Nous étudions dans ce travail les mouvements de foule intervenant dans les situa- tions d’urgence. Nous proposons un modèle macroscopique (la foule est représentée par une densité de personnes) obéissant à deux principes très simples. Tout d’abord, chaque personne possède une vitesse souhaitée (typiquement celle qui la mène vers la sortie), qu’elle adopterait en l’absence des autres. Ensuite, la foule doit respecter une contrainte de congestion, et la densité de personnes doit rester inférieure à une valeur fixée. Cette contrainte impose une vitesse de déplacement différente de la vitesse souhaitée. Nous choisissons de prendre comme vitesse réelle celle qui est la plus proche, au sens des moindres carrés, de la vitesse souhaitée, parmi les champs de vitesses admissibles, au sens où ils respectent la contrainte de densité maximale. Le modèle obtenu s’écrit sous la forme d’une équation de transport impliquant une vitesse peu régulière a priori, et qui ne peut être étudiée par des méthodes classiques. Nous démontrons un résultat d’existence grâce à la théorie du transport optimal, tout d’abord dans le cas d’une vitesse donnée comme le gradient d’une fonction, puis dans le cas général. Nous mettons également en œuvre un schéma numérique de type catching-up : à chaque pas de temps, la densité est déplacée selon le champ de vitesse souhaitée, puis est projetée sur l’ensemble des densités admissibles. Les résultats obtenus fournissent des temps d’évacuation dont l’ordre de grandeur est proche de la réalité. / In this work, we aim at modelling crowd motion in emergency situations. We propose a macroscopic model (where people are represented as a density) following two basic principles. First, each individual has a spontaneous velocity (typically, the one which leads to the nearest exit) which would be fulfilled in the absence of other people. On the other hand, the crowd has to respect a congestion constraint, and its density must remain underneath a critical density. This constraint prevents people from following their desired velocity. The actual velocity we consider is the closest, in a mean square sense, to the desired one, among the velocities which respect the maximal density constraint.The mathematical formulation writes as a transport equation which cannot be studied with classical methods, since the real velocity field has no a priori regularity, even if the desired velocity is smooth. Thanks to the optimal transport theory, we prove an existence result, first in the case where the desired velocity is the gradient of a given function, and then in the general framework. We also propose a numerical scheme which follows the catching-up principle: at each time step, we move the density according to the spontaneous velocity, and then project it onto the space of admissible densities. The numerical results we obtain reproduce qualitatively the experimental observations

Nous étudions dans ce travail les mouvements de foule intervenant dans les situa- tions d'urgence. Nous proposons un modèle macroscopique (la foule est représentée par une densité de personnes) obéissant à deux principes très simples. Tout d'abord, chaque personne possède une vitesse souhaitée (typiquement celle qui la mène vers la sortie), qu'elle adopterait en l'absence des autres. Ensuite, la foule doit respecter une contrainte de congestion, et la densité de personnes doit rester inférieure à une valeur fixée. Cette contrainte impose une vitesse de déplacement différente de la vitesse souhaitée. Nous choisissons de prendre comme vitesse réelle celle qui est la plus proche, au sens des moindres carrés, de la vitesse souhaitée, parmi les champs de vitesses admissibles, au sens où ils respectent la contrainte de densité maximale. Le modèle obtenu s'écrit sous la forme d'une équation de transport impliquant une vitesse peu régulière a priori, et qui ne peut être étudiée par des méthodes classiques. Nous démontrons un résultat d'existence grâce à la théorie du transport optimal, tout d'abord dans le cas d'une vitesse donnée comme le gradient d'une fonction, puis dans le cas général. Nous mettons également en œuvre un schéma numérique de type catching-up : à chaque pas de temps, la densité est déplacée selon le champ de vitesse souhaitée, puis est projetée sur l'ensemble des densités admissibles. Les résultats obtenus fournissent des temps d'évacuation dont l'ordre de grandeur est proche de la réalité.

