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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.
221

Three essays on the relationship between migration and occupational licensing /

Tenn, Steven Aaron. January 2001 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Economics, August 2001. / Includes bibliographical references. Also available on the Internet.
222

The road less traveled : forms of mobility in The motorcycle diaries

Mills, Brian Scott 19 July 2012 (has links)
The Road Less Traveled is about engaging film from a geographic perspective, specifically analyzing the underlying structures, cultural contexts and forces affecting the movements of the two main protagonists of the film The Motorcycle Diaries. The focus at the individual scale aims to reveal not just how and where, but why people chose to move where they do. The paper is divided into five main chapters: mobility as resistance, mobility as structured process in the form of motility and moorings, forced mobility as distinctive from chosen mobility, mobility as discovery and a final body chapter that demonstrates examples of all these types of mobility. These sections will mainly flow as neoformal, mostly chronologic descriptions of the film text, but will also occasionally reference the written text of the two diaries on which the movie is based. While the main character of the film is Che Guevara, no attention will be dedicated to his revolutionary life outside of the time frame encompassed by the film. / text
223

Stability analysis for SRAM cells with TSV induced stress in 3D ICs

Zhang, Wen, 1990- 30 October 2012 (has links)
Three-dimensional integrated circuits (3D-IC) have emerged as promising candidates to overcome the interconnect bottlenecks of nanometer scale designs while also helping to reduce wire delay and increase memory throughput. While this technology offers many potential advantages, it also produces large thermal mismatch stress in 3D-IC structures employing Through-Silicon-Via (TSV). The stress distribution in silicon and interconnect is affected by the via diameter and layout geometry. TSV-induced stress effects on electron/hole mobility and device performance will be studied for the widely used 6-transistor (6T) SRAM cell. Simulation results in this study show that static noise margin (SNM), Read Margin (RM) and write margin (WM) tend to increase with decreasing electron mobility or increasing hole mobility. Considering TSV-induced stress, we propose that for practical layouts of TSV-based 3D-IC, p-type substrates should be placed further away from TSVs or closer to the smaller TSVs if multiple TSVs exist. / text
224

The postsecondary resource trinity model : exploring the interaction between socioeconomic, academic, and institutional resources

Giani, Matthew Shankar 09 February 2015 (has links)
It is frequently stated that higher education is our nation’s greatest vehicle for social mobility. But despite the dramatic expansion of the postsecondary system since the 1940s, social mobility rates have remained stagnant and significant socioeconomic disparities in college attainment have persisted. Three explanations of this phenomenon appear most prominently in the literature. The first is that low-SES students are significantly less likely to be academically prepared for college. The second is that, even when college-ready, low-SES students are more likely to attend less selective or lower quality postsecondary institutions, decreasing their odds of attainment. The third is that socioeconomic background may exert an independent effect on the likelihood of postsecondary success, independent of background ability and institutional quality. Although each explanation is supported empirically, thus far limited attempts have been made to determine how these three factors interact across educational transitions. The purpose of this study is to estimate the relative impact of SES across transitions in students’ college-to-career pathways and explore how socioeconomic disparities in rates of student outcomes vary by student ability, institutional selectivity, and the combination of the two. Sequential logit modeling, a methodological staple in research on the effects of socioeconomic background on educational progression, is used to estimate the relative effect of SES on seven postsecondary transitions, from college application through graduate school attainment. The labor market outcomes of college graduates are also analyzed to determine whether family upbringing continues to influence students even after completing college. For both the postsecondary and labor market analyses, separate models are fit for different ability groups and institutional selectivity levels to investigate how these factors impact the magnitude of socioeconomic disparities in transitions. The results of this study suggest the need for a new conceptualization of this phenomenon, which is termed the Postsecondary Resource Trinity model. This model highlights the complex interaction between socioeconomic, academic, and institutional resources and suggests the need for a re-examination of the traditional perspective that the impact of SES declines steadily for all students as they progress through postsecondary. Implications of the model for policy, practice, and future research are discussed. / text
225

No longer salaried professionals : a case study of educated Taiwanese migrant women in the U.S.

