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Spatial and temporal variability of organic carbon metabolism in Kaoping Coastal Sea and northern South China SeaWang, Yu-chieh 04 August 2005 (has links)
This study aims to understand the influence of hydrochemical and nutrient dynamics on the metabolism of organic carbon, and to explore the relationship between the metabolism of organic carbon and air-sea fluxes of CO2 in the Kaoping coastal zone and the northern South China Sea (NSCS).
Distributions of nutrients in the Kaoping Canyon increased generally with the increase of freshwater input from the Kaoping River that discharged the highest rate during the summer season. In the northern SCS, the enhanced nutrient distributions were caused by freshwater input or upwelling in coastal and shelf zones, and by vertical mixing in the central basin in winter. During the study periods, the integrated gross production (IGP) ranged from 1389 to 8918 mgC m-2d-1 in the Kaoping Canyon, and from 851 to 5032 mgC m-2d-1 in the NSCS. The integrated dark community respiration (IDCR) ranged from 919 to 5848 mgC m-2d-1 in the Kaoping Canyon, and from 435 to 10707 mgC m-2d-1 in the NSCS. The higher IGP was found in summer than in winter for both study areas, primarily due to greater inputs of freshwater from the Kaoping River and/or from the Pearl River. The deeper euphotic depth may be also
responsible for higher IGP in the central basin during the summer season. Positive correlations are significant between GP (DCR) and temperature, PAR and nutrients, and negative correlations are also significant between GP (DCR) and salinity, showing the significant impacts of freshwater inputs and climatic changes on GP (DCR). However, GP was determined largely by DCR, and DCR was attributed mainly to BR (bacteria respiration) for both the Kaoping Canyon (ave., 78%) and the NSCS (ave., 65%). In addition, the ratio of IBR/IDCR ranged from 48 to 88% for the Kaoping Canyon and from 58 to 88% for the NSCS.
The ratio of IGP/IDCR is an indicator of net ecosystem production, with >1 for the autotrophic system and <1 for the heterotrophic system. The ratio was greater than 1.0 for most stations during summer but was <1.0 away from the nearshore station during winter in the Kaoping Canyon. The ratio was <1.0 for all but stations near the Pearl estuary (H and H1 stations) during both summer and winter in the NSCS, indicating a year-round heterotrophic around the slope and basin of NSCS. However, this ratio was higher in winter than in summer in the NSCS, possibly resulted from higher GP in winter than in summer.
The IGP/IDCR may not be the sole factor in determining the air-sea fluxes of CO2. The physical forcing such as temperature and wind velocity may be also important in determining the source or sink of CO2 in the study areas.
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noneTeng, Che-Wei 14 August 2002 (has links)
none
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Quantum Systems in Bernoulli PotentialsBishop, Michael Anthony January 2013 (has links)
Quantum mechanics is a theory developed to explain both particle and wave-like properties of small matter such as light and electrons. The consequences of the theory can be counter-intuitive but lead to mathematical and physical theory rich in fascinating phenomena and challenging questions. This dissertation investigates the nature of quantum systems in Bernoulli distributed random potentials for systems on the one dimensional lattice {0, 1, ..., L, L+1} ⊂ Z in the large system limit L → ∞. For single particle systems, the behavior of the low energy states is shown to be approximated by systems where positive potential is replaced by infinite potential. The approximate shape of these states is described, the asymptotics of their eigenvalues are calculated in the large system limit L → ∞, and a Lifschitz tail estimate on the sparsity of low energy states is proven. For interacting multi-particle systems, a Lieb-Liniger model with Bernoulli distributed potential is studied in the Gross-Pitaevskii approximation. First, to investigate localization in these settings, a general inequality is proven to bound from below the support of the mean-field. The bound depends on the per particle energy, number of particles, and interaction strength. Then, the ground state for the one-dimensional lattice with Bernoulli potential is studied in the large system limit. Specifically, the case where the product of interaction strength and particle density is near zero is considered to investigate whether localization can be recovered.
