This study presents two computer vision based algorithms for automated 2D detection of construction workers and equipment from site video streams. The state-of-the-art research proposes semi-automated detection methods for tracking of construction workers and equipment. Considering the number of active equipment and workers on jobsites and their frequency of appearance in a camera's field of view, application of semi-automated techniques can be time-consuming. To address this limitation, two new algorithms based on Histograms of Oriented Gradients and Colors (HOG+C), 1) HOG+C sliding detection window technique, and 2) HOG+C deformable part-based model are proposed and their performance are compared to the state-of-the-art algorithm in computer vision community. Furthermore, a new comprehensive benchmark dataset containing over 8,000 annotated video frames including equipment and workers from different construction projects is introduced. This dataset contains a large range of pose, scale, background, illumination, and occlusion variation. The preliminary results with average performance accuracies of 100%, 92.02%, and 89.69% for workers, excavators, and dump trucks respectively, indicate the applicability of the proposed methods for automated activity analysis of workers and equipment from single video cameras. Unlike other state-of-the-art algorithms in automated resource tracking, these methods particularly detects idle resources and does not need manual or semi-automated initialization of the resource locations in 2D video frames. / Master of Science

Objectives: To determine if force differences exist between isometric pulling positions corresponding to key positions of the deadlift. Design: Cross-sectional evaluation of isometric strength Methods: 14 powerlifters performed isometric pulls on a force plate at 3 key positions related to the deadlift (at the floor, just above the patella, and 5-6 cm short of lockout) and in the mid thigh pull position (MTP). A 1x4 repeated measures ANOVA was used to ascertain differences between the various pulling positions tested. Bonferroni-adjusted paired samples t-tests were used post-hoc. Results: Forces generated at each bar height were significantly different (F(3,39) = 51.058, p2=0.80). Paired samples t-tests showed significant differences between positions, revealing a trend of greater force generation at increasing heights for positions corresponding to the deadlift. Force generated in the mid thigh pull position was significantly higher than any other position. Conclusion: In positions corresponding to the deadlift, force generation increases at higher bar heights.

Thesis (Ph.D. (Industrial Psychology) )--North-West University, Potchefstroom Campus, 2007.

We propose a mathematical framework that integrates low-level sensory signals from monitoring engineering systems and their components with high-level decision models for maintenance optimization. Our objective is to derive optimal adaptive maintenance strategies that capitalize on condition monitoring information to update maintenance actions based upon the current state of health of the system. We refer to this sensor-based decision methodology as "sense-and-respond logistics". As a first step, we develop and extend degradation models to compute and periodically update the remaining life distribution of fielded components using in situ degradation signals. Next, we integrate these sensory updated remaining life distributions with maintenance decision models to; (1) determine, in real-time, the optimal time to replace a component such that the lost opportunity costs due to early replacements are minimized and system utilization is increased, and (2) sequentially determine the optimal time to order a spare part such that inventory holding costs are minimized while preventing stock outs. Lastly, we integrate the proposed degradation model with Markov process models to derive structured replacement and spare parts ordering policies. In particular, we show that the optimal maintenance policy for our problem setting is a monotonically non-decreasing control limit type policy. We validate our methodology using real-world data from monitoring a piece of rotating machinery using vibration accelerometers. We also demonstrate that the proposed sense-and-respond decision methodology results in better decisions and reduced costs compared to other traditional approaches.

