156 research outputs found
A Study of Reduced Order 4D-VAR with a Finite Element Shallow Water Model
No full textForecast models often depend on unknown parameters, such as model initial and boundary conditions, or other tunable parameters not necessarily having any physical meaning. Calibration of these parameters to minimize errors between forecasted and observed states is called data assimilation. A common approach in this context are variational methods, of which four dimensional data variation (4D-VAR) is studied in this thesis. In 4D-VAR, a cost function is defined that penalizes misfits between observations and the corresponding numerical model results, obtained by running the model with the chosen configuration. Performing optimization with regard to this cost function yields an improved initial parameter set. Associated with this type of methods, however, are difficulties in connection with programming the adjoint model, which is needed to compute the exact gradient of the cost function. Additionally, having to integrate the adjoint model backwards in time adds significantly to the computational cost of the data assimilation process. To avoid manual implementation of adjoint code and to reduce computational complexity, approximation of the gradient calculation is considered through the use of proper orthogonal decomposition (POD), a flexible data-driven order reduction method. To facilitate this, a finite element model of the shallow water equations is tested with both the full adjoint 4D-VAR method and two different POD-reduced approaches. Twin experiments are performed and comparisons are made in terms of accuracy, computational complexity and sensitivity to perturbation and number of observation points.Applied mathematicsElectrical Engineering, Mathematics and Computer Scienc
Model reduced variational data assimilation for shallow water flow models
No full textIdentifying uncertain parameters in large-scale numerical flow models can be done using the variational method. However, for implementing the variational method the adjoint model have to be available, which requires highly complex computer code and maintenance and thus hampers its applications. To ease this problem, this thesis has explored several methods for efficiently identifying uncertain parameters in a large-scale tidal model of the entire European continental shelf which does not require the implementation of these complex adjoint code. In this study, as a first step an estimation method based on model reduction is developed and investigated for the estimation of diffusion coefficient in a simple 2D-advection diffusion model. Two projection based model reduction methods were considered, namely proper orthogonal decomposition (POD) and Balanced proper orthogonal decomposition (BPOD). In the POD based estimation method an ensemble of forward model simulations is used to determine an approximation of the covariance matrix of the model variability and a small number of the leading eigenvectors of this matrix is used to define a model subspace. By projecting the original model onto this subspace an approximate linear reduced model is obtained. Once the reduced model is available its adjoint can be implemented easily and the minimization problem is solved completely in reduced space with very low computational cost. BPOD is also a model reduction method which considers both inputs and outputs of the system while determining the reduce subspace. The estimation method has been extended by including BPOD procedure into the estimation procedure. Numerical results from a simple pollution model demonstrate that the POD based estimation approach successfully estimate the diffusion coefficient for both advection dominated problems as for diffusion dominated problems. Another important message in this study, although lots of effort had been made in constructing a reduced order model by the BPOD method, the minimization results demonstrated that both the POD and the BPOD methods performed similarly. Preliminary results showed the validity of the POD based model reduction methods for parameter estimation. As a next step, the POD based estimation method is used to calibrate numerical tidal models. Results from (twin) numerical experiments showed that the POD based calibration method performed very efficiently to estimate depth values in the selected regions of the model domain. The computational costs of the POD based calibration method are dominated by the generation of an ensemble of forward model simulations where the simulation period of the ensemble is equivalent to the timescale of the original model. It has also been found in the study that it is not needed to use a full simulations of the original model for the generation of the ensemble. The POD based calibration method has also been implemented for the estimation of the water depth and space varying bottom friction coefficient values in a very large-scale DCSM model. The recently designed large-scale spherical grid based water level model for the northwest European continental shelf (around 1000000 computational grid points) has been used for this purpose. This has been the first application of the POD based calibration method to a very large-scale model and with real data. Results from numerical experiments showed that the calibration method performs very efficiently. An overall improvement of more than 50\% was observed after the calibration in comparison with the initial model. The results also demonstrated that the POD based calibration method offered a very efficient minimization technique compared to the classical adjoint method without the burden of implementation of the adjoint. As a concluding step, to estimate depth values