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A simple net ecosystem productivity model for gap filling of tower-based fluxesZisheng, Xing January 2007 (has links)
In response to global climate change, many important earth-systems-oriented science
programs have been established in the past. One such program, the Fluxnet program, studies
the response of world forests and other natural ecosystems by measuring biospheric fluxes of
carbon dioxide (CO2), water vapour, and energy with eddy-covariance (EC) techniques to
assess the role of world ecosystems in offsetting increases in CO2 emissions and related
impacts on global climate. The EC methodology has its limitations particularly when
weather is inclement and during system stoppages. These limitations create non-trivial
problems by creating data gaps in the monitored data stream, diminishing the integrity of the
dataset and increasing uncertainty with data interpretation.
This Thesis deals with the development of a parsimonious, semi-empirical approach
for gap filling of net ecosystem productivity (NEP) data. The approach integrates the effects
of environmental controls on diurnal NEP. The approach, because of its limited number of
parameters, can be rapidly optimized when appropriate meteorological, site, and NEP target
values are provided. The procedure is verified by applying it to several gap-filling case
studies, including timeseries collected over balsam fir (Abies Balsamea (L.) Mill.) forests in
New Brunswick (NB), Canada and several other forests along a north-south temperaturemoisture
gradient from northern Europe to the Middle East. The evaluation showed that the
model performed relatively well for most sites; i.e., r2 ranged from 0.68-0.83 and modelling
efficiencies, from 0.89-0.97, demonstrating the possibility of applying the model to forests
outside NB. Inferior model performance was associated with sites with less than complete
input datasets.
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Construction d'un montage de condensation de Bose--Einstein de rubidium et étude théorique d'un superfluide en rotation dans un anneauLiennard, Thomas 09 December 2011 (has links) (PDF)
Cette thèse décrit la construction d'une nouvelle expérience de condensation de Bose-Einstein visant à obtenir un condensat de rubidium 87 et à le confiner dans un piège en anneau. Une première partie est consacrée à la description du montage. Le design de l'enceinte à vide est présenté, ainsi que le système laser qui comporte une nouvelle source basée sur le doublement de fréquence d'un laser télécom. Le refroidissement des atomes dans ce montage se fait en deux parties. Un piège magnéto optique 3D est chargé par un piège magnéto-optique 2D dans une première partie de l'enceinte, puis les atomes sont transférés dans une petite cellule de verre dans laquelle a lieu le refroidissement évaporatif et la condensation. L'étape de transfert est assurée par le transport mécanique des bobines qui génèrent le champ magnétique de piégeage, et qui sont montées sur une platine de translation motorisée. Le piège final est un piège magnétique quadrupolaire bouché par un faisceau laser à 532~nm. Le montage permet d'obtenir $2\times 10^5$ atomes de rubidium dans un condensat pur en une trentaine de secondes. La seconde partie traite de l'étude théorique d'un superfluide dans un anneau 2D au moyen de simulations numériques. On y calcule d'abord la vitesse critique de rotation par l'étude du spectre des excitations de Bogolyubov du superfluide dans l'anneau, puis on utilise une simulation de l'équation de Gross-Pitaevskii pour étudier l'établissement d'un courant permanent au moyen d'un potentiel en rotation, et la stabilité d'un tel courant en présence d'une barrière de potentiel.
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Die stand van neuro-motoriese ontwikkeling en visueel-motoriese integrasie by 7- en 8-jarige leerders met leerverwante probleme / Chirine van Niekerk.Van Niekerk, Chirine January 2012 (has links)
Various researchers highlight the role of neuro-motor and visual motor integration problems on learning-related barriers (Mutti et al., 1998; Goldstein & Britt, 1994; Kulp, 1999; Lotz et al., 2005; Van Roon et al., 2010). Visual motor integration and neuro-motor problems, that include perceptual, gross- and fine motor problems further relates to writing, reading, spelling and mathematical problems (Cheatum & Hammond, 2000). The visual system plays an important role in visual motor integration and researchers found ocular-motor control to correlate with learning-related problems and are therefore investigated (Vaughn et al., 2006).
