Verification of design calculations of a wind catcher/tower natural ventilation system with performance testing in real building

A wind catcher/tower natural ventilation system was installed in a seminar room in the building of the School of Construction Management and Engineering, the University of Reading in the UK . Performance was analysed by means of ventilation tracer gas measurements, indoor climate measurements (temperature, humidity, CO2) and occupant surveys. In addition, the potential of simple design tools was evaluated by comparing observed ventilation results with those predicted by an explicit ventilation model and the AIDA implicit ventilation model. To support this analysis, external climate parameters (wind speed and direction, solar radiation, external temperature and humidity) were also monitored. The results showed the chosen ventilation design provided a substantially greater ventilation rate than an equivalent area of openable window. Also air quality parameters stayed within accepted norms while occupants expressed general satisfaction with the system and with comfort conditions. Night cooling was maximised by using the system in combination with openable windows. Comparisons of calculations with ventilation rate measurements showed that while AIDA gave reasonably correlated results with the monitored performance results, the widely used industry explicit model was found to over estimate the monitored ventilation rate.

Synapsing variable length crossover: An algorithm for crossing and comparing variable length genomes

The Synapsing Variable Length Crossover (SVLC) algorithm provides a biologically inspired method for performing meaningful crossover between variable length genomes. In addition to providing a rationale for variable length crossover it also provides a genotypic similarity metric for variable length genomes enabling standard niche formation techniques to be used with variable length genomes. Unlike other variable length crossover techniques which consider genomes to be rigid inflexible arrays and where some or all of the crossover points are randomly selected, the SVLC algorithm considers genomes to be flexible and chooses non-random crossover points based on the common parental sequence similarity. The SVLC Algorithm recurrently "glues" or synapses homogenous genetic sub-sequences together. This is done in such a way that common parental sequences are automatically preserved in the offspring with only the genetic differences being exchanged or removed, independent of the length of such differences. In a variable length test problem the SVLC algorithm is shown to outperform current variable length crossover techniques. The SVLC algorithm is also shown to work in a more realistic robot neural network controller evolution application.

Synapsing variable-length crossover: Meaningful crossover for variable-length genomes

The synapsing variable-length crossover (SVLC algorithm provides a biologically inspired method for performing meaningful crossover between variable-length genomes. In addition to providing a rationale for variable-length crossover, it also provides a genotypic similarity metric for variable-length genomes, enabling standard niche formation techniques to be used with variable-length genomes. Unlike other variable-length crossover techniques which consider genomes to be rigid inflexible arrays and where some or all of the crossover points are randomly selected, the SVLC algorithm considers genomes to be flexible and chooses non-random crossover points based on the common parental sequence similarity. The SVLC algorithm recurrently "glues" or synapses homogenous genetic subsequences together. This is done in such a way that common parental sequences are automatically preserved in the offspring with only the genetic differences being exchanged or removed, independent of the length of such differences. In a variable-length test problem, the SVLC algorithm compares favorably with current variable-length crossover techniques. The variable-length approach is further advocated by demonstrating how a variable-length genetic algorithm (GA) can obtain a high fitness solution in fewer iterations than a traditional fixed-length GA in a two-dimensional vector approximation task.

Stars in their eyes: what eye-tracking reveal about multimedia perceptual quality

Perceptual multimedia quality is of paramount importance to the continued take-up and proliferation of multimedia applications: users will not use and pay for applications if they are perceived to be of low quality. Whilst traditionally distributed multimedia quality has been characterised by Quality of Service (QoS) parameters, these neglect the user perspective of the issue of quality. In order to redress this shortcoming, we characterise the user multimedia perspective using the Quality of Perception (QoP) metric, which encompasses not only a user’s satisfaction with the quality of a multimedia presentation, but also his/her ability to analyse, synthesise and assimilate informational content of multimedia. In recognition of the fact that monitoring eye movements offers insights into visual perception, as well as the associated attention mechanisms and cognitive processes, this paper reports on the results of a study investigating the impact of differing multimedia presentation frame rates on user QoP and eye path data. Our results show that provision of higher frame rates, usually assumed to provide better multimedia presentation quality, do not significantly impact upon the median coordinate value of eye path data. Moreover, higher frame rates do not significantly increase level of participant information assimilation, although they do significantly improve overall user enjoyment and quality perception of the multimedia content being shown.