Internationally, as well as locally, the trend is for companies to use call centres as their preferred method of service delivery. The increase in the use of call centres as a service delivery mechanism thus provides many more employment opportunities. Within call centres, service is primarily delivered by frontline employees referred to as customer service representatives (CSRs). While nothing seems to stop the growth of call centres and the increase of employment opportunities within them, working in call centres is not necessarily experienced as pleasant. Working in a call centre is frequently seen as stressful and the work in such a centre can foster burnout. Burnout is considered to be a pathogenic construct. The first purpose of this study was to describe and investigate the contribution of six central characteristics (antecedents) of call centre work environments and their influence on burnout, affective commitment and turnover intentions. These characteristics were work overload; electronic performance monitoring; lack of career and promotion opportunities, lack of skill variety and emotional labour. An incidental sample of customer service representatives (N=146) was obtained from the inbound service call centre of a large financial company. AU six independent variables were found to be significantly related to the experience of burnout, affective commitment and turnover intentions. Multiple regression analysis made it possible to establish that work overload, lack of career and promotion opportunities and skill variety, and emotional labour were the most important predictors of burnout, whereas lack of career and promotion opportunities was the most significant predictors of both affective commitment and turnover intentions. Burnout had a direct effect on turnover intentions and was not mediated by affective commitment. One antecedent that is often associated with the development of burnout is daily hassles, but daily hassles as an antecedent of burnout in call centres has not been studied before. The second purpose of this study was to develop a short Call Centre Daily Hassle Diagnostic Questionnaire that could be used to identify the most common daily hassles that call centre agents experience in their working lives, both within the work environment and within their day-to-day personal lives, and to determine the relationship between it and burnout. A cross-sectional survey research design was used with an accidental sample (N=394) taken from a service and sales call centre. An exploratory factor analysis of the data resulted in a six-factor model of daily hassles within call centres that significantly predicted exhaustion. The factors were daily demands, continuous change, co-worker hassles, demotivating work environment, transportation hassles and inner concerns. In the third part of this research thesis there is a shift away from the pathogenic paradigm towards a more salutogenic/fortigenic paradigm. Very little previous research has been done on adult resilience. The purpose of the third study was to explore the concept of adult resilience and to identify and describe the protective and vulnerability factors that play a role in adult resilience. Through the use of an exploratory factor analysis, eight factors were identified that played a role in adult resilience. They were Confidence and Optimism, Positive Reinterpretation, Facing Adversity, Support, Determination, Negative Rumination, Religion and Helplessness. Based on the findings of this research, some practical recommendations were made for the management of call centres to reduce the development of burnout and turnover intentions, on how to utilise the Hassle-based Diagnostic Scale and on how to apply the Adult Resilience Indicator in the training and development of resilience. / Thesis (Ph.D. (Industrial Psychology) )--North-West University, Potchefstroom Campus, 2007.

Patient wait times and care service times are key performance measures for care processes in hospitals. Managing the quality of care delivered by these processes in real-time is challenging. A key challenge is to correlate source medical events to infer the care process states that define patient wait times and care service times. Commercially available complex event processing engines do not have built in support for the concept of care process state. This makes it unnecessarily complex to define and maintain rules for inferring states from source medical events in a care process. Another challenge is how to present the data in a real-time BI dashboard and the underlying data model to use to support this BI dashboard. Data representation architecture can potentially lead to delays in processing and presenting the data in the BI dashboard. In this research, we have investigated the problem of real-time monitoring of care processes, performed a gap analysis of current information system support for it, researched and assessed available technologies, and shown how to most effectively leverage event driven and BI architectures when building information support for real-time monitoring of care processes. We introduce a state monitoring engine for inferring and managing states based on an application model for care process monitoring. A BI architecture is also leveraged for the data model to support the real-time data processing and reporting requirements of the application’s portal. The research is validated with a case study to create a real-time care process monitoring application for an Acute Coronary Syndrome (ACS) clinical pathway in collaboration with IBM and Osler hospital. The research methodology is based on design-oriented research.

