3,826 research outputs found
MATLAB code for HiFi-NL-SIM
No full textMATLAB source code, user manual and test data of HiFi-NL-SIM softwar
Routing optimization with time windows under uncertainty
No full textWe study an a priori Traveling Salesman Problem with Time Windows (tsptw) in which the travel times along the arcs are uncertain and the goal is to determine within a budget constraint, a route for the service vehicle in order to arrive at the customers’ locations within their stipulated time windows as well as possible. In particular, service at customer’s location cannot commence before the beginning of the time window and any arrival after the end of the time window is considered late and constitutes to poor customer service. In articulating the service level of the tsptw under uncertainty, we propose a new decision criterion, called the essential riskiness index, which has the computationally attractive feature of convexity that enables us to formulate and solve the problem more effectively. As a decision criterion for articulating service levels, it takes into account both the probability of lateness and its magnitude, and can be applied in contexts where either the distributional information of the uncertain travel times is fully or partially known. We propose a new formulation for the tsptw, where we explicitly express the service starting time at each customer’s location as a convex piecewise affine function of the travel times, which would enable us to obtain the tractable formulation of the corresponding distributionally robust problem. We also show how to optimize the essential riskiness index via Benders decomposition and present cases where we can obtain closed-form solutions to the subproblems. We also illustrate in our numerical studies that this approach scales well with the number of samples used for the sample average approximation. The approach can be extended to a more general setting including Vehicle Routing Problem with Time Windows with uncertain travel times and customers’ demands
An analytical back gate bias dependent threshold voltage model for SiGe-channel ultra-thin SOI PMOS devices
No full textA novel model of learning in design
No full textLearning in design is a phenomenon that has been observed in design practice by many researchers. The observation that designers learn is supported by protocol studies in design that experienced designers can reach satisfactory design solutions more effectively than novice/naive designers. That there was no comprehensive model or theory of learning in design to explain the phenomenon was identified by Sim. Hence a need was raised to develop a comprehensive model of learning in design that can describe the phenomenon and therefore serve as a basis to develop effective and efficient design support system(s)
Efficient Jacobian-Based Inverse Kinematics With Sim-to-Real Transfer of Soft Robots by Learning
No full textThis article presents an efficient learning-based method to solve the <italic>inverse kinematic</italic> (IK) problem on soft robots with highly nonlinear deformation. The major challenge of efficiently computing IK for such robots is due to the lack of analytical formulation for either forward or inverse kinematics. To address this challenge, we employ neural networks to learn both the mapping function of forward kinematics and also the Jacobian of this function. As a result, Jacobian-based iteration can be applied to solve the IK problem. A sim-to-real training transfer strategy is conducted to make this approach more practical. We first generate a large number of samples in a simulation environment for learning both the kinematic and the Jacobian networks of a soft robot design. Thereafter, a sim-to-real layer of differentiable neurons is employed to map the results of simulation to the physical hardware, where this sim-to-real layer can be learned from a very limited number of training samples generated on the hardware.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Materials and ManufacturingMechatronic Desig
Alpha particle spectroscopy using FNTD and SIM super-resolution microscopy
No full textStructured illumination microscopy (SIM) for the imaging of alpha particle tracks in fluorescent nuclear track detectors (FNTD) was evaluated and compared to confocal laser scanning microscopy (CLSM). FNTDs were irradiated with an external alpha source and imaged using both methodologies. SIM imaging resulted in improved resolution, without increase in scan time. Alpha particle energy estimation based on the track length, direction and intensity produced results in good agreement with the expected alpha particle energy distribution. A pronounced difference was seen in the spatial scattering of alpha particles in the detectors, where SIM showed an almost 50% reduction compared to CLSM. The improved resolution of SIM allows for more detailed studies of the tracks induced by ionising particles. The combination of SIM and FNTDs for alpha radiation paves the way for affordable and fast alpha spectroscopy and dosimetry. Journal compilatio
A simple disc wind model for broad absorption line quasars
No full textApproximately 20 per cent of quasi-stellar objects (QSOs) exhibit broad, blue-shifted absorption lines in their ultraviolet spectra. Such features provide clear evidence for significant outflows from these systems, most likely in the form of accretion disc winds. These winds may represent the ‘quasar’ mode of feedback that is often invoked in galaxy formation/evolution models, and they are also key to unification scenarios for active galactic nuclei (AGN) and QSOs. To test these ideas, we construct a simple benchmark model of an equatorial, biconical accretion disc wind in a QSO and use a Monte Carlo ionization/radiative transfer code to calculate the ultraviolet spectra as a function of viewing angle. We find that for plausible outflow parameters, sightlines looking directly into the wind cone do produce broad, blue-shifted absorption features in the transitions typically seen in broad absorption line (BAL) QSOs. However, our benchmark model is intrinsically X-ray weak in order to prevent overionization of the outflow, and the wind does not yet produce collisionally excited line emission at the level observed in non-BAL QSOs. As a first step towards addressing these shortcomings, we discuss the sensitivity of our results to changes in the assumed X-ray luminosity and mass-loss rate, Ṁwind. In the context of our adopted geometry, Ṁwind ∼ Ṁacc is required in order to produce significant BAL features. The kinetic luminosity and momentum carried by such outflows would be sufficient to provide significant feedback
Connecticut State Innovation Model (SIM); Proposed framework--revised 4/30/19
No full text1 online resource (32 pages) : color illustrationsFinal version; "This report was prepared by Health Management Associates (HMA), a leading independent national research and consulting firm"--Page 3; "The project described was supported by Funding Opportunity Number CMS-1G1CMS331630-02-00 from the U.S. Department of Health & Human Services, Centers for Medicare & Medicaid Services."; "Approved June 2019."; Includes bibliographical reference
Old Brisbane Botanic Gardens: Conservation Plan Review 2005, Report of Stage 1 Heritage Significance and Conservation Policies
No full textReport for City Design, for Environment and Parks, within the Brisbane City Council.\ud
\ud
Context of this Project\ud
\ud
A Conservation Study for the Old Brisbane Botanic Gardens,\ud
formerly called the Brisbane City Botanic Gardens, was finalised in\ud
1995 and prepared by Jeannie Sim for the Landscape Section of\ud
Brisbane City Council, the same author of the present report. This\ud
unpublished report was the first conservation plan prepared for the\ud
place and it was recommended that it be reviewed in five years\ud
time. That time has arrived finally with the preparation of the 2005\ud
Review. The present project was commissioned by City Design on\ud
behalf of Environment and Parks Section of Brisbane City Council.\ud
\ud
The author has purposely chosen to call the study site the 'Old\ud
Brisbane Botanic Gardens' (OBBG) to differentiate it from the\ud
Brisbane Botanic Gardens, Mt. Coot-tha (BBG-MC), and to\ud
maintain the claim for this original garden to remain as a botanic\ud
garden for Brisbane. This name immediately brings to mind an\ud
association with history, as in the precedent set by the naming of\ud
the nearby 'Old Government House' at Gardens Point
Post-disaster school relocation : a case study of Chinese students’ adjustment after the Wenchuan earthquake
No full textAuthor name used in this publication: Ng, Guat Tin.Author name used in this publication: Sim, Timothy.Accepted ManuscriptPublishedGreen (AAM
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