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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.
201

The Interim as developmental academic journal

Kokt, D., Lategan, L., Dessels, R. January 2012 (has links)
Published Article / Research has two important objectives: the contribution to scientific discourse and the identification of solutions for the challenges societies, government, business and industry face. Research should be in the public domain. The publication and presentation of research results are important activities academics need to engage with. Through publications and presentations are societies informed of the positive influence and impact research can bring to them. This paper will focus on the importance of publications and how emerging scholars can be assisted to get their research published. A case study is presented of the Interim, an in-house academic journal.
202

TRACKING RECEIVER NOISE BANDWIDTH SELECTION

Pedroza, Moises 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The selection of the Intermediate Frequency (IF) bandwidth filter for a data receiver for processing PCM data is based on using a peak deviation of 0.35 times the bit rate. The optimum IF bandwidth filter is equal to the bit rate. An IF bandwidth filter of 1.5 times the bit rate degrades the data by approximately 0.7 dB. The selection of the IF bandwidth filter for tracking receivers is based on the narrowest “noise bandwidth” that will yield the best system sensitivity. In some cases the noise bandwidth of the tracking receiver is the same as the IF bandwidth of the data receiver because it is the same receiver. If this is the case, the PCM bit rate determines the IF bandwidth and establishes the system sensitivity. With increasing bit rates and increased transmitter stability characteristics, the IF bandwidth filter selection criteria for a tracking receiver must include system sensitivity considerations. The tracking receiver IF bandwidth filter selection criteria should also be based on the narrowest IF bandwidth that will not cause the tracking errors to be masked by high bit rates and alter the pedestal dynamic response. This paper describes a selection criteria for a tracking receiver IF bandwidth filter based on measurements of the tracking error signals versus antenna pedestal dynamic response. Different IF bandwidth filters for low and high bit rates were used.
203

Improving TCP performance over heterogeneous networks : the investigation and design of End to End techniques for improving TCP performance for transmission errors over heterogeneous data networks

Alnuem, M. A. January 2009 (has links)
Transmission Control Protocol (TCP) is considered one of the most important protocols in the Internet. An important mechanism in TCP is the congestion control mechanism which controls TCP sending rate and makes TCP react to congestion signals. Nowadays in heterogeneous networks, TCP may work in networks with some links that have lossy nature (wireless networks for example). TCP treats all packet loss as if they were due to congestion. Consequently, when used in networks that have lossy links, TCP reduces sending rate aggressively when there are transmission (non-congestion) errors in an uncongested network. One solution to the problem is to discriminate between errors; to deal with congestion errors by reducing TCP sending rate and use other actions for transmission errors. In this work we investigate the problem and propose a solution using an end-to-end error discriminator. The error discriminator will improve the current congestion window mechanism in TCP and decide when to cut and how much to cut the congestion window. We have identified three areas where TCP interacts with drops: congestion window update mechanism, retransmission mechanism and timeout mechanism. All of these mechanisms are part of the TCP congestion control mechanism. We propose changes to each of these mechanisms in order to allow TCP to cope with transmission errors. We propose a new TCP congestion window action (CWA) for transmission errors by delaying the window cut decision until TCP receives all duplicate acknowledgments for a given window of data (packets in flight). This will give TCP a clear image about the number of drops from this window. The congestion window size is then reduced only by number of dropped packets. Also, we propose a safety mechanism to prevent this algorithm from causing congestion to the network by using an extra congestion window threshold (tthresh) in order to save the safe area where there are no drops of any kind. The second algorithm is a new retransmission action to deal with multiple drops from the same window. This multiple drops action (MDA) will prevent TCP from falling into consecutive timeout events by resending all dropped packets from the same window. A third algorithm is used to calculate a new back-off policy for TCP retransmission timeout based on the network's available bandwidth. This new retransmission timeout action (RTA) helps relating the length of the timeout event with current network conditions, especially with heavy transmission error rates. The three algorithms have been combined and incorporated into a delay based error discriminator. The improvement of the new algorithm is measured along with the impact on the network in terms of congestion drop rate, end-to-end delay, average queue size and fairness of sharing the bottleneck bandwidth. The results show that the proposed error discriminator along with the new actions toward transmission errors has increased the performance of TCP. At the same time it has reduced the load on the network compared to existing error discriminators. Also, the proposed error discriminator has managed to deliver excellent fairness values for sharing the bottleneck bandwidth. Finally improvements to the basic error discriminator have been proposed by using the multiple drops action (MDA) for both transmission and congestion errors. The results showed improvements in the performance as well as decreases in the congestion loss rates when compared to a similar error discriminator.
204