This paper investigates the growth factors of EU regions in the 1990s. We test the hypothesis that regional growth is determined by endogenous growth factors, trade and technological catching-up in a growth accounting framework. Our estimations suggest that growth of EU regions is positively related to the accumulation of physical and human capital. Innovation activity as well as international technology transfer are important for growth. The latter is facilitated if a region is well endowed with human capital. Further, we observe that technological catching-up is promoted by intensive foreign trade, a result which underlines the importance of trade openness for EU regions. (authors' abstract) / Series: EI Working Papers / Europainstitut

This dissertation provides a capability creation perspective on the story of China’s technological catching up, or resurgence, if viewed from a broader historical perspective. Since the first Asian tigers caught up to modern technological standards (e.g., South Korea, Singapore), two schools of thought have dominated causal explanations (Nelson and Pack, 1999). The first perspective is the conventional accumulation approach, which attributes the major share of growth to the accumulation of physical and human capital, and views learning as a more-or-less automatic byproduct of those investments. The second perspective is the assimilation approach, which emphasizes the arduous learning, risk-taking entrepreneurship, and innovation that is involved in the process and argues that the former proposition neglects this aspect of the endeavour and may therefore lead to erroneous estimates. This dissertation focuses on the second school of thought. Compared to the first-tier Asian tigers, the second-tier tigers, of which China is representative, pose many challenges to the assimilation approach. First, the sheer size of the country results in an unusual scale and scope of activities and interactions in any field. Second, the long history of civilization in China suggests that many modern phenomena have historical roots that are unknown to outsiders and invisible and complex to insiders. The present study aims to contribute a small piece of the puzzle to our understanding of the big picture. By providing an in-depth study of the Chinese information and communication technologies (ICT) sector, this study explores changes that have occurred in the three key building blocks of capability creation; specifically, the sourcing, generation, and appropriation of technological knowledge. A qualitative case study approach was employed for the main, empirical part of the study, which consists of extensive firm-level interviews. Complementary statistical data, including patent data and historical archives, were used to provide context and a deeper look into the study topic. The results are described in five articles. The first article presents establishing overseas research and development (R&D) laboratories as one of the major learning methods for overcoming disadvantages related to dislocation from technology sources and advanced markets. This approach allows China to search for industry-relevant scientific knowledge rather than adopting ready-made technologies introduced by western multinational enterprises in China. The second article describes the modularity-in-design approach, which opens new windows of opportunity for technological advancement. The lack of essential intellectual property rights (IPRs) acts as a key inducement and a factor-saving bias that influences the direction of innovation. When both (international) competitiveness and learning are involved in the catching-up process, the development of industry-wide capability becomes a particularly vital aspect of indigenous innovation. The third article describes the geographic consequences of historically planted industrial capabilities in China’s inland regions, which impact the absorption of different types of industrial knowledge. Fields of industry that are densely populated with patents- IPR thickets- represent a novel situation that was not experienced to the same extent by nations whose technological development occurred earlier. This thesis dedicates two articles to this dimension of knowledge appropriation. The fourth article describes the duality of Chinese ICT patenting, and the fifth article identifies an ambidextrous strategy that depends on where the major competition emerges. In general, the decision to patent and the extent of patenting are determined by four factors: a) the distance to the frontier (Aghion et al., 1997) particularly for technology; b) the nature of the technology (Teece, 1986), but with a rural extension in the case of China; c) the specificities of information (Arrow, 1962) that are embodied in a firm’s origins in China; and d) the supporting institutions that co-evolve in that process. Learning proceeds at different levels: that of individuals, firms, industries, and nations.   This dissertation provides an industry-level perspective on learning and innovation-based technological advancement. / from developing economy to global high-tech competitiveness - the case of Chinese ICT expansion

