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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.
321

Nature of spelling errors of grade three isiXhosa background learners in English first additional language

Mpiti, Thandiswa January 2012 (has links)
A central concern of education internationally and in South Africa is to develop children's literacy skill. However a literacy crisis exists in spite of efforts to counter this. Some researchers have explored the issue of literacy focusing on second language learners‟ spelling in English as Additional Language. There is, however, insufficient literature that looks into spelling experiences of isiXhosa background learners in English First Additional Language. Hence this study investigated the nature of spelling errors of Grade three isiXhosa background learners in English First Additional Language. In understanding the nature of spelling errors of Grade three isiXhosa background learners, the features of words that learners find difficult to spell and the features of words that learners find easy to spell were investigated. Moreover, learners' barriers in acquiring spelling skills in English First Additional Language and teacher practices for teaching spelling were examined. In exploring these issues the study adopted a qualitative approach in order to ensure reliability and validity of the study. The data gathering process was in the form of semi-structured interviews, classroom observations and document analysis. One isiXhosa medium primary school in a Black Township in Buffalo City Municipality in the East London District was purposively selected to form the context of the study. In this school English is taught as a subject in grade three. Participants were eight grade three learners and one Grade three class teacher who teaches these learners. The findings of the study revealed that learners with an isiXhosa background seemed to be struggling with understanding basic English words and terms. This is exacerbated by the fact that the learners seemed to struggle to understand the rules of the English language. The words that learners find difficulties in to spell in English Second Language were diagraphs. Barriers to spelling were influenced, among other issues, by learners' pronunciation and their heavy reliance on their mother tongue.
322

Erreurs humaines en aéronautique : une étude du lien entre attention et erreurs / Human error in aviation : an investigation of the links between attention and errors

Debroise, Xavier 05 July 2010 (has links)
Dans le domaine aéronautique, comme dans de nombreux autres domaines de la vie courante ou professionnelle, les erreurs ont souvent été associées à des défaillances attentionnelles. Nos travaux s’insèrent dans cette problématique, et sont plus particulièrement focalisés sur les variations de la capacité à allouer son attention sur une tâche donnée à la suite d’une interruption. Dans un premier temps, nous avons mis en place des expérimentations qui permettent d’évaluer l’étendue des variations de performances obtenues dans une tâche à la suite d’une interruption, en fonction des composantes attentionnelles sollicitées dans la tâche à exécuter. Dans un second temps, nous avons mis en place un indicateur fiable et objectif mettant en évidence des différences dans le fonctionnement physiologique cérébral en fonction de ces composantes attentionnelles. Dans un troisième temps, nous avons été amenés à vérifier l’effet de diverses interruptions dans des situations aéronautiques réalistes. Nos travaux permettent de conclure à l’existence de fluctuations de l’attention à la suite d’une interruption, fluctuations dont la conséquence peut se traduire par des variations de performances et par différentes stratégies de gestion des erreurs et des activités. / In the aviation field, as in many other areas of personal or professional life, errors have often been associated with attentional failures. Our work is related to this issue, and is more particularly focused on variations of attention following an interruption. In a first step, we have set up experiments to measure changes in performance obtained in a task after an interruption. These variations are studied systematically according to various attentional components requested in the task at hand. In a second step, we have set up an indicator showing differences in the physiological functioning of the brain depending on these attentional components. Thirdly, we have tested the effect of various interruptions in realistic aeronautical situations. From our work, we conclude that there is a variation in attention after an interruption, the consequences of which can result in errors, performance variations, and differences in the management of errors and activities.
323

Self-repair in second language interaction: Dyad groups in action

Rangel-Studer, Beatriz 01 January 2006 (has links)
Describes the results of a research project that analyzes the interaction of a second language (L2) learners of English (non-native speakers (NNS)) with a native speakers (NS). The subjects of the study were four NNS and two NS of English at Imperial Valley College in Imperial, California. The first aspect of the analysis determines the way in which self-repair might be related to L2 development and the L2 learner's language proficiency level. The second aspect of the analysis determines whether the NNS use self-repair differently when the interlocutor is a NS or a NNS of English. Results of the study indicate that while there was not a correlation between overall frequency of self-repair and language proficiency, there was a relationship between frequency of particular types of repair and language proficiency.
324