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Interrelationships and assessment criteria of gross motor skill development and obesity of preschool children in Potchefstroom / Dorita du ToitDu Toit, Dorita January 2001 (has links)
In the holistic development of the young child, optimal gross motor development has an
important influence on optimal physical, perceptual, cognitive, language, affective-social
and normative (behavioural) development (Kapp, 1991; Gallahue & Ozmun, 1998), and
is therefore considered to be essential in the preschool years. The goal of this dissertation
was to present the results of much-needed recent research on gross motor development of
a group of children living in an urban area in South Africa, by 1) determining the current
levels of gross motor development, 2) assessing the prevalence of and the influence of
overweight and obesity on gross motor development, 3) establishing the relationship
between overweight and obesity, gross motor development and gender, 4) determining
the relationship between quantitative and qualitative assessment results of the one leg
balance, and 5) investigating the occurrence of gender differences in gross motor
development, in a group of 3-6 year old children living in Potchefstroom. These aims
were addressed by structuring the dissertation in eight chapters, Chapter 1 constituting
the introduction and statement of the problem, Chapter 2 a review of relevant literature,
Chapters 3 to 7 constituting 5 research articles addressing the specific aims of the study,
and Chapter 8 including the summary, conclusions and recommendations.
For each of the 5 research articles, the participants were 3-6 year old children (N = 514)
who lived in Potchefstroom and had been enrolled in the movement development
program (MDP) presented by movement developmentalists of the Potchefstroom
University for Christian Higher Education (P.U. for C.H.E.). Descriptive statistics
(Chapter 3-7), practical significance based on effect sizes (Chapter 4 and 5), 2 way
frequency tables and Pearson Chi-square as well as the Phi for two-way tables (Chapter
6), and t-values, degrees of difference and p-values (Chapter 7) were used. The current levels of gross motor development of preschool children in Potchefstroom
(Chapter 3) were determined by testing a total of 462 3-6 year old children (215 males
and 247 females) on 8 gross motor tasks, and comparing the results to norms and criteria
as found in the literature. The 3, 4 and 5 year olds compared favourably to their
counterparts in all the tests except for balance walk and catching, standing long jump in
the 4 year olds and throwing in the 5 year old group. The 6 year old group scored lower
than the norms and criteria in all the tests except for standing long jump, indicating
alarming implications for school readiness.
Chapter 4 and Chapter 5 examined the prevalence of and the differences in the
quantitative and qualitative execution of four gross motor tasks (standing long jump,
hopping, one leg balance and catching) between groups of overweight and obese (0) and
nonobese (NO) boys, and girls, respectively. In the male study, 17 0-participants and 49
NO-participants were compared, while 13 0-participants and 54 NO-participants were
used in the female study. Differences of practical significance (medium or large effects)
in favour of nonobese groups were found in all the quantitative and qualitative tests
among the male participants, while similar differences were found in only the
quantitative tests for the one leg balance and all the qualitative tests among the female
participants. A prevalence of overweight and obesity of 16.35% was found among the
boys and 11.81% among the girls. The results indicated that 0-children of the ages 3-6
years generally compare poorly to NO-children in relation to gross motor proficiency.
In Chapter 6, the one leg balance ability of 514 subjects was quantitatively and
qualitatively assessed using valid norms and criteria found in literature. A positive
relationship of statistical significance (p :S 0.05) was established between the quantitative
and qualitative scores of the one leg balance in every age group. A relatively large
percentage (44.10%) of 3 year olds scored well above the average level for their age in
both types of assessment, indicating that the norms and criteria used might not be
appropriate for 3 year olds. Relatively large percentages (25.27% - 27.47%) of the 6 year
olds scored below the average level for 5 year olds in the qualitative assessment,
suggesting developmental balance delays or disorders. These findings indicate that a quantitative and qualitative assessment should be combined to assure a more accurate
assessment.
