904 resultados para economics of research and experimental development


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This paper makes a formal security analysis of the current Australian e-passport implementation using model checking tools CASPER/CSP/FDR. We highlight security issues in the current implementation and identify new threats when an e-passport system is integrated with an automated processing system like SmartGate. The paper also provides a security analysis of the European Union (EU) proposal for Extended Access Control (EAC) that is intended to provide improved security in protecting biometric information of the e-passport bearer. The current e-passport specification fails to provide a list of adequate security goals that could be used for security evaluation. We fill this gap; we present a collection of security goals for evaluation of e-passport protocols. Our analysis confirms existing security weaknesses that were previously identified and shows that both the Australian e-passport implementation and the EU proposal fail to address many security and privacy aspects that are paramount in implementing a secure border control mechanism. ACM Classification C.2.2 (Communication/Networking and Information Technology – Network Protocols – Model Checking), D.2.4 (Software Engineering – Software/Program Verification – Formal Methods), D.4.6 (Operating Systems – Security and Privacy Protection – Authentication)

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Since the 1980s the concept of risk has produced a large and diverse volume of sociological research. Ulrich Beck’s groundbreaking risk society thesis provides a particularly engaging contribution, since it seems that nearly every sociological account of risk engages with this work. For Beck, we are living in second modernity – a new epoch that breaks with pre-modernity and industrial society due to the centrality, incalculability and reflexivity of globalised risk. While Beck’s theory is compelling, a reading of other theorists such as Foucault (2007[1978]) and Hacking (1975,1990) suggests that a difficulty with Beck’s work is that in attempting to explain what is novel about risk in contemporary times, he too quickly passes over the complexities and ruptures of historical change that impact on the history and contingency of risk. This paper begins by presenting a brief analysis of the present state of risk by introducing Beck’s historical narrative of risk from pre-modernity to the risk society; it then outlines the challenges with the “risk as epoch” argument by considering a range of literature, which suggests risk has a more complex history than proposed by Beck; and finally it highlights the value in examining strategies of statecraft in early modern Europe, specifically Machiavelli’s The Prince (2008[1513]) and Giovanni Botero’s political treatise, Della Ragion di Stato (1956[1589]) – as a means of more thoroughly understanding how our current concept of risk emerges. In doing so, this paper seeks to open up new trajectories in the historicisation of risk for other interested scholars.

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Student perceptions of teaching have often been used in tertiary education for evaluation purposes. However, there is a paucity of research on the validity, reliability, and applicability of instruments that cover a wide range of student perceptions of pedagogies and practices in high school settings for descriptive purposes. The study attempts to validate an inventory of pedagogy and practice (IPP) that provides researchers and practitioners with a psychometrically sound instrument that covers the most salient factors related to teaching. Using a sample of students (N = 1515) from 39 schools in Singapore, 14 factors about teaching in English lessons from the students’ perspective were tested with confirmatory factor analysis (classroom task goal, structure and clarity, curiosity and interest, positive class climate, feedback, questioning, quality homework, review of students’ work, conventional teaching, exam preparation, behaviour management, maximizing learning time, student-centred pedagogy, and subject domain teaching). Two external criterion factors were used to further test the IPP factor structure. The inventory will enable teachers to understand more about their teaching and researchers to examine how teaching may be related to learning outcomes.

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Following the discovery of the Janus kinase (JAK) 2 V617F mutation in 2005 the explosion of research and drug development activity has not only advanced our understanding of the pathogenesis of myeloproliferative neoplasms (MPNs) but also triggered debate about classification, allowed revised diagnostic and response criteria, provided a target for treatment and a mode of monitoring its success. These changes and the resultant clinical research are discussed in this article where we argue that discovery of the JAK2 V617F mutation has signalled the much delayed change in therapeutic paradigm for myelofibrosis and possibly other MPNs from palliation and allowing us to move closer to, but not yet attain, a cure.

