121 research outputs found

    Some methods of classical mechanics applied to continuous systems

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    Implementing responsibility centre management in a higher educational institution

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    Emerald allows authors to deposit their AAM under the Creative Commons Attribution Non-commercial International Licence 4.0 (CC BY-NC 4.0). To do this, the deposit must clearly state that the AAM is deposited under this licence and that any reuse is allowed in accordance with the terms outlined by the licence. To reuse the AAM for commercial purposes, permission should be sought by contacting [email protected]. For the sake of clarity, commercial usage would be considered as, but not limited to: o Copying or downloading AAMs for further distribution for a fee; o Any use of the AAM in conjunction with advertising; o Any use of the AAM by for promotional purposes by for-profit organisations; o Any use that would confer monetary reward, commercial gain or commercial exploitation. Emerald appreciates that some authors may not wish to use the CC BY-NC licence; in this case, you should deposit the AAM and include the copyright line of the published article. Should you have any questions about our licensing policies, please contact [email protected] ReviewedThe purpose of this study is to examine the design, development, and implementation of responsibility centre management at a mid-sized Canadian university, within the context of decentralized decision making. More specifically our study focused on the design, development and implementation of a revenue and cost allocation process known as transparent activity-based budgeting system (TABBS). The authors conducted this study using a qualitative case study methodology, rooted in grounded theory, as the primary approach to collect and analyze data, and report the findings. Primary data was collected from ten participants using semi-structured interviews. The main takeaways from our research are that (1) such systems take time to design, develop and implement, (2) consultation, communication and information sharing, and model adjustment and refinement are important enabling mechanisms, (3) internal and external events posed significant challenges, (4) although such systems are often designed keeping in mind several intended outcomes there exists the possibility of experiencing some unintended consequences, and (5) the juxtaposition of the above has the potential to negatively or positively impact organizational performance. The research demonstrates that the design, development, and implementation of a complex resource allocation model is an important element of a responsibility centered approach to planning and decision making. It highlights the importance and contribution of enabling mechanisms as well as the challenges that large, complex organizations may confront when introducing change

    One-dimensional relativistic dissipative system with constant force and its quantization

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    For a relativistic particle under a constant force and a linear velocity dissipation force, a constant of motion is found. Problems are shown for getting the Hamiltoninan of this system. Thus, the quantization of this system is carried out through the constant of motion and using the quantization of the velocity variable. The dissipative relativistic quantum bouncer is outlined within this quantization approach.Comment: 11 pages, no figure

    A direct approach to the construction of standard and non-standard Lagrangians for dissipative dynamical systems with variable coefficients

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    We present a direct approach to the construction of Lagrangians for a large class of one-dimensional dynamical systems with a simple dependence (monomial or polynomial) on the velocity. We rederive and generalize some recent results and find Lagrangian formulations which seem to be new. Some of the considered systems (e.g., motions with the friction proportional to the velocity and to the square of the velocity) admit infinite families of different Lagrangian formulations.Comment: 17 page

    Velocity quantization approach of the one-dimensional dissipative harmonic oscillator

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    Given a constant of motion for the one-dimensional harmonic oscillator with linear dissipation in the velocity, the problem to get the Hamiltonian for this system is pointed out, and the quantization up to second order in the perturbation approach is used to determine the modification on the eigenvalues when dissipation is taken into consideration. This quantization is realized using the constant of motion instead of the Hamiltonian.Comment: 10 pages, 2 figure

    The role of plasma-atom and molecule interactions on power \& particle balance during detachment on the MAST Upgrade Super-X divertor