An analytical model of mountain wave drag for wind profiles with shear and curvature

An analytical model is developed to predict the surface drag exerted by internal gravity waves on an isolated axisymmetric mountain over which there is a stratified flow with a velocity profile that varies relatively slowly with height. The model is linear with respect to the perturbations induced by the mountain, and solves the Taylor–Goldstein equation with variable coefficients using a Wentzel–Kramers–Brillouin (WKB) approximation, formally valid for high Richardson numbers, Ri. The WKB solution is extended to a higher order than in previous studies, enabling a rigorous treatment of the effects of shear and curvature of the wind profile on the surface drag. In the hydrostatic approximation, closed formulas for the drag are derived for generic wind profiles, where the relative magnitude of the corrections to the leading-order drag (valid for a constant wind profile) does not depend on the detailed shape of the orography. The drag is found to vary proportionally to Ri21, decreasing as Ri decreases for a wind that varies linearly with height, and increasing as Ri decreases for a wind that rotates with height maintaining its magnitude. In these two cases the surface drag is predicted to be aligned with the surface wind. When one of the wind components varies linearly with height and the other is constant, the surface drag is misaligned with the surface wind, especially for relatively small Ri. All these results are shown to be in fairly good agreement with numerical simulations of mesoscale nonhydrostatic models, for high and even moderate values of Ri.

Post-occupancy evaluation studies in recently refurbished office building: energy performance and employees' satisfaction

Existing buildings contribute greatly to global energy use and greenhouse gas emissions. In the UK, about 18% of carbon emissions are generated by non-domestic buildings; sustainable building refurbishment can play an important role in reducing carbon emissions. This paper looks at the performance of a recently refurbished 5-storey office building in London, in terms of energy consumption as well as occupants’ satisfaction. Pre- and post-occupancy evaluation studies were conducted using online questionnaire surveys and energy consumption evaluation. Results from pre-occupancy and post-occupancy evaluation studies showed that employees, in general, were more satisfied with their work environment at the refurbished building than with that of their previous office. Employees’ self-reported productivity improved after the move to Elms House. These surveys showed a positive relationship between employees’ satisfaction with their work environment and their self-reported productivity, well-being and enjoyment at work. The factor that contributed to increasing employee satisfaction the most was: better use of interior space. Although the refurbishment was a success in terms of reducing energy consumption per m2, the performance gap was almost 3 times greater than that estimated. Unregulated loads, problems with building control, ineffective use of space and occupants’ behaviour are argued to be reasons for this gap.

Post-occupancy studies of an office environment: Energy performance and occupants’ satisfaction

It is generally accepted that the physical workplace environment affects employees’ satisfaction and, consequently, their perceived productivity and well-being. This study investigated whether employee “satisfaction” variables can predict perceived productivity, well-being and enjoyment at work, and if so, to what extent. The study also explored whether limiting employees’ control over their environment could save energy without compromising employees’ satisfaction and perceived productivity. Preoccupancy and post-occupancy evaluation studies were conducted, in terms of both energy consumption and employee perceptions, to make comparisons between a company’s old and current headquarters buildings, both located in the same area of London. The results showed that employees were more satisfied with their work environment at their new HQ, in general, than with that of their previous office. Also, employees’ self-reported productivity, well-being and enjoyment at work improved after the move. It was revealed that the combination of employees’ level of satisfaction with “interior use of space” and “physical conditions” was the best predictor of their perceived productivity, while satisfaction with “indoor facilities” was not a good predictor. In terms of energy performance, although the new HQ’s energy consumption per m2 was significantly less than that of the previous building, there was still a gap between the refurbishment design target and the actual performance of the building. The findings suggest that this gap could be due to a number of factors, including an ineffective use of interior space, and occupants’ behaviour.

Complex dynamics in simple systems with periodic parameter oscillations

We study systems with periodically oscillating parameters that can give way to complex periodic or nonperiodic orbits. Performing the long time limit, we can define ergodic averages such as Lyapunov exponents, where a negative maximal Lyapunov exponent corresponds to a stable periodic orbit. By this, extremely complicated periodic orbits composed of contracting and expanding phases appear in a natural way. Employing the technique of ϵ-uncertain points, we find that values of the control parameters supporting such periodic motion are densely embedded in a set of values for which the motion is chaotic. When a tiny amount of noise is coupled to the system, dynamics with positive and with negative nontrivial Lyapunov exponents are indistinguishable. We discuss two physical systems, an oscillatory flow inside a duct and a dripping faucet with variable water supply, where such a mechanism seems to be responsible for a complicated alternation of laminar and turbulent phases.