Internationally, as well as locally, the trend is for companies to use call centres as their preferred method of service delivery. The increase in the use of call centres as a service delivery mechanism thus provides many more employment opportunities. Within call centres, service is primarily delivered by frontline employees referred to as customer service representatives (CSRs). While nothing seems to stop the growth of call centres and the increase of employment opportunities within them, working in call centres is not necessarily experienced as pleasant. Working in a call centre is frequently seen as stressful and the work in such a centre can foster burnout. Burnout is considered to be a pathogenic construct. The first purpose of this study was to describe and investigate the contribution of six central characteristics (antecedents) of call centre work environments and their influence on burnout, affective commitment and turnover intentions. These characteristics were work overload; electronic performance monitoring; lack of career and promotion opportunities, lack of skill variety and emotional labour. An incidental sample of customer service representatives (N=146) was obtained from the inbound service call centre of a large financial company. AU six independent variables were found to be significantly related to the experience of burnout, affective commitment and turnover intentions. Multiple regression analysis made it possible to establish that work overload, lack of career and promotion opportunities and skill variety, and emotional labour were the most important predictors of burnout, whereas lack of career and promotion opportunities was the most significant predictors of both affective commitment and turnover intentions. Burnout had a direct effect on turnover intentions and was not mediated by affective commitment. One antecedent that is often associated with the development of burnout is daily hassles, but daily hassles as an antecedent of burnout in call centres has not been studied before. The second purpose of this study was to develop a short Call Centre Daily Hassle Diagnostic Questionnaire that could be used to identify the most common daily hassles that call centre agents experience in their working lives, both within the work environment and within their day-to-day personal lives, and to determine the relationship between it and burnout. A cross-sectional survey research design was used with an accidental sample (N=394) taken from a service and sales call centre. An exploratory factor analysis of the data resulted in a six-factor model of daily hassles within call centres that significantly predicted exhaustion. The factors were daily demands, continuous change, co-worker hassles, demotivating work environment, transportation hassles and inner concerns. In the third part of this research thesis there is a shift away from the pathogenic paradigm towards a more salutogenic/fortigenic paradigm. Very little previous research has been done on adult resilience. The purpose of the third study was to explore the concept of adult resilience and to identify and describe the protective and vulnerability factors that play a role in adult resilience. Through the use of an exploratory factor analysis, eight factors were identified that played a role in adult resilience. They were Confidence and Optimism, Positive Reinterpretation, Facing Adversity, Support, Determination, Negative Rumination, Religion and Helplessness. Based on the findings of this research, some practical recommendations were made for the management of call centres to reduce the development of burnout and turnover intentions, on how to utilise the Hassle-based Diagnostic Scale and on how to apply the Adult Resilience Indicator in the training and development of resilience. / Thesis (Ph.D. (Industrial Psychology) )--North-West University, Potchefstroom Campus, 2007.

Avec l'explosion du volume de données produites chaque année, les applications du domaine du traitement de graphes ont de plus en plus besoin d'être parallélisées et déployées sur des architectures distribuées afin d'adresser le besoin en mémoire et en ressource de calcul. Si de telles architectures larges échelles existent, issue notamment du domaine du calcul haute performance (HPC), la complexité de programmation et de déploiement d’algorithmes de traitement de graphes sur de telles cibles est souvent un frein à leur utilisation. De plus, la difficile compréhension, a priori, du comportement en performances de ce type d'applications complexifie également l'évaluation du niveau d'adéquation des architectures matérielles avec de tels algorithmes. Dans ce contexte, ces travaux de thèses portent sur l’exploration d’algorithmes de traitement de graphes sur architectures distribuées en utilisant GraphLab, un Framework de l’état de l’art dédié à la programmation parallèle de tels algorithmes. En particulier, deux cas d'applications réelles ont été étudiées en détails et déployées sur différentes architectures à mémoire distribuée, l’un venant de l’analyse de trace d’exécution et l’autre du domaine du traitement de données génomiques. Ces études ont permis de mettre en évidence l’existence de régimes de fonctionnement permettant d'identifier des points de fonctionnements pertinents dans lesquels on souhaitera placer un système pour maximiser son efficacité. Dans un deuxième temps, une étude a permis de comparer l'efficacité d'architectures