Esta tese trata do desenvolvimento industrial brasileiro sob uma perspectiva neo-schumpeteriana evolucionária no período pós-1955. A hipótese é a de que, sob o mando do que foi definido como estratégia desenvolvimentista-internacionalista, nos últimos 50 anos, o Brasil passou primeiramente por 25 anos de catching up e, em seguida, por 25 anos de falling behind. A estratégia instituída e em curso desde a segunda metade da década de 1950 foi percebida como uma ruptura com o nacional-desenvolvimentismo do segundo governo Vargas. O período 1955-1980, por meio do recurso do capital internacional, proporcionou o catching up ao paradigma em maturação da quarta revolução tecnológica. Todavia, nesse período, foram determinados os principais elementos debilitantes do ingresso do país ao novo paradigma tecnoeconômico da quinta revolução tecnológica, que irrompia já em meados da década de 1970. Está na estratégia de internacionalizar a economia, delegando às empresas multinacionais os setores-chave da dinâmica econômica nacional durante o período de catching up, o principal elemento de dependência da trajetória que condiciona desempenho presente, que é responsável pela dependência tecnológica e mantenedor da economia brasileira sob baixo dinamismo. A pesquisa também procura revisitar algumas conclusões derivadas das teses de Maria da Conceição Tavares e de João Manuel Cardoso de Mello, denominadas "tese do capitalismo tardio". Principalmente, analisa-se o argumento de que, desde a segunda metade da década de 1950, a economia brasileira estaria sujeita a ciclos endógenos e que a tendência à estagnação de longo prazo estava afastava. Percebe-se que somente foi possível aos autores, analiticamente, endogenizar as flutuações cíclicas de curto prazo da economia brasileira, porque, ao mesmo tempo, também foram endogenizados o progresso técnico e a restrição externa. Conclui-se, após analisar os últimos 50 anos de desenvolvimento industrial, que o progresso técnico não foi internalizado no país nem mesmo durante o período de catching up, e que a vulnerabilidade externa sempre se fez presente. São dois problemas estruturais, de longo prazo, que não foram resolvidos com o processo de internacionalização da economia brasileira. / This thesis discusses the Brazilian industrial development under a neo-schumpeterian perspective in the period after 1955. The hypothesis is that, under the rule of what was defined as the internationalist-development strategy, in the last 50 years, Brazil spent the first 25 years catching up and, next, the following 25 years falling behind. The strategy instituted and in course since the second half of the 50s was realized as a break up with the second Vargas government's national-developmentalism. The 1955-1980 period, by means of international funding, allowed catching up with the paradigm in maturation within the fourth technological revolution. However, in this period, it was determined the main debilitating elements for the country's entrance in the new techno-economical paradigm of the fifth technological revolution which emerged in the middle of the 70s. It is in the strategy to internationalize the economy, granting the mutinational companies the key-sectors of the national economy dynamics during the catching up period, the main element of dependence in the journey that conditions the current performance, responsible for technology subordination and keeps the Brazilian economy with low dynamism. The research also seeks to revisit some conclusions derived from Maria da Conceição Tavares' and João Manuel Cardoso de Mello's thesis, called "late capitalism thesis". Mainly, it is analyzed the argument that since the second half of the 50s the Brazilian economy would be subjected to endogenous cycles and that the tendency to long period stagnation was discarded. We notice that it was only possible for the authors, analytically, to make endogenous the Brazilian economy's cyclical fluctuations of short term, because, at the same time, technical progress and external restrictions were also made endogenous. We conclude, after analyzing the last 50 years of industrial development, that the technical progress was not internalized in the country nor even during the catching up period, and the the external vulnerability was always present. They are two long term structural problems that were not solved with the Brazilian economy internationalization process.