Distinct clinical and neuropathological features of G51D SNCA mutation cases compared with SNCA duplication and H50Q mutation

Background: We and others have described the neurodegenerative disorder caused by G51D SNCA mutation which shares characteristics of Parkinson’s disease (PD) and multiple system atrophy (MSA). The objective of this investigation was to extend the description of the clinical and neuropathological hallmarks of G51D mutant SNCA-associated disease by the study of two additional cases from a further G51D SNCA kindred and to compare the features of this group with a SNCA duplication case and a H50Q SNCA mutation case. Results: All three G51D patients were clinically characterised by parkinsonism, dementia, visual hallucinations, autonomic dysfunction and pyramidal signs with variable age at disease onset and levodopa response. The H50Q SNCA mutation case had a clinical picture that mimicked late-onset idiopathic PD with a good and sustained levodopa response. The SNCA duplication case presented with a clinical phenotype of frontotemporal dementia with marked behavioural changes, pyramidal signs, postural hypotension and transiently levodopa responsive parkinsonism. Detailed post-mortem neuropathological analysis was performed in all cases. All three G51D cases had abundant α-synuclein pathology with characteristics of both PD and MSA. These included widespread cortical and subcortical neuronal α-synuclein inclusions together with small numbers of inclusions resembling glial cytoplasmic inclusions (GCIs) in oligodendrocytes. In contrast the H50Q and SNCA duplication cases, had α-synuclein pathology resembling idiopathic PD without GCIs. Phosphorylated α-synuclein was present in all inclusions types in G51D cases but was more restricted in SNCA duplication and H50Q mutation. Inclusions were also immunoreactive for the 5G4 antibody indicating their highly aggregated and likely fibrillar state. Conclusions: Our characterisation of the clinical and neuropathological features of the present small series of G51D SNCA mutation cases should aid the recognition of this clinico-pathological entity. The neuropathological features of these cases consistently share characteristics of PD and MSA and are distinct from PD patients carrying the H50Q or SNCA duplication.

Determinants of satisfaction amongst tenants of UK Offices

Purpose – Corporate Occupiers require offices and services which meet their business needs, whilst landlords must attract and retain occupiers in order to maximise occupancy and rental income. The purpose of this research is to help landlords and corporate occupiers understand each other better, in order to achieve a mutually beneficial relationship. Design/methodology/approach - This paper analyses interviews with 1334 office tenants in the UK, conducted over an 11-year period, to investigate determinants of occupier satisfaction, loyalty and advocacy. Structural equation modelling and regressions are performed using respondents’ ratings of satisfaction with many aspects of occupancy as explanatory variables. The dependent variables include satisfaction with property management, value for money, overall occupier satisfaction, lease renewal intentions and occupiers’ willingness to recommend their landlord. Findings - The aspects with most impact on occupiers’ satisfaction are the office building itself, its location and amenities, and also communication with their property manager, a belief that their business needs are understood and the property manager’s responsiveness to occupiers’ requests. Occupiers’ loyalty depends mainly upon feeling that their rent and service charges provide value for money, an amicable leasing process, the professionalism of their property manager and the Corporate Social Responsibility of the Landlord. ‘Empathy’ is crucial to occupiers’ willingness to recommend their landlord, and clear documentation and efficient legal process improve occupiers’ perception of receiving ‘Value for Money’. Research Limitations - The sample is skewed towards occupiers of prime office buildings in the UK, owned by landlords who care sufficiently about their tenants to commission studies into occupier satisfaction. Practical implications - This research should help to improve the landlord – tenant relationship, benefitting the businesses that rent property and helping building managers understand where to focus their efforts to achieve maximum effect on occupier satisfaction, loyalty and advocacy. Originality/value - There has been little academic research into the determinants of satisfaction of occupiers of UK commercial property. This large-scale study enables the most influential factors to be identified and prioritised.

The impact of variable sea ice roughness on changes in Arctic Ocean surface stress: a model study

The Arctic sea ice cover is thinning and retreating, causing changes in surface roughness that in turn modify the momentum flux from the atmosphere through the ice into the ocean. New model simulations comprising variable sea ice drag coefficients for both the air and water interface demonstrate that the heterogeneity in sea ice surface roughness significantly impacts the spatial distribution and trends of ocean surface stress during the last decades. Simulations with constant sea ice drag coefficients as used in most climate models show an increase in annual mean ocean surface stress (0.003 N/m2 per decade, 4.6%) due to the reduction of ice thickness leading to a weakening of the ice and accelerated ice drift. In contrast, with variable drag coefficients our simulations show annual mean ocean surface stress is declining at a rate of -0.002 N/m2 per decade (3.1%) over the period 1980-2013 because of a significant reduction in surface roughness associated with an increasingly thinner and younger sea ice cover. The effectiveness of sea ice in transferring momentum does not only depend on its resistive strength against the wind forcing but is also set by its top and bottom surface roughness varying with ice types and ice conditions. This reveals the need to account for sea ice surface roughness variations in climate simulations in order to correctly represent the implications of sea ice loss under global warming.

