907 resultados para 280109 Decision Support and Group Support Systems


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This introduction essay proposes a challenging program for researchers eager to explore factors and process mechanisms contributing to the benefits and costs individuals and groups incur from pursuing innovative approaches. With respect to individual innovation, such moderating factors might be found in the characteristics of the innovative idea, the innovator, co-workers, supervisors, the broader organizational context, and in national culture. Examples of factors that are likely to shape the beneficial and detrimental outcomes of group innovation include knowledge, skills and ability of group members, group tenure, diversity among group members, group processes (clarifying group objectives, participation, constructive management of competing perspectives), and external demands on groups. This Special Issue contains a state-of-the-science paper, three articles dealing with the benefits and costs of individual innovation, and three articles addressing the bright and dark sides of group innovation. Copyright © 2004 John Wiley & Sons, Ltd.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We compare the Q parameter obtained from scalar, semi-analytical and full vector models for realistic transmission systems. One set of systems is operated in the linear regime, while another is using solitons at high peak power. We report in detail on the different results obtained for the same system using different models. Polarisation mode dispersion is also taken into account and a novel method to average Q parameters over several independent simulation runs is described. © 2006 Elsevier B.V. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We compare the Q parameter obtained from the semi-analytical model with scalar and vector models for two realistic transmission systems. First a linear system with a compensated dispersion map and second a soliton transmission system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This chapter discusses the current state of biomass-based combined heat and power (CHP) production in the UK. It presents an overview of the UK's energy policy and targets which are relevant to the deployment of biomass-based CHP and summarises the current state for renewable, biomass and CHP. A number of small-scale biomass-based CHP projects are described while providing some indicative capital costs for combustion, pyrolysis and gasification technologies. For comparison purposes, it presents an overview of the respective situation in Europe and particularly in Sweden, Finland and Denmark. There is also a brief comment about novel CHP technologies in Austria. Finally it draws some conclusions on the potential of small-scale biomass CHP in the UK. © 2011 Woodhead Publishing Limited All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A vertical pin on horizontal disc machine has been used to conduct a series of experiments in air under dry and lubricating sliding conditions. For dry sliding low load and speed combinations were chosen to correspond to the mild wear region below the Welsh T1 transition. Lubricated tests were conducted under flooded conditions using Esso Technical White Oil alone and with a 0.1% stearic acid additive, for load and speed ranges that produced substantial amounts of asperity contact and thus a boundary lubricated regime of wear. The test material in all cases was AISI 52100 steel, for unlubricated sliding subjected to loads from 5 to 50 N and a range of speeds from 10-3 to 1.0 ms-1, and for lubricated sliding loads of 50 to 123 N and for speeds of 10-2 to 1.0 ms-1. Unlubricated wear debris was found to be a mixture of -Fe_2O_3 and -Fe. Unlubricated wear was found to occur via a thin film logarithmic oxide growth followed by agglomeration into thicker oxide plateaux 2 to 10 m in thickness. Lubricated wear occurred via thick film diffusion controlled oxide growth producing homogeneous oxide plateaux 0.1 to 0.2 m in thickness. X-ray photoelectron spectroscopy identified the presence of a surface film on pins worn in White Oil with stearic acid, which is thought to be iron stearate. A model has been developed for unlubricated wear based upon the postulated growth of thin film oxides by a logarithmic rate law. The importance of sliding geometry and environment to the dominant wear mechanism has been illustrated.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The two areas of theory upon which this research was based were „strategy development process?(SDP) and „complex adaptive systems? (CAS), as part of complexity theory, focused on human social organisations. The literature reviewed showed that there is a paucity of empirical work and theory in the overlap of the two areas, providing an opportunity for contributions to knowledge in each area of theory, and for practitioners. An inductive approach was adopted for this research, in an effort to discover new insights to the focus area of study. It was undertaken from within an interpretivist paradigm, and based on a novel conceptual framework. The organisationally intimate nature of the research topic, and the researcher?s circumstances required a research design that was both in-depth and long term. The result was a single, exploratory, case study, which included use of data from 44 in-depth, semi-structured interviews, from 36 people, involving all the top management team members and significant other staff members; observations, rumour and grapevine (ORG) data; and archive data, over a 5½ year period (2005 – 2010). Findings confirm the validity of the conceptual framework, and that complex adaptive systems theory has potential to extend strategy development process theory. It has shown how and why the strategy process developed in the case study organisation by providing deeper insights to the behaviour of the people, their backgrounds, and interactions. Broad predictions of the „latent strategy development? process and some elements of the strategy content are also possible. Based on this research, it is possible to extend the utility of the SDP model by including peoples? behavioural characteristics within the organisation, via complex adaptive systems theory. Further research is recommended to test limits of the application of the conceptual framework and improve its efficacy with more organisations across a variety of sectors.