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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.
51

Energy requirements and feeding behaviour of salmonids in culture /

Bailey, Jason, January 2003 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
52

Model uncertainty in matrix exponential spatial growth regression models

Fischer, Manfred M., Piribauer, Philipp 10 1900 (has links) (PDF)
This paper considers the problem of model uncertainty associated with variable selection and specification of the spatial weight matrix in spatial growth regression models in general and growth regression models based on the matrix exponential spatial specification in particular. A natural solution, supported by formal probabilistic reasoning, is the use of Bayesian model averaging which assigns probabilities on the model space and deals with model uncertainty by mixing over models, using the posterior model probabilities as weights. This paper proposes to adopt Bayesian information criterion model weights since they have computational advantages over fully Bayesian model weights. The approach is illustrated for both identifying model covariates and unveiling spatial structures present in pan-European growth data. (authors' abstract) / Series: Department of Economics Working Paper Series
53

Estimação estocástica de parâmetros produtivos da soja uso do modelo PPDSO em um estudo de caso em Piracicaba/SP

Alambert, Marcelo Rodrigues 12 November 2010 (has links)
Submitted by Roberta Lorenzon (roberta.lorenzon@fgv.br) on 2011-06-01T14:19:41Z No. of bitstreams: 2 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia(suzinei.garcia@fgv.br) on 2011-06-01T14:54:51Z (GMT) No. of bitstreams: 2 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia(suzinei.garcia@fgv.br) on 2011-06-01T14:55:48Z (GMT) No. of bitstreams: 2 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) / Made available in DSpace on 2011-06-01T15:02:41Z (GMT). No. of bitstreams: 2 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) 65080100022.pdf: 2118563 bytes, checksum: e772406b416ab303d53d7648ac10d40b (MD5) Previous issue date: 2010-11-12 / Brazil is the second major soybean [Glycine max (L.) Merr.] producer and the seventh one on soybean oil. Brazilian production reached 61 million tons at 2008 and the forecast to 2020 is 105 million tons. Biodiesel consumption at 2008 was one million tons and the demand for this biofuel will reach 3,1 million tons at 2020. To amount this demand, the planting area on centerwest region of Brazil will increase, but also efforts on productivity must be required. Looking for a better knowledge on the climate variables temperature and global radiation over soybean development, yield and oil productivity was purposed a stochastic model with truncated normal distribution for maximum, minimum and average temperature data. Included in this model, a triangular asymmetric distribution to determine the probable oil productivity. Eight sowing dates were stipulated on Piracicaba/SP where the climate data was given from ESALQ/USP agrometeorologic station. The conclusions were: (i) there were decreases on soybean cycle duration with the average temperature increase; (ii) the soybean cycle decrease restricted soybean yield and oil productivity; (iii) the global radiation thirty days after antesis reflected on photo assimilates partition and soybean yield and oil productivity; (iv) stochastic models can be used for soybean yield and oil productivity forecast. / O Brasil é o segundo produtor mundial de soja [Glycine max (L.) Merr.] e o sétimo de óleo vegetal. A produção brasileira desta oleaginosa alcançou 61 milhões de toneladas na safra 2007/08 e projeta-se, para 2020, produção de 105 milhões de toneladas. O consumo de biodiesel em 2008 representou um milhão de toneladas e a demanda por este biocombustível deverá atingir 3,1 milhões de toneladas em 2020. Para atender esta demanda haverá ampliação da área plantada principalmente na região Centro-Oeste, mas também exigirá esforços no aumento de produtividade. Visando melhor conhecimento das inferências das variáveis climáticas temperatura e radiação global sobre o desenvolvimento da soja e sua produtividade de grãos e óleo, foi proposto um modelo estocástico com distribuição normal truncada para os dados de temperatura máxima, mínima e média. Também foi incluído neste modelo distribuição triangular assimétrica para determinação da produtividade de óleo mais provável. Foram estipuladas oito datas de semeadura para a localidade de Piracicaba/SP onde está localizada a estação meteorológica da ESALQ/USP, fornecedora dos dados climáticos utilizados neste estudo. Conclui-se que: (i) ao longo das datas de semeadura houve redução do ciclo com o aumento da temperatura média; (ii) a redução do ciclo da cultura de soja interferiu nas produtividades de grãos e de óleo; (iii) a radiação global média nos trinta dias após a antese refletiram-se na partição de fotoassimilados e na produtividade de grãos e óleo; (iv) os modelos estocásticos podem ser utilizados para a previsão das produtividades de soja e óleo.
54

