989 resultados para Price Control


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One way to do a bibliometric study is to examine each of the records that make up a database, each record and extract key areas that may disclose relevant information about the use of the database and documents in the collection . This article shows how a reference database allows to obtain important data that can reach conclusions that in some cases surprising. For this study we used the following fields of Database Control Documentary Indigenous Nationalities of Costa Rica 1979-2003: author, place of publication, publisher, year, language and support. The database analyzed has two thousand records and was developed in the Winisis. Moreover, analysis of documents was made after processing of the data, which was to export records to Excel software Winisis. After this information extracted from their chosen fields and are held by their respective separate chart or graph to present the results obtained. Furthermore, we show the application of different methods to learn more about the scientific aspects as: the Price Index, the Index of Collaboration This contribution will, first, for (as) students in the course of the race Metric Studies of Library and Information Science, National University, demonstrate and practice what you learned in this area. They may also benefit the (as) professionals from different areas, such as anthropologists (as), sociologists (as), linguists and librarians (as), among others (as).

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OBJECTIVE: Pricing strategies are a promising approach for promoting healthier dietary choices. However, robust evidence of the cost-effectiveness of pricing manipulations on dietary behaviour is limited. We aimed to assess the cost-effectiveness of a 20% price reduction on fruits and vegetables and a combined skills-based behaviour change and price reduction intervention. DESIGN AND METHODS: Cost-effectiveness analysis from a societal perspective was undertaken for the randomized controlled trial Supermarket Healthy Eating for Life (SHELf). Female shoppers in Melbourne, Australia were randomized to: (1) skill-building (n = 160); (2) price reductions (n = 161); (3) combined skill-building and price reduction (n = 161); or (4) control group (n = 161). The intervention was implemented for three months followed by a six month follow-up. Costs were measured in 2012 Australian dollars. Fruit and vegetable purchasing and consumption were measured in grams/week. RESULTS: At three months, compared to control participants, price reduction participants increased vegetable purchases by 233 g/week (95% CI 4 to 462, p = 0.046) and fruit purchases by 364 g/week (95% CI 95 to 633, p = 0.008). Participants in the combined group purchased 280 g/week more fruits (95% CI 27 to 533, p = 0.03) than participants in the control group. Increases were not maintained six-month post intervention. No effect was noticed in the skill-building group. Compared to the control group, the price reduction intervention cost an additional A$2.3 per increased serving of vegetables purchased per week or an additional A$3 per increased serving of fruit purchased per week. The combined intervention cost an additional A$12 per increased serving of fruit purchased per week compared to the control group. CONCLUSIONS: A 20% discount on fruits and vegetables was effective in promoting overall fruit and vegetable purchases during the period the discount was active and may be cost-effective. The price discount program gave better value for money than the combined price reduction and skill-building intervention. The SHELf trial is registered with Current Controlled Trials Registration ISRCTN39432901.

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Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

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An unstructured mesh �nite volume discretisation method for simulating di�usion in anisotropic media in two-dimensional space is discussed. This technique is considered as an extension of the fully implicit hybrid control-volume �nite-element method and it retains the local continuity of the ux at the control volume faces. A least squares function recon- struction technique together with a new ux decomposition strategy is used to obtain an accurate ux approximation at the control volume face, ensuring that the overall accuracy of the spatial discretisation maintains second order. This paper highlights that the new technique coincides with the traditional shape function technique when the correction term is neglected and that it signi�cantly increases the accuracy of the previous linear scheme on coarse meshes when applied to media that exhibit very strong to extreme anisotropy ratios. It is concluded that the method can be used on both regular and irregular meshes, and appears independent of the mesh quality.