4,720 research outputs found
The expansion of manufactured exports in developing countries: An empirical assessment of supply and demand issues
Economist's thinking about the role of international trade in the process of economic development exhibits a cyclical behaviour. The classical thinking, which held sway until the 1930s, emphasized the crucial role of trade in promoting growth through the optimal allocation of resources made possible by the exploitation of international comparative advantage. By the 1950s, after years of frustration and disappointment in attempting to foster development on the basis of primary commodity exports, many economists, particularly those associated with the Latin American experience, rejected the logic of the classical argument, maintaining instead that underdevelopment is a fundamental problem of transforming the structure of an economy and not of merely achieving marginal optimality in the allocation of resources. Furthermore, imperfections of the international trading framework, such as increasing oligopolistic competition, discriminatory pricing on world markets and product differentiation, discredited deeply the idea of an export-led growth for developing countries. The economic consequence of the new viewpoint was a fundamental rejection of the market mechanism in favour of direct intervention and control of economic decision-making. The main tactic of this strategy was to force the substitution of imports with domestic production by controlling investment decisions and protecting the domestic market from international competition. By the mid-1960s, however, this strategy, or at least the tactics employed to pursue it, had proved unsuccessful (in terms of sustained growth, adequate expansion of industrial employment and removal of severe balance of payments constraints), in many instances only exacerbating problems they were designed to cure.
Generalized Kuhn-Tucker Conditions for N-Firm Stochastic Irreversible Investment under Limited Resources
In this paper we study a continuous time, optimal stochastic investment
problem under limited resources in a market with N firms. The investment
processes are subject to a time-dependent stochastic constraint. Rather than
using a dynamic programming approach, we exploit the concavity of the profit
functional to derive some necessary and sufficient first order conditions for
the corresponding Social Planner optimal policy. Our conditions are a
stochastic infinite-dimensional generalization of the Kuhn-Tucker Theorem. The
Lagrange multiplier takes the form of a nonnegative optional random measure on
[0,T] which is flat off the set of times for which the constraint is binding,
i.e. when all the fuel is spent. As a subproduct we obtain an enlightening
interpretation of the first order conditions for a single firm in Bank (2005).
In the infinite-horizon case, with operating profit functions of Cobb-Douglas
type, our method allows the explicit calculation of the optimal policy in terms
of the `base capacity' process, i.e. the unique solution of the Bank and El
Karoui representation problem (2004).Comment: 25 page
Exploring computer-generated line graphs through virtual touch
This paper describes the development and evaluation of a haptic interface designed to provide access to line graphs for blind or visually impaired people. Computer-generated line graphs can be felt by users through the sense of touch produced by a PHANToM force feedback device. Experiments have been conducted to test the effectiveness of this interface with both sighted and blind people. The results show that sighted and blind people have achieved about 89.95% and 86.83% correct answers respectively in the experiment
Design guidelines for audio presentation of graphs and tables
Audio can be used to make visualisations accessible to blind and visually impaired people. The MultiVis Project has carried out research into suitable methods for presenting graphs and tables to blind people through the use of both speech and non-speech audio. This paper presents guidelines extracted from this research. These guidelines will enable designers to implement visualisation systems for blind and visually impaired users, and will provide a framework for researchers wishing to investigate the audio presentation of more complex visualisations
Resistance of animals to parasitism as affected by a protein supplement of soybean oil meal
Call number: LD2668 .T4 1944 R5Master of Scienc
InSAR processing for the recognition of landslides
International audienceSynthetic Aperture Radar Interferometry (InSAR) is an established method for the detection and monitoring of earth surface processes. This approach has been most successful where the observed area fulfills specific requirements, such as sufficient backscattering, flat slope gradients or very slow changes of vegetation. We investigated the capability of two different InSAR techniques and achieved good results for the recognition of landslides in China and Greece that compared well with geodetic derived movement rates. This demonstrates the strong potential of SAR Interferometry for the detection of landslides and earth surface movements
Constructing sonified haptic line graphs for the blind student: first steps
Line graphs stand as an established information visualisation and analysis technique taught at various levels of difficulty according to standard Mathematics curricula. It has been argued that blind individuals cannot use line graphs as a visualisation and analytic tool because they currently primarily exist in the visual medium. The research described in this paper aims at making line graphs accessible to blind students through auditory and haptic media. We describe (1) our design space for representing line graphs, (2) the technology we use to develop our prototypes and (3) the insights from our preliminary work
Consumers\u2019 perceptions of coffee health benefits and motives for coffee consumption and purchasing
Coffee is popular worldwide and consumption is increasing, particularly in non-traditional markets. There is evidence that coffee consumption may have beneficial health effects. Consumers' beliefs in the health benefits of coffee are unclear. The study aimed at analyzing consumers' perceptions of coffee health benefits, consumption and purchasing motives of coffee consumers with positive perceptions of coffee health benefits, and willingness to pay for coffee with associated health claims. Data were collected through a face-to-face survey with consumers, resulting in a convenience sample of 250 questionnaires valid for data elaboration. Results were elaborated with factor analysis and logistic regression analysis. Findings revealed that a relevant minority of consumers believed that coffee could have positive health effects. The consumer with a positive perception of coffee health benefits is mostly male, young, works, is familiar with non-espresso-based coffee, consumes a limited amount of coffee (generally not for breakfast and often in social settings), and buys coffee at retail outlets. Consumers drink coffee for its energetic and therapeutic effects. Coffee consumption is still price-driven, but consumers are interested in purchasing coffee with associated health claims. There is the opportunity to improve the perception of coffee health benefits in consumers' minds
Understanding of the phase transformation from fullerite to amorphous carbon at the microscopic level
We have studied the shock-induced phase transition from fullerite to a dense
amorphous carbon phase by tight-binding molecular dynamics. For increasing
hydrostatic pressures P, the C60-cages are found to polymerise at P<10 GPa, to
break at P~40 GPa and to slowly collapse further at P>60 GPa. By contrast, in
the presence of additional shear stresses, the cages are destroyed at much
lower pressures (P<30 GPa). We explain this fact in terms of a continuum model,
the snap-through instability of a spherical shell. Surprisingly, the relaxed
high-density structures display no intermediate-range order.Comment: 5 pages, 3 figure
Grasp planning for a reconfigurable parallel robot with an underactuated arm structure
In this paper, a novel approach of grasp planning is applied to find out the appropriate grasp points for a reconfigurable parallel robot called PARAGRIP (Parallel Gripping). This new handling system is able to manipulate objects in the six-dimensional Cartesian space by several robotic arms using only six actuated joints. After grasping, the contact elements at the end of the underactuated arm mechanisms are connected to the object which forms a closed loop mechanism similar to the architecture of parallel manipulators. As the mounting and grasp points of the arms can easily be changed, the manipulator can be reconfigured to match the user's preferences and needs. This paper raises the question, how and where these grasp points are to be placed on the object to perform well for a certain manipulation task. <br><br> <i>This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.</i>
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