Modelos não lineares resultantes da soma de regressões lineares ponderadas por funções distribuição acumulada / Nonlinear Models resulting from the sum of weighted linear regression of cumulative distribution functions

Lucas Santana da Cunha 03 February 2016 (has links)
Os controladores eletrônicos de pulverização visam minimizar a variação das taxas de insumos aplicadas no campo. Eles fazem parte de um sistema de controle, e permitem a compensação da variação de velocidade de deslocamento do pulverizador durante a operação. Há vários tipos de controladores eletrônicos de pulverização disponíveis no mercado e uma das formas de selecionar qual o mais eficiente nas mesmas condições, ou seja, em um mesmo sistema de controle, é quantificar o tempo de resposta do sistema para cada controlador específico. O objetivo desse trabalho foi estimar os tempos de resposta para mudanças de velocidade de um sistema eletrônico de pulverização via modelos de regressão não lineares, estes, resultantes da soma de regressões lineares ponderadas por funções distribuição acumulada. Os dados foram obtidos no Laboratório de Tecnologia de Aplicação, localizado no Departamento de Engenharia de Biossistemas da Escola Superior de Agricultura \"Luiz de Queiroz\", Universidade de São Paulo, no município de Piracicaba, São Paulo, Brasil. Os modelos utilizados foram o logístico e de Gompertz, que resultam de uma soma ponderada de duas regressões lineares constantes com peso dado pela função distribuição acumulada logística e Gumbell, respectivamente. Reparametrizações foram propostas para inclusão do tempo de resposta do sistema de controle nos modelos, com o objetivo de melhorar a interpretação e inferência estatística dos mesmos. Foi proposto também um modelo de regressão não linear difásico que resulta da soma ponderada de regressões lineares constantes com peso dado pela função distribuição acumulada Cauchy seno hiperbólico exponencial. Um estudo de simulação foi feito, utilizando a metodologia de Monte Carlo, para avaliar as estimativas de máxima verossimilhança dos parâmetros do modelo. / The electronic controllers spray aimed at minimizing the variation of inputs rates applied in the field. They are part of a control system, and allow for compensation for variation spray travel speed during operation. There are several types of electronic spray controllers on the market and one way to select which more efficient under the same conditions, ie in the same system of control, is to quantify the system response time for each specific driver. The objective of this study was to estimate the response times for changes in speed of an electronic spraying system via nonlinear regression models, these resulting from the sum of weighted linear regressions for cumulative distribution functions. Data were obtained on the Application Technology Laboratory, located in the Department of Biosystems Engineering from College of Agriculture \"Luiz de Queiroz\", University of Sao Paulo, in Piracicaba, Sao Paulo, Brazil. The models used were the logistic and Gompertz, resulting from a weighted sum of two constant linear regressions with weight given by the cumulative distribution function logistics and Gumbell respectively. Reparametrization been proposed for inclusion in the control system response time models, in order to improve the statistical interpretation and inference of the same. It has also been proposed a non-linear regression model two-phase which is the weighted sum of constant linear regressions weight given by a cumulative distribution function exponential hyperbolic sine Cauchy in which a simulation study was conducted using the methodology of Monte Carlo to evaluating the maximum likelihood estimates of the model parameters.
55

