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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.
191

Qualitative study of patterns in attitudes, values and behaviors among fathers of gifted and non-gifted children in selected preschools

Clausing-Lee, Marianne Sue 14 April 1992 (has links)
The purpose of this study was to determine differences in patterns and underlying practices between fathers of gifted and fathers of non-gifted children. The study included 10 fathers of gifted (FG) children and 10 fathers of non-gifted (FN) children. The children were preschoolers, ages 5-6 years old. Giftedness of the children was determined by scoring at or above the 97th percentile on the Weschler Preschool and Primary Scale of Intelligence-Revised. Fathers in both groups were interviewed by the researcher using a 119 item protocol, which covered 16 categories. Data analysis revealed differences in parenting patterns between FG and FN in all 16 categories which included: 1. FG read more to their children and chose a greater variety of reading material, and read a higher proportion of non-fiction. 2. FG were more actively involved doing activities and interacting with their children such as building with blocks and Legos and making up nonsense songs, stories, and riddles. 3. More non-gifted children than gifted children frequently watched television. The non-gifted child watched 11 solid days of television more than the gifted child in the course of a year. Cartoons and comedy programs were the typical pattern chosen by children in the non-gifted household; whereas educational programs chosen jointly by the parent and child was the typical pattern in the gifted household. 4. Both groups of fathers used different strategies for helping the child develop interpersonal problem solving techniques for academic, behavior, and discipline problems. 5. FG mentioned that children were encouraged to fulfill household responsibilities because it was their duty. None of the FN encouraged their children to accomplish their household duties because it was their duty. 6. FG frequently took their children to arts activities an often provided their children access to art reproductions, record players, tape recorders, and CD players that FN. / Graduation date: 1992
192

Age Differences in Distraction Processing

Amer, Tarek 20 November 2012 (has links)
The current study investigates whether younger adults process distraction semantically and how age influences the level of distraction processing. In a first experiment, younger adults’ processing of distraction was examined by comparing implicit and explicit memory for that distraction. Then, in a second experiment, younger and older adults’ semantic processing of distractors was directly tested by examining memory for distractors on a conceptually based category-generation task. Younger adults showed equivalent implicit and explicit distractor memory in the first experiment and no conceptual priming for distractors on the category-generation task of the second experiment. Older adults, on the other hand, showed reliable conceptual priming for distractors, and the effect was significantly correlated with age in that group. The results collectively suggest that older, but not younger, adults engage in elaborate processing of irrelevant information, and that this effect is possibly tied to inhibitory control abilities that tend to decrease with age.
193

Hydrological consequences of two native shrubs in semi-arid Senegal : patterns, processes, concepts and methods

Kizito, Fred 02 December 2005 (has links)
Water availability is a critical limiting element in semi-arid ecosystem productivity and presents particular challenges in Sahelian countries such as Senegal. The landscapes are characterized by the presence of two common semi-arid shrubs (Piliostigma reticulatum and Guiera senegalensis), both of which may be important hydraulic regulators in these water-limited ecosystems. Dry season observations revealed higher moisture levels in soil surrounding the shrub shallower roots relative to bare soil. This observation led us to hypothesize that these shrubs may participate in a natural irrigation phenomenon termed as "hydraulic redistribution" (HR). This dissertation reports on three studies performed to ascertain the existence of and investigate the characteristics of this hypothesized phenomenon. The first study investigated seasonal variability in soil water and shrub root patterns. Soil moisture content declined steadily in the 0.9-1.2 m depth range and increased in the 0.2-0.4 m depth range, which supports the HR hypothesis. The second study quantified plot scale water balance fluxes. Notably, shrub water uptake from the water table served as a crucial contribution to the system water balance. The third study investigated the magnitude and dynamics of HR during the dry season. Crop-shrub associations were evaluated from measurements of soil moisture and potential, root sap flow and plant physiological measurements. This study proved the existence of HR and quantified the HR magnitude (~0.1 mm d⁻¹). For shrubs and annual crops in close association with shrubs, HR clearly provides a mechanism for drought-stress avoidance and maintenance of plant physiological functions. At the landscape scale, the interplay between shrub root morphology and HR may play a vital role in ecosystem function with practical implications for nutrient cycling and water balance in arid ecosystems. / Graduation date: 2006
194

Green food development in China : focus on the east

Wang, Shuang, Xiang, Linjing, Xing, Fei January 2013 (has links)
Purpose/aim The aim of our dissertation is to increase consumers’ buying awareness of green food and promote green food consumption in eastern China. Approach We collect data through a questionnaire and present hypotheses through reading related scientific articles. The data analysis includes description of samples and statistical tests in the form of cross tabulations, chi squares and frequency tables. Findings The questionnaire researches consumers’ income and education levels, ages and price of green food, etc. We find ages and education levels have a significant influence on frequency of buying green food, while income levels and price have no strong influence. Originality/value An original idea is to research the current green food market, and based on it to increase the consumers’ buying awareness and promote green food consumption. Further, the empirical data is collected from different cities in the east where there is a higher demand of green food. The study has value for the debate concerning the group of people who are older and have lower education levels as our great target consumers. The result of income levels and price means consumers are more lay attention to green food quality.
195

