Differences between theoretical predictions and operational performance in a stock control application

Over the past decade, several experienced Operational Researchers have advanced the view that the theoretical aspects of model building have raced ahead of the ability of people to use them. Consequently, the impact of Operational Research on commercial organisations and the public sector is limited, and many systems fail to achieve their anticipated benefits in full. The primary objective of this study is to examine a complex interactive Stock Control system, and identify the reasons for the differences between the theoretical expectations and the operational performance. The methodology used is to hypothesise all the possible factors which could cause a divergence between theory and practice, and to evaluate numerically the effect each of these factors has on two main control indices - Service Level and Average Stock Value. Both analytical and empirical methods are used, and simulation is employed extensively. The factors are divided into two main categories for analysis - theoretical imperfections in the model, and the usage of the system by Buyers. No evidence could be found in the literature of any previous attempts to place the differences between theory and practice in a system in quantitative perspective nor, more specifically, to study the effects of Buyer/computer interaction in a Stock Control system. The study reveals that, in general, the human factors influencing performance are of a much higher order of magnitude than the theoretical factors, thus providing objective evidence to support the original premise. The most important finding is that, by judicious intervention into an automatic stock control algorithm, it is possible for Buyers to produce results which not only attain but surpass the algorithmic predictions. However, the complexity and behavioural recalcitrance of these systems are such that an innately numerate, enquiring type of Buyer needs to be inducted to realise the performance potential of the overall man/computer system.

Fast and accurate hand pose detection for human-robot interaction

[EN]Enabling natural human-robot interaction using computer vision based applications requires fast and accurate hand detection. However, previous works in this field assume different constraints, like a limitation in the number of detected gestures, because hands are highly complex objects difficult to locate. This paper presents an approach which integrates temporal coherence cues and hand detection based on wrists using a cascade classifier. With this approach, we introduce three main contributions: (1) a transparent initialization mechanism without user participation for segmenting hands independently of their gesture, (2) a larger number of detected gestures as well as a faster training phase than previous cascade classifier based methods and (3) near real-time performance for hand pose detection in video streams.

Cognitive style factors affecting database query performance

As end-user computing becomes more pervasive, an organization's success increasingly depends on the ability of end-users, usually in managerial positions, to extract appropriate data from both internal and external sources. Many of these data sources include or are derived from the organization's accounting information systems. Managerial end-users with different personal characteristics and approaches are likely to compose queries of differing levels of accuracy when searching the data contained within these accounting information systems. This research investigates how cognitive style elements of personality influence managerial end-user performance in database querying tasks. A laboratory experiment was conducted in which participants generated queries to retrieve information from an accounting information system to satisfy typical information requirements. The experiment investigated the influence of personality on the accuracy of queries of varying degrees of complexity. Relying on the Myers–Briggs personality instrument, results show that perceiving individuals (as opposed to judging individuals) who rely on intuition (as opposed to sensing) composed queries more accurately. As expected, query complexity and academic performance also explain the success of data extraction tasks.

Avaliação da Usabilidade de um Projeto de eHealth, enquadrado na visão europeia de Health Technology Assessment (HTA)

Trabalho de projeto apresentado à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Audiovisual e Multimédia.

Interfície de control de dades en una fàbrica

Aquest treball tracta de l'estudi i creació de la interfície d'una aplicació que reculli les dades de control generades en un procés productiu real en una petita planta de fabricació amb cinc treballadors.

Estudi dels portals web de consulta bibliogràfica mèdica i disseny d'un prototip

L'estudi tracta d'establir les bases per al disseny d'un lloc web de consulta bibliogràfica mèdica des del punt de vista de la Interacció Humana amb l'Ordinador (IHO) tenint en compte els principis del Disseny Centrat en l'Usuari (DCU). En una primera part, l'estudi analitza un conjunt de portals ja existents d'aquesta temàtica i d'ús freqüent entre els professionals sanitaris. En una segona part, es proposa un prototip de portal web amb idees noves que millorin i proporcionin un valor afegit a les ja existents.

Anàlisi de la usabilitat web del Departament d'Ensenyament de la Generalitat de Catalunya

En el present treball farem un anàlisis complet de la usabilitat del lloc web del Departament d'Ensenyament de la Generalitat de Catalunya, tant des de el punt de vista heurístic com de l'ús en entorn real. Identificarem els punts forts i dèbils i, finalment, farem una proposta breu de millora i treball futur. Volem d'aquesta manera millorar l'experiència del ciutadà amb la institució i la qualitat de la seva relació.

Monitoramento de hosts em redes tcp/ip sobre base georreferenciada com métricas de qualidade

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)