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Road traffic accident involvement rates show that younger males are over represented in accidents. A number of studies have shown individual differences in accident involvement. Questionnaire-based methods to investigate individual and group differences in driver stress and risk perceptions reported in chapter 2 and 3 revealed that neuroticism was associated with; heightened perception of personal risk, driver stress, and inefficient coping strategies. Younger drivers and female drivers reported higher levels of stress. Young male drivers assessed their personal risk and driving abilities less realistically than did other age and sex groups. Driving simulator-based methods reported in chapter 4 revealed that young drivers and male drivers; drive faster, overtake more often, and commit more `high risk' overtakes than do other age and sex groups. Middle-aged and elderly drivers were poorer at maintaining a fixed distance from a lead `vehicle'. Older drivers adopt a slower, more cautious driving style, but appear to be worse at controlling distance from a `lead' vehicle. Results are consistent with individual and group differences in accident involvement rates. Findings are discussed with reference to the implementation of driver education programs to reduce stress, the adoption of more realistic perceptions of risk among younger drivers, and the training of compensation strategies to counteract age-related changes in older drivers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This research compares U.S. and Japanese management systems and evaluates their transferability to the Singaporean manufacturing industry. The objectives were:- a) To determine the effectiveness of U.S. and Japanese management systems when applied to Singapore. b) Determine the extent of transferability of U.S. and Japanese management systems to Singapore. c) Survey general problems ecountered in the application of U.S. and Japanese management systems to the Singapore industry. The study using questionnaire survey and interviews covered a total of eighty companies from four groups of firms in four industrial sectors comprising of U.S. and Japanese subsidiaries based in Singapore and their respective parent companies. Data from the questionnaires and interviews were used to investigate environmental conditions, management philosophy, management functions/practices, management effectiveness, and firm productivity. Two-way analysis of variance was used to analyse the questionnaire data. The analysis of the perceptual data from the questionnaire survey and interviews suggested that both U.S. and Japanese parent companies performed better in almost all the management variables studied when compared to their subsidiaries in Singapore. U.S. subsidiaries have less difficulty in adjusting to the Singapore environmental conditions and obtained better results than the Japanese subsidiaries in management functions/practices and management philosophy than the U.S. subsidiaries. In addition, the firm productivity (in terms of labour and capital productivity) of U.S. subsidiaries in Singapore was found to be higher than those of the Japanese subsidiaries. It was found that the Japanese parent companies returned the highest score among the four groups of firms in all the four industrial sectors for all the four management variables (i.e. environmental conditions, management philosophy, management functions/practices, and management effectiveness) surveyed using questionnaires. In contrast, the average score for Japanese subsidiaries in Singapore was generally the lowest among the four groups of firms. Thus the results of this study suggest that the transfer of U.S. management system into the Singapore industry is more successful than the Japanese management system. The problems encountered in the application of U.S. and Japanese management in Singapore were identified and discussed by the study. General recommendations for the Singaporean manufacturing industry were then made based on the findings of the questionnaire survey and interview analysis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Alginate is widely used as a viscosity enhancer in many different pharmaceutical formulations. The aim of this thesis is to quantitatively describe the functions of this polyelectrolyte in pharmaceutical systems. To do this the techniques used were Viscometry, Light Scattering, Continuous and Oscillatory Shear Rheometry, Numerical Analysis and Diffusion. Molecular characterization of the Alginate was carried out using Viscometry and Light Scattering to determine the molecular weight, the radius of gyration, the second virial coefficient and the Kuhn statistical segment length. The results showed good agreement with similar parameters obtained in previous studies. By blending Alginate with other polyelectrolytes, Xanthan Gum and 'Carbopol', in various proportions and with various methods of low and high shear preparation, a very wide range of dynamic rheological properties was found. Using oscillatory testing, the parameters often varied over several decades of magnitude. It was shown that the determination of the viscous and elastic components is particularly useful in describing the rheological 'profiles' of suspending agent blends and provides a step towards the non-empirical formulation of pharmaceutical disperse systems. Using numerical analysis of equations describing planar diffusion, it was shown that the analysis of drug release profiles alone does not provide unambiguous information about the mechanism of rate control. These principles were applied to the diffusion of Ibuprofen in Calcium Alginate gels. For diffusion in such non-Newtonian systems, emphasis was placed on the use of the elastic as well as the viscous component of viscoelasticity. It was found that the diffusion coefficients were relatively unaffected by increases in polymer concentration up to 5 per cent, yet the elasticities measured by oscillatory shear rheometry were increased. This was interpreted in the light of several theories of diffusion in gels.