1,347 research outputs found
Tax Policy and Tax Research in Canada
In a survey of tax reform in recent years, Richard Bird and Michael Smart explore the relationship between tax policy and tax research. They conclude that there have been important examples of apparent influences of research on policy. For instance, they are encouraged that the downward pressure on personal and corporate taxes has certainly been supported, if not initiated, by the increasing evidence of distortions caused by high marginal tax rates. In their view, the adoption of the GST can be explained by the acceptance of the federal government of the economic argument that Canada had to switch to a value-added tax to reduce economic distortions. On the other hand, they are disappointed that the equally convincing economic studies of the damage done by poorly-designed excise, property and payroll taxes do not seem to have had any effect. Consequently, they believe that political economy factors were probably the more dominant explanation of the tax reforms than the simple acceptance of advice from economists. Their conclusion is that if economists want to have a greater influence on policy, they need to pay more attention to the issues that motivate policymakers, including, most notably, distributional issues, and they need to write in a way, and in a forum, that will most likely come to the notice of the policy-makers.Canada, Taxation, Income Tax, Value-Added Tax, Value Added Tax, VAT
SEMIOTIKS: Semantically-Enhanced Information Extraction for Improved Knowledge Superiority
Preliminary Cost Model for Space Telescopes
Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. However, great care is required. Some space telescope cost models, such as those based only on mass, lack sufficient detail to support such analysis and may lead to inaccurate conclusions. Similarly, using ground based telescope models which include the dome cost will also lead to inaccurate conclusions. This paper reviews current and historical models. Then, based on data from 22 different NASA space telescopes, this paper tests those models and presents preliminary analysis of single and multi-variable space telescope cost models
Lithium-Based High Energy Density Flow Batteries
Systems and methods in accordance with embodiments of the invention implement a lithium-based high energy density flow battery. In one embodiment, a lithium-based high energy density flow battery includes a first anodic conductive solution that includes a lithium polyaromatic hydrocarbon complex dissolved in a solvent, a second cathodic conductive solution that includes a cathodic complex dissolved in a solvent, a solid lithium ion conductor disposed so as to separate the first solution from the second solution, such that the first conductive solution, the second conductive solution, and the solid lithium ionic conductor define a circuit, where when the circuit is closed, lithium from the lithium polyaromatic hydrocarbon complex in the first conductive solution dissociates from the lithium polyaromatic hydrocarbon complex, migrates through the solid lithium ionic conductor, and associates with the cathodic complex of the second conductive solution, and a current is generated
Opportunities for Transmission Power Control Protocols in Wireless Sensor Networks
This study investigates the opportunities for transmission power control (TPC) protocols in resource constrained wireless sensor networks (WSNs). The paper begins by creating a generalised model to describe the relationship between transmission power, communication reliability and energy consumption. Applying this model to the performance of state-of-the art radio hardware, the maximum potential energy savings achievable through the implementation of a TPC protocol are identified. From this, previous assumptions about the limited impact of protocols and mechanisms, such as TPC, which seek to reduce the energy consumed by wireless communication activities through targeting the distance dependent term are disproven. This paper concludes by presenting guidelines on the link conditions which offer the greatest opportunities for a TPC protocol
New Class of Flow Batteries for Terrestrial and Aerospace Energy Storage Applications
Future sustainable energy generation technologies such as photovoltaic and wind farms require advanced energy storage systems on a massive scale to make the alternate (green) energy options practical. The daunting requirements of such large-scale energy systems such as long operating and cycle life, safety, and low cost are not adequately met by state-of-the-art energy storage technologies such as vanadium flow cells, lead-acid, and zinc-bromine batteries. Much attention is being paid to redox batteries specifically to the vanadium redox battery (VRB) due to their simplicity, low cost, and good life characteristics compared to other related battery technologies. NASA is currently seeking high-specific- energy and long-cycle-life rechargeable batteries in the 10-to-100-kW range to support future human exploration missions, such as planetary habitats, human rovers, etc. The flow batteries described above are excellent candidates for these applications, as well as other applications that propose to use regenerative fuel cells. A new flow cell technology is proposed based on coupling two novel electrodes in the form of solvated electron systems (SES) between an alkali (or alkaline earth) metal and poly aromatic hydrocarbons (PAH), separated by an ionically conducting separator. The cell reaction involves the formation of such SES with a PAH of high voltage in the cathode, while the alkali (or alkaline earth metal) is reduced from such an MPAH complex in the anode half-cell. During recharge, the reactions are reversed in both electrodes. In other words, the alkali (alkaline earth) metal ion simply shuttles from one M-PAH complex (SES) to another, which are separated by a metal-ion conducting solid or polymer electrolyte separator. As an example, the concept was demonstrated with Li-naphthalene//Li DDQ (DDQ is 2,3-Dichloro-5,6-dicyano- 1,4-benzoquinone) separated by lithium super ion conductor, either ceramic or polymer (solid polymer or gel polymer) electrolytes. The reactants are Li-naphthalene dissolved in tetrahydrofuran (THF) with a lithium salt of 1M LiBF4 (lithium tetra fluoroborate) in the anode compartment, and DDQ again dissolved in THF and also containing 1M LiBF4 salt in the cathode half-cell. The solid electrolyte separator used in the first set of experiments is a ceramic solid electrolyte, available from a commercial source. The open circuit voltage of the cells is close to 3.0 V, as expected from the individual half-cell voltages of Li-naphthalene and Li-DDQ. Upon discharge, the cell shows steady discharge voltage of 2.7 V, which confirms that the electrochemical processes do involve lithium ion shuttling from the anodic compartment to the cathode half-cell. The reversibility or rechargeability is demonstrated by charging the partially discharged cells (i.e., with lithium present in the DDQ half). Once again, a steady voltage close to 3.0 V was observed during charge, indicating that the system is quite reversible. In the subsequent concept-demonstration studies, the ceramic electrolyte has been replaced with a gel polymer electrolyte, e.g., PVDF-HFP (poly vinylene difluoride hexafluoropropene) gel, which has several advantages such as high ionic conductivity (almost comparable to liquid electrolyte and about 2 orders of magnitude better than the ceramic equivalent), lower cost, and possibly higher chemical stability at the anode. In addition, it can be bonded to the electrode by thermal fusion to form membrane electrode assemblies (MEAs), as is done in fuel cells
Comparison of machine learning classifier models for bathing water quality exceedances in UK
The revised Bathing Water Directive (rBWD) (2006/7/EC) of the European Parliament requires monitoring of bathing water quality and, if early-warnings are provided to the public, it is permissible to discount a percentage of exceedance events from the monitoring process. This paper describes the development and implementation of both Decision Tree (DT) and Artificial Neural Network (ANN) based machine learning models for 8 beaches in south-west England, UK, as bases for early warning systems (EWS) and compares their performance for one beach. Weekly bacteria-count samples were gathered by the Environment Agency of England (EA) over a 12-year period from 2000-2011 during the 20-week bathing season and this data is used to calibrate and test the models. Daily sampling data were also collected at 5 of the beaches during the 2012 season to provide more robust validation of the models. As a benchmark, models are also compared with use of simple thresholds of antecedent rainfall to classify water quality exceedances. Evolutionary Algorithm-based optimisation of the ANN models is employed using single-objective approach using area under the Receiver Operating Characteristic (ROC) curve as fitness function. The optimum operating point is established using a weighting factor for the relative importance placed on false positives (passes) and false negatives (exceedances). The models use a number of input factors, including antecedent rainfall for the catchment adjacent to each bathing beach. A possible technique for automating selection of inputs is also discussed.Environment Agency (SW
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