Design of database for automatic example-driven design and assembly of man-made objects

Thesis (S.B.)--Massachusetts Institute of Technology, Department of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (page 18).In this project, we have built a database of models that have been designed such that they can be directly fabricated by a casual user. Each of the models in this database has design specifications up to the screw level, and each component has a direct reference to a commercial part from online retailers such as McMaster-Carr and Home Depot. This database was built with the purpose of assisting a data-driven approach to customizable fabrication. This system allows a casual user to create a 3D model input with rough specifications and receive a list of parts that, when assembled, will create the model specified. Using this system and database, we were able to successfully design and fabricate three pieces of furniture and therefore proved the data-driven method approach to be valid.by J. Keneth Piñera.S.B

Numerical Simulation of Internal Heat Transfer Phenomena Occurring During De-Icing of Aircraft Components

An experimental study to determine the convective heat transfer coefficient from castings made from ice-roughened plates is reported. A corresponding topic, 'Measurements of the Convective Heat Transfer Coefficient from Ice Roughened Surfaces in Parallel and Accelerated Flows,' is presented

Optimum Object Analysis Of Islands Activities On South China Sea By DNB On VIIRS

A data processing and analyzing system was designed and made operational with free software to process the big data over the South China Sea (SCS), which are provided by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (Suomi-NPP) to monitor the light distributions in the night. The VIIRS data are processed from the raw data (level-0) to geophysical data (level-3) using the International Polar Orbiter Processing Package (IPOPP), which are freely available from NASA. The Day Night Band (DNB) of VIIRS is extracted from the level-3 data and is geospatially projected for our region of interest (ROI) on the SCS. For those ingested data, an optimum object analysis in geographic domain was proposed to estimate the reclamation activities on coral reefs in the SCS using GDAL. A pixel base analysis of DNB data is possible to estimate the island activities independently among dredgers, support vessels, or buildings on coral reefs, but not appropriate to analyze the activities for as an integrated system or for the changes in the ROI. Although there is a difficulty to determine the scale of objects on the analysis of DNB data for the reclamation activities, the optimum object scale was empirically determined for different size of coral reefs and was applied for this study. The optimum object analysis determines the reclamation activities with including lights not only from buildings but also dredgers and supporting vessels around coral reefs

Machine-Learning Enhanced Photometric Analysis of the Extremely Bright GRB 210822A

We present analytical and numerical models of the bright long GRB 210822A at $z=1.736$. The intrinsic extreme brightness exhibited in the optical, which is very similar to other bright GRBs (e.g., GRBs 080319B, 130427A, 160625A 190114C, and 221009A), makes GRB 210822A an ideal case for studying the evolution of this particular kind of GRB. We use optical data from the RATIR instrument starting at $T+315.9$ s, with publicly available optical data from other ground-based observatories, as well as X-ray data from the Swift/X-ray Telescope (XRT) and data from the Swift/Ultraviolet/Optical Telescope (UVOT). The temporal profiles and spectral properties during the late stages align consistently with the conventional forward shock model, complemented by a reverse shock element that dominates optical emissions during the initial phases ($T<300$ s). Furthermore, we observe a break at $T=80000$ s that we interpreted as evidence of a jet break, which constrains the opening angle to be about $\theta_\mathrm{j}=(3-5)$ degrees. Finally, we apply a machine-learning technique to model the multi-wavelength light curve of GRB 210822A using the AFTERGLOWPY library. We estimate the angle of sight $\theta_{obs}=(6.4 \pm 0.1) \times 10^{-1}$ degrees, the energy $E_0= (7.9 \pm 1.6)\times 10^{53}$ ergs, the electron index $p=2.54 \pm 0.10$, the thermal energy fraction in electrons $\epsilon_e=(4.63 \pm 0.91) \times 10^{-5}$ and in the magnetic field $\epsilon_B= (8.66 \pm 1.01) \times 10^{-6}$, the efficiency $\chi = 0.89 \pm 0.01$, and the density of the surrounding medium $n_\mathrm{0} = 0.85 \pm 0.01$.Comment: Submitted to MNRAS, 11 pages, 6 figures. Fixed typo

Investigation of orientation effects in films of nitric acid trihydrate

9 p.: gráf.An investigation of orientation effects in films of nitric acid trihydrate (NAT) is presented, based on a systematic study of reflection-absorption infrared spectra of samples of varying thickness. The samples are prepared by vapor deposition on an Al substrate at 90 K and annealing at 175 K to produce crystalline α-NAT films. Spectra were recorded at a grazing angle of 75°, with polarized radiation. The observed spectra are compared with predictions of a classical Fresnel model, in order to test the available optical indices of NAT, which are of great importance for the accurate interpretation of data from remote sensing measurements.Whereas a similar procedure yielded satisfactory results for water ice, it is found that the agreement is not acceptable for NAT crystals. An explanation is suggested in terms of anisotropic or birefringent properties of the crystals, or as due to a preferential alignment of the films. The infrared activity of a peak at ≈ 1140 cm -1, which had previously been associated to changes in the crystal structure upon heating, is here explained in terms of a rearrangement of the polycrystals in the sample.© Royal Society of Chemistry 2004Funded by the Spanish Ministry of Science and Technology, Project REN2000-1557Peer reviewe

Infrared spectra of nitric acid trihydrate (β-NAT): A comparison of available optical constants and implication for the detection of polar stratospheric clouds (PSCs)

The β phase of nitric acid trihydrate (β-NAT) is assumed to be one of the essential components of polar stratospheric clouds (PSC) and may play an important role in ozone chemistry. Infrared spectra of vapour deposited films of β-NAT, have been measured in transmission and in reflection-absorption (RAIR). The spectra have been simulated with the different sets of optical constants available in the literature. The films are found to be optically isotropic. The refractive indices of Toon et al. (1994) give the best global fit to the data, but have low resolution and tend to smooth sharp features. The higher resolution indices of Höpfner et al. (2006) lead to worse ; overall spectral simulations, but can account for the comparatively narrow feature at 820 cm-1 recently identified in field measurements of β-NAT particles. The best compromise is obtained with the >coa> indices of Höpfner et al. Copyright 2006 by the American Geophysical Union.Funded by Project FIS2004-00456 of the Spanish Ministry of Education and has been performed within the framework of the ‘‘Unidad Asociada’’ between IEM (CSIC Madrid) and the Department of Analytical and Physical Chemistry of the University of Jaén (Spain)Peer Reviewe

Hemingway in the 1930s: A Conversation

Transcript of a panel discussion focusing on Hemingway’s life and art in the 1930s. Includes discourse on the Pfeiffer family’s emotional and financial support of the author, his political views, writings for Esquire, and suicide