Literature on financial statement analysis has been documented by various authors on how the performances of organisations can be measured using financial statement analysis as a tool. Most of the literature focused on what has been written in relating to organisations which are listed on the stock exchange. However, the same principles which are applied in evaluating the performance of large organisations can equally be applied to any organisation; this includes small and medium-sized enterprises operating in Namibia. Despite the fact that financial statement analysis is an important tool for evaluating the performance of organisations, no previous literature was found pertaining to the evaluation of the performance of Namibian small and medium-sized enterprises using this tool. This research will attempt to identify how management of Namibian small and medium-sized enterprises can effectively make use of financial statement analysis as a tool in evaluating the performance of the organisations in order to make correct strategic decisions that will benefit the SMEs.

Underwater wireless sensor networks (UWSNs) are the enabling technology for a new era of underwater monitoring and actuation applications. However, there still is a long road ahead until we reach a technological maturity capable of empowering high-density large deployment of UWSNs. To the date hereof, the scientific community is yet investigating the principles that will guide the design of networking protocols for UWSNs. This is because the principles that guide the design of protocols for terrestrial wireless sensor networks cannot be applied for an UWSN since it uses the acoustic channel instead of radio-frequency-based channel. This thesis provides a general discussion for high-fidelity and energy-efficient data collection in UWSNs. In the first part of this thesis, we propose and study the symbiotic design of topology control and opportunistic routing protocols for UWSNs. We propose the CTC and DTC topology control algorithms that rely on the depth adjustment of the underwater nodes to cope with the communication void region problem. In addition, we propose an analytical framework to study and evaluate our mobility-assisted approach in comparison to the classical bypassing and power control-based approaches. Moreover, we develop the GEDAR routing protocol for mobile UWSNs. GEDAR is the first OR protocol employing our innovative depth adjustment-based topology control methodology to re-actively cope with communication void regions. In the second part of this thesis, we study opportunistic routing (OR) underneath duty-cycling in UWSNs. We propose an analytical framework to investigate the joint design of opportunistic routing and duty cycle protocols for UWSNs. While duty-cycling conserves energy, it changes the effective UWSN density. Therefore, OR is proposed to guarantee a suitable one-hop density of awake neighbors to cope with the poor and time-varying link quality of the acoustic channel. In addition, we propose an analytical framework to study the impact of heterogeneous and on-the-fly sleep interval adjustment in OR underneath duty-cycling in UWSNs. The proposed model is aimed to provide insights for the future design of protocols towards a prolonged UWSN lifetime. The developed solutions have been extensively compared to related work either analytically or through simulations. The obtained results show the potentials of them in several scenarios of UWSNs. In turn, the devised analytical frameworks have been providing significant insights that will guide future developments of routing and duty-cycling protocols for several scenarios and setting of UWSNs.

