15 resultados para conditions of employment
em Aston University Research Archive
Resumo:
The effects of antioxidants and stabilizers on the oxidative degradation of polyolefins (low density polyethylene [LDPE] and polypropylene [PPJ have been studied after subjecting to prior high temperature processing treatments. The changes in the both chemical and physical properties of unstabilized polymers occurring during processing were found to be strongly dependent on the amount of oxygen present in the mixer. Subsequent thermal and photo-oxidation showed very similar characteristics and the chromophore primarily responsible for:both thermo and photooxidative degradation of unstabilized polymers was found to be hydroperoxide formed during processing. Removal of hydroperoxide by heat treatment in an inert atmosphere although increasing ketonic carbonyl concentration, markedly decreased the rate of photo-oxidation, introducing an induction period similar to that of an unprocessed sample. It was concluded that hydroperoxides are the most important initiators in normally processed polymers during the early stages of photo-oxidation. Antioxidants such as metal dithiocarbamates which act by destroying peroxides into non-radica1 products were found to be efficient melt stabilizers for polyolefins and effective UV stabilizers during the initial photo-oxidation stage, whilst a phenolic antioxidant, n-octadecyl-3-(3',5'-di-terbutyl 4'hydroxypheny1) propionate (Irganox 1076) retarded photo-oxidation rate in the later stages. A typical 'UV absorber' 2-hydroxy-4-octyloxy-benzophenone (HOBP) has a minor thermal antioxidant action but retarded photo-oxidation at all stages. A substituated piperidine derivative, Bis [2.2.6.6-tetramethylpiperidlnyl-4] sebacate (Tinuvin 770) behaved as an pro-oxidant during thermal oxidation of polyolefins but was an effective stabilizer against UV light. The UV absorber, HOBP synergised effectively with both peroxide decomposing antioxidants (metal dithiocarbamates) and a chain-breaking antioxidant (Irganox 1076) during photo-oxidation of the poymers studed whereas the combined effect was additive during thermal oxidation. By contrast, the peroxide decornposers and chain-breaking antioxidant (Irganox 1076) which were effective synergists during thermal oxidation of LDPE· were antagonistic during photo-oxidation. The mechanisms of these processes are discussed.
Resumo:
This thesis deals with the integration of the manpower criterion with the strategic decision making processes of technological projects in developing countries. This integration is to be achieved by ensuring the involvement of the actors, who have relevant roles and responsibilities along the whole life cycle of the project, in the strategic decision making phases of the project. The relevance of the actors is ascertained by the use of a responsibility index which relates their responsibility to the project's constituent stages. In the context of a technological project in a typical centrally-planned developing environment, the actors are identified as Arbiters, Planners, Implementors and Operators and their roles, concerns and objectives are derived. In this context, the actors are usually government and non-government organisations. Hence, decision making will involve multiple agencies as well as multiple criteria. A methodology covering the whole decision-making process, from options generation to options selection, and adopting Saaty's Analytical Hierarchy Process as an operational tool is proposed to deal with such multiple-criteria, multipleagency decision situations. The methodology is intended to integrate the consideration of the relevant criteria, the prevailing environmental and policy factors, and the concerns and objectives of the relevant actors into a unifying decision-making process which strives to facilitate enlightened decision making and to enhance learning and interaction. An extensive assessment of the methodology's feasibility, based on a specific technological project within the Iraqi oil industry is included, and indicates that the methodology should be both useful and implementable.
Resumo:
This study has concentrated on the development of an impact simulation model for use at the sub-national level. The necessity for the development of this model was demonstrated by the growth of local economic initiatives during the 1970's, and the lack of monitoring and evaluation exercise to assess their success and cost-effectiveness. The first stage of research involved the confirmation that the potential for micro-economic and spatial initiatives existed. This was done by identifying the existence of involuntary structural unemployment. The second stage examined the range of employment policy options from the macroeconomic, micro-economic and spatial perspectives, and focused on the need for evaluation of those policies. The need for spatial impact evaluation exercise in respect of other exogenous shocks, and structural changes was also recognised. The final stage involved the investigation of current techniques of evaluation and their adaptation for the purpose in hand. This led to a recognition of a gap in the armoury of techniques. The employment-dependency model has been developed to fill that gap, providing a low-budget model, capable of implementation at the small area level and generating a vast array of industrially disaggregate data, in terms of employment, employment-income, profits, value-added and gross income, related to levels of United Kingdom final demand. Thus providing scope for a variety of impact simulation exercises.
Resumo:
Background Yellow filters are sometimes recommended to people with low vision. Our aim was investigate the effects of three commercial yellow filters on visual acuity and contrast sensitivity (with and without glare) and reading (without glare) under conditions of forward light scatter (FLS). Method Fifty-five healthy subjects were assessed with Corning Photochromic Filters (CPFs) 450, 511 and 527 and a filter producing FLS. The effects on log MAR visual acuity, Pelli–Robson contrast sensitivity with and without glare, and reading (measured with MNRead charts) without glare were determined. Results Statistically significant differences were found between the overall effect of glare and between CPFs for visual acuity and contrast sensitivity. A gradual decline in visual acuity, contrast sensitivity and reading with increasing CPF absorption was noted. Conclusion Effects of CPF450, 511, 527 on visual acuity, contrast sensitivity and reading under conditions of FLS were negative but not clinically significant.