Chien, Pei Yin 04 January 2011 (has links)
Most migration literature shows that skilled professionals have upward social mobility. But all of this literature is mostly about men. Plus, it focuses on individuals who are already on the job market. How immigrant women fare in the labor market and what about women who are still not incorporated into the high wage sector are seldom discussed. This research shows that professional migrant women face downward mobility. With limited job opportunities, as a result of having both visible barriers (legal constraints) and invisible barriers (culture, language, social network, credential and so on), the high-achieving migrant women become more "traditional" in the United States. Their roles as wives, mothers, part-time workers, volunteers take on a bigger aspect of their lives than their professional lives. In Taiwan they were far more active in the sphere of the economy, earning an independent income, but in the U.S. that is reversed. The experiences of these educated migrant women demonstrate that immigration does not uniformly empower migrants nor does it imply upward economic and social mobility. The study hopes to be the basis for further investigations of upper middle class migrant women in other areas in the America, and hopes to be the basis for future development to understand migrants’ downwards mobility in general. / text
226

Ποιότητα υπηρεσιών, κινητικότητα και ενεργειακή κατανάλωση σε ασύρματα τοπικά δίκτυα (WiFi)

Μανωλόπουλος, Τιμολέων 26 August 2009 (has links)
Αντικείμενο της παρούσας διπλωματικής εργασίας είναι η μελέτη της κινητικότητας, της ποιότητας των υπηρεσιών (QoS) και η ενεργειακή κατανάλωση σε ασύρματα τοπικά δίκτυα, όταν αυτά διασυνεργάζονται με άλλης κατηγορίας δίκτυα ασύρματων επικοινωνιών. Στο σύγχρονο αυτό ετερογενών τεχνολογιών περιβάλλον, προτείνουμε ένα σύστημα διαχείρισης της κινητικότητας ελεγχόμενο από τον κινητό τερματικό κόμβο και έναν αλγόριθμο επιλογής πρόσβασης με σκοπό την διαρκώς βέλτιστη ανάθεση των υπηρεσιών, έτσι ώστε να ικανοποιείται παντού και πάντα η συνθήκη της βέλτιστης σύνδεσης. / The objective of this diploma thesis is the study of mobility management, quality of service and energy consumption of Wireless Local Access Networks (WLAN) when they interact with other wireless networks. In this heterogeneous wireless enviroment we propose a management system of mobility controlled by the terminal node and an algorithm of access interface selection, which satisfies the requirements of the concept ABC (Always Best Connected).
227

Modeling of performance behavior in gas condensate reservoirs using a variable mobility concept

Wilson, Benton Wade 30 September 2004 (has links)
The proposed work provides a concept for predicting well performance behavior in a gas condensate reservoir using an empirical model for gas mobility. The proposed model predicts the behavior of the gas permeability (or mobility) function in the reservoir as condensate evolves and the gas permeability is reduced in the near-well region due to the "condensate bank". The proposed model is based on observations of simulated reservoir performance and predicts the behavior of the gas permeability over time and radial distance. This model is given by: The proposed concept has potential applications in the development of a pressure-time-radius solution for gas condensate reservoirs experiencing this type of mobility behavior. We recognize that the proposed concept (i.e., a radially-varying gas permeability) is oversimplified, in particular, it ignores the diffusive effects of the condensate (i.e., the viscosity-compressibility behavior). However, we have effectively validated the proposed model using literature results derived from numerical simulation. This new solution is presented graphically in the form of "type curves." We propose that the "time" form of this solution be used for applications in well test analysis. Previous developments used for the analysis of well test data from gas condensate reservoirs consider the radial composite reservoir model, which utilizes a "step change" in permeability at some radial distance away from the wellbore. Using our proposed solution we can visualize the effect of the varying gas permeability in time and radius (a suite of (dimensionless) radius and time format plots are provided). In short, we can visualize the evolution of the condensate zone as it evolves in time and radial distance. A limitation is the simplified form of the kg profile as a function of radius and time - as well as the dependence/appropriateness of the α-parameter. While we suspect that the α-parameter represents the influence of both fluid and rock properties, we do not examine how such properties can be used to calculate the α-parameter.
228

Some aspects of residential mobility in urban social space. / Residential mobility in urban social space.

Gilmour, Gillain. January 1969 (has links)
No description available.
229

The effect of limited hip mobility on the lumbar spine in a young adult population