Analýza obsahových a grafických chyb kartografických děl / Analysis of content- and graphical errors of cartographic works

Chalupková, Klára January 2016 (has links)
The intention of the diploma thesis is an analysis of errors and oversights of analogue and digital cartographic works. The first part of the thesis deals with errors and oversights which are the most common in cartographic works. The second part of the thesis deals with analysis of chosen cartographic works that display Boskovice. In the end of this thesis was made a presentation and in presentation are the most often errors in cartographic works. This presentation will be used for teaching purposes for subject Cartography.
325

On the Performance Analysis of Free-Space Optical Links under Generalized Turbulence and Misalignment Models

Al-Quwaiee, Hessa 11 1900 (has links)
One of the potential solutions to the radio frequency (RF) spectrum scarcity problem is optical wireless communications (OWC), which utilizes the unlicensed optical spectrum. Long-range outdoor OWC are usually referred to in the literature as free-space optical (FSO) communications. Unlike RF systems, FSO is immune to interference and multi-path fading. Also, the deployment of FSO systems is flexible and much faster than optical fibers. These attractive features make FSO applicable for broadband wireless transmission such as optical fiber backup, metropolitan area network, and last mile access. Although FSO communication is a promising technology, it is negatively affected by two physical phenomenon, namely, scintillation due to atmospheric turbulence and pointing errors. These two critical issues have prompted intensive research in the last decade. To quantify the effect of these two factors on FSO system performance, we need effective mathematical models. In this work, we propose and study a generalized pointing error model based on the Beckmann distribution. Then, we aim to generalize the FSO channel model to span all turbulence conditions from weak to strong while taking pointing errors into consideration. Since scintillation in FSO is analogous to the fading phenomena in RF, diversity has been proposed too to overcome the effect of irradiance fluctuations. Thus, several combining techniques of not necessarily independent dual-branch free-space optical links were investigated over both weak and strong turbulence channels in the presence of pointing errors. On another front, improving the performance, enhancing the capacity and reducing the delay of the communication link has been the motivation of any newly developed schemes, especially for backhauling. Recently, there has been a growing interest in practical systems to integrate RF and FSO technologies to solve the last mile bottleneck. As such, we also study in this thesis asymmetric an RF-FSO dual-hop relay transmission system with both fixed and variable gain relay.
326

Examining Speech Production in Children with Cleft Palate with or without Cleft Lip: An Investigation of Characteristics related to Speech Articulation Skills

January 2020 (has links)
abstract: Children with cleft palate with or without cleft lip (CP+/-L) often demonstrate disordered speech. Clinicians and researchers have a goal for children with CP+/-L to demonstrate typical speech when entering kindergarten; however, this benchmark is not routinely met. There is a large body of previous research examining speech articulation skills in this clinical population; however, there are continued questions regarding the severity of articulation deficits in children with CP+/-L, especially for the age range of children entering school. This dissertation aimed to provide additional information on speech accuracy and speech error usage in children with CP+/-L between the ages of four and seven years. Additionally, it explored individual and treatment characteristics that may influence articulation skills. Finally, it examined the relationship between speech accuracy during a sentence repetition task versus during a single-word naming task. Children with CP+/-L presented with speech accuracy that differed according to manner of production. Speech accuracy for fricative phonemes was influenced by severity of hypernasality, although age and status of secondary surgery did not influence speech accuracy for fricatives. For place of articulation, children with CP+/-L demonstrated strongest accuracy of production for bilabial and velar phonemes, while alveolar and palatal phonemes were produced with lower accuracy. Children with clefting that involved the lip and alveolus demonstrated reduced speech accuracy for alveolar phonemes compared to children with clefts involving the hard and soft palate only. Participants used a variety of speech error types, with developmental/phonological errors, anterior oral cleft speech characteristics, and compensatory errors occurring most frequently across the sample. Several factors impacted the type of speech errors used, including cleft type, severity of hypernasality, and age. The results from this dissertation project support previous research findings and provide additional information regarding the severity of speech articulation deficits according to manner and place of consonant production and according to different speech error categories. This study adds information on individual and treatment characteristics that influenced speech accuracy and speech error usage. / Dissertation/Thesis / Doctoral Dissertation Speech and Hearing Science 2020
327

