Les réseaux ad hoc diffèrent des réseaux filaires par la multitude de perturbation auxquels ils sont sujets. Alors qu’une rupture de lien est un événement plutôt rare sur des réseaux filaires, et généralement imputable à l’état physique du matériel intermédiaire, cet événement est courant avec les communications radio. Ceci est lié à la qualité du signal reçu de l’autre extrémité ou à la configuration de l’environnement. Les perturbations causées par l’environnement ne mènent pas seulement à une rupture d’un lien, elles peuvent avoir un impact sur la réception des données. La volatilité des liens est typique dans les réseaux sans fil alors pour les réseaux filaires ce problème est inexistant. TCP, qui est prévu pour assurer la transmission fiable des données, n’a été conçu qu’en tenant compte des contraintes des réseaux filaires. Ainsi, certains événements dans la transmission de données sans fil peuvent être mal interprétés et engendrer une mauvaise réaction de TCP. Pour améliorer la performance de TCP dans les réseaux ad hoc, l’objectif de cette thèse est double. Dans un premier temps, une étude complète des performances de TCP dans les réseaux ad hoc est dressée. Celle-ci concerne à la fois les débits atteignables et aussi la consommation d’énergie induite par l’utilisation de ce protocole de transport dans un réseau ad hoc. Cette étude permet d’identifier les points d’amélioration de TCP pour qu’il soit utilisable dans les réseaux ad hoc. Dans un second temps, nous proposons une nouvelle variante de TCP, appelée TCP-WELCOME, dont l’objectif est de traiter de façon adéquate les différents types de perte de paquets sur un réseau ad hoc et optimiser la performance de TCP. / Wireless ad hoc networks are different from wired networks by the multitude of data packet loss situations they are subjected to. This is due to the characteristics of wireless channel that might obstruct the proper reception of data packet at the destination end. In some case, these vulnerabilities of wireless channel can result in a complete link failure. Although link failure is of low probability in wired networks, it is rather common in wireless networks. The volatility of communication channel is a typical problem with wireless links, which is not the case with wired cables. TCP is a transport protocol that aims at ensuring high reliability and guarantying reception of data packets. However, TCP was designed for wired networks to address congestion, which is the main cause for data packet loss in wired networks. Therefore, other types of data packet loss encountered in wireless networks are prone to misinterpretation by TCP, which will lead to TCP performance degradation within the network. To overcome the performance limitation of TCP when used within ad hoc networks, the aim of this thesis is twofold. First, a complete performance study of TCP over ad hoc networks is achieved. This evaluation concerns two performance metrics: the achievable throughput and the energy consumption of TCP within ad hoc networks. This study allows identifying the potential room of improvement to enhance TCP efficiency in ad hoc networks. Second, we propose a new TCP variant, TCP-WELCOME that optimizes the performance of TCP in ad hoc networks through its ability to distinguish among, and efficiently deal with, different data packet loss situations, within ad hoc networks.

Thesis (MTech (Business))--Peninsula Technikon, 2003. / Word processed copy. Summary in English. Includes bibliographical references (leaves 132-140). Also available online

Performance regression refers to the phenomena where the application performance degrades compared to prior releases. Performance regressions are unwanted side-effects caused by changes to application or its execution environment. Previous research shows that most problems experienced by customers in the field are related to application performance. To reduce the likelihood of performance regressions slipping into production, software vendors must verify the performance of an application before its release. The current practice of performance verification is carried out only at the implementation level through performance tests. In a performance test, service requests with intensity similar to the production environment are pushed to the applications under test; various performance counters (e.g., CPU utilization) are recorded. Analysis of the results of performance verification is both time-consuming and error-prone due to the large volume of collected data, the absence of formal objectives and the subjectivity of performance analysts. Furthermore, since performance verification is done just before release, evaluation of high impact design changes is delayed until the end of the development lifecycle. In this thesis, we seek to improve the effectiveness of performance verification. First, we propose an approach to construct layered simulation models to support performance verification at the design level. Performance analysts can leverage our layered simulation models to evaluate the impact of a proposed design change before any development effort is committed. Second, we present an automated approach to detect performance regressions from results of performance tests conducted on the implementation of an application. Our approach compares the results of new tests against counter correlations extracted from performance testing repositories. Finally, we refine our automated analysis approach with ensemble-learning algorithms to evaluate performance tests conducted in heterogeneous software and hardware environments. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-01-31 15:53:02.732

Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains x, 253 p. Includes bibliographical references (p. 235-253). Available online via OhioLINK's ETD Center

