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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.
1

The Relation between Performance and Political Connection- Evidence from China listed Corporations

Chun, Tzu 15 February 2008 (has links)
The results show that political connection has positive relation with ROE, but negative with ROA which means businessmen seek rent by from government and meanwhile, politicians extract rents from companies they manage. If members of Committee of the Chinese¡¦s People¡¦s Political Consultative Conference and firms¡¦ Community Party also serving on the board have great influence on firms¡¦ performance and resource. Besides, poor performance does not lead firms to gain political connection. Most import, power transition does not influence firms¡¦ value, especially those with old political connection.
2

Modelagem do crescimento e produ??o florestal com n?mero vari?vel de parcelas mensuradas / Modeling forest growth and yield with a variable number of measured plots

Camargos, Jos? Lucas de 23 February 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-06-06T21:08:54Z No. of bitstreams: 2 jose_lucas_camargos.pdf: 1772896 bytes, checksum: ed61126d3964190579d1888b21edf3aa (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-06-22T15:30:03Z (GMT) No. of bitstreams: 2 jose_lucas_camargos.pdf: 1772896 bytes, checksum: ed61126d3964190579d1888b21edf3aa (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-06-22T15:30:03Z (GMT). No. of bitstreams: 2 jose_lucas_camargos.pdf: 1772896 bytes, checksum: ed61126d3964190579d1888b21edf3aa (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O objetivo deste trabalho foi avaliar a influ?ncia da redu??o de parcelas em algumas medi??es de invent?rio florestal cont?nuo na modelagem do crescimento e produ??o de um povoamento de Eucalyptus sp. O modelo de Clutter foi utilizado na modelagem do crescimento e da produ??o florestal, a partir de dados selecionados de 374 parcelas distribu?das em 172 talh?es. Foram utilizadas tr?s alternativas de modelagem: sem estratifica??o do povoamento, com estratifica??o do povoamento e um conjunto de 30 simula??es. Estas simula??es foram amostras de 40 parcelas aleat?rias cada, sem estratifica??o, com o objetivo de possibilitar uma an?lise geral dos efeitos do fen?meno estudado. Em todas as alternativas, foi realizada a modelagem do crescimento e da produ??o sem considerar redu??es nas medi??es de invent?rio florestal cont?nuo e considerando tr?s situa??es de redu??o. As situa??es consideradas foram medi??es de 25%, 50% e 75% das parcelas do invent?rio florestal cont?nuo nas medi??es dois e quatro, e 100% nas medi??es um, tr?s e cinco. Esta mesma metodologia foi repetida, por?m com a utiliza??o do modelo de regress?o n?o linear Log?stico, acrescido de um fator de corre??o. Ambos os modelos apresentaram boa precis?o para a predi??o e proje??o do volume do povoamento em idades futuras. O modelo Log?stico com fator de corre??o, entretanto, foi mais preciso que o modelo de Clutter. Para ambos os modelos foi constatado que n?o houveram perdas significativas de precis?o acarretadas pelas redu??es no n?mero de parcelas em algumas medi??es do invent?rio florestal cont?nuo. Para a modelagem do crescimento e da produ??o, ? recomendado que estas redu??es sejam criteriosas e que preferencialmente a ?ltima medi??o n?o seja reduzida. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / This study had as object to evaluate the influence of the reduction of plots at some measurements of continuous forest inventory in the growth and yield modeling of a Eucalyptus sp. forest stand. The Clutter model was used in forest growth and yield modeling, using selected data of 374 distributed plots in 172 forest compartments. It were used three modeling alternatives: without stratification of the forest stand, with stratification of the forest stand and a set of 30 simulations. These simulations were samples of 40 plots each one, without stratification, objectifying a general analysis about the studied phenomenon. To all the alternatives, it was made the forest growth and yield modeling without considering reductions in continuous forest inventory measurements and considering three reduction situations. The considered situations were measurements of 25%, 50% and 75% of the continuous forest inventory plots in the measures two and four, and 100% in the measures one, three and five. This same methodology was repeated, but using the Logistic nonlinear regression model, plus a correction factor. Both models had good precision to predicting and projecting the forest stand volume at future ages. The Logistic model with a correcting factor, however, had best precision than the Clutter model. For both models it was found that there was not significant losses of accuracy caused by reductions in the number of plots at some continuous forest inventory measurements. To forest growth and yield modeling, it is recommended for these reductions to be judicious and preferably the last measurement to not be reduced.
3

Transient engine model for calibration using two-stage regression approach

Khan, Muhammad Alam Z. January 2011 (has links)
Engine mapping is the process of empirically modelling engine behaviour as a function of adjustable engine parameters, predicting the output of the engine. The aim is to calibrate the electronic engine controller to meet decreasing emission requirements and increasing fuel economy demands. Modern engines have an increasing number of control parameters that are having a dramatic impact on time and e ort required to obtain optimal engine calibrations. These are further complicated due to transient engine operating mode. A new model-based transient calibration method has been built on the application of hierarchical statistical modelling methods, and analysis of repeated experiments for the application of engine mapping. The methodology is based on two-stage regression approach, which organise the engine data for the mapping process in sweeps. The introduction of time-dependent covariates in the hierarchy of the modelling led to the development of a new approach for the problem of transient engine calibration. This new approach for transient engine modelling is analysed using a small designed data set for a throttle body inferred air ow phenomenon. The data collection for the model was performed on a transient engine test bed as a part of this work, with sophisticated software and hardware installed on it. Models and their associated experimental design protocols have been identi ed that permits the models capable of accurately predicting the desired response features over the whole region of operability. Further, during the course of the work, the utility of multi-layer perceptron (MLP) neural network based model for the multi-covariate case has been demonstrated. The MLP neural network performs slightly better than the radial basis function (RBF) model. The basis of this comparison is made on assessing relevant model selection criteria, as well as internal and external validation ts. Finally, the general ability of the model was demonstrated through the implementation of this methodology for use in the calibration process, for populating the electronic engine control module lookup tables.

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