Modelos simétricos transformados não-lineares com diferentes distribuições dos erros: aplicações em ciências florestais

LIMA FILHO, Luiz Medeiros de Araújo 13 February 2009 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-08-03T15:09:46Z No. of bitstreams: 1 Luiz Medeiros de Araujo Lima Filho.pdf: 529199 bytes, checksum: 06cae9ad9a02975b786cf55a000dbc5b (MD5) / Made available in DSpace on 2016-08-03T15:09:46Z (GMT). No. of bitstreams: 1 Luiz Medeiros de Araujo Lima Filho.pdf: 529199 bytes, checksum: 06cae9ad9a02975b786cf55a000dbc5b (MD5) Previous issue date: 2009-02-13 / Historically, the wood of the eucalyptus is used for the most varied applications, such as; firewood, charcoal, cellulose, railway sleepers, posts for electrification, bark to tan leather, essential oils, civil construction, etc. The Gypsum Pole of Araripe in Pernambuco is a great firewood consumer for the gypsum production. Due to great need to find economical and environmental alternatives for the area, the sustainable production of eucalyptus that is a fast growth tree with great versatility has an important role. In the planning of the sustainable forest management there is a variable of extreme importance: the growth. To model the growth is fundamental in the prognosis of the productivity, site quality and dynamics of populations. Usually, the growth curves are fitted through nonlinear models developed empirically to relate, for instance, height and age. The Chapman-Richards model is a nonlinear model frequently used to model forest growth. In studies of this type, in general, it is assumed that the errors follow approximately the normal distribution. However, to model the growth assuming that the errors have a normal distribution is quite sensitive to atypical values that can happen, and generate bad estimates of the parameters. To correct that problem a new class of transformed symmetrical models was developed considering for the errors symmetrical continuous distributions with heavier tails than the normal distribution and allowing a possible nonlinear structure for the mean. With the expectation of obtaining better estimates of eucalyptus growth, it was applied to the Chapman-Richards model the following distributions of the errors: normal, t of Student, Cauchy, exponential potency, logistics I and logistics II. The t distribution of Student with 2 degrees of freedom was the most efficient to estimate height and circumference growth of eucalyptus in the Gypsum Pole of Pernambuco. / Historicamente, a madeira do Eucalyptus é usada para os mais variados fins, tais como; lenha, carvão vegetal, celulose, dormentes ferroviários, postes para eletrificação, casca para curtir couro, óleos essenciais, construção civil, etc. O Pólo Gesseiro do Araripe em Pernambuco é um grande consumidor de madeira para produção de gesso. Devido à grande necessidade de se buscar uma alternativa econômica e ambiental para a região é de interesse obter uma produção sustentável para o Eucalyptus, uma vez que esta é uma árvore de rápido crescimento e grande versatilidade. No planejamento do manejo florestal sustentado uma variável é de extrema importância: o crescimento. Sua modelagem é fundamental na prognose da produtividade, qualidade do local e dinâmica de populações. Geralmente, as curvas de crescimento são estudadas por meio de modelos não-lineares desenvolvidos empiricamente para relacionar, por exemplo, altura e idade. Um modelo não-linear bastante utilizado na prática para modelar curvas de crescimento é o modelo de Chapman-Richards. Em estudos deste tipo, em geral, assume-se que os erros seguem distribuição normal. Contudo, a modelagem sob a suposição de erros com distribuição normal é bastante sensível a valores atípicos que por ventura possam ocorrer, podendo distorcer as estimativas dos parâmetros. Para corrigir esse problema Cordeiro et al. (2009) desenvolveram uma nova classe de modelos simétricos transformados considerando para os erros distribuições contínuas simétricas com caudas mais pesadas do que a distribuição normal e permitindo uma possível estrutura não-linear para a média. Dessa forma, com a expectativa de obter melhores estimativas de crescimento de Eucalyptus, aplicaram-se ao modelo de Chapman-Richards as seguintes distribuições dos erros: normal, t de Student, Cauchy, exponencial potência, logística I e logística II que apresentou a distribuição t de Student com 2 graus de liberdade com melhores estimativas de crescimento em altura e circunferência de Eucalyptus no Pólo Gesseiro de Pernambuco.
56

Modelo de crescimento, com variáveis ambientais, para o ipê felpudo em diferentes espaçamentos. / Growth model, with ambiental variables, for ipê felpudo in different plantation densities.