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Pallets form the base of the unit load, which is the basis for global trade transportation. In order to achieve better performance, improve efficiency, and compete in much more versatile markets, industrial activities and pallet management service firms are becoming more automated than ever; they are adopting advanced manufacturing technologies and flexible manufacturing systems. This study focuses on the investigation of the most common compatibility issues between pallets and material handling systems in semi-automated and fully-automated warehouses. At the same time, it establishes an understanding of the downtime and frequency of problems caused by pallets in these types of facilities. This research was conducted in two phases. The primary phase was a mix mode questionnaire (phone interview and hard copy questionnaire) that was used to survey members of different industries, such as pallet manufacturers, equipment manufacturers, and pallet users. The secondary phase surveyed multiple general warehouses and storage facilities around the U.S., and surveyed warehouse professionals from manufacturing companies in the pharmaceutical, petroleum, dairy, beverage, chemical, and tobacco industries, to name a few. Results showed that 3% of the respondent warehouses are fully automated, and 20-30 % are semi-automated. Additionally, block class wooden pool pallets were identified as the most common pallet class used in semi/fully automated warehouses, followed closely by the use of stringer class recycled wooden pallets. Despite this, stringer class recycled wooden pallets were identified as the main pallet class involved in pallet related downtime in semi/ fully automated warehouses/ DC facilities. Further results present a guideline for improving automated warehouse performance, determine the pallet characteristics needed for this type of application, and expands the knowledge around downtime frequency cause by pallet related issues in these types of systems. / Master of Science / Pallets are the main tool used to transport unit loads throughout the different supply chains worldwide. Currently, industrial activities are becoming more automated than ever; in order to achieve better performance, improve efficiency, and compete in much more versatile markets. This study investigates the most common compatibility issues between pallets and material handling systems, used in semi-automatic and fully-automatic warehouses. Additionally, it presents the downtime and frequency of problems caused by pallets in these types of facilities. This research was conducted in two phases. The first phase identified the most common compatibility issues between pallets and these types of systems; this phase was achieved by surveying members of different industries such as pallet manufacturers, equipment manufacturers, and pallet users. The second phase targeted multiple general warehouses and storage facilities around the U.S.; during this phase, the frequency and downtime of the most common compatibility issues were determined. Results from this investigation present a guideline for improving automatic warehouse performance, determine the pallet characteristics needed for this type of application, and expands the knowledge around downtime frequency cause by pallet related issues in these types of systems.

Thesis (MPA)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Anita Endsley will portray the role of Sister Mary Hubert in the musical Nunsense at Seaside Music Theatre in Daytona Beach, Florida from October 28 through November 14, 2005. This parody of convent life in crisis written by Dan Goggin provides a breadth of material for analysis of the genre as well as character analysis. Dissecting the comedy will be the foundation for characteer development. The popularity of this musical among Catholic and non-Catholic audiences have created a market that inspired the writer to extend this theme through five sequels. The commercial success of these musicals suggest a strong connection between the demands of the Catholic doctrine and the foundation for comic relief. A vast amount of research can be incorporated to assist in the analysis of comedy written into Nunsense.

No / This paper aims to evaluate the aims and methods of appraisal, and the difficulties encountered in the appraisal process. The paper uses a review of the literature to evaluate the development of appraisals and argues that the critical area of line management development that was identified as a critical success factor in appraisals has been ignored in the later literature evaluating the effectiveness of performance appraisals. The review identifies the lack of theoretical development in appraisal and argues the psychological approach of analysis and a more critical realisation of appraisal, re‐evaluating the challenge to remove subjectivity and bias in judgement of appraisal. Further evaluation of key interpersonal skills is required for appraisal systems to develop performance. The use and design of performance pay in public and private services linked to appraisal have not always improved organisational performance and can contribute to reduced motivation. Little research has evaluated the current increases in using appraisals and the changes in focus from appraisal to performance management. The paper adds value to the existing body of knowledge and offers insights for practitioners and researchers.

This dissertation defined employee performance and the challenges experienced by each individual employee during the operation setting. All the factors such as the conditions, tools used and understanding the setting are being researched. Despite this, the clear multidisciplinary approach, the field of performance management has developed from diverse origins. Different measurement and management techniques and approaches have developed independently. Personnel (or HR) have been concerned with managing the performance of people. Performance management from these disparate disciplines has begun to converge and recognize the need for integration into a multidisciplinary approach to managing performance. The management discipline which most often associates itself with the term is in Human Resources. Performance management is often associated with the management of the performance of people. However, in the HR field the best practice emphasizes the contribution of people to the achievement of organizational performance. From the HR field Armstrong and Baron highlight the importance of performance management being strategic, integrated (vertical, functional, HR integration and integration of individual needs), concerned with performance improvement and concerned with development. Performance management should be integrated horizontally across the organization; The performance being managed should reflect the requirements, wants and needs of all of the key stakeholders of the organization and not just reflect a limited set. Performance management should be integrated vertically linking the strategies and objectives of the organization to the execution of activities which will enable their achievement. Explicit understanding of linkages across the vertical and horizontal integration (e.g. through success maps) enables consideration of conflicting priorities and trade-offs that need to be made in order to achieve overall objectives. The performance monitoring, review and action planning process should be structured around the strategic performance objectives of the organization. / Thesis (MBA) North-West University, Mafikeng Campus, 2013