généralistes (type commodity cluster) et d'architectures plus spécialisées (type serveur de calcul hautes performances) pour le traitement de graphes distribué. Cette étude a démontré que les architectures composées de grappes de machines de type workstation, moins onéreuses et plus simples, permettaient d'obtenir des performances plus élevées. Cet écart est d'avantage accentué quand les performances sont pondérées par les coûts d'achats et opérationnels. L'étude du comportement en performance de ces architectures a également permis de proposer in fine des règles de dimensionnement et de conception des architectures distribuées, dans ce contexte. En particulier, nous montrons comment l’étude des performances fait apparaitre les axes d’amélioration du matériel et comment il est possible de dimensionner un cluster pour traiter efficacement une instance donnée. Finalement, des propositions matérielles pour la conception de serveurs de calculs plus performants pour le traitement de graphes sont formulées. Premièrement, un mécanisme est proposé afin de tempérer la baisse significative de performance observée quand le cluster opère dans un point de fonctionnement où la mémoire vive est saturée. Enfin, les deux applications développées ont été évaluées sur une architecture à base de processeurs basse-consommation afin d'étudier la pertinence de telles architectures pour le traitement de graphes. Les performances mesurés en utilisant de telles plateformes sont encourageantes et montrent en particulier que la diminution des performances brutes par rapport aux architectures existantes est compensée par une efficacité énergétique bien supérieure. / With the advent of ever-increasing graph datasets in a large number of domains, parallel graph-processing applications deployed on distributed architectures are more and more needed to cope with the growing demand for memory and compute resources. Though large-scale distributed architectures are available, notably in the High-Performance Computing (HPC) domain, the programming and deployment complexity of such graphprocessing algorithms, whose parallelization and complexity are highly data-dependent, hamper usability. Moreover, the difficult evaluation of performance behaviors of these applications complexifies the assessment of the relevance of the used architecture. With this in mind, this thesis work deals with the exploration of graph-processing algorithms on distributed architectures, notably using GraphLab, a state of the art graphprocessing framework. Two use-cases are considered. For each, a parallel implementation is proposed and deployed on several distributed architectures of varying scales. This study highlights operating ranges, which can eventually be leveraged to appropriately select a relevant operating point with respect to the datasets processed and used cluster nodes. Further study enables a performance comparison of commodity cluster architectures and higher-end compute servers using the two use-cases previously developed. This study highlights the particular relevance of using clustered commodity workstations, which are considerably cheaper and simpler with respect to node architecture, over higher-end systems in this applicative context. Then, this thesis work explores how performance studies are helpful in cluster design for graph-processing. In particular, studying throughput performances of a graph-processing system gives fruitful insights for further node architecture improvements. Moreover, this work shows that a more in-depth performance analysis can lead to guidelines for the appropriate sizing of a cluster for a given workload, paving the way toward resource allocation for graph-processing. Finally, hardware improvements for next generations of graph-processing servers areproposed and evaluated. A flash-based victim-swap mechanism is proposed for the mitigation of unwanted overloaded operations. Then, the relevance of ARM-based microservers for graph-processing is investigated with a port of GraphLab on a NVIDIA TX2-based architecture.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Business Administration in the Faculty of Business at the Cape Peninsula University of Technology 2014 / Call centres have become an important source for organisations to provide efficient information to their customers through cost-effective communication channels. Call centres are defined as a work environment in which the main business is mediated by computer- and telephone-based technologies that allow the effective distribution of incoming calls to available staff, and permit customer–employee communication simultaneously with the use of display screen equipment (DSE) and instant access to information. Working in a call centre is often linked with high stress levels, difficult customers, shift work, high workload demand, absenteeism and high employee turnover rates. The work characteristics of call centres include performance targets where employees are required to achieve set targets, undergo close performance monitoring, performance appraisal systems, limited task variation, repetitive work and limited autonomy. The physical environment in the call centre is often associated with open-plan office layouts and booths where noise levels and workstations are positioned in close proximity to each other. Wellbeing in call centres has become a concern and the research was undertaken to establish what effects the working environment (physical environment and job characteristics) in call centres in the Cape Metropole has on the wellbeing of call centre agents. A quantitative research method was employed in the study. A structured questionnaire was distributed via SurveyMonkey® to call centre agents from four participating call centres in the Cape Metropole. The combined target population of the four call centres was 760. A sample size of 200 was determined by using the Raosoft Incorporated® calculation tool. Although the aforesaid sample size sufficed, a response rate of 275 was received. Questions relating to job characteristics and significance of the work were based on the Job Diagnostic Survey by Hackman and Oldham. Social support questions were based on the instrument developed by Caplan, Cobb, French, Van Harrison & Pinneau in 1975. Job demand questions were based on the instrument developed by Karasek in 1979, and only the section on job demand was used. Performance monitoring and physical work environment were measured by using the questions based on these variables by Sprigg et al in 2003. Emotional wellbeing questions relating to burnout were measured using the Oldenburg Burnout Inventory. The wellbeing questions relating to vocal health, optical health and auditory health were based on the questionnaires developed by Sprigg et al. in 2003. General health was measured using the “Somatic Complaints” section of the NIOSH Generic Job Stress Questionnaire. Musculoskeletal health problems were measured using the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) developed by Hedge in 1994. Research question 1 addressed the gender perceptions of job characteristics, physical work environment and emotional and physical wellbeing. A T-test was conducted to answer the research question and the results revealed that there was no significant difference in gender perception on job characteristics; however there was a significant difference in perception of the physical work environment and wellbeing. Research question 2 addressed whether there is a significant difference in emotional and physical wellbeing experienced by call centre agents from various industries. A MANOVA analysis was conducted to determine the significance in industries, p = .015, and an ANOVA analysis was conducted that revealed agents working in the online retail as well as financial service industries were more likely to experience disengagement, p = .035. Research question 3 addressed the factors in the workplace environment that contribute to emotional and physical wellbeing problems. An ANOVA analysis was conducted and the results revealed lack of skills variety, p = .014, contributes to exhaustion; lack of autonomy, p = .040, contributes to disengagement; lack of supervisor support, p = .009, contributes to exhaustion, job demands, p = .000, contribute to exhaustion, performance monitoring, p = .036, contributes to exhaustion; and workstation layout, p = .001, contributes to auditory health problems. Research question 4 addressed whether there is a significant relationship between job characteristics, physical work environment and wellbeing. A Pearson correlation analysis was conducted and the results revealed that there is a significant relationship between job characteristics, physical work environment, and wellbeing. It can be concluded that the workplace environment does have an impact on the wellbeing of call centre agents in the Cape Metropole. It is imperative that the management of call centres understand the nature of the job and how the physical environment contributes to job stress; burnout; vocal, auditory, and optical health problems; and musculoskeletal disorders. The researcher recognises that there are essential job characteristics associated with call centre work but that there are elements of the job that can be redesigned to improve the wellbeing of call centre agents. It is recommended that management implement interventions which will redesign those elements within the workplace environment that contribute to wellbeing issues. The findings of this study add to existing literature and knowledge of the workplace environment and wellbeing of call centre agents.

In this thesis we proposed and tested a new method for creating synthetic workloads. Our method takes the dynamic behaviour into consideration, whereas previous studies only consider the static behaviour. This was done by recording performance monitor counters (PMC) events from a reference application. These events were then used to calculate the hardware load characteristics, in our case cache miss ratios, that were stored for each sample and used as input to a load regulator. A signalling application was then used together with a load regulator and a cache miss generator to tune the hardware characteristics until they were similar to those of the reference application. For each sample, the final parameters from the load regulator were stored in order to be able to simulate it. By simulating all samples with the same sampling period with which they were recorded, the dynamic behaviour of the reference application could be simulated. Measurements show that this was successful for L1 D$ miss ratio, but not for L1 I$ miss ratio and only to a small extent for L2 D$ miss ratio. We were also able to show that the total convergence time for the regulator could be reduced by using case-based reasoning to select the initial parameters from similar samples.