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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Strategies to enhance graduate throughput of student nurses in Limpopo College of Nursing, South Africa

Neshunzhi, Ntshengedzeni Dorothy January 2018 (has links)
Thesis (M.Cur.) -- University of Limpopo, 2018 / Graduate throughput of student nurses is one of the priorities of the National Department of Health in Republic of South Africa. New nurse graduates are expected to curb the obvious shortage of nurses in the nursing profession.The purpose of the study was to design the strategies to enhance graduate throughput of student nurses. The study design was quantitative, cross-sectional descriptive, research design. The study population included all student nurses who have repeated a level of study. Probability cluster random sampling was employed to select the respondents based on the examination results for both levels. Data were collected through a self-developed questionnaire. Questionnaires were distributed to 239 respondents (167 student nurses and 72 nurse-educators were completed and returned and questionnaires were analysed) Ethical clearance was obtained from Turfloop Research Ethics Committee, Limpopo Province Department of Health Ethics Committee and Limpopo College Campuses management. The researcher ensured that measures of reliability and validity are adhered to and ethical principle for conducting research that involves human-beings was considered. Data were analysed using Statistical Package for Social Sciences (SPSS) version 23 for Windows. Descriptive statistics were used to analyse, describe and summarize data in which the findings were presented in the form of distribution tables, graphs and inferential statistics. The study revealed that poor academic performance and achievement of student nurses was caused by work overload, academic stress, anxiety, low morale, lack of dedication, prioritizing social activities and ill health.Strategies to overcome the causes of poor academic performance and achievement of student nurses were developed. The strategies are-; selection criteria, adequate resources and equipment, conducive-learning environment, student nurses counselling, student nurses discipline, academic curriculum, strategies and programs, innovative teaching strategies, expertise placement, in-service trainings, mutual student-nurse, nurse-educator relationship, adequate resources and equipment as well as awards and incentives.
12

The Secondary Users¡¦Throughput Maximization in Cognitive Radio System Under Channel Capacity Constraint

Chang, Chih-Kai 04 August 2010 (has links)
In a CR network, the maximum SUs throughput is desired generally. In this thesis, We investigate and formulate the problem of the secondary users¡¦ throughput maximization in cognitive radio systems under channel capacity constrain. By using KKT theorem, an objec- tive function is developed to obtain an optimal solution for the SU throughput maximization problem. An numerical example is also presented for illustration. The most important results revealed in the example show that the maximum SU throughput is achieved by cooperating an optimal number of SU pairs instead of cooperating all the SU pairs.
13

Impact of Network Address Translation on Router Performance

Chugh, Sarabjeet Singh 22 October 2003 (has links)
Network Address Translation (NAT) is a method by which Internet Protocol (IP) addresses are translated from one group to another, in a manner transparent to the end users. It translates the source and destination addresses and ports in the Internet Protocol datagram. There are several benefits for using NAT. NAT can be installed without changes to hosts or routers, it allows reuse of globally routable addresses, it facilitates easy migration or addition of new networks and it provides a method to keep private network addresses hidden from the outside world. NAT, however, is a processor- and memory-intensive activity for any device that implements it. This is because NAT involves reading from and writing to the header and payload information of every IP packet to do the address translation, a performance-intensive activity. It causes an increase in Central Processing Unit (CPU) and memory utilization and may impair throughput and increase the latency experienced by a packet. Thus, understanding the performance impact of NAT on a network device (in particular, a router) becomes an important factor when implementing NAT in any live network. This thesis aims to understand and quantify the impact of Network Address Translation on a network router by doing a series of performance tests after specifying the performance parameters to measure and, then, clearly defining the performance testing methodology that is used to study each of the performance parameters. After a discussion of previous research, the measurement system and subsequent measurement results are described. / Master of Science
14

Network Telemetry Link Throughput Maximization Approaches

Moodie, Myron L., Newton, Todd A., Abbott, Ben A. 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The use of Ethernet and Internet Protocol (IP) networking technologies in flight test instrumentation and telemetry systems is rapidly increasing, driven by the ubiquity, scalability, and flexibility of networking technologies. Networks first made a positive impact in ground station infrastructure and have recently been emerging in test article data acquisition infrastructure in programs such as the A380, 787, P-8A, and Future Combat Systems. The next logical step is to provide a two-way network telemetry link to fully extend the flexibility of the network between the test articles and ground station. The United States Department of Defense (DoD) integrated Network-Enhanced Telemetry (iNET) program is currently working to build a standardized network telemetry link for exactly this purpose. When developing a network telemetry link, the limited availability of telemetry spectrum must be considered and thus it is critical to choose system-level approaches to maximize the throughput achieved from the link. This paper first presents the statistics of the network data that would typically use this link based on empirical data from current network-based flight test instrumentation systems. Several approaches to using a network telemetry link are then presented. Predicted achievable throughputs of each approach are presented that are derived from the statistics of the empirical test data. Based on this, the paper presents recommendations for building systems using network telemetry links.
15