The ability to make realistic judgements of one’s performance is a demonstration of the possession of strong metacognitive skills. Metacognition involves the monitoring of one’s progress during learning, and the ability to modify learning strategies for increased effectiveness. Poor-performing students are at risk because they generally exhibit high levels of overconfidence when evaluating their performance, and may fail to adjust their learning strategies in time. This study aims to explore the accuracy with which students in the BSc Four-year programme (BFYP) of the University of Pretoria evaluate their performance in a stoichiometry test, as well as the influence of teaching on test performance and on accuracy of performance evaluation. The factors that students rely on when making performance evaluations as well as shifts in the reliance on these factors after teaching are explored. Finally, the study examines the relationship between bias in performance evaluation and the self-protection, self-enhancement motivational factors and gender. Data were collected by means of a three-tier stoichiometry test instrument, administered as pre- and posttest, as well as a questionnaire administered simultaneously with the pretests to a sample of 91 students. Each test item comprised a stoichiometry question, a confidence rating and a free-response explanation for the choice of confidence rating. The confidence rating was interpreted as an indication of expected performance. The test instrument allowed for the investigation of bias in performance evaluation in the pre- and posttests, the exploration of factors that students rely on when making performance evaluations and how the reliance on these factors shifted in the posttests. The questionnaires were used to collect data on self-enhancement, self-protection and gender. The study shows that the majority of the students were overconfident in the evaluation of their performance in both the pre- and posttests. Performance improved significantly in the posttest but accuracy of performance evaluation did not. Students were categorised as overconfident (OC), realistic (R) or under-confident (UC) based on the difference between actual and expected performance. Five subgroups were defined on the basis of accuracy of performance evaluation in the pre- and posttests. The five subgroups, labelled first by their pretest and then their posttest category, were the OC-OC (50 students), OC-R (13 students), R-R (11 students), R-OC (15 students) and the R-UC (2 students) subgroups. The results indicated no significant difference between the pre-knowledge and ability of the students in the four main subgroups. The students differed significantly in terms of performance in the posttest, their pre- and posttest average confidence scores and in performance gain. A significant difference was not found with regard to performance in the CMY 143 end of semester examination. These findings confirmed that we were dealing with four discrete subgroups with different characteristics. The OC-R subgroup achieved the highest learning gain by a significant margin. Moderate learning gains were demonstrated by the R-R and OC-OC subgroups and the R-OC subgroup did not achieve any learning gain at all. Careful analysis of qualitative data revealed that accuracy in the evaluation of posttest performance was associated with both a reduction in the prevalence of vague subjective judgments and with higher performance gain. Similarly, an increase in the tendency to base metacognitive monitoring on vague global judgments of performance in the posttest was associated with reduced accuracy of self-evaluation and lower learning gain. The tendency by the four performance evaluation subgroups to self-enhance or self-protect was not found to be statistically different. P-values greater than 0.05 in the pre- and posttests indicated that males and females were not significantly different in their accuracy of performance evaluation. The study suggests that an element of bias in performance evaluation may be beneficial to learning. Inaccuracy in self-evaluation in the pretest did not hamper learning for both the OC-OC and OC-R subgroups. Students who were over-optimistic about their performance in the pretest may have been less intimidated by the challenges of the new content material than those who were better calibrated (R-R and R-OC subgroups). Students who remained overconfident in the posttest, i.e. in the OC-OC subgroup did not gain from the learning experience as much as those who entered overconfident but became better calibrated. Those who entered tentatively as realists and then, with a little exposure, became unrealistic in their performance evaluation were shown to be the most vulnerable based on their lack of learning gain. Furthermore, increasing content knowledge alone may not be enough to raise the metacognitive ability of students. Finally, chemistry educators should be aware that students often make vague subjective judgements of performance even on a topic like stoichiometry, which requires predominantly procedural knowledge and formal reasoning. Our study has shown that this deficiency, when associated with poor accuracy of self-evaluation, may hamper learning gain. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Chemistry / unrestricted

To support increasingly sophisticated sensors and resource-hungry applications with the current-used Lithium-based batteries and to augment mobile computing power further, the concept of the Cloudlet-based offloading is proposed which enables to migrate part of application computing tasks from battery-limited low-capacity mobile elements to the local edge. Such Cloudlet-based offloading technologies extend the provisioning of computing and storage capabilities from remote Cloud Data Centers to the proximity of end users via heterogeneous networks. However, Cloudlet-based offloading is required to coordinate among User Equipment, inter-Cloudlet nodes and remote Cloud Data Centers, which emerges new challenges and issues regarding how to enable Cloudlet-based offloading in the context of mobile edge environment and how to achieve execution- and energy-efficient offloading allocation under limited available resources. In this dissertation, a Cloudlet-based Mobile Cloud offloading prototype is first proposed. A mechanism for handling diverse computing resources is described; by adopting it, idle public resources can be easily configured as additional computing capabilities in the virtual resource pool. A fast deployment model is built to relieve the migration and installation cost when adapting the platform. An energy-saving strategy is utilized to reduce the consumption of computing resources. Security components are implemented to protect sensitive information and block malicious attacks in the cloud. Concerning the limited processing capability on the edge, a task-centric energy-aware Cloudlet-based Mobile Cloud model is formulated. A Cloudlet task-based offloading mechanism is proposed to achieve energy-aware offloading resource preparation and scheduling on the Cloudlet. A Cloud task-centric scheduling algorithm is presented for the green collaborative offloading processing between Cloudlet and remote Cloud. Considering the dynamic and heterogeneity of the offloading environment, a hybrid offloading model to solve the heterogeneous resource-constraint offloading issues on the dynamic Cloudlets. A queue-based offloading framework is developed to formulate and analyze the mixed migration-based and partition-based offloading behaviours on the Cloudlet. The execution and energy-aware heterogeneous offloading resource allocation problem is formalized and solved. A time series-based load prediction model is designed on the Cloudlet to achieve fine-grain proactive resource allocation. Regarding the mobility of User Equipment and the diverse priority of offloading tasks, an edge-based mobility-aware offloading model is modeled to solve the intra-Cloudlet offloading scheduling issue and inter-Cloudlet load-aware heterogeneous resource allocation issue. A priority-based queueing model is designed to formulate the intra-Cloudlet mobility-aware offloading scheduling problem, resolved by a heuristic solution. The energy-aware inter-Cloudlet resource selection procedure is formalized in a mobility-aware multi-site resource allocation model, which is further solved by lightweight dynamic load balancing.