in the model DCSM, a Simultaneous perturbation stochastic approximation (SPSA) method has been used. The method uses stochastic simultaneous perturbation of all model parameters to generate a search at each iteration. SPSA is based on a highly efficient and easily implemented simultaneous perturbation approximation to the gradient. This gradient approximation for the central difference method uses only two objective function evaluations independent of the number of parameters being optimized. The results from experiments showed that SPSA has a lower convergence rate than POD based calibration method, however the computational cost in each iteration of the SPSA method is usually far less then the POD based calibration method. The results also demonstrated that the SPSA algorithm proved to be a promising optimization algorithm for model calibration for cases where adjoint code is not available for computing the gradient of the objective function.Applied mathematicsElectrical Engineering, Mathematics and Computer Scienc
The identification of the technical production of the IF Sudeste MG
No full textO objetivo deste estudo foi levantar os tipos de Produções Técnicas desenvolvidas pelos
docentes do quadro efetivo do IF Sudeste MG, com o intuito de identificar se o perfil da
produção acadêmica da instituição está alinhado com as diretrizes da legislação que a
normatizou.Objetivo do trabalho:
O objetivo deste estudo foi levantar os tipos de Produções Técnicas desenvolvidas pelos
docentes do quadro efetivo do IF Sudeste MG, com o intuito de identificar se o perfil da
produção acadêmica da instituição está alinhado com as diretrizes da legislação que a
normatizou.Resultados:
A extração dos dados dos docentes resultou em 1.425 Produções Técnicas registradas no
período. Foram obtidos dados importantes, como: o montante geral da Produção Técnica da
instituição, o quantitativo de produções por campi, os tipos de Produção Técnica que
apresentaram maior concentração, a constatação de que não há um tratamento similar entre a
Produção Técnica e a Produção Bibliográfica, a ausência de política regulamentadora para essa
produção e a elaboração de uma lista de atividades técnicas cadastradas pelos docentes em
outras produções.Implicações práticas:
A investigação ofereceu à sociedade o panorama da atividade de pesquisa no IF Sudeste MG,
o que contribuirá para o acesso a informações que evidenciam seu potencial mercadológico. O
levantamento das formas de Produção Técnica, além de proporcionar a identificação do
montante dos produtos, processos tecnológicos, softwares e manuais desenvolvidos pela
comunidade pesquisada, possibilitará a visualização do perfil dessa produção no IF Sudeste
MG e “a viabilidade” de trabalhos em parceria com os Arranjos Produtivos Locais.Originalidade e contribuições:
No IF Sudeste MG não há ferramentas de classificação e quantificação da Produção Técnica.
Em razão de características próprias da academia, essa produção normalmente não é registrada
nos meios de comunicação mais comuns, o que dificulta sua visibilidade, sua divulgação e seu
controle. A partir do levantamento proposto, busca-se abrir caminhos e possibilidades para que
a instituição apresente uma fonte de informação rica para a gestão da política de Ciência e
Tecnologia.Produção Técnica/Tecnológica:
A partir do estudo desenvolvido, foi possível realizar um diagnóstico da Produção Técnica do
IF Sudeste MG no intervalo de 10 anos. O estudo pode ser classificado no Eixo 4 (Serviços
Técnicos) sendo enquadrado no critério Qualis Técnico/Tecnológico - Aplicabilidade.This work aimed to identify the types of Technical Productions developed by the faculty
members of the IF Sudeste MG framework, thus allowing the identification of whether the
academic production profile of the institution is in line with the guidelines of the legislation
that instituted it.Procedures/Method for solving the problem:
For the collection of teachers' production data, the interval between the years 2008 and 2018
was considered. The period is justified by the time frame in which the Federal Institutes
complete 10 years of creation, fact that sought to evidence the evolution of the production
Teaching technique during its period of existence. The identification of the Technical
Production of the teaching staff took place through the Lattes Platform, which represents a
national standard of registration of the scientific activities of the registered researchers. The
data extraction was performed manually. In order to allow the production to be extracted, a
spreadsheet was developed in excel, which made it possible to identify, classify and
characterize the Institutional Technical Production.Results:
The extraction of the data of the teachers resulted in 1,425 Technical Productions registered in
the period. Important results were obtained, such as: the general amount of the Technical
Production of the institution, the amount of productions per campuses, which types of Technical
Production presented higher concentration, the finding that there is no similar treatment
between Technical Production and Bibliographic Production, the absence of a regulatory policy
for this production, the creation of a list of technical activities registered by teachers in other
productions.Practical implications:
The research offered to the society the panorama of the research activity in the IF Sudeste MG,
making possible the access to information that evidences the possible market potential. The
survey of the Technical Production forms, besides providing the identification of the amount of
products, technological processes, software and manuals developed by the researched
community, will allow the visualization of the profile of this production in the IF Sudeste MG