The adverse effects of bureaucracy for the hotel industry in China : the investment behaviors changed by different ownerships

Liao, Wang, Zeng, Le, Zhang, Luxin January 2013 (has links)
Purpose/aim The aim is to examine the distribution of hotel ownerships and star-rated levels in different regions. This thesis depends on the analysis of the examination to find out if the change of investment behaviors can decrease or avoid the adverse effects of bureaucracy in the Chinese hotel industry. Design/methodology/approach Data has been collected through the third-party electronic distribution channel. The analysis includes a description of the samples and statistical tests. Findings The analysis showed that there is a connection between hotel ownerships, star-rated levels, and different regions. The adverse effects of bureaucracy in the second-tier cities and third-tier cities are stronger than that in the first-tier cities and tourist cities. The state-owned hotels also can do the enterprise transformation in the tourist cities to avoid or decrease the adverse effects of the bureaucracy. Originality/value The original idea is using the hotel ownerships distribution in different regions to find out the different levels of adverse effects of the bureaucracy in different regions. This thesis should be a meaningful contribution to knowledge development.
196

Infrared Spectroscopy of Graphene in Ultrahigh Magnetic Fields

Booshehri, Layla 06 September 2012 (has links)
Graphene – a two-dimensional honeycomb lattice of sp2-bonded carbon atoms – possesses unusual zero-gap band structure with linear band dispersions, accommodating photon-like, massless electrons that have exhibited a variety of surprising phenomena, primarily in DC transport, in the last several years. In this thesis dissertation, we investigate graphene’s AC or infrared properties in the presence of an ultrahigh magnetic field, produced by a destructive pulsed method. The linear dispersions of graphene lead to unequally spaced Landau levels in a magnetic field, which we probe through cyclotron resonance (CR) spectroscopy in the magnetic quantum limit. Specifically, using magnetic fields up to 170 T and polarized midinfrared radiation with tunable wavelengths from 9.22 to 10.67 μm, we experimentally investigated CR in large-area graphene grown by chemical vapor deposition. Circular-polarization-dependent studies revealed strong p-type doping for as-grown graphene, and the dependence of the CR fields on the radiation wavelength allowed for an accurate determination of the Fermi energy. Upon annealing the sample to remove physisorbed molecules, which shifts the Fermi energy closer to the Dirac point, we made the unusual observation that hole and electron CR emerges in the magnetic quantum limit, even though the sample is still p-type. We theoretically show that this non-intuitive phenomenon is a direct consequence of the unusual Landau level structure of graphene. Namely, if the Fermi energy lies in the n = 0 Landau level, then CR is present for both electron-active and hole-active circular polarizations. Furthermore, if the Fermi level lies in the n = 0 Landau level, the ratio of CR absorption between the electron-active and hole-active peaks allows one to accurately determine the Fermi level and carrier density. Hence, high-field CR studies allow not only for fundamental studies but also for characterization of large-area, low-mobility graphene samples.
197

Implementation of a GIS to Assess the Effects of Water Level Fluctuations on the Wetland Complex at Long Point, Ontario

Hebb, Andrea January 2003 (has links)
The Long Point wetland complex is one of the most significant coastal wetland systems in the Great Lakes, containing a diverse mosaic of wetland vegetation communities that have developed in response to water level fluctuations due to natural climate variability. Natural short-term water level variations are important for promoting wetland productivity and diversity, but long-term water level changes resulting from human-induced climate change can have serious and long-term consequences on the integrity and health of wetlands. The historical response of the wetland to water level fluctuations was quantified and modelled to provide an indication of how the wetland may respond to future projected water level changes - water level fluctuations are used as a surrogate for climate change. A spatiotemporal trend analysis was conducted within a geographic information system (GIS) to determine the effects of water level conditions on wetland vegetation and land cover at the wetland complex at Long Point, Ontario for seven years from 1945 to 1999. The spatiotemporal trend analysis documented changes in the structure and composition of the wetland complex in response to declining and rising water level conditions. During drier periods, there were significant increases in the amount of drier emergent and meadow vegetation, especially within the Inner Bay and northern portion of the outer peninsula. There was less fragmentation and complexity in the wetland as these drier communities expanded forming larger continuous patches of vegetation. During wetter periods, open water increased and there was a predominance of wetter emergent and meadow communities in the wetland. Drier vegetation communities became interspersed with water creating a more fragmented convoluted wetland landscape. The historical response of the wetland vegetation and land cover to water level fluctuations was then simulated with three different wetland models developed in the GIS. A rule-based model, a probability model, and a transition model were developed to assess wetland response to future water level changes. The models were evaluated using simple statistical methods. The transition and rule-based models performed the best and were successful in predicting over 80 % of the wetland vegetation distribution correctly. The probability model was the least successful, predicting only 55 % of the response correctly. The GIS proved successful in documenting wetland response to historical water level fluctuations and providing insight into the potential impacts of future climate change though water level fluctuations on the Long Point coastal wetland complex. The spatiotemporal analysis and wetland modelling advance the role of GIS in wetland management and analysis. They are practical methods within a GIS that can be used to assess the impacts of climate change on wetland systems and to document and model wetland change in other coastal wetlands of the Great Lakes.
198