The aim of the study was twofold. The first aim was to determine the nature of neuro-motor problems that are present in 7- to 8-year old children with learning-related problems (writing, reading, spelling and mathematical problems). The second aim was to determine the nature of ocular-motor control and visual-motor integration that are present in 7- to 8-year old children with learning-related problems (writing, reading, spelling and mathematical problems).
Sixty-eight learners (45 boys and 23 girls) with and without learning-related problems took part in the study. The group with learning-related problems (n=31) consisted of learners that received remedial intervention in Grade 1 and were in Grade 2 during the data collection. The control group (n=37) represented the study group for age and gender with a mean age of 7.5 years (SD=0.43) and had no learning-related problems.
The Quick Neurological Screening Test II (QNST-II) and the Sensory Input Systems Screening Test (SISM) were used to determine the state of neuro-motor development and the visual and ocular-motor control status of learners. The Developmental Test of Visual-Motor Integration - 4th ed. (VMI-4) were used to evaluate the visual-motor integration of learners.
The Statistica for Windows 2011 computer program was used to do the data processing (StatSoft, 2011). Differences between learners with and without learning-related problems were determined by an independent t-test. A multi-dimensional representation of learners with learning-related problems were established by means of a correspondence analysis of twoway variance tables with respect to reading, writing, spelling and mathematical problems.
Results indicate that statistical as well as practical significant differences were found between learners with and without learning-related problems with respect to neuro-motor, visual-motor integration as well as ocular-motor problems. Neuro-motor problems were found between the two groups in visual, auditory, and tactile perception as well as different gross motor skills and were associated with reading, writing, spelling and mathematical problems. Regarding ocularmotor control and visual-motor integration, statistical- (p≤0,01) as well as practical (d≥0,8) significant differences were found between learners with and without learning related problems in visual-motor integration as well as 10 of the 11 sub-items of the SISM which include the following: fixation with both eyes, fixation with right eye, fixation with left eye, ocular alignment with right eye, ocular alignment with left eye, tracking with both eyes, tracking with right eye, tracking with left eye, vertical tracking and horizontal tracking.
It can be concluded from the results that a significant correlation could be found between neuro-motor problems, that includes ocular-motor control as well as visual-motor integration and learning-related problems (reading, writing, spelling and mathematical problems). Neuromotor skills as well as visual-motor integration should therefore be incorporated in intervention of children with learning-related problems. / Thesis (MA (Kinderkinetics))--North-West University, Potchefstroom Campus, 2013.
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Die stand van neuro-motoriese ontwikkeling en visueel-motoriese integrasie by 7- en 8-jarige leerders met leerverwante probleme / Chirine van Niekerk.Van Niekerk, Chirine January 2012 (has links)
Various researchers highlight the role of neuro-motor and visual motor integration problems on learning-related barriers (Mutti et al., 1998; Goldstein & Britt, 1994; Kulp, 1999; Lotz et al., 2005; Van Roon et al., 2010). Visual motor integration and neuro-motor problems, that include perceptual, gross- and fine motor problems further relates to writing, reading, spelling and mathematical problems (Cheatum & Hammond, 2000). The visual system plays an important role in visual motor integration and researchers found ocular-motor control to correlate with learning-related problems and are therefore investigated (Vaughn et al., 2006).
The aim of the study was twofold. The first aim was to determine the nature of neuro-motor problems that are present in 7- to 8-year old children with learning-related problems (writing, reading, spelling and mathematical problems). The second aim was to determine the nature of ocular-motor control and visual-motor integration that are present in 7- to 8-year old children with learning-related problems (writing, reading, spelling and mathematical problems).
Sixty-eight learners (45 boys and 23 girls) with and without learning-related problems took part in the study. The group with learning-related problems (n=31) consisted of learners that received remedial intervention in Grade 1 and were in Grade 2 during the data collection. The control group (n=37) represented the study group for age and gender with a mean age of 7.5 years (SD=0.43) and had no learning-related problems.