and its possibilities of works in partnerships with the arrangements local productive.Originality and contributions:
In the IF Sudeste MG there are no tools for classification and quantification of Technical
Production. Due to the academy's own characteristics, this production is not usually recorded
in the most common media, making its visibility, diffusion and control difficult. From the
proposed survey seeks to open paths and possibilities for the institution to present a rich source
of information for the management of Science and Technology policy.Technical / Technological Production:
From the study already carried out, a diagnosis of the Production Technique of the IF Sudeste
MG was carried out in the interval of 10 years. The study can be classified in Axis 4 (Technical
Services) being framed in the Technical / Technological Qualis – Applicability.105 f
Harpactus Shuckard 1837
No full textGenus Harpactus Shuckard, 1837 Arpactus Jurine, 1807: 192, junior homonym of Arpactus Panzer, 1805, and of Arpactus Panzer, 1806 (both junior synonyms of Gorytes Latreille, 1804). Type species: Arpactus formosus Jurine, 1807, designated by Shuckard 1837: 220. Harpactus Shuckard 1837: 221. Emendation of Arpactus Jurine, 107 on linguistic grounds, thus an available new name, with its own date and author (Articles 19 and 33.2). Since Harpactus is an emendation, it has the same type-species as Arpactus Jurine (Article 67.8). Harpactes Dahlbom 1843: 147, junior homonym of Harpactes Swainson, 1837 (Aves), and of Harpactes Templeton, 1834 (Arachnida). Emendation of Harpactus Shuckard. Dienoplus W.J. Fox 1894: 548. Type species: Dienoplus pictifrons Fox, 1894, by monotypy. Key to Harpactus species of India and adjacent territories 1. Head and mesosoma without distinct punctures............................................................. 2 - Head, mesosoma, [and T2] distinctly foveolate-punctate, with scattered foveae. [Kashmir].......... H. pulawskii sp. nov. 2. Propodeum with oblique and irregular striae................................................................ 3 - Propodeum with distinct coarse, longitudinal striae [Pakistan].................................. H. vividus (Turner) 3. Fore wing with fuscous patch in radial and cubital cells; propodeal enclosure red. [Northern India; Myanmar]................................................................................................. H. ornatus (Smith) - Fore wing usually without fuscous patch in radial and cubital cells; propodeal enclosure black. [Oriental India].............................................................................................. H. impudens (Nurse)Published as part of Binoy, C., Kumar, P. Girish, Monks, Joseph & Sheikh, Altaf Hussain, 2022, A review of digger wasp genus Harpactus Shuckard, 1837 (Hymenoptera Crabronidae) of the Indian subcontinent, with description of a new species and rediscovery of Harpactus impudens (Nurse, 1903), pp. 531-542 in Zootaxa 5190 (4) on page 532, DOI: 10.11646/zootaxa.5190.4.3, http://zenodo.org/record/713847
High-prevalence and high-estimated incidence of HIV infection among new injecting drug users in Estonia: need for large scale prevention programs.
No full textOBJECTIVE: To examine HIV risk behavior and HIV infection among new injectors in Tallinn, Estonia. Design and methods Data from two cross-sectional surveys of injecting drug users (IDUs) recruited from a syringe exchange program (N = 162, Study 1) or using respondent driven sampling (N = 350, Study 2). Behavioral surveys were administered; serum samples were collected for HIV testing. Subjects were categorized into new injectors (injecting 3 years). RESULTS: Twenty-eight of 161 (17%, Study 1) and 73/350 (21%, Study 2) of the study subjects were new injectors. HIV infection was substantial among the newer injectors: HIV prevalence was 50% (Study 1) and 34% (Study 2), and estimated HIV incidence 31/100 PY and 21/100 PY, respectively. In Study 2, new injectors were more likely to be female and ethnic Estonian and less likely to be injecting daily compared with long-term injectors. No significant difference was found among two groups on sharing injecting equipment or reported number of sexual partners. CONCLUSIONS: A continuing HIV epidemic among new injectors is of critical public health concern. Interventions to prevent initiation into injecting drug use and scaling up HIV prevention programs for IDUs in Estonia are of utmost importance
CRIAÇÃO DE VALOR EM AMBIENTE B2B: UMA REVISÃO DE MODELOS RELEVANTES
No full textO objetivo deste artigo é revisar modelos relevantes de prospecção da criação de valor por meio do compromisso mútuo gerado nos relacionamentos entre parceiros situados em redes de negócios no mercado business-to-business (B2B). Em outras palavras, o que se busca é estudar o processo de cocriação de valor entre players industriais. A metodologia utilizada é a revisão bibliográfica sistemática e crítica de modelagens relevantes voltadas para este estudo. Os resultados encontrados indicam que esses modelos têm apresentado crescente sofisticação, na medida em que passam a agregar elementos complementadores que buscam melhor explicar o relacionamento entre as partes envolvidas. A conclusão é de que a pesquisa acadêmica da Administração de Empresas voltada para as redes estratégicas e de relacionamentos tem mostrado crescente interesse pelo fenômeno da criação de valor por meio da interação dos agentes atuantes no mundo dos negócios nos mercados industriais. Crescentemente, a curiosidade tem se voltado para a compreensão desse processo criatório, abandonando-se o entendimento tradicional de que o valor seria algo estático e mensurável objetivamente.
