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Interorganisational networks, common knowledge and the reorganisation of productionBorman, Mark January 1995 (has links)
No description available.
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Essays in industrial organization : theory and practicePiga, Claudio Antonio Giuseppe January 2000 (has links)
No description available.
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Estudo teórico e experimental do comportamento das interfaces verticais de paredes interconectadas de alvenaria estrutural / Numerical and experimental study of the behaviour of vertical interfaces of interconnected structural masonry wallsOliveira, Luciane Marcela Filizola de 26 June 2014 (has links)
A ação estrutural monolítica de paredes interconectadas é dependente da resistência ao cisalhamento da interface, que por sua vez, depende do tipo de ligação entre elas. Neste contexto, o presente trabalho tem por objetivo avaliar o comportamento mecânico das interfaces verticais entre paredes de alvenaria conectadas por amarração direta e por amarração indireta com grampos de barras de aço CA-50 com 10 mm de diâmetro. Para compreensão do mecanismo de funcionamento das ligações foram realizados ensaios de caracterização dos materiais, dos componentes e da alvenaria, além de ensaios de cisalhamento direto em quatro séries de seis corpos de prova de cinco fiadas, em formato H e em escala natural. Nas séries ensaiadas foi variado o tipo de ligação e o material do bloco, sendo a primeira produzida com blocos de concreto e amarração direta, a segunda com blocos cerâmicos com amarração direta, a terceira com blocos de concreto e amarração indireta e a quarta com blocos cerâmicos e amarração indireta. Todos os corpos de prova foram assentados com argamassamento lateral e argamassa de traço 1:1:6 em volume. Na análise experimental foi investigada a força de ruptura, a relação tensão-deformação específica, o tipo de ruptura e a propagação das fissuras nas paredes. Posteriormente foram realizadas modelagens computacionais no programa DIANA, que é baseado no método dos elementos finitos, para prever o comportamento estrutural dos painéis H. A partir dos resultados experimentais e numéricos pôde-se concluir que todos os modelos romperam por cisalhamento da interface, sendo que o mecanismo resistente depende primordialmente do tipo da ligação das paredes. A resistência ao cisalhamento da interface no plano vertical de ligação entre a parede central e o flange das séries de blocos de concreto foi praticamente a mesma, independente do tipo de ligação. Já as séries de blocos cerâmicos e amarração direta apresentaram resistência ao cisalhamento aproximadamente 46% maior que a obtida para amarração indireta. Para os modelos com amarração direta o mecanismo de ruptura foi o mesmo: a tração indireta dos blocos que interceptavam o plano de cisalhamento. Para os modelos com amarração indireta a ruptura foi governada por tração indireta dos blocos da interface, no caso de blocos cerâmicos, e por escoamento das barras da armadura nos modelos de blocos de concreto. A resistência ao cisalhamento vertical da interface foi avaliada em cada caso e comparada com algumas prescrições normativas, as quais, em sua maioria, se apresentaram conservadoras. Ainda, as análises numéricas realizadas mostraram que os modelos computacionais das paredes interligadas representam adequadamente o comportamento observado em laboratório e, portanto, podem ser utilizados em análises paramétricas. A força de ruptura estimada por meio dos resultados de caracterização dos componentes apresentou boa correlação com a força obtida no ensaio de painel H, apresentando-se como um procedimento simples que pode ser utilizado de forma conservadora no desenvolvimento de projetos estruturais. / The monolithic structural behaviour of interlocked walls is dependent on the shear strength of the interface, which depends on the connection type. The present research aims to evaluate the mechanical behaviour of vertical interfaces of masonry walls connected by running bond and U-Steel anchors. The characterization testing of materials, components and masonry was carried out to understand the behaviour of the connections. Four series of tests with six H-shaped specimens were performed to determine the bonding pattern effect (running bond and U-Steel anchor) on the shear strength of the web-flange connection. In the tested series some parameters of the H-shaped specimens were varied, such as the type of connection and the block material. The first series was built with concrete blocks and running bond, the second one with clay blocks and running bond, the third one with concrete blocks and U-Steel anchors and, finally, the fourth series was constructed with clay blocks and U-Steel anchors. Face shell bedding was used to build all the specimens and the volume proportion of mortar was 1:1:6. In the experimental program the failure load, the stress-strain relationship, the type of failure and the crack propagation on the walls were investigated. Computational modelling was carried out using the FEM software Diana, which has a library with constitutive models suitable for civil engineering application, to complete the study and understand the structural behaviour of the masonry panels. The shear strength of the web-flange vertical interface, considering the specimens with concrete blocks, was nearly the same, irrespective of the connection type. Regarding the clay block series, running bond specimens were 46% stronger than the U-Steel anchor ones. Considering the running bond specimens, the failure mechanism was the same: tensile splitting of the blocks that cross the shear plane. For the U-Steel anchor models, failure was governed by tensile splitting of the blocks located in the interface plane, in the case of clay blocks, and yielding of the U- Steel anchors for concrete block specimens. The vertical shear strength of the interface was assessed in each case and compared with some normative prescriptions. In most cases the codes were conservative. Furthermore, the numerical analysis showed that the computer models of the interlocked walls represented adequately the behaviour of the physical models, and thus can be used in parametric analysis. The failure loads estimated by the results of the characterization tests of the components showed good correlation with those obtained in the tests. Based on the results, this procedure can be used conservatively in practical structural designs.