abstract: Relative performance evaluation (RPE) in Chief Executive Officer (CEO) compensation contracts entails the use of peer performance to filter out exogenous shocks and reduce exposure to risk. Theory predicts that high-quality peers can effectively filter out noise from performance measurement, yet prior empirical studies do not examine how differences in peer quality affect the use of RPE in practice. In this study, I propose a model to select peers with the highest capacity to filter out noise and introduce a novel measure of peer quality. Consistent with the theory, I find that firms with high quality peers rely on RPE to a greater extent than firms with few good peers available. I also examine the extent to which peers disclosed in proxy statements overlap with the best peers predicted by my model. I find that the overlap is positively associated with institutional ownership, use of top 5 compensation consultants, and compensation committee competence. / Dissertation/Thesis / Doctoral Dissertation Accountancy 2020

In this paper, we consider the peer-to-peer transfer of popular files between devices in a wireless mesh network. We address the problem that occurs when multiple nodes try to access the same file simultaneously, resulting in increased contention on the shared wireless channel. To counteract this problem, we propose a cooperative file transfer protocol which splits a file into fixed-sized pieces and allows simultaneous downloads of such pieces from multiple peers. Opposed to previous approaches, the proposed protocol selects the potential download peers such that the corresponding download paths possess minimum interference among each other. In a performance study where we compare our approach with other download schemes proposed in the literature, we show that our cooperative protocol roughly halves the time required for downloading a file.