The results of Chapter 7, involving 221 male and 243 female participants, showed
significant gender differences in hopping and balancing on the right leg in favour of the
females in the 3 year old group, and in the standing long jump and throwing for distance
in favour of the males in the 5 and 6 year old groups, indicating that separate norms
should be used for the different genders when assessing standing long jump and throwing
for distance in 5 and 6 year olds.
In the light of the findings of these studies, recommendations presented in Chapter 8 for
the assessment and structuring of a programme for the optimal development of gross
motor skills in preschool children, living in urban areas in South Africa, include that: 1)
special attention should be given to the optimal development of gross motor skills of 6
year olds in a structured gross motor development programme, 2) obesity should be
addressed even in the preschool years, and activities for the specific skills shown to be
related to overweight and obesity (balance skills and catching in boys and girls and
standing long jump in boys) should also be specifically emphasized in these children, 3)
both a quantitative and a qualitative assessment should be used specifically in the one leg
balance assessment and is recommended for other fundamental motor assessments, and 4)
separate norms should be used for the assessment of the standing long jump and throwing
for distance in 5 and 6 year olds, and more emphasis should be placed on ball skills in
girls, and co-ordination skills of boys in the structuring of a movement development programme. / Thesis (Ph.D. (Human Movement Science))--Potchefstroom University for Christian Higher Education, 2002
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Interrelationships and assessment criteria of gross motor skill development and obesity of preschool children in Potchefstroom / Dorita du ToitDu Toit, Dorita January 2001 (has links)
In the holistic development of the young child, optimal gross motor development has an
important influence on optimal physical, perceptual, cognitive, language, affective-social
and normative (behavioural) development (Kapp, 1991; Gallahue & Ozmun, 1998), and
is therefore considered to be essential in the preschool years. The goal of this dissertation
was to present the results of much-needed recent research on gross motor development of
a group of children living in an urban area in South Africa, by 1) determining the current
levels of gross motor development, 2) assessing the prevalence of and the influence of
overweight and obesity on gross motor development, 3) establishing the relationship
between overweight and obesity, gross motor development and gender, 4) determining
the relationship between quantitative and qualitative assessment results of the one leg
balance, and 5) investigating the occurrence of gender differences in gross motor
development, in a group of 3-6 year old children living in Potchefstroom. These aims
were addressed by structuring the dissertation in eight chapters, Chapter 1 constituting
the introduction and statement of the problem, Chapter 2 a review of relevant literature,
Chapters 3 to 7 constituting 5 research articles addressing the specific aims of the study,
and Chapter 8 including the summary, conclusions and recommendations.
For each of the 5 research articles, the participants were 3-6 year old children (N = 514)
who lived in Potchefstroom and had been enrolled in the movement development
program (MDP) presented by movement developmentalists of the Potchefstroom
University for Christian Higher Education (P.U. for C.H.E.). Descriptive statistics
(Chapter 3-7), practical significance based on effect sizes (Chapter 4 and 5), 2 way
frequency tables and Pearson Chi-square as well as the Phi for two-way tables (Chapter
6), and t-values, degrees of difference and p-values (Chapter 7) were used. The current levels of gross motor development of preschool children in Potchefstroom
(Chapter 3) were determined by testing a total of 462 3-6 year old children (215 males
and 247 females) on 8 gross motor tasks, and comparing the results to norms and criteria
as found in the literature. The 3, 4 and 5 year olds compared favourably to their
counterparts in all the tests except for balance walk and catching, standing long jump in
the 4 year olds and throwing in the 5 year old group. The 6 year old group scored lower
than the norms and criteria in all the tests except for standing long jump, indicating
alarming implications for school readiness.
