations showed that the dimethylpyrrolidinium cation goes from a static state, to full isotropic tumbling. Raman measurements confirm that the cation as well as the anion exhibit increased rotational mobility when entering phase I.