The Distributed Coordination Function (DCF) is the oldest and most widely-used IEEE 802.11 contention-based channel access control protocol. DCF adds a significant amount of overhead in the form of preambles, frame headers, randomised binary exponential back-off and inter-frame spaces. Having accurate and verified performance models for DCF is thus integral to understanding the performance of IEEE 802.11 as a whole. In this document DCF performance is measured subject to two different workload models using an IEEE 802.11g test bed. Bianchi proposed the first accurate analytic model for measuring the performance of DCF. The model calculates normalised aggregate throughput as a function of the number of stations contending for channel access. The model also makes a number of assumptions about the system, including saturation conditions (all stations have a fixed-length packet to send at all times), full-connectivity between stations, constant collision probability and perfect channel conditions. Many authors have extended Bianchi's machine model to correct certain inconsistencies with the standard, while very few have considered alternative workload models. Owing to the complexities associated with prototyping, most models are verified against simulations and not experimentally using a test bed. In addition to a saturation model we considered a more realistic workload model representing wireless Internet traffic. Producing a stochastic model for such a workload was a challenging task, as usage patterns change significantly between users and over time. We implemented and compared two Markov Arrival Processes (MAPs) for packet arrivals at each client - a Discrete-time Batch Markovian Arrival Process (D-BMAP) and a modified Hierarchical Markov Modulated Poisson Process (H-MMPP). Both models had parameters drawn from the same wireless trace data. It was found that, while the latter model exhibits better Long Range Dependency at the network level, the former represented traces more accurately at the client-level, which made it more appropriate for the test bed experiments. A nine station IEEE 802.11 test bed was constructed to measure the real world performance of the DCF protocol experimentally. The stations used IEEE 802.11g cards based on the Atheros AR5212 chipset and ran a custom Linux distribution. The test bed was moved to a remote location where there was no measured risk of interference from neighbouring radio transmitters in the same band. The DCF machine model was fixed and normalised aggregate throughput was measured for one through to eight contending stations, subject to (i) saturation with fixed packet length equal to 1000 bytes, and (ii) the D-BMAP workload model for wireless Internet traffic. Control messages were forwarded on a separate wired backbone network so that they did not interfere with the experiments. Analytic solver software was written to calculate numerical solutions for thee popular analytic models for DCF and compared the solutions to the saturation test bed experiments. Although the normalised aggregate throughput trends were the same, it was found that as the number of contending stations increases, so the measured aggregate DCF performance diverged from all three analytic model's predictions; for every station added to the network normalised aggregate throughput was measured lower than analytically predicted. We conclude that some property of the test bed was not captured by the simulation software used to verify the analytic models. The D-BMAP experiments yielded a significantly lower normalised aggregate throughput than the saturation experiments, which is a clear result of channel underutilisation. Although this is a simple result, it highlights the importance of the traffic model on network performance. Normalised aggregate throughput appeared to scale more linearly when compared to the RTS/CTS access mechanism, but no firm conclusion could be drawn at 95% confidence. We conclude further that, although normalised aggregate throughput is appropriate for describing overall channel utilisation in the steady state, jitter, response time and error rate are more important performance metrics in the case of bursty traffic.

This dissertation consists of two essays. The first essay draws on psychology theories to propose a framework for incorporating personality variables into the study of performance control systems. The second essay reports an experiment to highlight the implications of one component of this framework: the efficacy of exogenously assigned performance control systems can depend on the personality types of employees who are subject to these systems. / text

The main purpose of this report is to identify and describe the type of behaviors that should be promoted in a matrix organization. This report shows how the performance management system is a very important tool in promoting these behaviors. The report starts with an introduction to the relationship between the success of a matrix structure and the appropriate performance management system followed by the definition of important concepts in this topic. Next, the report provides general recommendations to the leaders of matrix organizations with respect their performance management system. Finally, a case study of a company with this type of structure is analyzed. / text

The purpose of this study was to determine a model to integrate managerial and non-managerial expectations, regarding performance appraisals, in an organisation-specific performance appraisal system’s design. The sample consisted of 178 respondents that completed a newly developed questionnaire, aimed at obtaining the respondents input in the performance appraisal system’s design. The results of the managerial group were compared to the non-managerial group. Some significant differences were obtained regarding the design of the performance appraisal system. The results and implications are discussed. / Dissertation (MCom)--University of Pretoria, 2009. / Human Resource Management / unrestricted

