4 resultados para Barrier to trade
em DRUM (Digital Repository at the University of Maryland)
Resumo:
This dissertation explores why some states consistently secure food imports at prices higher than the world market price, thereby exacerbating food insecurity domestically. I challenge the idea that free market economics alone can explain these trade behaviors, and instead argue that states take into account political considerations when engaging in food trade that results in inefficient trade. In particular, states that are dependent on imports of staple food products, like cereals, are wary of the potential strategic value of these goods to exporters. I argue that this consideration, combined with the importing state’s ability to mitigate that risk through its own forms of political or economic leverage, will shape the behavior of the importing state and contribute to its potential for food security. In addition to cross-national analyses, I use case studies of the Gulf Cooperation Council states and Jordan to demonstrate how the political tools available to these importers affect their food security. The results of my analyses suggest that when import dependent states have access to forms of political leverage, they are more likely to trade efficiently, thereby increasing their potential for food security.
Resumo:
The attitude of school teachers toward inclusion of children with disabilities is an important factor in the successful implementation of a national inclusion program. With the universal pressure to provide education for all and international recognition of the importance of meeting the needs of diverse populations, inclusive education has become important to governments around the world. El Salvador’s Ministry of Education seeks to establish inclusion as an integral part of their struggle to meet the needs of children across the country, but this is a difficult process, especially for a country with limited resources which still struggles to meet international expectations of educational access and quality. Teacher attitude is an important factor in the success of inclusion programs and can be investigated in relation to various factors which may affect teachers’ classroom practice. While these factors have been investigated in multiple countries, there is a need for more knowledge of the present situation in developing countries and especially in schools across the rural areas of El Salvador to meet the needs of the diverse learners in that country. My research was a mixed methods case study of the rural schools of one municipality, using a published survey and interviews with teachers to investigate their attitudes regarding inclusion. This research was the first investigation of teachers’ attitudes toward inclusion in rural El Salvador and explored the needs and challenges which exist in creating inclusive schools across this country. The findings of this study revealed the following important themes. Some children with disabilities are not in school and those with mild disabilities are not always getting needed services. Teachers agreed with the philosophy of inclusion, but believed that some children with disabilities would receive a better education in special schools. They were not concerned about classroom management. Teachers desired more training on disability and inclusion. They believed that a lack of resources, including materials and personnel, was a major barrier to inclusion. Teachers’ attitudes were consistent regardless of family and professional experience with disability or amount of inclusion training. They were concerned about the role of family support for children with disabilities.
Resumo:
Natural language processing has achieved great success in a wide range of ap- plications, producing both commercial language services and open-source language tools. However, most methods take a static or batch approach, assuming that the model has all information it needs and makes a one-time prediction. In this disser- tation, we study dynamic problems where the input comes in a sequence instead of all at once, and the output must be produced while the input is arriving. In these problems, predictions are often made based only on partial information. We see this dynamic setting in many real-time, interactive applications. These problems usually involve a trade-off between the amount of input received (cost) and the quality of the output prediction (accuracy). Therefore, the evaluation considers both objectives (e.g., plotting a Pareto curve). Our goal is to develop a formal understanding of sequential prediction and decision-making problems in natural language processing and to propose efficient solutions. Toward this end, we present meta-algorithms that take an existent batch model and produce a dynamic model to handle sequential inputs and outputs. Webuild our framework upon theories of Markov Decision Process (MDP), which allows learning to trade off competing objectives in a principled way. The main machine learning techniques we use are from imitation learning and reinforcement learning, and we advance current techniques to tackle problems arising in our settings. We evaluate our algorithm on a variety of applications, including dependency parsing, machine translation, and question answering. We show that our approach achieves a better cost-accuracy trade-off than the batch approach and heuristic-based decision- making approaches. We first propose a general framework for cost-sensitive prediction, where dif- ferent parts of the input come at different costs. We formulate a decision-making process that selects pieces of the input sequentially, and the selection is adaptive to each instance. Our approach is evaluated on both standard classification tasks and a structured prediction task (dependency parsing). We show that it achieves similar prediction quality to methods that use all input, while inducing a much smaller cost. Next, we extend the framework to problems where the input is revealed incremen- tally in a fixed order. We study two applications: simultaneous machine translation and quiz bowl (incremental text classification). We discuss challenges in this set- ting and show that adding domain knowledge eases the decision-making problem. A central theme throughout the chapters is an MDP formulation of a challenging problem with sequential input/output and trade-off decisions, accompanied by a learning algorithm that solves the MDP.
Resumo:
As unmanned autonomous vehicles (UAVs) are being widely utilized in military and civil applications, concerns are growing about mission safety and how to integrate dierent phases of mission design. One important barrier to a coste ective and timely safety certication process for UAVs is the lack of a systematic approach for bridging the gap between understanding high-level commander/pilot intent and implementation of intent through low-level UAV behaviors. In this thesis we demonstrate an entire systems design process for a representative UAV mission, beginning from an operational concept and requirements and ending with a simulation framework for segments of the mission design, such as path planning and decision making in collision avoidance. In this thesis, we divided this complex system into sub-systems; path planning, collision detection and collision avoidance. We then developed software modules for each sub-system