Clariça Cacciamali de Souza 01 October 2004 (has links)
O Ipê Felpudo (Zehyera tuberculosa (Vell) Bur) é uma espécie nativa, pioneira que possui um alto potencial silvicultural. Essa está ameaçada de extinção devido ao caráter extrativista e predatório da exploração florestal brasileira. A eliminação de complexos ecossistemas florestais por atividades agrícolas, agropecuárias, madeireiras e industriais tem levado a drásticas reduções da base genética dessa essência. O espaçamento é de grande importância para o desenvolvimento das árvores sob aspectos tecnológicos, silviculturais e econômicos. Esse influencia na morfologia e crescimento das árvores. O espaçamento ótimo é aquele que concorrerá para o maior volume do produto e a qualidade almejada. A modelagem florestal inicia-se no inventário de parcelas permanentes que sofrem remedições, pois as florestas são um sistema biológico que está sempre em mudanças e, necessita-se da projeção destas mudanças para que se possa tomar decisões necessárias a fim de ser executado um manejo adequado nesse ecossistema. As decisões de manejo são baseadas em informações sobre as situações atuais e futuras dos povoamentos.Os objetivos desse trabalho são: analisar um experimento com 6 diferentes espaçamentos; definir um modelo de crescimento para a espécie, em função de variáveis do povoamento e climáticas coletadas na Estação Experimental de Linhares, Espírito Santo. / The Ipê Felpudo (Zeyhera tuberculosa (Vell) Bur) is a native and pioneer species, which possesses a high silvicultural potencial. It has been threatened of extinguishing due the intense predatory exraction of the Brazilian forestry exploitation. The elimination of the complex forestry ecosystem for agricultural, farming, lumber and industrial activities has induced to the drastic redutions of it’s genetic base. Plantation density is one of the most important factor or is the most important factor has a great importance for the development of the trees under technological, sivicultural and economic aspects. It influences in the morphological and trees growth. The excellent plantation density is the one that will concur for the biggest volume of the product and it’s quality. Forest modeling initiates through the inventory of permanent plots that suffer remeasures, therefore, forests are biological systems that are always changing and requires a projection of theese changes, in order to permit executinge management adjustments in this ecosystem. This decisions are based on information of the current and future situations of the stand. The purposes of this work are: to analyze an experiment with 6 different plantation densities; to define a growth model for this species, with stand and climatic variables, collected in the Experimental Station of Linhares, Espírito Santo.
57

Ekonomické růstové modely ve stochastickém prostředí / Economic Growth Models in Stochastic Environment

Uhliar, Miroslav January 2017 (has links)
No description available.
58

Méthodes statistiques pour la différenciation génotypique des plantes à l’aide des modèles de croissance / Statistical methods for the genotypic differentiation of plants using growth models