The Quick Neurological Screening Test II (QNST-II) and the Sensory Input Systems Screening Test (SISM) were used to determine the state of neuro-motor development and the visual and ocular-motor control status of learners. The Developmental Test of Visual-Motor Integration - 4th ed. (VMI-4) were used to evaluate the visual-motor integration of learners.
The Statistica for Windows 2011 computer program was used to do the data processing (StatSoft, 2011). Differences between learners with and without learning-related problems were determined by an independent t-test. A multi-dimensional representation of learners with learning-related problems were established by means of a correspondence analysis of twoway variance tables with respect to reading, writing, spelling and mathematical problems.
Results indicate that statistical as well as practical significant differences were found between learners with and without learning-related problems with respect to neuro-motor, visual-motor integration as well as ocular-motor problems. Neuro-motor problems were found between the two groups in visual, auditory, and tactile perception as well as different gross motor skills and were associated with reading, writing, spelling and mathematical problems. Regarding ocularmotor control and visual-motor integration, statistical- (p≤0,01) as well as practical (d≥0,8) significant differences were found between learners with and without learning related problems in visual-motor integration as well as 10 of the 11 sub-items of the SISM which include the following: fixation with both eyes, fixation with right eye, fixation with left eye, ocular alignment with right eye, ocular alignment with left eye, tracking with both eyes, tracking with right eye, tracking with left eye, vertical tracking and horizontal tracking.
It can be concluded from the results that a significant correlation could be found between neuro-motor problems, that includes ocular-motor control as well as visual-motor integration and learning-related problems (reading, writing, spelling and mathematical problems). Neuromotor skills as well as visual-motor integration should therefore be incorporated in intervention of children with learning-related problems. / Thesis (MA (Kinderkinetics))--North-West University, Potchefstroom Campus, 2013.
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加齢に伴う光合成速度と暗呼吸速度の変化がスギ人工林の総生産量及び葉群呼吸消費量の推定に及ぼす影響宮浦, 真澄, KATSUNO-MIYAURA, Masumi, 萩原, 秋男, HAGIHARA, Akio, 穂積, 和夫, HOZUMI, Kazuo 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
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An adaptive modeling and simulation environment for combined-cycle data reconciliation and degradation estimation.Lin, TsungPo 26 June 2008 (has links)
Performance engineers face the major challenge in modeling and simulation for the after-market power system due to system degradation and measurement errors. Currently, the majority in power generation industries utilizes the deterministic data matching method to calibrate the model and cascade system degradation, which causes significant calibration uncertainty and also the risk of providing performance guarantees. In this research work, a maximum-likelihood based simultaneous data reconciliation and model calibration (SDRMC) is used for power system modeling and simulation. By replacing the current deterministic data matching with SDRMC one can reduce the calibration uncertainty and mitigate the error propagation to the performance simulation.
A modeling and simulation environment for a complex power system with certain degradation has been developed. In this environment multiple data sets are imported when carrying out simultaneous data reconciliation and model calibration. Calibration uncertainties are estimated through error analyses and populated to performance simulation by using principle of error propagation. System degradation is then quantified by performance comparison between the calibrated model and its expected new & clean status.
To mitigate smearing effects caused by gross errors, gross error detection (GED) is carried out in two stages. The first stage is a screening stage, in which serious gross errors are eliminated in advance. The GED techniques used in the screening stage are based on multivariate data analysis (MDA), including multivariate data visualization and principle component analysis (PCA). Subtle gross errors are treated at the second stage, in which the serial bias compensation or robust M-estimator is engaged. To achieve a better efficiency in the combined scheme of the least squares based data reconciliation and the GED technique based on hypotheses testing, the Levenberg-Marquardt (LM) algorithm is utilized as the optimizer.