<div><div><div><p>The increasing cost of cloud services and the need for decentralization of servers has led to a rise of interest in edge computing. In recent years, edge computing has become a popular choice for latency-sensitive applications like facial recognition and augmented reality because it is closer to the end users compared to the cloud. However, the presence of multiple edge servers adversely affects the reliability due to difficulty in maintenance of heterogeneous servers. In this thesis, we first evaluate the performance of various server configuration models in edge computing using EdgeCloudSim, a popular simulator for edge computing. The performance is evaluated in terms of service time and percentage of failed tasks for an Augmented Reality application. We evaluated the performance of the following edge computing models, Exclusive: Mobile only, Edge only, Cloud only; and Hybrid: Edge & Cloud hybrid with load-balancing on the Edge, and Mobile & Edge hybrid. We analyzed the impact of variation of different parameters such as WAN bandwidth, cost of cloud resources, heterogeneity of edge servers, etc., on the performance of the edge computing mod- els. We show that due to variation in the above parameters, the exclusive models are not sufficient for computational requirements and there is a need for hybrid edge computing models. </p><p>Next, we introduce a novel edge computing model called unmanaged edge computing and propose an orchestration scheme in this scenario. Although infrastructure providers are working toward creating managed edge networks, personal devices such as laptops, desktops, and tablets, which are widely available and are underutilized, can also be used as potential edge devices. We call such devices Unmanaged Edge Devices (UEDs). Scheduling application tasks on such an unmanaged edge system is not straightforward because of three fundamental reasons—heterogeneity in the computational capacity of the UEDs, uncertainty in the availability of the UEDs (due to the devices leaving the system), and interference among multiple tasks sharing a UED. In this work, we present I-BOT, an interference-based orchestration scheme for latency sensitive tasks on an Unmanaged Edge Platform (UEP). It minimizes the completion time of applications and is bandwidth efficient. I-BOT brings forth three innovations. First, it profiles and predicts the interference patterns of the tasks to make scheduling decisions. Second, it uses a feedback mechanism to adjust for changes in the computational capacity of the UEDs and a prediction mechanism to handle their sporadic exits, both of which are fundamental characteristics of a UEP. Third, it accounts for input dependence of tasks in its scheduling decision (such as, two tasks requiring the same input data). To demonstrate the effectiveness of I-BOT, we run real-world unit experiments on UEDs to collect data to drive our simulations. We then run end-to-end simulations with applications representing autonomous driv- ing, composed of multiple tasks. We compare to two basic baselines (random and round-robin) and two state-of-the-arts, Lavea [SEC-2017] and Petrel [MSN-2018] for scheduling these applications on varying-sized UEPs. Compared to these baselines, I-BOT significantly reduces the average service time of application tasks. This reduction is more pronounced in dynamic heterogeneous environments, which would be the case in a UEP.</p></div></div></div>

It is well known that TCP performs poorly in wireless mesh networks. There has been intensive research in this area, but most work uses simulation as the only evaluation method; however, it is not clear whether the performance gains seen with simulation will translate into benefits on real networks. To explore this issue, we have implemented ATP (Ad-hoc Transport Protocol), a transport protocol designed specifically for wireless ad hoc networks. We have chosen ATP because it uses a radically different design from TCP and because reported results claim significant improvement over TCP. We show how ATP must be modified in order to be implemented in existing open-source wireless drivers, and we perform a comprehensive performance evaluation on mesh testbeds under different operating conditions. Our results show that the performance of ATP is highly sensitive to protocol parameters, especially the epoch timeout value. To improve its performance we design an adaptive version that utilizes a self-adjustable feedback mechanism instead of a fixed parameter. A comprehensive measurement study demonstrates the advantages of our adaptive ATP under various operating conditions. For networks with high bit-rate, low quality links, our adaptive version of ATP demonstrates an average of more than 50% gain in goodput over the default ATP for a single flow case. With respect to fairness, the adaptive ATP generally outperforms the default ATP by an order of magnitude in most results.

Although there is substantial literature on the use of performance appraisal in the for-profit world, there is little literature available concerning the appraisal of staff positions in higher education. More knowledge is needed in this area since there is considerable research indicating that performance appraisal creates benefits to an organization and its employees. This study provides a comprehensive review of the development and use of performance appraisal in the United States, and a detailed look at the purposes, benefits, and challenges of performance appraisal. The study found a very high usage of staff performance appraisal in its population of 108 Christian colleges and universities. However, it also found a significant amount of dissatisfaction with the appraisal process due to (a) lack of leadership support for the appraisal process, (b) supervisors not being held accountable for the timely completion of their appraisals, and (c) the lack of training provided supervisors for doing performance appraisals well.

No / In the future mobile network, satellites will operate alongside cellular networks in order to provide seamless connectivity irrespective of the location of the user. Such a service scenario requires that the next generation of mobility management (MM) procedures are able to ensure terminal and user mobility on a global scale. This paper considers how the principles of Mobile-IP can be used to develop MM procedures for a heterogeneous access network, comprizing of satellite and cellular elements, connected to an IP core network.Initially, the system architecture is described. This is followed by a discussion of issues related to MM, where location, address and handover management are considered. A description of the signaling protocols for macro-mobility using Mobile-IP is then presented, emphasizing the need to minimize the change to the existing access network procedures. Finally, the performance of the protocols is analyzed in terms of the additional signaling time required for registration and handover.