In the last three decades, a growing body of research has suggested that using a mix or system of human resources management (HRM) practices can lead to superior organizational performance. These practices (such as selective recruitment and hiring procedures, performance-based compensation systems, employee participation, and training and development) have been referred to as high performance work systems (HPWS) and originated from the study of strategic human resource management (SHRM), where researchers have examined the impact of these systems on organizational performance outcomes. The relationship between HRM and organizational performance has received increasing interest from scholars and practitioners in the field of public administration. Scholars strive to identify the effects of HRM practices on organizational performance based on the notion that these practices will lead to enhanced attitudinal outcomes, such as organizational commitment, job satisfaction, and motivation, which will have positive impacts on organizational performance. This study contributes to further our understanding of the impact of management on performance in public organizations through empirical evidence drawn from theories of HRM. The growing interest among scholars in understanding the effects of management on performance presumes that the adoption of best practices will lead to improvements in organizational performance. The purpose of this mixed-methods study is to examine the effects of HPWS practices on individual worker attitudes in international governmental organizations (IGOs) by reporting the results of a staff survey and follow-up interviews conducted on a cross-section of the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) employees. The UNRWA is an international relief and human development Agency with a quasi-governmental role, delivering essential public services to over five million registered Palestinian refugees. UNRWA services include education, healthcare, social services, and emergency aid. In 2006, the UNRWA began a comprehensive reform program to strengthen its management capacity. Accordingly, one of the main achievements of the reform process is the deployment of new HRM systems that included recruitment strategies, performance appraisals, training and development, and compensation and rewards systems. The underlying message of the reform process has been adopting HPWS practices, which is the object of this study. Since the 1990s, the UNRWA has become increasingly interested in policy analysis and organizational research. Especially because of recent changes in the Agency’s management style, the UNRWA has become more focused on integrating knowledge and management research into its work. Therefore, when the researcher sought permission to examine the effects of the newly adopted HPWS practices on employee attitudes, the staff and upper management were very collaborative and co-operative. Surveys and interviews were conducted with program administrators, operations directors, and field staff, representing employees from different countries with varying lengths of service as well as an extensive range of levels of education and professional backgrounds. A total of 505 questionnaires were distributed in seven service departments and a total of 234 usable responses were obtained. In addition to questionnaires, a total of 10 face-to-face interviews were conducted to explore the data obtained from questionnaires and to understand further the implications of applying HPWS practices in an IGO context. Statistical analysis of the survey data and interviews provided a representation of the effects of four bundles of HPWS adopted by the organization (independent variables), on four worker attitude measures (dependent variables). The four independent variables are the HPWS practices that are the most common and most accepted in the HRM literature: staffing and recruitment, compensation and rewards, performance appraisal, and training and development. The four dependent variables are employee commitment, job satisfaction, motivation, and intention to quit. Preliminary statistical analysis consisted of descriptive statistics for all study variables, as well as Cronbach’s alpha for measuring the internal consistency reliability coefficients for all the survey subscales to examine its internal consistency. Four research hypotheses were tested using multiple regression analyses and Pearson correlation coefficients in an attempt to estimate the net effect of each of the independent variables and understand the relationship between study variables. The bivariate relationships between the dependent and independent variables have shown that the relationships are in the anticipated directions. One of the main conclusions regarding the effects of specific HPWS practices in an IGO context is that some practices, such as training and development, outperform other practices, such as staffing and recruitment. These findings are consistent with previous research on multinational corporations operating in different national contexts, and other studies comparing the effects of HPWS in different industries. The results also indicated that HPWS practices have synergistic and complementary effects on each of the employee attitudes that exceed their individual effects. Therefore, in order to expand our understanding of the effects of HPWS on organizational performance, different variables need to be considered such as national context, industry, and other organizational factors may moderate the HRM–performance relationship. The findings of this study support previous studies in this stream of research. The qualitative data were used to verify quantitative data and provide insights that were difficult to gain from surveys alone. The qualitative data indicated that more effective implementation and administration of HPWS practices would lead to better employee outcomes. In other words, the newly announced austerity measures negatively influence perceptions towards the newly implemented HPWS, which may also have influenced employee attitude outcomes.