Esta tese trata do desenvolvimento industrial brasileiro sob uma perspectiva neo-schumpeteriana evolucionária no período pós-1955. A hipótese é a de que, sob o mando do que foi definido como estratégia desenvolvimentista-internacionalista, nos últimos 50 anos, o Brasil passou primeiramente por 25 anos de catching up e, em seguida, por 25 anos de falling behind. A estratégia instituída e em curso desde a segunda metade da década de 1950 foi percebida como uma ruptura com o nacional-desenvolvimentismo do segundo governo Vargas. O período 1955-1980, por meio do recurso do capital internacional, proporcionou o catching up ao paradigma em maturação da quarta revolução tecnológica. Todavia, nesse período, foram determinados os principais elementos debilitantes do ingresso do país ao novo paradigma tecnoeconômico da quinta revolução tecnológica, que irrompia já em meados da década de 1970. Está na estratégia de internacionalizar a economia, delegando às empresas multinacionais os setores-chave da dinâmica econômica nacional durante o período de catching up, o principal elemento de dependência da trajetória que condiciona desempenho presente, que é responsável pela dependência tecnológica e mantenedor da economia brasileira sob baixo dinamismo. A pesquisa também procura revisitar algumas conclusões derivadas das teses de Maria da Conceição Tavares e de João Manuel Cardoso de Mello, denominadas "tese do capitalismo tardio". Principalmente, analisa-se o argumento de que, desde a segunda metade da década de 1950, a economia brasileira estaria sujeita a ciclos endógenos e que a tendência à estagnação de longo prazo estava afastava. Percebe-se que somente foi possível aos autores, analiticamente, endogenizar as flutuações cíclicas de curto prazo da economia brasileira, porque, ao mesmo tempo, também foram endogenizados o progresso técnico e a restrição externa. Conclui-se, após analisar os últimos 50 anos de desenvolvimento industrial, que o progresso técnico não foi internalizado no país nem mesmo durante o período de catching up, e que a vulnerabilidade externa sempre se fez presente. São dois problemas estruturais, de longo prazo, que não foram resolvidos com o processo de internacionalização da economia brasileira. / This thesis discusses the Brazilian industrial development under a neo-schumpeterian perspective in the period after 1955. The hypothesis is that, under the rule of what was defined as the internationalist-development strategy, in the last 50 years, Brazil spent the first 25 years catching up and, next, the following 25 years falling behind. The strategy instituted and in course since the second half of the 50s was realized as a break up with the second Vargas government's national-developmentalism. The 1955-1980 period, by means of international funding, allowed catching up with the paradigm in maturation within the fourth technological revolution. However, in this period, it was determined the main debilitating elements for the country's entrance in the new techno-economical paradigm of the fifth technological revolution which emerged in the middle of the 70s. It is in the strategy to internationalize the economy, granting the mutinational companies the key-sectors of the national economy dynamics during the catching up period, the main element of dependence in the journey that conditions the current performance, responsible for technology subordination and keeps the Brazilian economy with low dynamism. The research also seeks to revisit some conclusions derived from Maria da Conceição Tavares' and João Manuel Cardoso de Mello's thesis, called "late capitalism thesis". Mainly, it is analyzed the argument that since the second half of the 50s the Brazilian economy would be subjected to endogenous cycles and that the tendency to long period stagnation was discarded. We notice that it was only possible for the authors, analytically, to make endogenous the Brazilian economy's cyclical fluctuations of short term, because, at the same time, technical progress and external restrictions were also made endogenous. We conclude, after analyzing the last 50 years of industrial development, that the technical progress was not internalized in the country nor even during the catching up period, and the the external vulnerability was always present. They are two long term structural problems that were not solved with the Brazilian economy internationalization process.

Esta tese trata do desenvolvimento industrial brasileiro sob uma perspectiva neo-schumpeteriana evolucionária no período pós-1955. A hipótese é a de que, sob o mando do que foi definido como estratégia desenvolvimentista-internacionalista, nos últimos 50 anos, o Brasil passou primeiramente por 25 anos de catching up e, em seguida, por 25 anos de falling behind. A estratégia instituída e em curso desde a segunda metade da década de 1950 foi percebida como uma ruptura com o nacional-desenvolvimentismo do segundo governo Vargas. O período 1955-1980, por meio do recurso do capital internacional, proporcionou o catching up ao paradigma em maturação da quarta revolução tecnológica. Todavia, nesse período, foram determinados os principais elementos debilitantes do ingresso do país ao novo paradigma tecnoeconômico da quinta revolução tecnológica, que irrompia já em meados da década de 1970. Está na estratégia de internacionalizar a economia, delegando às empresas multinacionais os setores-chave da dinâmica econômica nacional durante o período de catching up, o principal elemento de dependência da trajetória que condiciona desempenho presente, que é responsável pela dependência tecnológica e mantenedor da economia brasileira sob baixo dinamismo. A pesquisa também procura revisitar algumas conclusões derivadas das teses de Maria da Conceição Tavares e de João Manuel Cardoso de Mello, denominadas "tese do capitalismo tardio". Principalmente, analisa-se o argumento de que, desde a segunda metade da década de 1950, a economia brasileira estaria sujeita a ciclos endógenos e que a tendência à estagnação de longo prazo estava afastava. Percebe-se que somente foi possível aos autores, analiticamente, endogenizar as flutuações cíclicas de curto prazo da economia brasileira, porque, ao mesmo tempo, também foram endogenizados o progresso técnico e a restrição externa. Conclui-se, após analisar os últimos 50 anos de desenvolvimento industrial, que o progresso técnico não foi internalizado no país nem mesmo durante o período de catching up, e que a vulnerabilidade externa sempre se fez presente. São dois problemas estruturais, de longo prazo, que não foram resolvidos com o processo de internacionalização da economia brasileira. / This thesis discusses the Brazilian industrial development under a neo-schumpeterian perspective in the period after 1955. The hypothesis is that, under the rule of what was defined as the internationalist-development strategy, in the last 50 years, Brazil spent the first 25 years catching up and, next, the following 25 years falling behind. The strategy instituted and in course since the second half of the 50s was realized as a break up with the second Vargas government's national-developmentalism. The 1955-1980 period, by means of international funding, allowed catching up with the paradigm in maturation within the fourth technological revolution. However, in this period, it was determined the main debilitating elements for the country's entrance in the new techno-economical paradigm of the fifth technological revolution which emerged in the middle of the 70s. It is in the strategy to internationalize the economy, granting the mutinational companies the key-sectors of the national economy dynamics during the catching up period, the main element of dependence in the journey that conditions the current performance, responsible for technology subordination and keeps the Brazilian economy with low dynamism. The research also seeks to revisit some conclusions derived from Maria da Conceição Tavares' and João Manuel Cardoso de Mello's thesis, called "late capitalism thesis". Mainly, it is analyzed the argument that since the second half of the 50s the Brazilian economy would be subjected to endogenous cycles and that the tendency to long period stagnation was discarded. We notice that it was only possible for the authors, analytically, to make endogenous the Brazilian economy's cyclical fluctuations of short term, because, at the same time, technical progress and external restrictions were also made endogenous. We conclude, after analyzing the last 50 years of industrial development, that the technical progress was not internalized in the country nor even during the catching up period, and the the external vulnerability was always present. They are two long term structural problems that were not solved with the Brazilian economy internationalization process.