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The effects of haem limitation and iron restriction on cells of non typable Haemophilus influenzae were investigated. Haem limitation was achieved by adding concentrations of haem to growth media which resulted in substantial decreases in final cell yields. Iron restriction was achieved by substituting protoporphyrin IX (PPIX) for haem in the growth medium and adding an iron chelator to the system. The effect of these nutrient limitations on a) outer membrane composition, and b) respiratory systems of non typable H.influenzae was investigated. Several of the strains examined produced new PPIX-specific outer membrane proteins when cultured utilising PPIX as a porphyrin source. The immune response of patients with bronchiectasis to outer membrane antigens of H.influenzae cultured under iron-restricted conditions was analysed by ELISA and immunoblotting techniques. ELISA analysis revealed that individuals with severe bronchiectasis had high titres of antibodies directed against H.influenzae OMs in both serum and sputum. Immunoblotting with homologous serum showed that where PPIX-specific OMPs were produced they were antigenic and were recognised by patients' serum. This suggested that these H.influenzae OMPs may be expressed in vivo. Additionally, the development of the immune responses to non typable H.influenzae outer membrane antigens was investigated using a rat lung model. Bacteria encased in agar beads were inoculated intratracheally into rat lungs, infection was established, and the immune response monitored for 6 weeks. The animals developed antibodies to PPIX-specific OMPs during the course of infection, providing further evidence that H.influenzae express these novel OMP antigens when growing in vivo. Studies in vitro on respiratory systems of phenotypically altered H.influenzae showed that bacteria grown utilising PPIX as a porphyrin source, or under conditions of iron-restriction produced ten fold fewer cytochromes than cells grown in nutrient excess, while haem limited H.influenzae produced no detectable cytochromes. Respiration of various substrates was depressed in haem limited and in PPIX-grown cultures as compared with cells grown in nutrient excess.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The specific objective of the research was to evaluate proprietary audit systems. Proprietary audit systems comprise question sets containing approximately 500 questions dealing with selected aspects of health and safety management. Each question is allotted a number of points and an organisation seeks to judge its health and safety performance by the overall score achieved in the audit. Initially it was considered that the evaluation method might involve comparing the proprietary audit scores with other methods of measuring safety performance. However, what appeared to be missing in the first instance was information that organisations could use to compare the contrast question set content against their own needs. A technique was developed using the computer database FileMaker Pro. This enables questions in an audit to be sorted into categories using a process of searching for key words. Questions that are not categorised by word searching can be identified and sorted manually. The process can be completed in 2-3 hours which is considerably faster than manual categorisation of questions which typically takes about 10 days. The technique was used to compare and contrast three proprietary audits: ISRS, CHASE and QSA. Differences and similarities between these audits were successfully identified. It was concluded that in general proprietary audits need to focus to a greater extent on identifying strengths and weaknesses in occupational health and safety management systems. To do this requires the inclusion of more probing questions which consider whether risk control measures are likely to be successful.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Multiple-antenna systems offer significant performance enhancement and will be applied to the next generation broadband wireless communications. This thesis presents the investigations of multiple-antenna systems – multiple-input multiple-output (MIMO) and cooperative communication (CC) – and their performances in more realistic propagation environments than those reported previously. For MIMO systems, the investigations are conducted via theoretical modelling and simulations in a double-scattering environment. The results show that the variations of system performances depend on how scatterer density varies in flat fading channels, and that in frequency-selective fading channels system performances are affected by the length of the coding block as well as scatterer density. In realistic propagation environments, the fading correlation also has an impact on CC systems where the antennas can be further apart than those in MIMO systems. A general stochastic model is applied to studying the effects of fading correlation on the performances of CC systems. This model reflects the asymmetry fact of the wireless channels in a CC system. The results demonstrate the varied effects of fading correlation under different protocols and channel conditions. Performances of CC systems are further studied at the packet level, using both simulations and an experimental testbed. The results obtained have verified various performance trade-offs of the cooperative relaying network (CRN) investigated in different propagation environments. The results suggest that a proper selection of the relaying algorithms and other techniques can meet the requirements of quality of service for different applications.