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Essays on product differentiation and tradeBacchiega, Emanuele 22 March 2005 (has links)
Product differentiation is a key feature of modern economies. Although its relevance had already been recognized in the XIX century, it is only in the last forty years that a formal treatment has been developed. The 'address approach' distinguishes between horizontal and vertical product differentiation; in the former, consumers do not agree on the quality ranking of commodities, while in the second they do. The first three chapters of this thesis deal with vertical product differentiation in an imperfectly competitive framework. In particular, the first two essays take into account the empirical evidence concerning labor requirements in the production of vertically differentiated goods in order to model labor and product markets in an upstream-downstream relation to each other. The main assumption is that higher variants of vertically differentiated commodities require highly-skilled labor. This allows to study the links between labor markets and vertically differentiated products markets, their equilibrium implications and issues of trade liberalization. The third chapter explores another side of vertical product differentiation, namely the time-to-market of vertically differentiated goods. This interval, which corresponds to the lapse of time for a product to reach the market, is studied under the assumption that firms can make it shorter through costly investments. The analysis compares firms' choices as a function of the parameters characterizing products and technologies and of market structure. The last chapter develops a general equilibrium model with imperfect competition. The concept of monopoly equilibrium is applied to a Ricardian economy in order to study the emergence of trade in that framework.
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Vertical Image Registration in StereopsisNielsen, K.R.K., Poggio, T. 01 October 1983 (has links)
Most computational theories of stereopsis require a registration stage prior to stereo matching to reduce the matching to a one-dimensional search. Even after registration, it is critical that the stereo matching process tolerate some degree of residual misalignment. In this paper, we study with psychophysical techniques the tolerance to vertical disparity in situations in which false targets abound ?? in random dot stereograms ??d eye movements are eliminated. Our results show that small amounts of vertical disparity significantly impair depth discrimination in a forced-choice task. Our main results are: a) vertical disparity of only the central "figure" part of a random dot stereogram can be tolerated up to about 3.5', b) vertical disparity of the "figure + ground" is tolerated up to about 6.5', and c) the performance of the Grimson implementation of the Marr-Poggio stereo matching algorithm for the stereograms of experiment (a) is consistent with the psychophysical results. The algorithm's tolerance to vertical disparity is due exclusively to the spatial averaging of the underlying filters. The algorithm cannot account by itself for the results of experiment (b). Eye movements, which are the principal registration mechanism for human stereopsis, are accurate to within about 7'. Our data suggest that tolerance to this residual vertical disparity is attained by two non-motor mechanisms: 1) the spatial average performed by the receptive fields that filter the two images prior to stereo matching, and 2) a non-motor shift mechanism that may be driven at least in part by monocular cues.
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Simulation of ship motion and deck-wetting due to steep random seasAdil, Adam Mohamed 17 February 2005 (has links)
The extreme motion and load of ships have been assessed using a linear frequency domain method or a linear energy spectral method and RAOs, which may be too approximate to be used for estimation of ship motion in severest seas. The new technology uses simulation in the time domain to deal with the non-linear responses to the random seas. However, the current simulation technique has been successful only up to the sea state of 7 (high seas), defined by the significant wave height of 9 meters. The above cannot provide the extreme wave loads and motions for seas higher than the sea state 7. The ultimate goal of this work would be to develop a new technique that can simulate responses to the seas of states 8 and 9. The objective of the present study is to simulate the vertical relative motion and wave topping of a moored ship in the time domain by varying the significant wave heights. The analysis was able to predict with a fair accuracy the relative motion characteristics of a freely floating body in the head and beam sea conditions. The resonance aspects and its significance in the overall response are also analyzed.