Plano de carreira versus crescimento do indivíduo e eficácia das organizações - o caso Instituto Batista de Educação de Vitória (ES)

A temática aqui proposta tem por objetivo analisar até que ponto a implementação de um plano de carreira pode vir a ser um fator de crescimento do indivíduo e de maior eficácia no Instituto Batista de Educação de Vitória (ffiEV). Assim, no presente Estudo de Caso foram realizadas pesquisas bibliográficas e pesquisa de campo mediante aplicação de questionário (entrevistas focalizadas, semi-estruturadas) de forma a embasar conceitualmente a temática e com informações relevantes caracterizar a Instituição, para estabelecer a relação entre plano de carreira, plano de vida e a utilização do capital humano como um fator de crescimento do indivíduo e de maior eficácia organizacional. Os elementos que compõem o quadro de recursos humanos do ffiEV serão apresentados e interpretados sob um enfoque dialético compatível com as proposições de plano de carreira e plano de vida, dos autores elencados na bibliografia No transcorrer dessa dissertação serão contracenados os conceitos de plano de carreira e plano de vida que por um longo período de tempo e talvez ainda hoje, são pensados como não correlacionados. Isto acontece porque, para conseguirmos correlacionar estes conceitos e sistemas, necessitamos aprender a analisá-los de uma perspectiva macro. Neste ponto, pode-se juntar estes conceitos e entender as suas correlações. É claro que estes relacionamentos são complexos, o que é uma das razões pelas quais eles não são enxergados. Olhando para este quadro geral através do conceito plano de carreira/plano de vida, é fácil concluir que o ffiEV é um sistema complexo com subsistemas ativos (humano e técnico) e uma estrutura geral (estrutura). Esta estrutura irá prover meios com os quais os subsistemas irão interagir, e conseqüentemente prover diferentes possibilidades de interação. As interações entre os atores do sistema terão conseqüências que poderão ser medidas através de investigações quantitativas e qualitativas. Estas conseqüências são, por exemplo, qualidade, eficiência organizacional, lucro, satisfação com o trabalho, comprometimento com a organização, ou pode-se dizer de maneira mais geral que estas conseqüências são referentes à saúde do indivíduo e à saúde da organização. Este sistema complexo chamado ffiEV existe e interage em um sistema maior, chamado mercado, que por sua vez é parte de outro sistema, que é a sociedade. O ser humano é também um componente destes dois outros sistemas. Este, então, age e interage em ambientes distintos e correlacionados, que são a instituição (como funcionário), o mercado (como consumidor) e a sociedade (como membro). Por se constatar que o sistema humano em questão interage uma certa quantidade de horas exclusivamente ou quase exclusivamente com a instituição, e uma mesma ou maior quantidade de horas com a sociedade, então não podem ser excluídas realidades da vida de alguém, do seu trabalho na organização ou do seu convívio com família e amigos.

Efeitos organizacionais da implantação de metas e remuneração variável por desempenho: o caso da segurança pública em Minas Gerais