To reduce the computation time and stabilize the problem solving for a complex power system such as a combined cycle power plant, meta-modeling using the response surface equation (RSE) and system/process decomposition are incorporated with the simultaneous scheme of SDRMC. The goal of this research work is to reduce the calibration uncertainties and, thus, the risks of providing performance guarantees arisen from uncertainties in performance simulation.
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Um estudo sobre a distribuição da cota-parte do ICMS no estado de Minas GeraisBaptista, Juliana Xavier de Castro 09 December 2016 (has links)
A Constituição federal de 1988 determina em seus artigos 158 a 162 quais são as transferências
intergovernamentais de receitas fiscais entre os entes federados (União, estados, Distrito
Federal e municípios). Uma destas transferências é o repasse de 25% da arrecadação do ICMS
dos estados para os municípios denominada Cota-parte do ICMS. Dos 25% do ICMS a serem
transferidos, 75% devem ser repassados, proporcionalmente, ao VAF municipal que é o valor
adicionado nas operações relativas à circulação de mercadorias e nas prestações de serviços
realizadas em seus territórios, mais especificamente, a diferença entre as entradas e saídas de
mercadorias e serviços do município. Neste contexto, o objetivo geral desta pesquisa foi
analisar a forma de distribuição da Cota-parte do ICMS entre os 853 municípios mineiros, tendo
como objeto de estudo principal o repasse baseado no VAF que é regulamentado pela Lei
Complementar 63/1990. O período de estudo foi de 2010 a 2013 e a teoria base foi o federalismo
e o federalismo fiscal que trata da repartição de receitas fiscais entre os entes federados. Tratouse
de uma pesquisa descritiva, quantitativa e documental, realizada a partir dos relatórios
disponibilizados pela Secretaria de Estado da Fazenda de MG – SEF/MG, Siconfi/STN e
Fundação João Pinheiro – FJP. Foram aplicados os testes estatísticos Análise de Variância em
Blocos Casualizados na Estrutura Aninhada ou Hierárquica e o teste Skott-Knott para comparar
as estimativas de médias da Cota-parte do ICMS e do VAF entre os municípios e territórios de
desenvolvimento. Os resultados destes testes demostraram, por meio dos agrupamentos
formados, que não há semelhança entre elas. Para medir o grau de concentração das variáveis
foi calculado o Coeficiente de Gini e plotada a Curva de Lorenz e para verificar se existe
associação entre as variáveis VAF, PIB e Cota-parte do ICMS foi aplicado o teste Correlação
Linear de Spearman. Além destes, foi analisada a composição da receita total dos municípios
por meio de gráficos e planilhas eletrônicas. Os resultados da análise da concentração da Cotaparte
do ICMS em Minas Gerais revelaram um alto grau de concentração, mesmo sendo
incluído no cálculo os 25% repassados aos municípios por meio da aplicação dos critérios
redistributivos da Lei 18.030/2009 - Lei Hobin Hood. Revelou-se ainda que a concentração
está nos municípios que possuem maior produção de bens e serviços. / The Federal Constitution of 1988 states in its articles 158-162 which are the intergovernmental
transfers of tax revenues between the federal agencies (Federal, State, Federal District and
Municipalities). One of these transfers is the transfer of 25% of the ICMS collection of states
to municipalities called Cota-part of the ICMS. 25% of the ICMS to be transferred, 75% must
be transferred proportionally to the municipal VAF, which is the value added in the transactions
regarding the circulation of goods and the rendering of services carried out in their territories,
more specifically, the difference between the inputs and outputs of goods and services of the
Municipality. In this context, the general objective of this research is to analyze the distribution
of quota-part of the ICMS among the 853 municipalities of Minas Gerais, being the main object
of this study, the transfer based on VAF which is regulated by Complementary Law 63/1990.