No

XXX Pharmacy is an independently-owned retail pharmacy in Johannesburg. Good Pharmacy Practice standards make it mandatory for pharmacists to provide “pharmaceutical care”, a highly patient-centred approach to providing pharmaceutical services. Since XXX Pharmacy has a high patient load, a shortage of dispensary staff and a strategic focus on operational efficiency, the question arose whether pharmacists comply fully with Good Pharmacy Practice standards for the provision of pharmaceutical care. Non-compliance poses operational risks that could undermine the business’s financial performance. The research statement was thus that the current performance management system undermines compliance with Good Pharmacy Practice standards for the provision of pharmaceutical care to patients. A triangulation approach was used. The quantitative research method, in which 200 patients completed a questionnaire, investigated two research objectives: (i) whether the pharmacy complies with Good Pharmacy Practice standards for pharmaceutical care; and (ii) whether there is a relationship between patients’ race or gender and their responses. The qualitative research method involved conducting individual semi-structured interviews with all four dispensary employees to achieve another two research objectives: (i) to determine whether the provision of pharmaceutical care is viewed as a key performance area by pharmacists; and (ii) to investigate what aspects of the implementation of the performance management system are viewed as enabling or undermining the provision of pharmaceutical care.

Mini-research report presented in partial fulfillment of the requirements for the degree of Master of Business Administration at the University of Stellenbosch. / ENGLISH ABSTRACT: This research report is focused on the phenomenon that various Key Performance Indicators (KPIs) used by an organisation as part of their Performance Management systems in support of their strategic objectives will sometimes also drive non-productive behaviour. Thus although the intention might be that the KPI should promote a specific strategic objective, the very same KPI might drive additional behaviour that might not be aligned with the strategic objectives at all or could even be downright destructive. The purpose of this research study is to develop an analysis methodology that can be used to identify those KPIs that drive negative secondary behaviour (the intended positive behaviour being the primary behaviour). The methodology must also assist in identifying preventive measures that can be used to mitigate the risk posed by the negative behaviour. An interesting aspect of this research report is that it cross-references between the business and engineering disciplines by means of adapting techniques used in engineering to assist with a business management problem. The result of this research is a KPI Effectiveness Analysis that has gone through a trail phase where a number of case studies were analysed by means of this tool. The results were conclusive and the analysis tool found to be of great assistance. / AFRIKAANSE OPSOMMING: Hierdie navorsingsverslag fokus op die verskynsel dat Sleutel Prestasie Indikators (SPI's)wat deur ondernemings gebruik word as deel van hul prestasiebestuur-stelsels en wat ten doel het om die strategiese doelwitte van die onderneming te ondersteun, soms ook nie-produktiewe gedrag bevorder. Dus alhoewel dit die intensie met die SPI mag wees om gedrag te bevorder wat die strategiese doelwitte sal ondersteun, dieselfde SPI ook gedrag kan bevorder wat glad nie die strategiese doelwitte ondersteun nie en dalk self destruktief van aard kan wees. Die doel van hierdie navorsingstudie is om 'n analise metodologie te ontwikkel wat gebruik kan word om die SPI's te identifiseer wat negatiewe sekondêre gedrag bevorder (waar die bedoelde gedrag as die primêre gedrag gesien word). Die metodologie moet ook die identifisering van moontlike voorkomende stappe help fasiliteer wat gebruik kan word om die risiko van negatiewe gedrag te vernminder. 'n Interessante aspek van hierdie navorsingsverslag is dat daar 'n kruisverwysing gedoen word tussen die besigheids- en ingenieursdissipline deur tegnieke wat in die ingenieursrigting gebruik word aan te pas ten einde te help met 'n besigheidsbestuursprobleem. Die resultaat van die navorsing is 'n SPI Effektiwiteitsanalise wat tydens 'n toetsfase in 'n paar gevallestudies geanaliseer is deur hierdie metode te gebruik. Die resultate was konkreet en bewys dat die analise metode van groot hulp is.