Viaud, Gautier 22 January 2018 (has links)
Les modèles de croissance de plantes peuvent être utilisés afin de prédire des quantités d’intérêt ou évaluer la variabilité génotypique au sein d’une population de plantes ; ce double usage est mis en évidence au sein de ce travail. Trois modèles de plantes sont ainsi considérés (LNAS pour la betterave et le blé, GreenLab pour Arabidopsis thaliana) au sein du cadre mathématique des modèles à espace d’états généraux.Une nouvelle plate-forme de calcul générique pour la modélisation et l’inférence statistique (ADJUSTIN’) a été développée en Julia, permettant la simulation des modèles de croissance de plantes considérés ainsi que l’utilisation de techniques d’estimation de pointe telles que les méthodes de Monte Carlo par chaînes de Markov ou de Monte Carlo séquentielles.L’inférence statistique au sein des modèles de croissance de plantes étant de première importance pour des applications concrètes telles que la prédiction de rendement, les méthodes d’estimation de paramètres et d’états au sein de modèles à espaces d’états et dans un cadre bayésien furent tout d’abord étudiées, et plusieurs cas d’étude pour les plantes considérées sont analysés pour le cas d’une plante individuelle.La caractérisation de la variabilité au sein d’une population de plantes est envisagée à travers les distributions des paramètres de population au sein de modèles hiérarchiques bayésiens. Cette approche requérant l’acquisition de nombreuses données pour chaque individu, un algorithme de segmentation-suivi pour l’analyse d’images d’Arabidopsis thaliana, obtenues grâce au Phénoscope, une plate-forme de phénotypage à haut rendement de l’INRA Versailles, est proposé.Finalement, l’intérêt de l’utilisation des modèles hiérarchiques bayésiens pour la mise en évidence de la variabilité au sein d’une population de plantes est discutée. D’abord par l’étude de différents scénarios sur des données simulées, et enfin en utilisant les données expérimentales obtenues à partir de l’analyse d’images pour une population d’Arabidopsis thaliana comprenant 48 individus. / Plant growth models can be used in order to predict quantities of interest or assess the genotypic variability of a population of plants; this dual use is emphasized throughout this work.Three plant growth models are therefore considered (LNAS for sugar beet and wheat, GreenLab for Arabidopsis thaliana) within the mathematical framework of general state space models.A new generic computing platform for modelling and statistical inference (ADJUSTIN’) has been developed in Julia, allowing to simulate the plant growth models considered as well as the use of state-of-the-art estimation techniques such as Markov chain Monte Carlo and sequential Monte Carlo methods.Statistical inference within plant growth models is of primary importance for concrete applications such as yield prediction, parameter and state estimation methods within general state-space models in a Bayesian framework were first studied and several case studies for the plants considered are then investigated in the case of an individual plant.The characterization of the variability of a population of plants is envisioned through the distributions of parameters using Bayesian hierarchical models. This approach requiring the acquisition of numerous data for each individual, a segmentation-tracking algorithm for the analysis of images of Arabidopsis thaliana, obtained thanks to the Phenoscope, a high-throughput phenotyping platform of INRA Versailles, is proposed.Finally, the interest of using Bayesian hierarchical models to evidence the variability of a population of plants is discussed. First through the study of different scenarios on simulated data, and then by using the experimental data acquired via image analysis for the population of Arabidopsis thaliana comprising 48 individuals.
59

Enhancing Profitability of Pond Aquaculture in Ghana through Resource Management and Environmental Best Management Practices