Resumo:
Many foreign investment operations into emerging markets are small, and are likely to have only a limited impact on the local economy. However, host governments often expect transfer of advanced technology from multinational enterprises (MNEs) operating in these markets to local firms by way of inter-firm mobility of skilled labourers. The extent of such transfers would be limited, among other factors, by the size of the pool of skilled labourers that can potentially be mobile between MNEs and local firms. This, in turn, is determined by employment growth at the MNEs. We develop an empirical specification that models this employment growth, by drawing on both the economics and international business literature. This model is then estimated using firm-level data from four emerging markets. We find that wholly owned foreign direct investment operations have higher employment growth, while local industry and institutional characteristics moderate the growth effect. This suggests that policies encouraging foreign investors to set up in form of joint ventures may not actually raise the benefits for the host economy.
Resumo:
This paper proposes a new framework for evaluating the performance of employment offices based on non-parametric technique of data envelopment analysis. This framework is explained using the assessment of technical efficiency of 82 employment offices in Tunisia which are under the direction of the National Agency for Employment and Independent Work. We further investigated the exogenous factors that may explain part of the variation in efficiency scores using a bootstrapping approach in period January 2006 to December 2008. Given the specialisation of employment offices, we used the proposed approach for the efficiency evaluation of graduate employment offices and multi-services employment offices, separately.
Resumo:
The present study explores strategies used to legitimize the transfer of organizational practices in a situation of institutional upheaval. We apply the logic of social action (Risse, 2000) to analyze the effectiveness of consequence-based action and communication-based action, in terms of higher coordination, lower conflict, and overall higher economic performance. Consequence-based legitimation is obtained by using a system of distributor incentives tied to performance of specific tasks, while communicative legitimation can be achieved by recommendations and warnings. Our setting is an export channel to European emerging economies. Our results indicate that in the absence of legitimacy, as manifested in discretionary legal enforcement, consequence-based legitimation is more effective than communicative legitimation in reducing conflict, increasing coordination, and ultimately in improving the performance of the export dyad. © 2014 Elsevier Inc.
Resumo:
The effects of lipoic acid and dihydrolipoic acid were explored on total thiol maintenance in diabetic and non-diabetic human erythrocytes in vitro over 22 hr in a 37°C incubation system with no added glucose. Over 18-22.5 hr after treatment in both non-diabetic and diabetic cells, lipoic acid (1 mM) was associated with greater loss of cellular thiols than dihydrolipoic acid (1 mM), compared to respective control values. At 0.1 mM, in non-diabetic cells, although lipoic acid-treated cells' thiol levels were significantly lower than control, there was no significant difference between dihydrolipoic acid-treated cells and control cells regarding thiol levels. In addition, at 0.1 mM, dihydrolipoic acid-treated diabetic cells showed a reduction in thiol levels compared to control. At 0.01 mM, lipoic acid-treated cells had significantly lower measured thiol levels compared with diabetic cells exposed to dihydrolipoic acid, whereas in non-diabetic cells, dihydrolipoic acid-treated erythrocytic thiol levels were significantly greater than those treated with lipoic acid, although there were no other significant differences between the groups. At 22.5 hr, control values of methaemoglobin rose to 6.4 ± 1.1% in diabetic cells and 3.6 ± 2.1% in non-diabetic cells. Lipoic acid (1 mM) showed greater methaemoglobin formation in diabetic rather than non-diabetic cells (13.6 ± 1.5% versus 11.6 ± 1.5%), whereas dihydrolipoic acid-treated diabetic and non-diabetic cells were less potent in methaemoglobin generation (8.5 ± 2.4% and 8.4 ± 1.4%, respectively). These studies suggest that in certain circumstances such as hypoglycaemia, lipoic acid administration may actually be detrimental to cellular oxidant protection status. © 2006 The Authors.
Resumo:
The link between work and welfare is a key pathway of modern welfare state development in Western Europe. National governments face a constant balancing act between the welfare expectations of the labour forces and the labour market liberalisation demands of the business communities. Facilitating the transit from welfare into employment has therefore become an important tool for the British, German and Swedish governments, providing labour as and when needed while keeping welfare expenditure in check. However, the approaches to organising active labour market policies are quite different, notably with regard to the territorial dimension. Although labour markets are quite diverse in all three cases, the role of local authorities, local agencies and local labour market actors from the private and voluntary sector are generally under-developed and apparently under-appreciated, but in different ways and for different reasons. The article compares current employment-related welfare provisions and approaches to develop active labour market policies in the three countries, and concludes that while certain structural and procedural similarities exist, the basic political priorities and actual support and services provided remain very far apart.