Multicarrier Diversity in Random Access Networks

Ganesan, Ghurumuruhan 12 1900 (has links)
Random access schemes are primarily used for data transmission in the uplink of cellular networks. Every user in a random access network is programmed to follow a predetermined transmit control policy that is designed to achieve optimal network performance. This approach, however, is not very efficient in cellular networks where channel conditions vary from time to time. Employing a fixed transmission policy may not guarantee optimal performance. To alleviate this problem, recently, channel aware random access schemes have been proposed wherein information available at the physical (PHY) layer is utilized at the higher layers to maximize network throughput. Such a cross-layer approach naturally has its share of challenges and problems. The objective of the proposed research is to study the effect of multicarrier diversity on channel aware random access schemes. First, we describe two generic random access schemes - channel aware multicarrier random access (CAMCRA) and no selection random access (NS-RA) for multicarrier networks. The former is based on judicious carrier selection and exploits multicarrier diversity while the latter does not perform carrier selection. For illustration purposes, we consider the well-known Aloha protocol and study the effect of channel state imperfection on the overall network throughput. We show that networks employing the NS-RA scheme are extremely sensitive to channel measurement errors. More precisely, the asymptotic average throughput of the NS-RA scheme under uncertain channel conditions is zero. The CAMCRA scheme, however, is very robust to channel estimation errors and maintains the same order of throughput.
16

Leveraging the genomics revolution with high-throughput phenotyping for crop improvement of abiotic stresses

Crain, Jared Levi January 1900 (has links)
Doctor of Philosophy / Genetics Interdepartmental Program - Plant Pathology / Jesse A. Poland / A major challenge for 21st century plant geneticists is to predict plant performance based on genetic information. This is a daunting challenge, especially when there are thousands of genes that control complex traits as well as the extreme variation that results from the environment where plants are grown. Rapid advances in technology are assisting in overcoming the obstacle of connecting the genotype to phenotype. Next generation sequencing has provided a wealth of genomic information resulting in numerous completely sequenced genomes and the ability to quickly genotype thousands of individuals. The ability to pair the dense genotypic data with phenotypic data, the observed plant performance, will culminate in successfully predicting cultivar performance. While genomics has advanced rapidly, phenomics, the science and ability to measure plant phenotypes, has slowly progressed, resulting in an imbalance of genotypic to phenotypic data. The disproportion of high-throughput phenotyping (HTP) data is a bottleneck to many genetic and association mapping studies as well as genomic selection (GS). To alleviate the phenomics bottleneck, an affordable and portable phenotyping platform, Phenocart, was developed and evaluated. The Phenocart was capable of taking multiple types of georeferenced measurements including normalized difference vegetation index and canopy temperature, throughout the growing season. The Phenocart performed as well as existing manual measurements while increasing the amount of data exponentially. The deluge of phenotypic data offered opportunities to evaluate lines at specific time points, as well as combining data throughout the season to assess for genotypic differences. Finally in an effort to predict crop performance, the phenotypic data was used in GS models. The models combined molecular marker data from genotyping-by-sequencing with high-throughput phenotyping for plant phenotypic characterization. Utilizing HTP data, rather than just the often measured yield, increased the accuracy of GS models. Achieving the goal of connecting genotype to phenotype has direct impact on plant breeding by allowing selection of higher yielding crops as well as selecting crops that are adapted to local environments. This will allow for a faster rate of improvement in crops, which is imperative to meet the growing global population demand for plant products.
17

Control System Analysis of a Telemetry Network System (TmNS)

Araujo, Maria S., Moodie, Myron L., Abbott, Ben A., Grace, Thomas B. 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / On the surface, network-based telemetry systems would appear to be simple, stateless, information collecting entities. Unfortunately, the reality of networking technologies brings a hierarchy of control loops into the system setup. At the top level, the command and status collection data loop that users manipulate the system with is a feedback loop. The commands themselves are transmitted across the network through competing streams of data, which are guided and controlled by Transmission Control Protocol (TCP) mechanisms. TCP mechanisms themselves have control loops in order to avoid congestion, provide reliability, and generally optimize flow. These TCP streams flowing across a network fabric compete at choke points, such as network switches, routers, and wireless telemetry links - all of which are also guided by control loops. This paper discusses the hierarchy of control loops present in a TmNS, provides an analysis of how these loops interact, and describes key points to be considered for telemetry systems.
18

A Platform for High-throughput Mechanobiological Stimulation of Engineered Microtissues