Ansah, Yaw Boamah 09 December 2014 (has links)
The accelerating pace of growth of aquaculture in sub-Saharan Africa has received much positive appraisal because of the potential of the industry to contribute to economic development and food security by providing jobs and animal protein. Adoption of best management practices (BMPs) holds the potential to ameliorate the related environmental impacts of aquaculture, such as in the amounts of nutrients and sediment that will enter natural water bodies from earthen pond effluents. The goals of this study were to characterize adoption of aquaculture BMPs on small-scale, pond-based farms in Ghana, and to assess selected economic, social, and environmental outcomes of BMP adoption. Two BMPs: 1) water reuse, and 2) commercial floating feeds, were investigated for adoption by pond-based fish farmers in Ghana. I conducted my study in Ghana using on-farm experiments involving intensive monitoring of water quality and growth of Nile tilapia (Oreochromis niloticus) over two production cycles. Additionally, I administered a baseline survey to 393 (and a follow-up survey to 160) fish farmers. I determined the best model for modelling farmed Nile tilapia growth with multi-model inference based on Akaike information criterion (AIC), the profitability of adopting BMPs with stochastic enterprise budgets and, social welfare impact with the Economic-Surplus model. I used a Markov model to predict the equilibrium rate of adoption of the two BMPs and determined the impact of BMP adoption on the reduction of pollutant loading with the Minimum-Data method of the Tradeoffs Analysis (TOA-MD). My results showed that the logistic model is a better alternative to the von Bertalanffy model for modelling the growth of Oreochromis niloticus under pond aquaculture conditions. There were no significant differences in fish weight between the water re-use BMP and the use of new water. Adoption of the commercial floating feed BMP resulted in a 100% increase in fish final weight and yield, and in higher profitability, compared to the sinking feed type. Probability of making a profit was highest (72%) in the scenario with commercial feed and self-financing. Net present values (NPV) of about US$ 11 million and US$ 375 million could be obtained from the adoption of commercial floating feed and Genetically-Improved Farm Tilapia (GIFT) strain, respectively, in Ghana. Hence, any innovation that has a significant impact on fish yield also will have a significant impact on mean NPV and social welfare. However, I identified a number of potential negative ecological and genetic impacts exist from introducing the GIFT strain into Africa from Asia. Although considered low-intensity production systems, nutrients and solids in study ponds were found to be higher than levels expected in intensive culture ponds by wide margins. Pond water quality was significantly higher with commercial floating feed. The water-reuse BMP also prevented pollutants from leaving ponds altogether for the number of cycles for which pond water was reused, especially if associated BMPs such as rainfall capture and avoidance of water exchange are observed. Significant reductions in the loading of all water quality variables (nitrogen, phosphorus, solids, and BOD5) could be achieved with the adoption of the recommended feed type in Ghana. Adoption of the water reuse BMP has the potential to cause pollution reductions of 200% - 3,200% above that from the floating feed BMP. The strongest influence on the combined adoption of these BMPs were from : farmer's awareness of the feed BMP, perceived necessity and relative profitability of the water reuse BMP, and farmer's years of experience. A combination of central media (workshops), demonstrations, and lateral diffusion was found to be the most effective channel for disseminating these BMPs. Maximum adoption rate of the feed BMPs was estimated to be 38% - 58%. Also, US$ 6,000/year and US$12,000/year need to be paid per 0.6 ha pond surface area to push adoption of the feed BMP to 50% and 70%, respectively. Hence, to ensure the successful adoption of aquaculture BMPs, I recommend that regular well-planned workshops be organized to create awareness and a conducive atmosphere to target farmers at multiple stages of the innovation decision process. Incentives and effective dissemination will encourage the adoption of these and other environmental BMPs. Feed costs need to be lowered in order to encourage the adoption of commercial floating feed in Ghana. Future analyses could quantify the differences in production costs between using the two water types, to reveal the possible higher relative profitability of pond water reuse over draining ponds after each production cycle. Also, African governments are advised to commission rigorous baseline and ecological risk analyses before adoption of the GIFT strain. Improvements in management practices and infrastructure could increase the yield and profitability of the local strains even if genetically-improved strains are not introduced. / Ph. D.
60