Resumo:
The following thesis instigates the discussion on corporate social responsibility (CSR) through a review of literature on the conceptualisation, determinants, and remunerations of organisational CSR engagement. The case is made for the need to draw attention to the micro-levels of CSR, and consequently focus on employee social responsibility at multiple levels of analysis. In order to further research efforts in this area, the prerequisite of an employee social responsibility behavioural measurement tool is acknowledged. Accordingly, the subsequent chapters outline the process of scale development and validation, resulting in a robust, reliable and valid employee social responsibility scale. This scale is then put to use in a field study, and the noteworthy roles of the antecedent and boundary conditions of transformational leadership, assigned CSR priority, and CSR climate are confirmed at the group and individual level. Directionality of these relationships is subsequently alluded to in a time-lagged investigation, set within a simulated business environment. The thesis collates and discusses the contributions of the findings from the research series, which highlight a consistent three-way interaction effect of transformational leadership, assigned CSR priority and CSR climate. Specifically, efforts are made to outline various avenues for future research, given the infancy of the micro-level study of employee social responsibility.
Resumo:
Using data on Polish firms this paper examines the relationship between corporate control structures, sales growth and the determinants of employment change. Privatised and de novo firms are the main drivers of employment growth; in the case of de novo firms, it is foreign ownership which underpins the result. Being privatised has a positive impact on employment but this is concentrated within a range of 3–6 years after privatisation. There are no systematic differences in employment response to negative sales growth across the ownership categories. Employment in state firms is less responsive to positive sales growth. From these results we infer that the behaviour of state firms is affected by both insider rent sharing and binding budget constraints.
Resumo:
Using panel data on large Polish firms this paper examines the relationship between corporate control structures, sales growth and the determinants of employment change during the period 1996-2002. We find that privatised and de novo firms are the main drivers of employment growth and that, in the case of de novo firms, it is foreign ownership which underpins the result. Interestingly, we find that being privatised has a positive impact on employment growth but that this impact is concentrated within a range of three to six years after privatisation. In contrast with the findings of earlier literature, we find evidence that there are no systematic differences in employment response to negative sales growth across the ownership categories. On the other hand, employment in state firms is less responsive to positive sales growth. From these combined results we infer that the behaviour of state firms is constrained by both insider rent sharing and binding budget constraints. Consistent with this, we find that privatised companies, three to six years post-privatisation, are the firms for whom employment is most responsive to positive sales growth and as such, offer the best hope for rapid labour market expansion.
Resumo:
Over the past decade or so a number of changes have been observed in traditional Japanese employment relations (ERs) systems such as an increase in non-regular workers, a move towards performance-based systems and a continuous decline in union membership. There is a large body of Anglo-Saxon and Japanese literature providing evidence that national factors such as national institutions, national culture, and the business and economic environment have significantly influenced what were hitherto three ‘sacred’ aspects of Japanese ERs systems (ERSs). However, no research has been undertaken until now at the firm level regarding the extent to which changes in national factors influence ERSs across firms. This article develops a model to examine the impact of national factors on ER systems; and analyses the impact of national factors at the firm level ER systems. Based on information collected from two different groups of companies, namely Mitsubishi Chemical Group (MCG) and Federation of Shinkin Bank (FSB) the research finds that except for a few similarities, the impact of national factors is different on Japanese ER systems at the firm level. This indicates that the impact of national factors varies in the implementation of employment relations factors. In the case of MCG, national culture has less to do with seniority-based system. Study also reveals that the national culture factors have also less influence on an enterprise-based system in the case of FSB. This analysis is useful for domestic and international organizations as it helps to better understand the role of national factors in determining Japanese ERSs.
Resumo:
We studied the effects of the composition of impregnating solution and heat treatment conditions on the activity of catalytic systems for the low-temperature oxidation of CO obtained by the impregnation of Busofit carbon-fiber cloth with aqueous solutions of palladium, copper, and iron salts. The formation of an active phase in the synthesized catalysts at different stages of their preparation was examined with the use of differential thermal and thermogravimetric analyses, X-ray diffraction analysis, X-ray photoelectron spectroscopy, and elemental spectral analysis. The catalytic system prepared by the impregnation of electrochemically treated Busofit with the solutions of PdCl, FeCl, CuBr, and Cu(NO ) and activated under optimum conditions ensured 100% CO conversion under a respiratory regime at both low (0.03%) and high (0.5%) carbon monoxide contents of air. It was found that the activation of a catalytic system at elevated temperatures (170-180°C) leads to the conversion of Pd(II) into Pd(I), which was predominantly localized in a near-surface layer. The promoting action of copper nitrate consists in the formation of a crystalline phase of the rhombic atacamite CuCl(OH). The catalyst surface is finally formed under the conditions of a catalytic reaction, when a joint Pd(I)-Cu(I) active site is formed. © 2014 Pleiades Publishing, Ltd.