Beca, Bogdan 24 July 2012 (has links)
While tissue-engineering approaches of heart valves have made great strides towards creating functional tissues in vitro, the instruments used, named bioreactors, cannot efficiently integrate multiple stimuli to accurately emulate the physiological microenvironment. To address this, we conceptually designed and built a bioreactor system that applied a range of mechanical tension conditions, modulated matrix stiffness, and introduced biochemical signals in a combinatorial and high-throughput manner. Proof-of-concept experiments on PAVIC-seeded hydrogels were performed to assess the independent and combined effects of tensile strain, matrix stiffness and TGF-β1 on myofibroblast differentiation by measuring α-SMA expression, a marker that indicates a disease-associated phenotype. We found that matrix stiffness and TGF-β1 significantly increased α-SMA levels (p < 0.001), while the effect of mechanical strain was only significant on soft gels (~12 kPa) without TGF-β1. This study therefore demonstrated independent and integrated effects of multiple stimuli in regulating key cellular events in the aortic valve.
19

High throughput virtual drug screening using spherical harmonic molecular surface representations

Mavridis, Lazaros January 2009 (has links)
This thesis presents new spherical harmonic (SH) approaches for ligand-based high-throughput virtual screening (HTVS). If it is assumed that small drug molecules may be adequately superposed and distinguished by co-locating their centers of mass and by performing rotational correlations of their shapes, then to a good approximation each molecule may be represented very compactly using a two dimensional (2D) SH surface envelope. Of course, this assumes that the true molecular surface is star-like, or single-valued, with respect to radial rays projecting from the selected origin. However, this often holds to a very good approximation for small globular molecules. Even when this is not the case, it is nonetheless reasonable to suppose that similar molecules should give similar radial projections and, therefore, that they should share very similar SH representations. Following this premise, a new program called “SpotLight” was developed. The results obtained with this software show that SH-based global shape matching provides a powerful new way to perform HTVS. SH surface representations are increasingly being applied to a broad range of object recognition and registration tasks, and have also been used to model protein-ligand shape complementarity. Most current shape similarity techniques search for global similarities, and may therefore miss finding active compounds with different overall shapes and sizes but which share similar substructures or surface features. Existing molecular fragment matching algorithms can identify common covalent substructures but they are not well suited for performing scaffold-hopping shape-based database searches. This thesis introduces a novel SH fragment-based shape matching approach that can exploit knowledge of structures of existing protein-ligand complexes to perform virtual screening using as queries SH surface fragments derived from crystallographic ligand binding surfaces.
20

IP Router Testing, Isolation and Automation

Peddireddy, Divya January 2016 (has links)
Context. Test Automation is a technique followed by the present software development industries to reduce the time and effort invested for manual testing. The process of automating the existing manual tests has now gained popularity in the Telecommunications industry as well. The Telecom industries are looking for ways to improve their existing test methods with automation and express the benefit of introducing test automation. At the same time, the existing methods of testing for throughput calculation in industries involve measurements on a larger timescale, like one second. The possibility to measure the throughput of network elements like routers on smaller timescales gives a better understanding about the forwarding capabilities, resource sharing and traffic isolation in these network devices. Objectives. In this research, we develop a framework for automatically evaluating the performance of routers on multiple timescales, one second, one millisecond and less. The benefit of introducing test automation is expressed in terms of Return on Investment, by comparing the benefit of manual and automated testing. The performance of a physical router, in terms of throughput is measured for varying frame sizes and at multiple timescales. Methods. The method followed for expressing the benefit of test automation is quantitative. At the same time, the methodology followed for evaluating the throughput of a router on multiple timescales is experimental and quantitative, using passive measurements. A framework is developed for automatically conducting the given test, which enables the user to test the performance of network devices with minimum user intervention and with improved accuracy. Results. The results of this thesis work include the benefit of test automation, in terms of Return on Investment when compared to manual testing; followed by the performance of router on multiple timescales. The results indicate that test automation can improve the existing manual testing methods by introducing greater accuracy in testing. The throughput results indicate that the performance of a physical router varies on multiple timescales, like one second and one millisecond. The throughput of the router is evaluated for varying frame sizes. It is observed that the difference in the coefficient of variance at the egress and ingress of the router is more for smaller frame sizes, when compared to larger frame sizes. Also, the difference is more on smaller timescales when compared to larger timescales. Conclusions. This thesis work concludes that the developed test automation framework can be used and extended for automating several test cases at the network layer. The automation framework reduces the execution time and introduces accuracy when compared to manual testing. The benefit of test automation is expressed in terms of Return on Investment. The throughput results are in line with the hypothesis that the performance of a physical router varies on multiple timescales. The performance, in terms of throughput, is expressed using a previously suggested performance metric. It is observed that there is a greater difference in the Coefficient of Variance values (at the egress and ingress of a router) on smaller timescales when compared to larger timescales. This difference is more for smaller frame sizes when compared with larger frame sizes.

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