The study period was from 2010 to 2013 and the base theory was federalism and fiscal
federalism which deals with the division of tax revenues between the federal entities. This was
a descriptive, quantitative and desk research conducted from reports provided by the State of
MG Finance - SEF / MG, Siconfi / STN and João Pinheiro Foundation - FJP. ANOVA statistical
tests were applied in randomized blocks in Nested or hierarchical structure and Skott-Knott test
to compare the averages of estimates of Cota-part of the ICMS and VAF between municipalities
and development of territories. The results of these tests demonstrated by means of groups
formed, there is no similarity between them. To measure the degree of concentration of the
variables we calculated the Gini coefficient and plotted the Lorenz curve and to investigate the
association between VAF variables, GDP and quota-part of the ICMS it was applied linear
correlation test of Spearman. In addition, it was analyzed the composition of the total revenue
of the municipalities through graphs and spreadsheets. The results of analyzing the
concentration of quota-part of the ICMS in Minas Gerais showed a high degree of
concentration, even being included in calculating the 25% allocated to municipalities through
the implementation of redistributive criteria of Law 18.030 / 2009 - Law Robin Hood. It also
revealed that the concentration is in the municipalities that have greater production of goods
and services. / Dissertação (Mestrado)
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An analysis of international news in Malawi newspapersKondowe, Emmanuel Braham Zumani 31 March 2008 (has links)
The study used quantitative content analysis to compare the international news content about Africa and the rest of the world in selected daily and weekly newspapers in Malawi and explored the extent to which economic factors, as represented by the Gross Domestic Product (GDP), influence news flows about Africa into Malawi. The results showed dominance of the categories of war/international conflict and politics. International news agencies were the principal sources of news items for all the four papers. Though there were differences among the newspapers in the amount of space allocated to various categories such differences were minor. The study established that GDP is not a determinant of the amount of coverage a country receives. / Communication Science / M.A. (International Communication)
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Hudební činnosti v rozvoji grafomotoriky / Music Activities and Development of GraphomotoryNevoralová, Eva January 2018 (has links)
The topic of the diploma thesis is the use of musical activities in the development of graphomotoric skills of preschool children. The theoretical section is focused on harmonising of music and movement on the level of gross and fine motoric skills. This diploma thesis analyses the musical aspect of the Czech version of the Good Start Method. The practical section presents new lessons developing graphomotoric skills with a central focus on musical and instrumental activities. The thesis provides a report on the aims, methods and progress of the field research in the preparatory classes of primary school. Part of the process is basic research into the received tempo of two songs from the Good Start Method. KEYWORDS Good Start Method, musical activities, musical skills, graphomotoric skills, gross motoric skills, fine motoric skills, rhythmic feeling
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Structure and Dynamics of the Inter-tropical Convergence zonesDixit, Vijay Vishal January 2015 (has links) (PDF)
The east-west oriented cloud bands in the tropics are called the Inter-tropical Con-vergence Zones (ITCZ). Till recently, the ITCZ has been assumed to have a simple vertical structure with convergence near the surface boundary layer and divergence near the tropopause. Recent work has shown that the ITCZ can have a complex ver-tical structure with multi-level ows. This complex structure has a profound impact on the mass, momentum and energy budget in the ITCZ. This thesis addresses the factors that govern the shallow meridional circulation that occurs in the ITCZ and the mechanisms that govern the abrupt poleward transition and the gradual poleward migration .
The shallow meridional circulation forms when the boundary layer ow that con-verges in the ITCZ, rises above the boundary layer and diverges in the lower tropo-sphere. The ow above the boundary layer is in the direction opposite to the direction of the ow within the boundary layer. Some authors have argued that this is caused by the reversal of pressure gradients just above the boundary layer in response to strong sea surface temperature gradients. This hypothesis neglects the eect of plan-etary rotation on the ow and was found to be insucient to explain the formation of shallow meridional circulation.