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Este estudo investiga a influência da interação imagem-texto de três álbuns ilustrados de língua inglesa no desenvolvimento do repertório linguístico de crianças pré-leitoras. Numa metodologia de estudo de caso, adotando uma abordagem qualitativa e socio construtivista num contexto real de educação pré-escolar, três grupos de crianças portuguesas foram filmados ao longo de várias sessões de leitura repetida em voz alta e em inglês, e de sessões de recontos trabalhados em pequenos grupos. Após a transcrição das gravações, o corpus resultante foi analisado com base numa teoria fundamentada de compreensão literária e em escalas de leitura emergente. Os resultados mostraram que as crianças adotaram uma postura fortemente analítica face aos álbuns, direcionando as suas respostas para as ilustrações e usando-as como apoio na construção de significados. Os resultados mostraram também que cada interanimação visual e verbal ofereceu diversas oportunidades para o uso das línguas em presença, o português e o inglês, tendo o formato e a estrutura inerentes a cada álbum contribuído de forma muito relevante para as respostas das crianças. Contudo, os álbuns com uma dinâmica imagem-texto mais complexa proporcionaram um maior envolvimento das crianças, provocando mais discussão em torno das ilustrações e criando mais oportunidades para mediação do uso da segunda língua. Os resultados revelaram ainda a importância da interação durante as leituras repetidas, na compreensão e na análise narrativa, num processo de desenvolvimento da linguagem. Com base nestes resultados, apontam-se conclusões, com implicações para os contextos educativos, quer ao nível da língua materna, quer ao nível da segunda língua, nomeadamente em relação: à seleção de álbuns e à valorização das ilustrações e ainda à importância de leituras repetidas em voz alta e à discussão realizada pelas crianças.

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The trajectory planning of redundant robots is an important area of research and efficient optimization algorithms are needed. The pseudoinverse control is not repeatable, causing drift in joint space which is undesirable for physical control. This paper presents a new technique that combines the closed-loop pseudoinverse method with genetic algorithms, leading to an optimization criterion for repeatable control of redundant manipulators, and avoiding the joint angle drift problem. Computer simulations performed based on redundant and hyper-redundant planar manipulators show that, when the end-effector traces a closed path in the workspace, the robot returns to its initial configuration. The solution is repeatable for a workspace with and without obstacles in the sense that, after executing several cycles, the initial and final states of the manipulator are very close.

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Genetic chimeras made by aggregating early mouse embryos have many uses in developmental biology and have also provided insights into embryonic growth regulation. There is an indication that the embryo can regulate for an increase in size because although aggregation chimeras are twice as big as normal embryos when made, they are born of normal size. Upward regula..... tion of size reduced embryos is also possible. Half embryos made by the isolation or destruction of one of the blastomeres of a 2-cell embryo are also born of normal size. Little is known about the timing or the mechanism of this size regulation. In this study, the timing of size regulation in double and half embryos was clearly established by comparison of cell numbers derived from serial reconstruction of light microscope sections of control and experimental embryos. It was shown that size regulation in double embryos occurred around 6dl6h and in half embryos by 7dOh. Size regulation occurred in all tissues at the same time indicating a single control mechanism for the entire embryo. More detailed examination of the growth of double embryos revealed that size regulation occurred by alteration in cell cycle length~ No excessive cell death was found in double embryos compared to the controls and continuous labelling with [3H] thymidine showed no large non-dividing cell population in double embryos. However, a comparison of the mitotic index of double and control embryos after colcemid treatment, revealed a large difference between the two around 5dl6h to 6d16h. During this period, control embryos underwent a proliferative burst not shown by the double embryos. The mechanism for cell cycle control is not clear; it may be intrinsic to the embryo or determined by the uterine environment. Evidence was found suggesting that differentiation in the postimplantation embryo was cell number dependent. The timing of differentiative events was examined in half, double and control embryos. Proamnion formation, which occurs prior to size regulation, occurs at the same cell number but at different times in the three groups of embryos. However mesoderm which appears after size regulation was seen at the same time in all grollps of embryos.

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This paper presents the impact of integrating interventions like nutrition gardening, livestock rearing, product diversification and allied income generation activities in small and marginal coconut homesteads along with nutrition education in improving the food and nutritional security as well as the income of the family members. The activities were carried out through registered Community Based Organizations (CBOs) in three locations in Kerala, India during 2005-2008. Data was collected before and after the project periods through interviews using a pre-tested questionnaire containing statements indicating the adequacy, quality and diversity of food materials. Fifty respondents each were randomly selected from the three communities, thereby resulting in a total sample size of 150. The data was analysed using SPSS by adopting statistical tools like frequency, average, percentage analysis, t – test and regression. Participatory planning and implementation of diverse interventions notably intercropping and off-farm activities along with nutrition education brought out significant improvements in the food and nutritional security, in terms of frequency and quantity of consumption as well as diet diversity. At the end of the project, 96%of the members became completely food secure and 72% nutritionally secure. The overall consumption of fruits, vegetables and milk by both children and adults and egg by children recorded increase over the project period. Consumption of fish was more than the Recommended Dietary Intake (RDI) level during pre and post project periods. Project interventions like nutrition gardening could bring in surplus consumption of vegetables (35%) and fruits (10%) than RDI. In spite of the increased consumption of green leafy vegetables and milk and milk products over the project period, the levels of consumption were still below the RDI levels. CBO-wise analysis of the consumption patterns revealed the need for location-specific interventions matching to the needs and preferences of the communities.

