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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.
71

A spectroscopic survey of the supercluster RCS2319+00 /

Faloon, Ashley J., 1983- January 2008 (has links)
No description available.
72

A Sociophonetic Study of the Northern Cities Shift in Southwest Michigan

Daniels, Sara 01 May 2014 (has links) (PDF)
This study was designed to measure the perception of Southwest Michigan residents' perception of the Northern Cities Shift, and compare it to the perceptions of Southeast Michigan residents. Participants, recruited from the Grand Rapids and Kalamazoo areas, were asked to complete a dialect boundary map of the United States in order to discern perceptions of American English dialects and accents and determine the dialect or accent that they most associate with the state of Michigan. Participants were also asked to listen to and judge the personality traits of seven different North American speakers. The results of this study indicate that Southwest Michigan residents may subconsciously be able to detect the NCS in speech, though they were mostly unable to correctly identify the NCS as a characteristic of Michigan speech. Further research with a larger pool of participants could provide more accurate measurements as to the perception of Michigan residents towards the Northern Cities Shift.
73

Psychological Symptom Patterns in Night Shift Workers

Kowalski, Justin 01 May 2015 (has links)
The negative physical effects of night shift work are well understood. Research into psychological problems associated with night shift work, however, is sparse. The purpose of this study was to evaluate the difference in psychological symptom patterns between day and night shift workers. Data were obtained on 121 undergraduate volunteers. The sample consisted of 39 male and 82 female volunteers between the ages of 18 and 58 years. All participants were organized into two shift types: Day and Night. Day (n = 65) was classified as working hours primarily in the daytime (7 AM – 5PM). Night (n = 56) was classified as working hours primarily in the nighttime (6 PM – 6 AM). A two-way between-subjects MANOVA was used to assess the influence of gender and shift on the nine SCL-90-R subscale T-scores. The gender main effect was not significant, F(9, 109) = .668, p = .736. No significant difference in SCL-90-R subscale scores as a function of shift was observed, F(9, 109) = 1.141, p = .34. The gender x shift interaction was not significant, F(9, 109) = 1.308, p = .241. Results showed no significant difference between day and night shift worker distress levels. Further research into this topic is recommended.
74

Relationship of Shift Work Schedules and Job Satisfaction of Female Nurses

Antrim, Maurie L. 01 January 1986 (has links) (PDF)
The purpose of the study was to identify variables which are related to job satisfaction, focusing on shift schedules and their impact on life activities outside the work setting. The sample consisted of 72 female nurses. The subjects received questionnaires which contained questions relating to biographical information (age, gender, marital status, number and ages of children, length of time on the job), work schedule information (shift worked, number of weekends and holidays worked), and satisfaction information (shift schedule satisfaction, satisfaction with amount of weekend work, satisfaction with days worked/days off schedule, and satisfaction with amount of time for family, friends, and leisure). Correlation and multiple regression analyses were computed on all respondents and separately for those without children and for those with children. Only shift schedule satisfaction and amount of weekend work were found to be significantly related to job satisfaction for all respondents. Shift assignment was unrelated to job satisfaction. The other five satisfaction variables (weekend work, days worked/days off schedule, family, friend, and leisure time) were significantly correlated with job satisfaction for all respondents and for those without children. Multiple regression analyses showed that days worked/days off schedule satisfaction accounted for the most variance in job satisfaction scores.
75

Minimal Presentations of Sofic Shifts and Properties of Periodic-Finite-Type Shifts

Manada, Akiko 12 August 2009 (has links)
Constrained codes have been used in data storage systems, such as magnetic tapes, CD’s and DVD’s, in order to reduce the likelihood of errors by predictable noise. The study of constrained codes is based on the study of sofic shifts, which are sets of bi-infinite sequences that can be presented using labeled directed graphs called presentations. In this thesis, we will primarily focus on two classes of sofic shifts, namely shifts of finite type (SFT’s) and periodic-finite-type shifts (PFT’s), and examine their properties. We first consider Shannon covers of sofic shifts. A Shannon cover of a sofic shift is a deterministic presentation with the smallest number of vertices among all deterministic presentations of the shift. Indeed, a Shannon cover is used as a canonical presentation of a sofic shift, and furthermore, it is used when computing the capacity of the shift or when constructing a finite-state encoder. We follow an algorithm by Crochemore, Mignosi and Restivo which constructs a deterministic presentation of an SFT and we see how to derive a Shannon cover from the presentation under their algorithm. Furthermore, as a method to determine whether a given deterministic presentation is a Shannon cover of a sofic shift, we will provide, based on research by Jonoska, a sufficient condition for a given presentation to have the smallest number of vertices among all presentations of the shift. We then move our focus towards PFT’s, and investigate new properties of PFT’s from various perspectives. We define three types of periods that can be associated with a PFT and do pairwise comparisons between them. Also, we consider the zeta function of a PFT, which is a generating function for the number of periodic sequences in the PFT, and present a simple formula to compute the zeta function of a PFT. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2009-08-08 14:08:36.876
76

Hearing protection in mines : evaluating the Noise Clipper® custom made hearing protection device