Quais os efeitos práticos que a cobrança de metas provoca nas instituições e nos servidores públicos? E quando se vincula premiações financeiras a elas, qual o resultado? O Brasil vive uma onda recente de implantação de modelos de remuneração variável por desempenho no setor público. Minas Gerais universalizou o sistema em 2008, implantando o Acordo de Resultados e o Prêmio por Produtividade, já tendo gasto 1,3 bilhão de reais com o programa. Mas o otimismo dos gestores não encontra fundamento na teoria. A literatura mostra que sistemas de remuneração variável no setor público fracassam ou têm sucesso muito limitado (OCDE, 2005; Perry, Engbergs e Jun, 2009; Bowman, 2010; Weibel, Rost e Osterloh 2010). Conflitos, dificuldade de mensuração do desempenho, fraude e incapacidade de motivar servidores públicos têm direcionado experiências de incentivo ao fracasso. Alguns poucos estudos mostram que, sob certas condições, a remuneração variável por desempenho pode gerar resultados positivos (Marsden, 2010). Seria o sistema mineiro capaz de superar o pessimismo dos especialistas e alcançar resultados positivos? Quais mecanismos de fato operam quando se implementa metas e remuneração variável em instituições públicas? Este trabalho busca responder estas questões a partir do estudo de caso de três organizações da segurança pública em Minas Gerais: Polícia Militar, Polícia Civil e Corpo de Bombeiros Militar. Foram feitas 46 entrevistas com policiais, bombeiros e com a cúpula das instituições, analisados dados estatísticos – que avaliam a evolução do desempenho, observação participante e monitoramento da percepção da mídia sobre tais efeitos. O resultado mostra que metas e incentivos financeiros geraram profundas mudanças nas instituições pesquisadas. Na Polícia Civil houve crescimento da produtividade, aumento do controle e melhoria de processos internos. Entretanto, o foco na produção quantitativa de inquéritos gerou incentivos para a redução de sua qualidade. Na Polícia Militar observou-se impacto menor, uma vez que esta já havia auferido no passado recente ganhos que o uso de indicadores e metas poderia proporcionar. Ainda assim, observou-se aumento da cobrança interna de resultados. Esse fato foi um dos fatores que contribuiu para um efeito negativo importante: a reclassificação de crimes. Uma estrutura de incentivos e a ausência de obstáculos levaram alguns policiais a reclassificar crimes que tinham natureza próxima para melhorar as estatísticas de suas unidades. No Corpo de Bombeiros o impacto foi altamente positivo, levando a instituição a conceber novas estratégias, gerando ganhos importantes de produtividade e melhoria de resultados para o cidadão. O resultado mostra que metas e incentivos financeiros são muito poderosos e podem gerar resultados positivos ou negativos, dependendo da forma como são implementados. As evidências contradizem, em parte, o pessimismo dos acadêmicos e descortinam o funcionamento dos mecanismos que fazem metas e remuneração variável interferirem no resultado de organizações públicas.

Os efeitos das reclamações online na lealdade dos consumidores: um estudo experimental

In an environment of constant change, technological developments, market competition and more informed consumers, the search for a lasting relationship through the conquest of loyalty has become the objective of companies. However, several authors suggest that this loyalty can be affected by negative comments available on the internet. Therefore, this dissertation has as objective to examine if the complaints are available on the internet impact the loyalty to a brand of mobile phone. The research used as the basis the Expanded NCSB model suggest by Johnson et al. (2001), studying five prominent drives of loyalty: image/brand reputation, affective commitment, calculative commitment, perceived value and trust, beyond the satisfaction construct as moderator variable. The research method adopted was the experimental design which included 285 undergraduate students, with the trial which included 285 undergraduate students, with the field study of the mobile industry, specifically, the brands of cell phones. The research approach was quantitative and methods were descriptive statistics, factor analysis, cluster analysis, linear regression and non-parametric test of Wilcoxon for data analysis. Of the 16 hypothesis stemmed from the research model proposed, 12 were confirmed. The results showed that the complaint available on the internet, here represented by the available on the site Reclame Aqui, may impact consumer perceptions about brand loyalty, as well as its antecedents, being that these complaints can affect all the consumers, regardless of historical satisfaction with the brand. It also noted the positive relationship between the independent variables trust, image/brand reputation, perceived value, affective commitment and calculative commitment and the dependent variable - loyalty, even when considering the data obtained after exposure to the complaint. However, no unanimous conclusion that the relationship between these variables was strongest in the group with satisfactory experience. At the first moment of the research, the trust was the most important variable for the formation of loyalty. However, after exposure to treatment, the image/brand reputation, was more relevant. Contributions of the study, limitations and recommendations for future researches are approached in the present investigation

Fatores de satisfação de empregados: um estudo com docentes de instituição de educação tecnológica

This Master of Science Thesis deals with investigating the factors affecting employees satisfaction studying the case of teachers on a technological education institution. It is surveyed teachers in a sample of size 42 out of 316. It is used a form that deploys a model of satisfaction antecedents factors comprised of work system, professional development, teaching activity, physical environment, pay, and problems management. The sample was found representative (χ2 test) based on genre, tenure, degrees, and age. The model for satisfaction with the institution presented a adjusted r2 > 0,80 and the main factors affecting it was found to be work system, professional development, and teaching activity. For the satisfaction with the career, the model results with a r2 > 0,70 and as main factors professional development, teaching activitiy and pay. The variables contribuition for the students education and use of suggestions were ones of the main variables appearing in the models. The results suggest an improvement in the model regarding the previous models used by Silva (2003) and Cruz Filho (2007) regarding model explicability of teacher satisfaction