Early stages of technology intensive companies

Muhos, M. (Matti) 03 June 2011 (has links)
Abstract This study aims to clarify the early development stages of technology intensive companies. The current literature does not offer an extensive review of stage perspectives for company growth – the overall picture of the field is somewhat vague. The evolution of this field remains unclear as well as the current state. Further, recent empirical stage models focusing on technology intensive companies have not been delineated. As companies move through their early stages, they face events which contribute to or detract from their aim. A study focusing on these events may provide fresh viewpoints for understanding the management processes. This study seeks to clarify how the literature describes the early stages of technology intensive companies, and what viewpoints are highlighted by the management as a company progresses through these sequences. This retrospective multiple case study clarifies the topic with two meta-analyses and a sequential incident study carried out in ten young technology intensive companies in Finland and Thailand. First, well covered areas, trends, and ideas for fresh approaches are studied through a meta-analysis of the past 60 years of literature focusing on stages of development. Based on recent empirical studies, a sequential self assessment framework is formed. Second, it is studied whether the case study methodology could be utilised to further clarify the early stages of technology intensive companies. Third, the experiences of ten case companies are reflected through the framework in order to test the framework, and to study what viewpoints these cases reveal about the early stages of technology intensive companies. This study provided an extensive review of the research focusing on the stages of development. A four-stage framework was found applicable for a self-assessment of the early stages in technology intensive companies, while ten case studies and cross case analysis provided partial support for the framework. In addition, this study provided many potential fresh viewpoints for a theory related to the early stages of technology intensive companies. These viewpoints are considered here as starting points for further research, which is expected to provide sufficient evidence for further modification of the framework. / Tiivistelmä Tämän tutkimuksen tavoitteena on selkeyttää teknologiaintensiivisten yritysten varhaisia kehitysvaiheita. Kirjallisuus ei tarjoa kattavaa katsausta yrityksen kehitysvaiheita käsittelevästä tutkimuksesta – kokonaiskuva aiheesta jää jokseenkin epämääräiseksi samoin kuin alan kehitys ja nykytila. Lisäksi viimeaikaisten empiiristä aineistoa sisältävien vaihemallien tuloksia ei ole koottu yhteen. Varhaisissa kehitysvaiheissaan yritykset kohtaavat sekä tavoitteitaan edistäviä että estäviä tapahtumia. Tapahtumia tutkimalla on mahdollista nostaa esille tuoreita näkökulmia varhaisiin vaiheisiin liittyviin johtamisprosesseihin. Tämä tutkimus pyrkii selvittämään, kuinka teknologiayrityksen varhaiset kehitysvaiheet on kuvattu kirjallisuudessa ja mitä näkökulmia varhaisen kehityksen läpi käyneiden yritysten johto korostaa. Tämä takautuva monitapaustutkimus analysoi aihetta kahden meta-analyysin ja vaiheittain toteutetun kriittiset tapahtumat -menetelmän avulla. Tapaustutkimus suoritettiin kymmenessä suomalaisessa ja thaimaalaisessa yrityksessä. Ensiksi 60 edeltävää vuotta käsittävässä meta-analyysissä analysoitiin vaihemallien historia ja nykytila, trendit ja potentiaaliset ideat uusille lähestymistavoille. Viimeaikaisten empiiristen tutkimusten perusteella muodostettiin synteesi varhaisten kehitysvaiheiden itsearviointikehykseksi. Toiseksi tutkittiin voidaanko tapaustutkimusta hyödyntämällä edelleen selventää teknologiaintensiivisten yritysten varhaisia kehitysvaiheita. Kolmanneksi kymmenen tapausyrityksen kokemuksia peilattiin itsearviointikehykseen tarkoituksena testata kehystä ja analysoida mitä näkökulmia tapaukset paljastavat teknologiaintensiivisten yritysten varhaisista vaiheista. Tutkimus tarjosi laajan katsauksen yrityksen kehitysvaiheisiin keskittyvään tutkimuskenttään. Nelivaiheinen kehys todettiin soveltuvaksi varhaisten kehitysvaiheiden itsearviointiin teknologiaintensiivisissä yrityksissä – kymmenen tapausta ja näiden vertailu antoi osittaisen tuen tälle. Lisäksi tutkimus tarjosi useita uusia näkökulmia teknologiaintensiivisten yritysten varhaisia kehitysvaiheita käsittelevään teoriaan. Nämä näkökulmat toimivat lähtökohtana jatkotutkimuksille, joiden oletetaan tuovan riittävästi todistusaineistoa itsearviointikehyksen edelleenkehittämiseksi.

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