Palavras-chave: Cocriação de Valor. Mercado B2B. Modelos
Aspectos Preponderantes para a Satisfação e Fidelização do Cliente: O Caso do Shopping Florence Mall
No full textO presente estudo, classificado como pesquisa quantitativa com caráter descritivo e estudo de caso, remete à medição do grau de satisfação e de fidelização do consumidor em relação aos serviços oferecidos por shopping center localizado na cidade de Juiz de Fora, em Minas Gerais. O estudo compôs-se de revisão bibliográfica sobre os tópicos abordados, que expôs as mais relevantes características do setor de serviços com foco em shopping centers, apresentou os principais traços do mercado de serviços, reviu princípios de marketing ligados às dimensões da qualidade na prestação de serviços, e resgatou as teorias de satisfação e de fidelização aplicadas ao comportamento do consumidor. Em seguida, foi realizada pesquisa quantitativa com questionário estruturado com 202 clientes do shopping no momento da compra, destinada a captar e a analisar sua percepção a respeito do tema enfocado. Como resultado da análise das variáveis estudadas, chegou-se à conclusão de que os consumidores se mostraram satisfeitos com os serviços prestados pelo shopping center analisado, sendo necessário, entretanto, estimular a fidelização do cliente
A Importância da Gestão Profissional em uma Empresa Familiar - Joalharia Meridiano Ltda DOI 10.5752/P.1984-6606.2010v10n23p40
No full textApesar de a maior parte dos estudos acadêmicos em gestão empresarial se basear em processos de gestão de empresas multinacionais e estatais, a empresa familiar, longe de ser uma instituição anacrônica nas suas diversas formas, ocupa espaço importante em economias industrializadas e emergentes. A presente pesquisa, eminentemente qualitativa, foi desenvolvida no nível exploratório, pois o objetivo é proporcionar uma visão geral acerca dos aspectos relevantes sobre o momento crítico da transição de gerações na gestão das empresas familiares. Refere-se a um caso prático que foi elaborado a partir da análise de uma empresa familiar, a Joalharia Meridiano. Esse estabelecimento, em meados dos anos de 2000, passou pelo processo de transição da gestão familiar para a gestão profissional. Ênfase também foi dirigida ao mercado do luxo, core business da empresa. O objetivo central deste artigo é expor os acontecimentos que permearam o processo de profissionalização da Meridiano. São ressaltados os entraves encontrados no decorrer desse processo, tais como as questões relativas à cultura organizacional, aos relacionamentos interpessoais, às relações de poder, à alocação de recursos, à configuração do setor, e à definição de cargos, de salários e de funções
سرسیدکامقام:حالی وشبلی کی اردوشاعری کی روشنی میں
No full textSir Syed Ahmed Khan is known as a Muslim reformer of the 19th century. He played an important role in introducing modern Urdu verse and prose. He himself was a prominent author, editor and compiler. Altaf Husain Hali is a well known poet, prose writer and critic etc. Shibli Naumani is another great name of Urdu literature. Shibli was a distinguished scholar, writer and poet. Hali and Shibli were close companions of Sir Syed. They discussed the personality and achievements of Sir Syed in their verses. The article analyses the status of Sir Syed in the light of the verse of the said two great names of Urdu.
Socio-economic determinants of employment in Mahatma Gandhi National Rural Employment Guarantee Scheme (MGNREGS) in Jammu and Kashmir
No full textPurposeThe purpose of this paper is to look at the socio-economic determinants of employment in Mahatma Gandhi National Rural Employment Guarantee Scheme (MGNREGS) in Jammu and Kashmir (J&K) at both household and individual level. My results show that there is no discrimination in provision of employment to backward classes. Out of all the Indian States, J&K has lowest female participation in the scheme. My results show that women are discriminated against in provision of employment. Worksite facilities, like creche, can positively affect female participation in the scheme.Design/methodology/approachThe author uses multi-variate OLS regression model to analyse the data collected through primary survey of three heterogenous villages of district Ganderbal of J&K.FindingsThe author finds clear evidence of discrimination against females in provision of employment along with slight evidence of elite capture of the scheme. The author also finds negative relationship between the number of children in a household and the number of workdays which highlights the importance of worksite facilities to increase female and overall participation for the scheme to be successful.Research limitations/implicationsThe possible limitation could be small sample size but given that this is the first study of its kind in the J&K State, researchers can build up on it.Originality/valueThis is one of the first research papers which looks at the performance of MGNREGS in J&K in such detail. No comprehensive study of this magnitude and rigour has been undertaken in J&K till now.</jats:sec
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