899 resultados para Alien and Sedition laws, 1798.


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The construction industry, one of the most important ones in the development of a country, generates unavoidable impacts on the environment. The social demand towards greater respect for the environment is a high and general outcry. Therefore, the construction industry needs to reduce the impact it produces. Proper waste management is not enough; we must take a further step in environmental management, where new measures need to be introduced for the prevention at source, such as good practices to promote recycling. Following the amendment of the legal frame applicable to Construction and Demolition Waste (C&D waste), important developments have been incorporated in European and International laws, aiming to promote the culture of reusing and recycling. This change of mindset, that is progressively taking place in society, is allowing for the consideration of C&D waste no longer as an unusable waste, but as a reusable material. The main objective of the work presented in this paper is to enhance C&D waste management systems through the development of preventive measures during the construction process. These measures concern all the agents intervening in the construction process as only the personal implication of all of them can ensure an efficient management of the C&D waste generated. Finally, a model based on preventive measures achieves organizational cohesion between the different stages of the construction process, as well as promoting the conservation of raw materials through the use and waste minimization. All of these in order to achieve a C&D waste management system, whose primary goal is zero waste generation

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In recent decades, full electric and hybrid electric vehicles have emerged as an alternative to conventional cars due to a range of factors, including environmental and economic aspects. These vehicles are the result of considerable efforts to seek ways of reducing the use of fossil fuel for vehicle propulsion. Sophisticated technologies such as hybrid and electric powertrains require careful study and optimization. Mathematical models play a key role at this point. Currently, many advanced mathematical analysis tools, as well as computer applications have been built for vehicle simulation purposes. Given the great interest of hybrid and electric powertrains, along with the increasing importance of reliable computer-based models, the author decided to integrate both aspects in the research purpose of this work. Furthermore, this is one of the first final degree projects held at the ETSII (Higher Technical School of Industrial Engineers) that covers the study of hybrid and electric propulsion systems. The present project is based on MBS3D 2.0, a specialized software for the dynamic simulation of multibody systems developed at the UPM Institute of Automobile Research (INSIA). Automobiles are a clear example of complex multibody systems, which are present in nearly every field of engineering. The work presented here benefits from the availability of MBS3D software. This program has proven to be a very efficient tool, with a highly developed underlying mathematical formulation. On this basis, the focus of this project is the extension of MBS3D features in order to be able to perform dynamic simulations of hybrid and electric vehicle models. This requires the joint simulation of the mechanical model of the vehicle, together with the model of the hybrid or electric powertrain. These sub-models belong to completely different physical domains. In fact the powertrain consists of energy storage systems, electrical machines and power electronics, connected to purely mechanical components (wheels, suspension, transmission, clutch…). The challenge today is to create a global vehicle model that is valid for computer simulation. Therefore, the main goal of this project is to apply co-simulation methodologies to a comprehensive model of an electric vehicle, where sub-models from different areas of engineering are coupled. The created electric vehicle (EV) model consists of a separately excited DC electric motor, a Li-ion battery pack, a DC/DC chopper converter and a multibody vehicle model. Co-simulation techniques allow car designers to simulate complex vehicle architectures and behaviors, which are usually difficult to implement in a real environment due to safety and/or economic reasons. In addition, multi-domain computational models help to detect the effects of different driving patterns and parameters and improve the models in a fast and effective way. Automotive designers can greatly benefit from a multidisciplinary approach of new hybrid and electric vehicles. In this case, the global electric vehicle model includes an electrical subsystem and a mechanical subsystem. The electrical subsystem consists of three basic components: electric motor, battery pack and power converter. A modular representation is used for building the dynamic model of the vehicle drivetrain. This means that every component of the drivetrain (submodule) is modeled separately and has its own general dynamic model, with clearly defined inputs and outputs. Then, all the particular submodules are assembled according to the drivetrain configuration and, in this way, the power flow across the components is completely determined. Dynamic models of electrical components are often based on equivalent circuits, where Kirchhoff’s voltage and current laws are applied to draw the algebraic and differential equations. Here, Randles circuit is used for dynamic modeling of the battery and the electric motor is modeled through the analysis of the equivalent circuit of a separately excited DC motor, where the power converter is included. The mechanical subsystem is defined by MBS3D equations. These equations consider the position, velocity and acceleration of all the bodies comprising the vehicle multibody system. MBS3D 2.0 is entirely written in MATLAB and the structure of the program has been thoroughly studied and understood by the author. MBS3D software is adapted according to the requirements of the applied co-simulation method. Some of the core functions are modified, such as integrator and