Implementation of a GIS to Assess the Effects of Water Level Fluctuations on the Wetland Complex at Long Point, Ontario

Hebb, Andrea January 2003 (has links)
The Long Point wetland complex is one of the most significant coastal wetland systems in the Great Lakes, containing a diverse mosaic of wetland vegetation communities that have developed in response to water level fluctuations due to natural climate variability. Natural short-term water level variations are important for promoting wetland productivity and diversity, but long-term water level changes resulting from human-induced climate change can have serious and long-term consequences on the integrity and health of wetlands. The historical response of the wetland to water level fluctuations was quantified and modelled to provide an indication of how the wetland may respond to future projected water level changes - water level fluctuations are used as a surrogate for climate change. A spatiotemporal trend analysis was conducted within a geographic information system (GIS) to determine the effects of water level conditions on wetland vegetation and land cover at the wetland complex at Long Point, Ontario for seven years from 1945 to 1999. The spatiotemporal trend analysis documented changes in the structure and composition of the wetland complex in response to declining and rising water level conditions. During drier periods, there were significant increases in the amount of drier emergent and meadow vegetation, especially within the Inner Bay and northern portion of the outer peninsula. There was less fragmentation and complexity in the wetland as these drier communities expanded forming larger continuous patches of vegetation. During wetter periods, open water increased and there was a predominance of wetter emergent and meadow communities in the wetland. Drier vegetation communities became interspersed with water creating a more fragmented convoluted wetland landscape. The historical response of the wetland vegetation and land cover to water level fluctuations was then simulated with three different wetland models developed in the GIS. A rule-based model, a probability model, and a transition model were developed to assess wetland response to future water level changes. The models were evaluated using simple statistical methods. The transition and rule-based models performed the best and were successful in predicting over 80 % of the wetland vegetation distribution correctly. The probability model was the least successful, predicting only 55 % of the response correctly. The GIS proved successful in documenting wetland response to historical water level fluctuations and providing insight into the potential impacts of future climate change though water level fluctuations on the Long Point coastal wetland complex. The spatiotemporal analysis and wetland modelling advance the role of GIS in wetland management and analysis. They are practical methods within a GIS that can be used to assess the impacts of climate change on wetland systems and to document and model wetland change in other coastal wetlands of the Great Lakes.
199

none

Lai, Po-chih 18 June 2010 (has links)
Abstract SMT process is the most critical process to influence products quality in electronic assembly house process. Especially,the solder paste printing control is the key process to determine the yield rate of SMT quality. To own the capability to control quality of solder paste printing is the important thing what assembly house have to face it¡C For the purpose of gaining good SMT yield & solder paste printing stability ,the study use six sigma management technique & procedure (DMAIC--Define¡BMeasure¡BAnalyze¡BImprove & Control) make the main factors of solder paste printing¡Aincluding Printing speed¡BScraper pressure¡BStencil clean frequency¡Ato be the experiment factors of DOE(Design of Experiment)¡CThe DOE minimize the experiment number of times and provide a way of 2 levels factorial design combine RSM(Response Surface Methodology) experiment to get the optimization combination of factors¡¦ levels. Then evaluate how the optimization combination of factor levels to influence the quality of SMT¡C The study final found that there are a surprised & satisfied result on SMT yield improvement caused by optimization combination of factors¡¦ levels which 2 levels factorial design combine RSM experiment generated. It can provide the procedure & methodology for SMT assembly house reference to improve yield rate .
200

Routing with Safety Vectors in the Hypercube

Chung-Rung, Shih 20 August 2001 (has links)
Reliable communication in the hypercube with the safety vectors is discussed in this thesis. In the hypercube, the safety levels and the safety vectors, used to guide fault-tolerant routing, is a kind of limited global information based methods. The transmission cost of the safety vectors is O(n2) for each node. For increasing the probability of optimal routing, we attempt to increase the transmission cost for obtaining more information. We propose two methods with O(n3) transmission cost in each node, the enhanced safety vector and the spanning safety vector, to achieve the goal. We also propose the probabilistic safety vector which provides the probability of optimal routing for each node. Finally, our experiments show that the routing with the enhanced safety vector is more reliable than the safety vectors and the extended safety vectors, which were propose the probabilistic safety vector.

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