In the east Pacic ocean, the shallow circulation forms only to the south of the ITCZ when the ITCZ forms away from the equator, while it is absent when the ITCZ forms close to the equator. The aqua-planet simulations of the equatorial and the o-equatorial ITCZ were conducted using Community Atmosphere Model (CAM 3.0). The model used the Eulerian dynamical core with T42 horizontal resolution and 26 levels in vertical. Each simulation was run for 3 years and analysis of last six months was presented. The simulations reproduced the contrast in the vertical structure of the equatorial and o-equatorial ITCZ. The shallow circulation was simulated with-out the reversal of pressure gradients and the SST gradients were weakest when the shallow circulation was simulated. We have proposed a new mechanism for the exis-tence of shallow meridional circulation in the ITCZ. We have argued that, in Earth's atmosphere, the mean horizontal ow generally occurs in the direction perpendicular to the direction of applied pressure gradient due to the action of Coriolis force. If the local rotational eects of the ow (relative vorticity) cancels the action of the Coriolis force, then a ow along the pressure gradient is possible. We demonstrated that this condition was satised only to the south of the ITCZ when it forms away from the equator.
The ITCZ is characterized by the maximum mass convergence in the boundary layer. The mass convergence is mainly caused by the deceleration of poleward ow in the boundary layer. When the ITCZ forms close to the equator, the ow in the boundary layer is a resultant of vector addition of three forces, a pressure gradient force in the north-south direction (i.e., the ow towards low pressure), a Coriolis force which acts in the east-west direction( perpendicular to the direction of the ow), and surface friction which opposes the resultant ow. When the ITCZ forms away from the equator a three way balance does not capture the dynamics of ow. As the poleward ow is accelerated towards low pressure, it has to advect a considerable amount of zonal momentum with it which acts to retard the poleward ow. This eect of advection of zonal momentum has to be included in the force balance to obtain an accurate estimate of the ow and associated convergence.
The ITCZ acts like a heat engine. The energy is gained near the surface, some energy is transported towards pole while some is utilized in driving the meridional circulation. The rest is rejected near the tropopause. The transport within the troposphere occurs through the vertical or horizontal advection of the energy due to vertical and horizontal motions respectively. Our analysis of the ITCZ suggests that; a large amount of transport occurs through horizontal motions that was neglected in the previous studies. The detailed analysis suggests that the latent energy in the form of mass of water vapor is exported out of the ITCZ at dierent levels in association with the multilevel ows. The equatorial and the o-equatorial ITCZ are dierent because, evaporation is larger in the o-equatorial ITCZ when compared to the equatorial ITCZ.
The ITCZ shows a strong sub-seasonal variability in its location in the Indian Ocean and the west Pacic Ocean during boreal summer. There are two favorable locations, one near the equator and another away from the equator, for formation of the ITCZ. The equatorial ITCZ either propagates abruptly or gradually to the o-equatorial location. A detailed analysis of moisture and momentum budget of the simulated abrupt and gradual propagations enabled us to separate the role of thermo-dynamic and dynamic processes. We found that, if the equatorial ITCZ would propa-gate abruptly or gradually to the o-equatorial location is decided by the availability of the water vapor in the boundary layer between the two locations of the ITCZ, i.e., by the thermodynamic processes. But, such a transition to the o-equatorial location is allowed only when the constraints imposed by the re-adjustment in the circulation are satised. In simple terms, these constraints emerge due to two processes.
1. The Earth (lower boundary of the atmosphere) spins at maximum eective radius near the equator. As a result, the atmosphere gains maximum angular momentum near the equator (`zonal momentum' in Cartesian co-ordinates) .
The ITCZ is one of the primary avenues to transport the zonal momentum from the lower troposphere to the upper troposphere.
When the favorable location of ITCZ is near the equator, the location of ITCZ and the location where atmosphere gains maximum zonal momentum are coincident. The ITCZ and associated meridional circulation transports the zonal momentum upwards which is then transported polewards. As the favorable location of ITCZ moves away from the equator, the two locations are die rent. As a result, the atmospheric ow has to re-adjust so that the zonal momentum is transported from the equator to the favorable location of the ITCZ which then transports it upwards and polewards.
In summary, this thesis proposes a new mechanism for the generation of shallow meridional circulation, the abrupt transition and the gradual propagations of the ITCZ.
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