graphics, and several auxiliary functions are added in order to compute the mathematical model of the electrical components. By coupling and co-simulating both subsystems, it is possible to evaluate the dynamic interaction among all the components of the drivetrain. ‘Tight-coupling’ method is used to cosimulate the sub-models. This approach integrates all subsystems simultaneously and the results of the integration are exchanged by function-call. This means that the integration is done jointly for the mechanical and the electrical subsystem, under a single integrator and then, the speed of integration is determined by the slower subsystem. Simulations are then used to show the performance of the developed EV model. However, this project focuses more on the validation of the computational and mathematical tool for electric and hybrid vehicle simulation. For this purpose, a detailed study and comparison of different integrators within the MATLAB environment is done. Consequently, the main efforts are directed towards the implementation of co-simulation techniques in MBS3D software. In this regard, it is not intended to create an extremely precise EV model in terms of real vehicle performance, although an acceptable level of accuracy is achieved. The gap between the EV model and the real system is filled, in a way, by introducing the gas and brake pedals input, which reflects the actual driver behavior. This input is included directly in the differential equations of the model, and determines the amount of current provided to the electric motor. For a separately excited DC motor, the rotor current is proportional to the traction torque delivered to the car wheels. Therefore, as it occurs in the case of real vehicle models, the propulsion torque in the mathematical model is controlled through acceleration and brake pedal commands. The designed transmission system also includes a reduction gear that adapts the torque coming for the motor drive and transfers it. The main contribution of this project is, therefore, the implementation of a new calculation path for the wheel torques, based on performance characteristics and outputs of the electric powertrain model. Originally, the wheel traction and braking torques were input to MBS3D through a vector directly computed by the user in a MATLAB script. Now, they are calculated as a function of the motor current which, in turn, depends on the current provided by the battery pack across the DC/DC chopper converter. The motor and battery currents and voltages are the solutions of the electrical ODE (Ordinary Differential Equation) system coupled to the multibody system. Simultaneously, the outputs of MBS3D model are the position, velocity and acceleration of the vehicle at all times. The motor shaft speed is computed from the output vehicle speed considering the wheel radius, the gear reduction ratio and the transmission efficiency. This motor shaft speed, somehow available from MBS3D model, is then introduced in the differential equations corresponding to the electrical subsystem. In this way, MBS3D and the electrical powertrain model are interconnected and both subsystems exchange values resulting as expected with tight-coupling approach.When programming mathematical models of complex systems, code optimization is a key step in the process. A way to improve the overall performance of the integration, making use of C/C++ as an alternative programming language, is described and implemented. Although this entails a higher computational burden, it leads to important advantages regarding cosimulation speed and stability. In order to do this, it is necessary to integrate MATLAB with another integrated development environment (IDE), where C/C++ code can be generated and executed. In this project, C/C++ files are programmed in Microsoft Visual Studio and the interface between both IDEs is created by building C/C++ MEX file functions. These programs contain functions or subroutines that can be dynamically linked and executed from MATLAB. This process achieves reductions in simulation time up to two orders of magnitude. The tests performed with different integrators, also reveal the stiff character of the differential equations corresponding to the electrical subsystem, and allow the improvement of the cosimulation process. When varying the parameters of the integration and/or the initial conditions of the problem, the solutions of the system of equations show better dynamic response and stability, depending on the integrator used. Several integrators, with variable and non-variable step-size, and for stiff and non-stiff problems are applied to the coupled ODE system. Then, the results are analyzed, compared and discussed. From all the above, the project can be divided into four main parts: 1. Creation of the equation-based electric vehicle model; 2. Programming, simulation and adjustment of the electric vehicle model; 3. Application of co-simulation methodologies to MBS3D and the electric powertrain subsystem; and 4. Code optimization and study of different integrators. Additionally, in order to deeply understand the context of the project, the first chapters include an introduction to basic vehicle dynamics, current classification of hybrid and electric vehicles and an explanation of the involved technologies such as brake energy regeneration, electric and non-electric propulsion systems for EVs and HEVs (hybrid electric vehicles) and their control strategies. Later, the problem of dynamic modeling of hybrid and electric vehicles is discussed. The integrated development environment and the simulation tool are also briefly described. The core chapters include an explanation of the major co-simulation methodologies and how they have been programmed and applied to the electric powertrain model together with the multibody system dynamic model. Finally, the last chapters summarize the main results and conclusions of the project and propose further research topics. In conclusion, co-simulation methodologies are applicable within the integrated development environments MATLAB and Visual Studio, and the simulation tool MBS3D 2.0, where equation-based models of multidisciplinary subsystems, consisting of mechanical and electrical components, are coupled and integrated in a very efficient way.