Fresh water collection techniques have gained significant attention due to global dwindling of fresh water resources and recent scares such as the 2011-2017 California drought. This project explores the economic viability of actively harvesting water from fog, and techniques to maximize water collection. Vapor compression and thermoelectric cooling based dehumidifier prototypes are tested in a series of experiments to assess water collection capability in foggy environments, and what parameters can increase that capability. This testing shows an approximate maximum collection rate of 1.25 L/kWh for the vapor compression prototype, and 0.32 L/kWh for the thermoelectric cooling prototype; compared to 315 L/kWh for desalination or 12 L/m2/day for passive meshes. Exploration of parameters on the thermoelectric cooling prototype show a potential increase in water collection rate of 29% with the addition of a Teflon coating to the collection surface, 15% by clearing the collection surface, and 89% by tilting certain collection surfaces by 60-75°. In combination, these parameters could push active atmospheric water harvesting into economic viability where significant infrastructure investment is not feasible.

The mobile communication technology has evolved from the first generation (1G), when the first radiotelephone service was introduced in the US in late 1940s, to the third generation (3G). In each generation, different standards and technologies were promoted by technologically and economically advanced countries. For example, the major 1G communication standards were: AMPS promoted by the US, NMT promoted by Nordic countries, and TACS promoted by the UK. The second generation (2G) communication standards include GSM promoted by the European countries and CDMA (IS-95) promoted by the US. Behind these different standards, there are entire industry chains and huge profits. To catch up with these forerunners, lagging countries usually need to go through different stages including duplicative imitation, creative imitation, and then real innovation. In the 1G era, China did not have its own standard, but it adopted the British TACS systems. In the 2G era, China did not have its own standard, and it adopted both the European GSM systems and the US CDMA systems. However, when the 3G era was approaching, China decided to seize the opportunity and developed its own 3G standard: TD-SCDMA. In January 2009, China issued three different 3G licenses to three different operators who utilized TD-SCDMA, WCDMA, and CDMA2000, respectively. The Chinese proposed 3G standard began to be commercialized with this first licensee. China has been trying to catch up with the leading countries in the mobile communication industry. This thesis examines the question of whether this catching-up process was successful or not. The purpose of this thesis is to give readers insights into the Chinese 3G market, and to help them to understand the catching-up process being undertaken by China’s mobile communication industry. The thesis first introduces some background information about 3G, TD-SCDMA, and the Chinese telecom market. Then, it reviews theories of technological catching-up and leapfrogging. After that, it presents a case study of the TD-SCDMA Industry Alliance that examines six determinants measuring the catching-up process: Sources for Competitive Advantages, Strategies and Policies, R&D Efforts, R&D Outcome, and Market Success. The final part of the thesis gives answers to the research question and reveals the profound impact brought by the catching-up process of China’s mobile industry.

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