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Essays on product differentiation and tradeBacchiega, Emanuele 22 March 2005 (has links)
Product differentiation is a key feature of modern economies. Although its relevance had already been recognized in the XIX century, it is only in the last forty years that a formal treatment has been developed. The 'address approach' distinguishes between horizontal and vertical product differentiation; in the former, consumers do not agree on the quality ranking of commodities, while in the second they do. The first three chapters of this thesis deal with vertical product differentiation in an imperfectly competitive framework. In particular, the first two essays take into account the empirical evidence concerning labor requirements in the production of vertically differentiated goods in order to model labor and product markets in an upstream-downstream relation to each other. The main assumption is that higher variants of vertically differentiated commodities require highly-skilled labor. This allows to study the links between labor markets and vertically differentiated products markets, their equilibrium implications and issues of trade liberalization. The third chapter explores another side of vertical product differentiation, namely the time-to-market of vertically differentiated goods. This interval, which corresponds to the lapse of time for a product to reach the market, is studied under the assumption that firms can make it shorter through costly investments. The analysis compares firms' choices as a function of the parameters characterizing products and technologies and of market structure. The last chapter develops a general equilibrium model with imperfect competition. The concept of monopoly equilibrium is applied to a Ricardian economy in order to study the emergence of trade in that framework.
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Vertical Directionality Analysis of Low Frequency Ambient Noise in South China Sea Experiment of ASIAEXLin, Po-Chang 19 August 2004 (has links)
This study is based upon the vertical line array (VLA) in South China Sea experiment of the Asian Seas International Acoustic Experiment (ASIAEX), dated from May 3, 2001 to May 16, 2001, in which the ambient noise in shallow water was measured. In this paper, we use the beamforming method to calculate the vertical directionality of ambient noise in shallow water, for discussing the noise source distribution, and environmental effects on vertical directionality. The results show that distant shipping noise was observed near the horizontal angles, and surface noise occurred at high grazing angles. It is also discussed that the wind speed effect on the vertical directionality in this paper. Because of the typhoon Cimaron passed the experimental area during the experiment, which make wind speed changed obviously, so it can be found out the wind effect of ambient noise. By analyze the noise fluctuation, it is concluded that the threshold frequency of wind wave affected ambient noise levels were about 400 Hz. And after analyzing the vertical directionality, it is verified that the threshold was lower to 200 Hz. On the other hand, we also note the phenomena of ¡§noise notch¡¨ appeared at some duration when calculating the vertical directionality. The environmental effects (sound speed profile) on the notch, and the presentation of noise notch at different frequencies were discussed. In the end part of this paper, we determined the time when the notch occurred by using the power difference of vertical directionality, and we expect that the results would be important for similar researches in the future.
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Simulation of ship motion and deck-wetting due to steep random seasAdil, Adam Mohamed 17 February 2005 (has links)
The extreme motion and load of ships have been assessed using a linear frequency domain method or a linear energy spectral method and RAOs, which may be too approximate to be used for estimation of ship motion in severest seas. The new technology uses simulation in the time domain to deal with the non-linear responses to the random seas. However, the current simulation technique has been successful only up to the sea state of 7 (high seas), defined by the significant wave height of 9 meters. The above cannot provide the extreme wave loads and motions for seas higher than the sea state 7. The ultimate goal of this work would be to develop a new technique that can simulate responses to the seas of states 8 and 9. The objective of the present study is to simulate the vertical relative motion and wave topping of a moored ship in the time domain by varying the significant wave heights. The analysis was able to predict with a fair accuracy the relative motion characteristics of a freely floating body in the head and beam sea conditions. The resonance aspects and its significance in the overall response are also analyzed.
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The Research of Vertical Integration in Taiwan TFT-LCD Industry.Ma, Chun-Fang 19 June 2008 (has links)
TFT-LCD industry had been developed rapidly in Taiwan. Our value of output in FDP field was became the world first in 2007,it was one of the most important industry that drive economic advancement in our country. In order to keep the competition in TFT-LCD industry,to produce the relative components and material locally is the must way in the future.And many manufacturers strengthen their relationships with the component suppliers positively to reduce the production cost and enhance their ability of vertical integration.
The purpose of this research is to study the benefit of vertical integration in TFT-LCD industry.We discuss the definition,types,the motive and benefit in the part of theory and use it as the foundation of case study.In the part of case study,we took CMO as our object to study the vertical integration relationship between the vendors in supply chain. By collecting the secondary material and case interview to get the information to analyze the present situation and the future tendency of vertical integration in CMO. We generalize some conclusions as follows.
1.Cost is the key factor of vertical integration in TFT-LCD industry.
2.Technique independence is the key factor of vertical integration in TFT-LCD industry.
3.Stable supply is key factor of vertical integration in TFT-LCD industry.
4.Special area of TFT-LCD industry could strengthen the benefit of vertical integration.
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