IC design for reliability

Zhang, Bin 23 October 2009 (has links)
As the feature size of integrated circuits goes down to the nanometer scale, transient and permanent reliability issues are becoming a significant concern for circuit designers. Traditionally, the reliability issues were mostly handled at the device level as a device engineering problem. However, the increasing severity of reliability challenges and higher error rates due to transient upsets favor higher-level design for reliability (DFR). In this work, we develop several methods for DFR at the circuit level. A major source of transient errors is the single event upset (SEU). SEUs are caused by high-energy particles present in the cosmic rays or emitted by radioactive contaminants in the chip packaging materials. When these particles hit a N+/P+ depletion region of an MOS transistor, they may generate a temporary logic fault. Depending on where the MOS transistor is located and what state the circuit is at, an SEU may result in a circuit-level error. We analyze SEUs both in combinational logic and memories (SRAM). For combinational logic circuit, we propose FASER, a Fast Analysis tool of Soft ERror susceptibility for cell-based designs. The efficiency of FASER is achieved through its static and vector-less nature. In order to evaluate the impact of SEU on SRAM, a theory for estimating dynamic noise margins is developed analytically. The results allow predicting the transient error susceptibility of an SRAM cell using a closedform expression. Among the many permanent failure mechanisms that include time-dependent oxide breakdown (TDDB), electro-migration (EM), hot carrier effect (HCE), and negative bias temperature instability (NBTI), NBTI has recently become important. Therefore, the main focus of our work is NBTI. NBTI occurs when the gate of PMOS is negatively biased. The voltage stress across the gate generates interface traps, which degrade the threshold voltage of PMOS. The degraded PMOS may eventually fail to meet timing requirement and cause functional errors. NBTI becomes severe at elevated temperatures. In this dissertation, we propose a NBTI degradation model that takes into account the temperature variation on the chip and gives the accurate estimation of the degraded threshold voltage. In order to account for the degradation of devices, traditional design methods add guard-bands to ensure that the circuit will function properly during its lifetime. However, the worst-case based guard-bands lead to significant penalty in performance. In this dissertation, we propose an effective macromodel-based reliability tracking and management framework, based on a hybrid network of on-chip sensors, consisting of temperature sensors and ring oscillators. The model is concerned specifically with NBTIinduced transistor aging. The key feature of our work, in contrast to the traditional tracking techniques that rely solely on direct measurement of the increase of threshold voltage or circuit delay, is an explicit macromodel which maps operating temperature to circuit degradation (the increase of circuit delay). The macromodel allows for costeffective tracking of reliability using temperature sensors and is also essential for enabling the control loop of the reliability management system. The developed methods improve the over-conservatism of the device-level, worstcase reliability estimation techniques. As the severity of reliability challenges continue to grow with technology scaling, it will become more important for circuit designers/CAD tools to be equipped with the developed methods. / text
205

WORKING PARENTS' CONVERSATIONAL RESPONSES TO THEIR TWO-YEAR-OLD SONS (LINGUISTIC INPUT, LANGUAGE ACQUISITION).

DEMETRAS, MARTHA JO-ANN. January 1986 (has links)
Despite claims by some theorists to the contrary, investigators have shown that information about grammatical errors is available to young children learning language via the conversational responses of their parents. The present study described five categories of responses in the conversations of working mothers and fathers to their normally developing two-year-old sons, and investigated whether any of these responses were differentially related to well-formed vs. ill-formed child utterances. Subjects were six middle-class, monolingual (English) parent-child dyads. Parents worked full-time jobs and the children were enrolled in full-time daycare. Within a two week period, four 20-minute conversational samples were audio and video recorded for each dyad in the subjects' homes during freeplay activities of the subjects' choice. Results indicated that the pattern of responses for these six parents was very similar to that reported for other parent-child dyads. The most frequent type of response for all parents was one that continued the conversation without either repeating or clarifying the child's previous utterance. The least frequent type of response was one that explicitly corrected portions of the child's utterance. Of all responses, repetitions--both clarifying and nonclarifying--appeared to be the type of response most differentially related to well-formed and ill-formed child utterances. Exact repetitions were more likely to follow well-formed utterances, while the remaining repetitions were more likely to follow ill-formed utterances. This pattern of differential responses was similar for all six dyads. Very few differences regarding the style or pattern of interaction were noted for fathers and mothers. Implications were drawn regarding the nature of linguistic input that is available to two-year-old children learning language.
206