Chapter 4 and Chapter 5 examined the prevalence of and the differences in the
quantitative and qualitative execution of four gross motor tasks (standing long jump,
hopping, one leg balance and catching) between groups of overweight and obese (0) and
nonobese (NO) boys, and girls, respectively. In the male study, 17 0-participants and 49
NO-participants were compared, while 13 0-participants and 54 NO-participants were
used in the female study. Differences of practical significance (medium or large effects)
in favour of nonobese groups were found in all the quantitative and qualitative tests
among the male participants, while similar differences were found in only the
quantitative tests for the one leg balance and all the qualitative tests among the female
participants. A prevalence of overweight and obesity of 16.35% was found among the
boys and 11.81% among the girls. The results indicated that 0-children of the ages 3-6
years generally compare poorly to NO-children in relation to gross motor proficiency.
In Chapter 6, the one leg balance ability of 514 subjects was quantitatively and
qualitatively assessed using valid norms and criteria found in literature. A positive
relationship of statistical significance (p :S 0.05) was established between the quantitative
and qualitative scores of the one leg balance in every age group. A relatively large
percentage (44.10%) of 3 year olds scored well above the average level for their age in
both types of assessment, indicating that the norms and criteria used might not be
appropriate for 3 year olds. Relatively large percentages (25.27% - 27.47%) of the 6 year
olds scored below the average level for 5 year olds in the qualitative assessment,
suggesting developmental balance delays or disorders. These findings indicate that a quantitative and qualitative assessment should be combined to assure a more accurate
assessment.
The results of Chapter 7, involving 221 male and 243 female participants, showed
significant gender differences in hopping and balancing on the right leg in favour of the
females in the 3 year old group, and in the standing long jump and throwing for distance
in favour of the males in the 5 and 6 year old groups, indicating that separate norms
should be used for the different genders when assessing standing long jump and throwing
for distance in 5 and 6 year olds.
In the light of the findings of these studies, recommendations presented in Chapter 8 for
the assessment and structuring of a programme for the optimal development of gross
motor skills in preschool children, living in urban areas in South Africa, include that: 1)
special attention should be given to the optimal development of gross motor skills of 6
year olds in a structured gross motor development programme, 2) obesity should be
addressed even in the preschool years, and activities for the specific skills shown to be
related to overweight and obesity (balance skills and catching in boys and girls and
standing long jump in boys) should also be specifically emphasized in these children, 3)
both a quantitative and a qualitative assessment should be used specifically in the one leg
balance assessment and is recommended for other fundamental motor assessments, and 4)
separate norms should be used for the assessment of the standing long jump and throwing
for distance in 5 and 6 year olds, and more emphasis should be placed on ball skills in
girls, and co-ordination skills of boys in the structuring of a movement development programme. / Thesis (Ph.D. (Human Movement Science))--Potchefstroom University for Christian Higher Education, 2002
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An investigation of the determinants of private investment: the case of Botswana.Lesotlho, Patrick January 2006 (has links)
<p>Private investment in Botswana as well as a ratio to Gross Domestic Product has been falling in some periods of 1976-2003. Viewed against the background of growing evidence of a link between investment and economic growth, an inconsistent and downward trend in Botswana's private investment is a matter of concern. Several studies in developing countries emphasize the importance of macroeconomic policy in explaining variations in investment, an in particular, identify the microeconomic determinants of private investment to include interest rates, output growth, public investment, bank credit to the private sector, inflation, real exchange rate, and the level of trade. This study evaluated the macroeconomic determinants of private investment in Botswana by means of a regression analysis based on the co-integration and Error Correction Model of Engle and Granger (1987).</p>
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Documenting state employment pattern and growth during business cyclesChintaradeja, Varavuth. January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 114-116). Also available on the Internet.
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Documenting state employment pattern and growth during business cycles /Chintaradeja, Varavuth. January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 114-116). Also available on the Internet.
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A test on determinants of China's demand for international reservesHe, Yi. January 2009 (has links)
Thesis (M.A.)--Ohio University, November, 2009. / Title from PDF t.p. Includes bibliographical references.
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Essays on the volatility of macroeconomic and financial time seriesYu, Wei-Choun. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 109-116).
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