Syllabus errorum a vybrané dokumenty II. vatikánského koncilu / The Syllabus Errorum and Selected Documents of the Second Vatican Council

Lejsal, Tomáš January 2016 (has links)
The Syllabus Errorum and Selected Documents of the Second Vatican Council The central part of the thesis is a comparison of the document Syllabus Errorum and the documents of the Second Vatican Council. This is preceded by a first section with a comparison of the periods and circumstances in which the two documents came into being. In the following section I provide a summary of the selected literature on this theme. The comparison of the two documents proper, divided up according to logical connections, forms the main section. In the final section I reflect on the general principles and consequences arising out of the preceding comparison and I summarise the conclusions I have come to and look to see how they are reflected in current developments.
328

The effects of constraints on the performance of actively managed funds in relation to their benchmark indices

Eiselen, Linda Minette January 2018 (has links)
Actively-managed funds have recently come under fire as it has been determined that they consistently underperform passive funds. Benchmarking, and the constraints placed on actively-managed funds, are standard practices within the industry, but research suggests that these constraints negatively affect fund performance. This research paper explores the effectiveness of actively-managed funds in relation to their benchmark indices, in terms of tracking errors and weighting constraints. This is done by qualifying the effect of these constraints on the performance of hypothetically constructed portfolios in relation to the FTSE / JSE Top 40 Index. The results are presented graphically and show that tracking error limits did, as expected, limit the possible upside returns of these funds. It was found however, that the tracking error constraints had a much greater effect on limiting downside risk than they had on limiting upside effects. Weighting limitations did not have a single universal effect on the simulated portfolios’ performance but affect performance in conjunction with tracking error limits. It was concluded that for the hypothetically constructed portfolios for the period studied, constraints did not affect the possible upside return to such a magnitude that the constraints themselves could account for the underperformance of actively managed funds and they had an overall positive effect on performance. / Mini Dissertation (MBA)--University of Pretoria, 2018. / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted
329

Simulation of the MAC Portion of IEEE 802.11 and Bursts of Errors for Wireless Data Networks