Development of a behavioural rating system for scrub nurses' non-technical skills

Mitchell, Lucy January 2011 (has links)
In the first study, a literature review and semi-structured interviews with experienced scrub nurses (n=25) and consultant surgeons (n=9), identified ‘communication’, ‘teamwork’, ‘situation awareness’ and ‘coping with stress’ skills as important skills for scrub practitioners. The second study used focus groups (n=4 groups) of experienced scrub nurses (total n=16 participants) to sort and label the extracted non-technical skill data, from study 1, into skill categories and underlying elements. The focus groups also generated ‘behavioural markers’ describing good and poor performance of those elements. This preliminary taxonomy contained eight categories with 28 underlying elements. An expert panel, comprising two psychologists and a subject matter expert used an iterative process, with reference to the system design guidelines, to refine the taxonomy. The resulting prototype was called the Scrub Practitioners’ List of Intraoperative Non-Technical Skills (SPLINTS) system which had three skill categories – ‘Situation awareness’; ‘Communication and teamwork’; ‘Task management’, each of which had three underlying elements. The third study tested the psychometric properties of the prototype SPLINTS system. Scrub practitioners (n=34) attended a single-day evaluation session where they received training (5 hours) and practice (1 hour) using the SPLINTS system before rating the scrub practitioner’s behaviour seen in standardized surgical video scenarios (n=7) (1 hour). Within-group agreement was acceptable (<i>r</i><sub>wg</sub> &gt;.7) for the three skill categories and for six of the nine elements. Future work will assess the usability of SPLINTS system in the operating theatre environment. This project has provided scrub practitioners with a structured method for training and assessing an important aspect of performance, which could help to reduce adverse events in the operating theatre.
207

Safety measures to reduce medication administration errors in Paediatric Intensive Care Unit

Ameer, Ahmed January 2015 (has links)
Objective: Medicine administration is the last process of the medication cycle. However, errors can happen during this process. Children are at an increased risk from these errors. This has been extensively investigated but evidence is lacking on effective interventions. Therefore, the aim of this research is to propose safety measures to reduce medication administration errors (MAE) in the Paediatric Intensive Care Unit (PICU). Method: The research was carried out over five studies; 1) systematic literature review, 2) national survey of PICU medication error interventions, 3) retrospective analysis of medication error incidents, 4) prospective observation of the administration practice, and 5) survey of PICU healthcare professionals' opinions on MAE contributory factors and safety measures. Results: Hospital MAE in children found in literature accounted for a mean of 50% of all reported medication error reports (n= 12552). It was also identified in a mean of 29% of doses observed (n= 8894). This study found MAE retrospectively in 43% of all medication incidents (n= 412). Additionally, a total of 269 MAEs were observed (32% per dose observation). The characteristics of the interventions used to reduce MAE are diverse but it illustrated that a single approach is not enough. Also for an intervention to be a success it is fundamental to build a safety culture. This is achieved by developing a culture of collaborative learning from errors without assigning blame. Furthermore, MAE contributing factors were found to include; interruptions, inadequate resources, working conditions and no pre-prepared infusions. The following safety measures were proposed to reduce MAE; 1) dose banding, 2) improved lighting conditions, 3) decision support tool with calculation aid, 4) use of pre-prepared infusions, 5) enhance the double-checking process, 6) medicine administration checklist, and 7) an intolerant culture to interruption. Conclusion: This is one of the first comprehensive study of to explore MAE in PICU from different perspectives. The aim and objectives of the research were fulfilled. Future research includes the need to implement the proposed safety measures and evaluate them in practice.
208

GOMDS - GRUMPY OLD MEN DOING SHAKESPEARE; THE COMEDY OF ERRORS AS METAPHOR FOR LIFE, AGING, AND BUILDING COMMUNITY

Pedersen, Elizabeth B 01 January 2017 (has links)
This thesis explores the process of building community over time, through collaboration, to rehearse and produce a portable production of Shakespeare's The Comedy of Errors, looking at the elements of time, trust and age with an ensemble of ten men, all actors over the age of 55. The building of trust over time was vital to the production process and the actors had the time to embody their roles and the language of the play. We look at the questions “why this play,” “why all men?” and “why theatre?” and investigate the physical nature of the play and its violence a la Three Stooges or Punch and Judy. We will look at the themes of aging, discrimination and the search for family and identity, all of which have resonance today, through the lens of play.
209