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This study evaluates the effects of environmental variables on traditional and alternative agroecosystems in three Ejidos (communal lands) in the Chiapas rainforest in Mexico. The tests occurred within two seasonal agricultural cycles. In spring-summer, experiments were performed with the traditional slash, fell and burn (S-F-B) system, no-burn systems and rotating systems with Mucuna deeringiana Bort., and in the autumn-winter agricultural cycle, three no-burn systems were compared to evaluate the effect of alternative sowing with corn (no-burn and topological modification of sowing). The results show a high floristic diversity in the study area (S_S = 4 - 23%), with no significant differences among the systems evaluated. In the first cycle, the analysis of the agronomical variables of the corn indicated better properties in the fallowing systems, with an average yield of 1950 kg ha^‑1, but there was variation related to the number of years left fallow. In the second cycle, the yields were positive for the alternative technology (average yield 3100 kg ha^‑1). The traditional S-F-B systems had reduced pests and increased organic matter and soil phosphorous content. These results are the consequence of fallow periods and adaptation to the environment; thus, this practice in the Chiapas rainforest constitutes an ethnocultural reality, which is unlikely to change in the near future if the agrosystems are managed based on historical principles.

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Optimizing the composition of manure has the potential to reduce nutrient losses to the environment and to increase crop yields. In this study the effect of dietary ratios of carbon (C) to nitrogen (N) and neutral detergent fibre (NDF) to soluble carbohydrates (SC) on faeces composition of water buffalo heifers was assessed. Two digestibility trials were conducted with 12 animals each, fed one control and four test diets composed to achieve (1) high C/N and high NDF/SC ratios (HH), (2) low C/N and low NDF/SC ratios (LL), (3) high C/N and low NDF/SC ratios (HL) and (4) low C/N and high NDF/SC (LH) ratios. Faecal C/N ratios were generally lower than dietary C/N ratios, but the reduction was especially large for high C/N ratio diets (HH=55 %, HL=51 %). Faecal N concentration was positively correlated (r^2 = 0.6; P < 0.001) with N intake, but the increase in faecal N was more pronounced for diets that supplied low amounts of N. Faecal NDF concentration was positively related to NDF intake (r^2 = 0.42; P < 0.001), as well as the faecal C/N ratio (r^2 = 0.3; P < 0.001). Results demonstrate that C/N ratio and NDF concentration of buffalo manure were affected by diet composition. Diets with high C/N ratio and low NDF/SC ratio are preferable with regard to manure quality, but may not satisfy the nutritional requirements of producing animals, since N concentration in these diets was low and fibre concentration simultaneously high.

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Much of the self-image of the Western university hangs on the idea that research and teaching are intimately connected. The central axiom here is that research and teaching are mutually supportive of each other. An institution lacking such a set of relationships between research and teaching falls short of what it means to be a university. This set of beliefs raises certain questions: Is it the case that the presence of such a mutually supportive set of relationships between research and teaching is a necessary condition of the fulfilment of the idea of the university? (A conceptual question). And is it true that, in practice today, such a mutually supportive set of relationships between research and teaching characterises universities? (An empirical question). In my talk, I want to explore these matters in a critical vein. I shall suggest that: a) In practice today, such a mutually supportive set of relationships between research and teaching is in jeopardy. Far from supporting each other, very often research and teaching contend against each other. Research and teaching are becoming two separate ideologies, with their own interest structures. b) Historically, the supposed tight link between research and teaching is both of recent origin and far from universally achieved in universities. Institutional separateness between research and teaching is and has been evident, both across institutions and even across departments in the same institution. c) Conceptually, research and teaching are different activities: each is complex and neither is reducible to the other. In theory, therefore, research and teaching may be said to constitute a holy alliance but in practice, we see more of an unholy alliance. If, then, in an ideal world, a positive relationship between research and teaching is still a worthwhile goal, how might it be construed and worked for? Seeing research and teaching as two discrete and unified sets of activity is now inadequate. Much better is a construal of research and teaching as themselves complexes, as intermingling pools of activity helping to form the liquid university that is emerging today. On this view, research and teaching are fluid spaces, ever on the move, taking up new shapes, and themselves dividing and reforming, as the university reworks its own destiny in modern society. On such a perspective, working out a productive relationship between research and teaching is a complex project. This is an alliance that is neither holy nor unholy. It is an uneasy alliance, with temporary accommodations and continuous new possibilities