Moreside, Janice Marie 24 August 2010 (has links)
Limited hip mobility is known to affect the lumbar spine. Much of the previous research has utilized a participant population whose hip mobility is compromised due to arthritic or neurological dysfunctions. Such aetiologies may confound the outcomes, as their effects may not be limited to the hip. The purpose of this thesis was to recruit a healthy young adult population with limited hip mobility to further investigate its effect on the lumbar spine, as well as the role of exercise intervention. Several cascading studies were conducted that were unified around a central theme of links between hip and spine function: Study # 1 investigated the normal distribution of passive hip extension and rotation in a group of 77 males (age 19-30). Data was collected using an infra-red motion capture system and compared to goniometric measurements. The resulting angles represent the 5th – 95th percentiles, including the averages and standard deviations. Study # 2 compared movement patterns between groups of males with limited and excessive hip mobility. Participants were required to perform simple functional activities (lunging, twisting, walking, etc) as well as use the elliptical trainer. Resulting hip and spine angles demonstrated that the men with limited hip mobility stood with a more anteriorly tilted pelvis, and assumed a posture with more lumbar and hip flexion on the elliptical trainer, compared to those with greater mobility. This, in turn, resulted in a greater lumbar compression load due to increased back muscle activity. Study #3 involved recruitment of 24 young adult males with limited hip mobility. Their movement patterns were assessed (as in study #2), then they were assigned to one of four intervention groups: hip stretching, spine stabilizing, hip stretching combined with spine stabilization, and control. Participants in the 3 exercise groups attended supervised exercise sessions once/week for 6 weeks, but were expected to exercise a minimum of 4 times/week on their own. At the end of the 6 weeks, intake parameters were re-assessed, and movement pattern assessment repeated. Despite significant increases in available hip flexibility and/or large increases in trunk muscle endurance and trunk motor control, there were few indications that participants were any more adept at decreasing lumbar motion, or utilizing their newfound hip flexibility during functional activities. Study #4 compared those in the 10th and 90th percentiles of available hip rotation, using a frictionless apparatus to investigate passive stiffness properties of the hip. Participants adopted a posture of upright standing, with one leg supported on a turntable apparatus, and upper body and pelvis secured. A an applied rotational moment resulted in passive hip internal and external rotation. Outcomes demonstrate that those with limited hip mobility stand with the leg more externally rotated and require a larger moment to initiate motion. Passive stiffness curves indicate greater stiffness properties in those with limited hip mobility, and more resistance to an external rotation moment than internal rotation. Study #5 investigated passive hip stiffness in the sagittal plane, comparing those with limited and excessive hip extension. Using a frictionless jig, with the participants lying on their left side, the left hip was pulled into extension with knee position varying. Those with limited hip mobility demonstrated increased passive stiffness compared to the more mobile group, and stiffness was greater when the knee was in extension. The group with limited mobility also showed a trend of increased back extension compared to the more mobile group, when the hip and lumbar spine were both free to react to the applied extension moment. Study #6 summarizes the spine/hip kinematics and muscle activation levels produced when using the elliptical trainer, as well as lumbar compressive and shear forces. It differs significantly from walking in that it produces more lumbar motion in flexion/extension and lumbar twist, but less lateral bend. Participants also tended to adopt a greater mean lumbar flexion angle on the elliptical, which in turn resulted in greater muscle activity in the back extensors. Varying hand position, velocity and stride length were all found to significantly affect the amount of lumbar motion. Highly phasic muscle activity is seen, with the gluteal muscles and internal obliques demonstrating the greatest activation levels.
230

Aboriginal Peoples' Mobility and Health in Urban Canada: Traversing Ideological and Geographical Boundaries

Snyder, Marcie Rachel 14 January 2014 (has links)
In recent decades, the Aboriginal population in Canada has become increasingly urbanized. Urbanization has been accompanied by high rates of mobility between reserve/rural and urban areas, as well as within cities. While research has documented Aboriginal peoples’ mobility rates, little attention has been given to mobility experiences, and an understanding of the socio-political and historic context in which mobility is set remains underdeveloped. Furthermore, little is known about the impact of mobility on movers’ holistic health (i.e., physical, mental, emotional, spiritual), and while research has suggested that mobility may impact access to urban social and health services, little is known in this area. The objectives of this dissertation are therefore to examine: the broader motivations that shape mobility, the link between mobility and health as well as service use, and to produce a more comprehensive understanding of the relationship between service providers and movers. These objectives are addressed using multiple methods. Quantitative analyses of the 2006 Aboriginal Peoples Survey identified mobility as a significant correlate of conventional (physician/nurse) and traditional (traditional healer) health care use. In order to explore nuanced links between mobility, health, and urban service delivery, a collaborative, community-based research relationship was established with an urban Aboriginal-led organization and 46 in-depth, semi-structured interviews were conducted with Aboriginal service providers, non-Aboriginal service providers, and urban Aboriginal movers in the city of Winnipeg, Manitoba, Canada. These research findings reveal the importance of service delivery that actively supports urban Aboriginal movers, and demonstrates the relationship between mobility and holistic health as well as service access in urban areas. Furthermore, current scales of service delivery are found to be insufficient for meeting the needs of mobile urban Aboriginal populations. Despite these findings, urban Aboriginal movers are maintaining important networks of support between their points of origin and destination, and are creating new spaces of engagement within cities.

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