Comparing the Accuracy of Pyxis Medstation and Pyxis PARx Systems

Krase, Ifat, Sepassi, Marjan January 2010 (has links)
Class of 2010 Abstract / OBJECTIVES: The objective of this study is to compare the number of medication refill errors that occur between the Pyxis Medstation 3500 and the Pyxis PARx automated dispensing systems. The accuracy of refilling Pyxis Medstation 3500 automated dispensing machines by pharmacy technicians at the University Medical Center (UMC) was assessed during six days in July 2009. The accuracy was then reassessed over the course of five days in September 2009, one month after implementation of the new Pyxis PARx barcode technology in August. All medications in both the morning and afternoon Pyxis refill reports generated by the UMC inpatient pharmacy were audited during the chosen days. METHODS: The accuracy of refilling Pyxis Medstation 3500 automated dispensing machines by pharmacy technicians at a 350-bed, tertiary-care, teaching hospital with a total of 50 automated dispensing systems was assessed during five days in July 2009. The accuracy was then reassessed over the course of five days in September 2009, one month after implementation of the new Pyxis PARx barcode technology in August. It was assumed that the following types of medication refill errors would be reduced: 1)Wrong drug, Wrong strength 2) Wrong drug, Right strength 3) Right drug, Wrong strength 4) Filling error/Wrong pocket 5) Overfill of pocket 6) Expired medication 7) Right drug, Wrong form. This study was a prospective evaluation of medication refill errors between an older automated dispensing system (Pyxis Medstation) and a newer system (Pyxis PARx). The addition of PARx barcode technology automates the pick and delivery method in order to enhance security during the medication refill process. When the appropriate drawer is opened, the medication must be scanned using the handheld scanner to make sure the correct medication is being refilled. All medications from each Pyxis refill report on the chosen days were audited during pre and post implementation of the new Pyxis PARx barcode technology. Medications to be audited were identified by collecting data from each automated dispensing system listed on the refill reports for the previous day. Audits were performed on the following day (i.e., Monday’s refill reports was audited on Tuesday) by study investigators. Each completed refill was audited for the above medication errors and a brief description of any errors found was noted. RESULTS: A total of 825 refilled items were audited prior to PARx installation (from dates 7/14/09-7/19/09) and a total of five errors were found. Post PARx installation, 959 items were audited (from dates 9/24/09-9/29/09) and a total of two errors were found. Overall, the types of errors encountered were Right Drug/Wrong Form (1/7, 14.3%), Filling Error/Wrong Pocket (2/7, 28.6%), Overfill (1/7, 14.3%), Expired Medication (2/7, 28.6%) and Right Drug/Wrong Strength (1/7, 14.3%). A Chi-square analysis was done to compare pre and post-PARx implementation errors found. The Chi square value was found to be 1.79 with a p-value of 0.18, meaning that there is an 18% probability that any deviation from expected is due to chance. Thus, per our investigation the installation of PARx did not significantly decrease refill error rates. CONCLUSIONS: In Progress
210

Medication Error Identification Rates of Pharmacy, Medical, and Nursing Students: A Simulation

Queiruga, Caryn, Roush, Rebecca January 2009 (has links)
Class of 2009 Abstract / OBJECTIVES: To assess the ability of pharmacy, medicine, and nursing students to identify prescribing errors METHODS: Pharmacy, medicine, and nursing students from the University of Arizona were asked to participate in this prospective, descriptive study. Pharmacy and medical students in the last didactic year of their program and traditional bachelor of nursing students in the fourth semester of their program were eligible to participate. Subjects were asked to assess a questionnaire containing three sample prescriptions, evaluate if each was correct and indicate the type of error found, if any. The primary outcome measure was the number of correctly identified prescribing errors. The secondary outcome measure was the number of correct types of error found. Error identification rates for each group were calculated. Comparisons in these rates were made between pharmacy, medicine and nursing students. Chi square tests were used to analyze the nominal data gathered from various groups. RESULTS: Pharmacy students were significantly better able to identify errors than medical and nursing students (p<0.001). Pharmacy students were significantly better able to determine the type of error (p<0.001). CONCLUSIONS: Overall, pharmacy students had higher prescribing error identification rates than medical and nursing students. More studies need to be done to determine the most appropriate way to increase prescribing error identification rates.

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