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The idea of a conservation easement – restrictions on the development and use of land designed to protect the land’s conservation or historic values – can be relatively easily understood. More significant and more challenging is the complex body of state and federal laws that shapes the creation, funding, tax treatment, enforcement, modification, and termination of conservation easements. The explosion in the number of conservation easements over the past four decades has made them one of the most popular land protection mechanisms in the United States. The National Conservation Easement Database estimates that the total number of acres encumbered by conservation easements exceeds 40 million.Because conservation easements are both novel and ubiquitous, understanding how they actual work is essential for practicing lawyers, policymakers, land trust professionals, and students of conservation. This article provides a “quick tour” through some of the most important aspects of the developing mosaic of conservation easement law. It gives the reader a sense of the complex inter-jurisdictional dynamics that shape conservation transactions and disputes about conservation easements. Professors of property law, environmental law, tax law, and environmental studies who wish to cover conservation easements in the context of a more general course can use the article to provide their students with a broad but comprehensive overview of the relevant legal and policy issues.

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The objective of this paper is to provide an analysis of the potential and obstacles to the development of geothermal energy resources in Colorado. Geothermal energy is the only renewable resource that can provide base-load electricity. While Colorado has significant geothermal energy potential, there are no such power plants. Layers of federal and state laws and regulations represent one barrier to further geothermal development. Transmission constraints represent another major barrier. High exploration and construction costs along with high-risk profiles for geothermal projects form another major barrier. Perceived barriers such as misunderstanding the impacts, risks, and benefits of geothermal energy hinder further development. Recommendations are provided to help overcome these obstacles.

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Handwritten order to John Sale to pay scholarship funds to Levi Frisbie for use by his son, signed by David Tilden, and James Morrill.

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Handwritten order to John Sale to pay scholarship funds to Timothy Alden for use by his son signed by John Clarke, David Tilden, and James Morrill.

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Fragment of a leaf with handwritten entries made by Caleb Gannet, the College Steward, for hay weighing hay at the College Farm between 1797 and January 20, 1798.

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One octavo-sized leaf containing handwritten questions in the hand of Professor Pearson regarding the taxation of real estate in Cambridge. A note on the document verso: "Allen 2nd June 11th 1798" indicates Pearson used a student's assignment paper and the date suggests the queries may have been created in preparation for the June 20, 1798 meeting with the Committee of the Town of Cambridge.

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Three printed quarter bills for Loammi Baldwin dated February 22, 1798, May 24, 1798, and November 29, 1798.

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This collection contains approximately twenty-three handwritten lecture summaries on six leaves made by Harvard undergraduate Benjamin Peirce between September 1797 and November 22, 1798. The summaries generally provide a few sentences describing the topic covered and primarily pertain to lectures on English grammar delivered by Eliphalet Pearson, the Hollis Professor of Hebrew and other Oriental Languages. There are also summaries for single lectures by David Tappan, the Hollis Professor Divinity; Samuel Webber, the Hollis Professor of Mathematics and Natural Philosophy; and John Snelling Popkin, the Greek Tutor from 1795 to 1798, and later the Eliot Professor of Greek Literature. There is also an undated summary of a lecture by Benjamin Waterhouse, the Hersey Professor of Theory and Practice of Physic.

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Official discourse in Singapore on social cohesion is often framed along the broad parameters of achieving racial and religious harmony. Many policies – formal and informal – and several laws evolved to manage these two aspects of society. Yet, as Singapore developed and with a much more complex socioeconomic environment both domestically and externally, there is perhaps a need to re-look the discourse and framework for discussing social cohesion. This paper takes a critical look at how the issue of social cohesion is framed in academic literature and policy discussions in Europe and the OECD, and tries to develop a broader analytical framework that could be useful in the Singapore context as it struggles with the multiple fault lines in society (beyond race and religion) that have emerged in the last decade or so.

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Following the financial crisis that commenced in 2008, the relationship between migration and social benefits has become increasingly contested in a number of large EU member states. The Eastern expansion of the EU in 2004 and 2007 has added a new dimension to the relationship. Concerns have spread across a number of member states about the 'costs' and 'financial burdens' of migration and intra-EU mobility and there have been calls for restrictions of existing EU rights and freedoms in the areas of EU free movement, social security coordination, asylum and migration laws.

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This paper focuses on situations in which a person is said never to have had the nationality of a country, even though (s)he assumed (and in many cases the authorities of the country concerned shared that assumption) that (s)he possessed that nationality. Contrary to situations of loss of nationality, where something is taken away that had existed, quasi-loss involves situations in which nationality was never acquired. This contribution seeks to examine whether a person should under certain circumstances be protected against quasi-loss of nationality. In order to do so, the paper first maps out situations of quasi-loss in EU member states, describing typical cases in which a person never acquired the nationality of the country, although (s)he was at some time considered as a national. Drawing on this taxonomy, the paper attempts to uncover whether national, European and international laws offer some protection, and if yes, to which extent, for situations of quasi-loss. It concludes with outlining best practices which Member States should comply with in handling such situations.

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Latest issue consulted: 1925.

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Latest issue consulted: 88th (1993)