Kock, Johan Frederick Willem 14 June 2013 (has links)
Noise induced hearing loss has been extensively researched and commented on, yet it remains prevalent among industrial workers. The real-world attenuation properties of the Noise Clipper® custom-made hearing protection device and the comfort levels it afford are unknown. Furthermore, research in hearing conservation is seldom focused on the critical/biological thresholds for temporary threshold shift. Field studies on hearing protection devices have demonstrated that laboratory derived measures bear little relation to attenuation achieved in workers. Research has consistently demonstrated that noise reduction ratings that are derived from the laboratory real-ear-at-threshold method do not accurately represent the attenuation of noise that these devices actually provide and the matter remains unclear. Too many important variables are neglected in current real-ear-atthreshold evaluation protocols. This study used an alternative method, the microphone-inreal- ear approach where a dual-element microphone probe was inserted into the Noise Clipper® to measure noise reduction by recording the difference in noise levels outside and behind the device. The sub aims of the study were to record ambient noise levels and frequency spectra; to determine the attenuation characteristics; and to compare the attenuation thresholds to biological thresholds for temporary threshold shift. Using this protocol, measurements were made on 20 subjects in real world situations in order to match the attenuation characteristics of the Noise Clipper® to the actual noise exposure. The microphone-in-real-ear derived attenuation thresholds were compared to the real-earat- threshold values provided by the manufacturer of the Noise Clipper®. Additional subaims were to determine the comfort levels of the Noise Clipper® and record the selfreported wearing time of the device. Wearing comfort was evaluated using a bipolar rating scale. The researcher interviewed 240 mine workers at a platinum mine. Several comfort related sub-scales were used to quantify reported comfort levels. Simultaneously, usage time of the device was self-reported by each worker. Results of the microphone-in-real-ear measurements indicated that ambient noise levels fluctuated from day to day. The attenuation results indicated that most of the measurements suggested protection against noise induced hearing loss through the use of the Noise Clipper®. It was found that the REAT results over estimated the attenuation ability of the Noise Clipper® when compared to the results of the F-MIRE measurements. Eighty seven percent of the measurements indicated protection from thresholds below the biological threshold for temporary threshold shift. Seventy five percent of the workers indicated that the Noise Clipper® was comfortable to wear and 79% indicated that they used it for a full eight hour shift. The results provide an opportunity to assess the use of a protection device and its effectiveness among mineworkers combined with information regarding noise exposure levels. The findings highlight the importance of evaluating variability in terms of individual-specific protection. / Dissertation (MCommunication Pathology)--University of Pretoria, 2013. / Speech-Language Pathology and Audiology / unrestricted
77

A Reflection Type Phase Shifter for iNET Phase Array Antenna Applications

Shrestha, Bikram 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / In this article we present results from modeling and simulation of a L-band reflection type phase shifter (RTPS) that provides continuous phase shift of 0° to 360°. The RTPS circuit uses a 90º hybrid coupler and two reflective load networks consisting of varactor diodes and inductors. Proper design of 90° hybrid coupler is critical in realizing maximum phase shift. The RTPS circuit implemented on a Rogers Duroid substrate is large in size. We discuss methods to reduce the size of L-band RTPS.
78

A millennial mindset: how modal shift affects the transportation choices of university students

Weber, Jessica January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional & Community Planning / Brent Chamberlain / Growing urban populations and the increasing prevalence of the millennial generation are profoundly changing personal travel behaviors and patterns. As a result, cities, planners, and developers must understand and act upon the shifting preferences and expectations of these public transit users in order to align costly public transit services with user needs in efficient ways. While public transit systems are becoming an increasingly vital part of urban life, few jurisdictions have considered the need to tailor these systems to millennials – those most likely to incorporate public transit into their daily lives. This paper examines the travel behaviors of University Students engaged in a forced travel intervention caused by a sudden relocation of their work site. The change in work location encouraged the use of a free public transit system as means of commuting. Longitudinal survey results, taken pre and post-intervention, indicate statistical differences between transit preferences and actual habits related to transit use and other modes of travel. Survey findings suggest that there is a statistically significant difference between the stated willingness and actual travel behaviors of public transit users and of drivers, and that modal shifts can assist in overcoming the attitude/behavior split related to personal travel among millennials.
79

Search for rapidly star-forming galaxies at high redshift.

Elston, Richard Joseph. January 1988 (has links)
We have conducted three surveys to try and locate distant star forming galaxies. The most general survey used deep 2μ images with optical CCD photometry to locate objects with peculiar SEDs. Using the IR data we should be able to locate rapidly star forming galaxies to z = 25. With a 3σ detection limit of 18.5 at K we have found no objects with z > 5 but we have found several blue objects at z < 4 in 16min² of sky. This suggests tha there is no extremely luminous early phase of galaxy formation. We have found several blue objects at z < 4 in 10min² of sky. Of particular interest is an object which has a flat SED from V to K but shows a strong spectral break between B and V and a weaker break at 5800Å. We suggest these may be Lyman limit and Lyman α forest absorption at z-3.8 in a galaxy forming ≈400M(⊙) year⁻¹ of stars. A large sample of galaxies (100 objects) selected to have similar properties (R – I < .5, B – R > 1) has also been found. From this sample it appears this possible high redshift star forming phase only contributes 1/10 of the metal present in disks or spheroids. We have also found 30 Lyman α emission line companions to 12 z = 3 quasars. These objects have Lyman α equivalent widths (50Å) and luminosities (V = 24) consistent with galaxies forming ≈100M(⊙) year⁻¹ of stars. Also, 2 of the quasars have 8 companions and may be in cluster environments. A final survey analyzed optical to IR SEDs of luminous blue radio galaxies at z > 1. In these objects we find SEDs indicative of star formation rates between 10 and 100M(⊙) year⁻¹ but interpretation is difficult due to the AGN component of the sources. While these data seem to suggest a significant star forming phase taking place in galaxies at z ≈ 3-4, interpreting this result is difficult since we cannot determine if we are observing disk or spheroidal populations. In the case of the quasar companions and the radio galaxies, consideration of their dense environments and current epoch morphology suggest that these may be spheroids but these galaxies may not be typical of galaxies in general.
80

Substituent chemical shifts in N.M.R

Fisher, J. January 1986 (has links)
No description available.

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