Despite the progress made in developing more advanced compilers for embedded systems, programming of embedded high-performance computing systems based on Digital Signal Processors (DSPs) is still a highly skilled manual task. This is true for single-processor systems, and even more for embedded systems based on multiple DSPs. Compilers often fail to optimise existing DSP codes written in C due to the employed programming style. Parallelisation is hampered by the complex multiple address space memory architecture, which can be found in most commercial multi-DSP configurations. This thesis develops an integrated optimisation and parallelisation strategy that can deal with low-level C codes and produces optimised parallel code for a homogeneous multi-DSP architecture with distributed physical memory and multiple logical address spaces. In a first step, low-level programming idioms are identified and recovered. This enables the application of high-level code and data transformations well-known in the field of scientific computing. Iterative feedback-driven search for “good” transformation sequences is being investigated. A novel approach to parallelisation based on a unified data and loop transformation framework is presented and evaluated. Performance optimisation is achieved through exploitation of data locality on the one hand, and utilisation of DSP-specific architectural features such as Direct Memory Access (DMA) transfers on the other hand. The proposed methodology is evaluated against two benchmark suites (DSPstone & UTDSP) and four different high-performance DSPs, one of which is part of a commercial four processor multi-DSP board also used for evaluation. Experiments confirm the effectiveness of the program recovery techniques as enablers of high-level transformations and automatic parallelisation. Source-to-source transformations of DSP codes yield an average speedup of 2.21 across four different DSP architectures. The parallelisation scheme is – in conjunction with a set of locality optimisations – able to produce linear and even super-linear speedups on a number of relevant DSP kernels and applications.

Although there is considerable interest in the role of performance management systems (PMS) to enhance innovation and performance, there is limited literature regarding successful implementation in organisations. Most research has focused on the technicalities of performance management implementations, while neglecting the human reactions that influence the outcomes of such systems. This research therefore aimed to examine employees’ perceptions of performance management systems in various organisations and how performance management systems, or the lack thereof, specifically influence performance in the Namibian organisational context. A multiple case study methodology was adopted for the research, where open-ended questionnaires and semi-structured interviews were used to collect data from various organisations. Data was primarily analysed by means of qualitative content analysis which was supported by the pattern matching technique. The research findings supported goal setting theory which predicts that performance benefits can be realised by implementing specific challenging goals because they have a motivational effect on employees compared to vague and easy goals. Findings also supported theory which suggests employee participation in goal setting and providing feedback led to higher performance compared to when goals are assigned and no feedback is given. The findings supported predicted positive relationships between rewards and performance. However, findings also suggested that performance management systems, or lack thereof, are unfair because rewards are distributed unjustly, which has a negative effect on performance. Nevertheless, it was suggested that employees are more motivated to perform by intrinsic factors, including achieving challenging goals, than extrinsic factors. These findings not only supported goal setting theory, they supported McGregor’s (1960) theory Y which argued that employees are ambitious and motivated by more than money, yet surprisingly also supported his theory X as it was revealed that some employees would only work harder if rewards, or performance bonuses, are given. Although the research aimed to test goal setting theory, findings also supported Vroom’s (1964) valence-instrumentality-expectancy theory, Maslow’s (1943) and McClelland’s (1975) need theories, which all argue that performance is enhanced by other sources of motivation. The findings supported contradictory theories, yet discovered interdependency among the theories, which created a cyclical notion. This means, Vroom’s (1964) theory argues that an employee can be motivated to perform better when there is a belief that the better performance will lead to good performance appraisal and in the realisation of personal goal in the form of some reward. It, however, implies that goal setting theory has no impact on employees’ performance. Yet, according to the qualitative findings, some employees will only increase performance if their performance is monitored and appraised. Therefore organisations are required to have performance management systems in place, in turn, supporting goal setting theory. The research attempted to generate meaningful insight that would be beneficial to organisations, in and outside Namibia, that are considering implementing or improving their performance management systems by incorporating what employees perceive to be fundamentally important. Communication, management support, performance feedback, education and training, goal setting and employee participation are amongst the factors perceived as essential to effective performance management systems implementation. As literature (Bernardin & Beatty, 1984; Fox & Spector, 2002) has affirmed, these findings stress that the effectiveness of performance management systems depends on employees’ attitudes and perceptions of the systems.