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    First quantitative analysis of the detachment processes in the MAST Upgrade Super-X divertor show an unprecedented impact of plasma-molecular interactions involving molecular ions (likely D2+D_2^+), resulting in strong ion sinks, leading to a reduction of ion target flux. This starts to occur as the ionisation source detaches from the target, leading to a build-up of molecules below the ionisation source who get excited, resulting in Molecular Activated Recombination (MAR) and Dissociation (MAD). The particle sinks in the divertor chamber exceed the ion sources in the middle of the detached operational regime before electron-ion recombination (EIR) starts to occur, demonstrating the strong capabilities for particle exhaust in the Super-X Configuration. MAD is the dominant volumetric neutral atom creation mechanism and results in significant power losses. This, combined with electron-impact excitation preceding ionisation, are the dominant power loss mechanisms in the divertor chamber. As the plasma becomes more deeply detached, EIR starts to occur and electron temperatures below 0.2 eV are achieved. Even at such low electron temperature conditions, MAR is observed to be an important ion sink mechanism, which suggests the presence of highly vibrationally excited molecules in the cold detached regime. The total radiative power loss is consistent with extrapolations of spectroscopic inferences to hydrogenic radiative power losses, which suggests that intrinsic impurity radiation, despite the carbon walls, is minor. These observations are observed in Ohmic L-mode, ELM-free H-mode and type I ELMy H-mode discharges

    Progress in Classical and Quantum Variational Principles

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    We review the development and practical uses of a generalized Maupertuis least action principle in classical mechanics, in which the action is varied under the constraint of fixed mean energy for the trial trajectory. The original Maupertuis (Euler-Lagrange) principle constrains the energy at every point along the trajectory. The generalized Maupertuis principle is equivalent to Hamilton's principle. Reciprocal principles are also derived for both the generalized Maupertuis and the Hamilton principles. The Reciprocal Maupertuis Principle is the classical limit of Schr\"{o}dinger's variational principle of wave mechanics, and is also very useful to solve practical problems in both classical and semiclassical mechanics, in complete analogy with the quantum Rayleigh-Ritz method. Classical, semiclassical and quantum variational calculations are carried out for a number of systems, and the results are compared. Pedagogical as well as research problems are used as examples, which include nonconservative as well as relativistic systems

    The role of plasma–atom and molecule interactions on power & particle balance during detachment on the MAST Upgrade Super-X divertor

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    This paper shows first quantitative analysis of the detachment processes in the MAST Upgrade Super-X divertor (SXD). We identify an unprecedented impact of plasma-molecular interactions involving molecular ions (likely D2+ ), resulting in strong ion sinks (Molecular Activated Recombination—MAR), leading to a reduction of ion target flux. The MAR ion sinks exceed the divertor ion sources before electron-ion recombination (EIR) starts to occur, suggesting that significant ionisation occurs outside of the divertor chamber. In the EIR region, Te≪0.2 eV is observed and MAR remains significant in these deep detached phases. The total ion sink strength demonstrates the capability for particle (ion) exhaust in the Super-X Configuration. Molecular Activated Dissociation is the dominant volumetric neutral atom creation process can lead to an electron cooling of 20% of PSOL . The measured total radiative power losses in the divertor chamber are consistent with inferred hydrogenic radiative power losses. This suggests that intrinsic divertor impurity radiation, despite the carbon walls, is minor in the divertor chamber. This contrasts previous TCV results, which may be associated with enhanced plasma-neutral interactions and reduced chemical erosion in the detached, tightly baffled SXD. The above observations have also been observed in higher heat flux (narrower SOL width) type I ELMy H-mode discharges. This provides evidence that the characterisation in this paper may be general

    The thinning of subcontinental lithosphere: The roles of plume impact and metasomatic weakening

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    Geologically rapid (tens of Myr) partial removal of thick continental lithosphere is evident beneath Precambrian terranes, such as North China Craton, southern Africa, and the North Atlantic Craton,and has been linked with thermomechanical erosion by mantle plumes. We performed numerical experiments with realistic viscosities to test this hypothesis and constrain the most important parameters that influence cratonic lithosphere erosion. Our models indicate that the thermomechanical erosion by a plume impact on typical Archean lithospheric mantle is unlikely to be more effective than long-term erosion from normal plate-mantle interaction. Therefore, unmodified cratonic roots that have been stable for billions of years will not be significantly disrupted by the erosion of a plume event. However, the buoyancy and strength of highly depleted continental roots can be modified by fluid-melt metasomatism, and our models show that this is essential for the thinning of originally stable continental roots. The long-term but punctuated history of metasomatic enrichment beneath ancient continents makes this mode of weakening very likely. The effect of the plume impact is to speed up the erosion significantly and help the removal of the lithospheric root to occur within tens of Myr if affected by metasomatic weakening
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