Moslehi, Farhood 28 August 1997 (has links)
The focus of this research is to investigate the effects of bursts of errors and packet collisions on the performance of the medium access control (MAC) portion of the IEEE 802.11 wireless local area network (LAN) protocol.An important ingredient in rapid expansion of wireless networks is the seamless transition between wired and wireless systems. The IEEE standards group in charge of developing the widely used IEEE 802.3 LAN standard has developed the IEEE 802.11 wireless LAN standard. IEEE 802.11 remains hidden from the upper levels of the network, thus allowing a seamless transition between networks. The foundation protocol for the IEEE 802.11 standard, known as Distributed Foundation Wireless Medium Access Control (DFWMAC), operates at the MAC level of the Data Link Layer. The protocol bases its access control mechanism on a principle called Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), which is an adaptation of the Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol used by IEEE 802.3 standard. The collision avoidance scheme in CSMA/CA allows data packets to be transferred via the wireless medium with lower probability of packet collision. In a slotted multi-access wireless system, performance parameters are affected by the bit error rates on the communication channel. These errors occur as a result of noise introduced by the radio channel or data packet collisions. Collisions occur when two or more stations select the same time slot to transmit their data, thus causing corruption in data packets. In this research, a simulation model coded in Microsoft's Visual Basic programming environment is utilized to investigate the effects of bit errors and packet collisions on performance in CSMA/CA. Performance parameters used in this study include throughput, medium utilization, collisions and station data queue lengths. In the simulation model, error bursts in the communication channel are modeled using a simple Gilbert model with two states, good (G) and bad (B). State G is error free, thus errors can only occur while the model is in state B. Collisions are simulated by two or more stations starting to transmit data packets in the same time slot. Therefore, as the number of stations increases, more and more stations compete for the medium, resulting in an increase in the number of collisions. Collisions are also increased by the amount of traffic that each station introduces into the system. Station load is defined here as the number of data packets per unit time that are released by the higher network protocol layers.The results in Chapter 5 demonstrate that higher network throughput can be achieved when the aggregate load on the network is distributed. For example, 30 stations offering 20 kilobits per second (kbps) of load for a total of 600 kpbs, results in a network throughput of 585 kbps. However, three stations offering 200 kbps of load for a total of 600 kbps offered load, results in a network throughput of 486 kbps. The distributed load is serviced at a 17 percent higher rate. However, once the network becomes saturated at above 40 stations for this model, collisions will more than offset the performance gains produced by the distribution of load.Furthermore, reducing the packet size by 50 percent under an approximately 19.5 percent packet error rate results in a 12 percent gain in throughput. This is primarily due to higher utilization of the network by shorter packets. However, as the packet error rate is reduced, the performance gap between the two packet sizes is reduced. Once the errors are removed completely from the communications channel, the longer packets produce a higher throughput than the shorter packets. / Master of Science
330

Characteristics of children with medical complexity experiencing medication ordering errors at hospital admission

Akula, Vinita 03 July 2018 (has links)
Medication errors make up a staggering portion of medical error in the United States. These medication errors are most likely to occur at transitions in care. Children with medical complexity (CMC) often rely on multiple medications to maintain their health, making accurate medication ordering of utmost importance to avoid exacerbating chronic conditions or unnecessary harm. Because of their increased medication usage, CMC have an increased risk of medication ordering error (MOE). To better inform the medication reconciliation process for CMC, we examine the prevalence, category, and risk factors of MOE at hospital admissions for this patient population. A retrospective cohort analysis of 1,237 hospitalized CMC from two tertiary pediatric teaching hospitals with clinical care services for CMC was performed on data from November 1, 2015 to October 31, 2016. Pharmacists and advance nurse practitioners identified MOEs at admissions through medical record review, patient history at interview, and inpatient team discussions. Identified MOEs were classified as one of seventeen different categories, some of which include duplications, omissions, or incorrect frequency, dose, or route. Statistical analysis was performed using Fisher’s exact test, chi-squares, and generalized linear mix models to examine the relationships between MOEs at admission and patient characteristics, such as ethnicity, number of chronic conditions, or number of medications taken at admission. A total of 115 admission MOEs were identified in 73 hospitalized CMC. The two most common MOE types were wrong dose (41.7%) and omitted medication (33.9%). The median number of medications ordered at admission was 10 (IQR 6-14). Medications most commonly associated with an MOE were cholecalciferol (n=9) and baclofen (n=9). As for patient characteristics, the median age at admission was 5 years ([Interquartile Range [IQR] 1-12). Of the total sample, 96.8% had a complex chronic condition and 72.8% were technology dependent. Children who are Black, require medical technology, or take more than 15 medications during hospitalization were found to have higher MOE rates. Multivariable analysis revealed the highest odds of MOE in children taking baclofen (Odds Ratio [OR] 2.6 [95% Confidence Interval {CI} 1.4-4.7]). MOEs at admission are prevalent among hospitalized CMC. Further study on medication safety in CMC is needed to inform medication reconciliation processes and better prevent patient harm. / 2019-07-03T00:00:00Z

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