1,411 research outputs found
Results of phase one of land use information Delphi study
The Land Use Management Information System (LUMIS) is being developed for the city portion of the Santa Monica mountains. LUMIS incorporates data developed from maps and aerial photos as well as traditional land based data associated with routine city and county record keeping activities and traditional census data. To achieve the merging of natural resource data with governmental data LUMIS is being designed in accordance with restrictions associated with two other land use information systems currently being constructed by Los Angeles city staff. The two city systems are LUPAMS (Land Use Planning and Management System) which is based on data recorded by the County Assessor's office for each individual parcel of land in the city, and Geo-BEDS, a geographically based environmental data system
The availability of local aerial photography in southern California
Some of the major photography and photogrammetric suppliers and users located in Southern California are listed. Recent trends in aerial photographic coverage of the Los Angeles basin area are also noted, as well as the uses of that imagery
LUMIS Interactive graphics operating instructions and system specifications
The LUMIS program has designed an integrated geographic information system to assist program managers and planning groups in metropolitan regions. Described is the system designed to interactively interrogate a data base, display graphically a portion of the region enclosed in the data base, and perform cross tabulations of variables within each city block, block group, or census tract. The system is designed to interface with U. S. Census DIME file technology, but can accept alternative districting conventions. The system is described on three levels: (1) introduction to the systems's concept and potential applications; (2) the method of operating the system on an interactive terminal; and (3) a detailed system specification for computer facility personnel
An automatic deep learning approach for coronary artery calcium segmentation
Coronary artery calcium (CAC) is a significant marker of atherosclerosis and
cardiovascular events. In this work we present a system for the automatic
quantification of calcium score in ECG-triggered non-contrast enhanced cardiac
computed tomography (CT) images. The proposed system uses a supervised deep
learning algorithm, i.e. convolutional neural network (CNN) for the
segmentation and classification of candidate lesions as coronary or not,
previously extracted in the region of the heart using a cardiac atlas. We
trained our network with 45 CT volumes; 18 volumes were used to validate the
model and 56 to test it. Individual lesions were detected with a sensitivity of
91.24%, a specificity of 95.37% and a positive predicted value (PPV) of 90.5%;
comparing calcium score obtained by the system and calcium score manually
evaluated by an expert operator, a Pearson coefficient of 0.983 was obtained. A
high agreement (Cohen's k = 0.879) between manual and automatic risk prediction
was also observed. These results demonstrated that convolutional neural
networks can be effectively applied for the automatic segmentation and
classification of coronary calcifications
Temperature and Emission-Measure Profiles Along Long-Lived Solar Coronal Loops Observed with TRACE
We report an initial study of temperature and emission measure distributions
along four steady loops observed with the Transition Region and Coronal
Explorer (TRACE) at the limb of the Sun. The temperature diagnostic is the
filter ratio of the extreme-ultraviolet 171-angstrom and 195-angstrom
passbands. The emission measure diagnostic is the count rate in the
171-angstrom passband. We find essentially no temperature variation along the
loops. We compare the observed loop structure with theoretical isothermal and
nonisothermal static loop structure.Comment: 10 pages, 3 postscript figures (LaTeX, uses aaspp4.sty). Accepted by
ApJ Letter
Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
New X-ray observatories (Chandra and XMM-Newton) are providing a wealth of
high-resolution X-ray spectra in which hydrogen- and helium-like ions are
usually strong features. We present results from a new collisional-radiative
plasma code, the Astrophysical Plasma Emission Code (APEC), which uses atomic
data in the companion Astrophysical Plasma Emission Database (APED) to
calculate spectral models for hot plasmas. APED contains the requisite atomic
data such as collisional and radiative rates, recombination cross sections,
dielectronic recombination rates, and satellite line wavelengths. We compare
the APEC results to other plasma codes for hydrogen- and helium-like
diagnostics, and test the sensitivity of our results to the number of levels
included in the models. We find that dielectronic recombination with
hydrogen-like ions into high (n=6-10) principal quantum numbers affects some
helium-like line ratios from low-lying (n=2) transitions.Comment: 5 pages, 6 figures, accepted by ApJ Letter
Superflares on Ordinary Solar-Type Stars
Short duration flares are well known to occur on cool main-sequence stars as
well as on many types of `exotic' stars. Ordinary main-sequence stars are
usually pictured as being static on time scales of millions or billions of
years. Our sun has occasional flares involving up to ergs which
produce optical brightenings too small in amplitude to be detected in
disk-integrated brightness. However, we identify nine cases of superflares
involving to ergs on normal solar-type stars. That is,
these stars are on or near the main-sequence, are of spectral class from F8 to
G8, are single (or in very wide binaries), are not rapid rotators, and are not
exceedingly young in age. This class of stars includes many those recently
discovered to have planets as well as our own Sun, and the consequences for any
life on surrounding planets could be profound. For the case of the Sun,
historical records suggest that no superflares have occurred in the last two
millennia.Comment: 16 pages, accepted for publication in Ap
L’influenza dell’attaccamento e della sensibilità diadica genitorialesullo sviluppo psicomotorio del bambino nato pretermine
Lo scopo di questa ricerca è studiare i precursori dell’attaccamento e la sensibilità diadica genitoriale nelle famiglie con bambino nato pretermine.
Sono state considerate 110 famiglie delle quali 55 con figli nati pretermine ( peso alla nascita < 1500 gr.) per un totale di 330 soggetti valutati durante i primi sei mesi di età corretta del bambino. Le diadi madre-bambino e padre-bambino sono state sottoposte al CARE-Index, una procedura videoregistrata per la valutazione dei precursori dell’attaccamento; ad entrambi i genitori sono stati somministrati CES-D, per la valutazione della depressione e STAI Y-2, per la valutazione dell’ansia di tratto. Lo sviluppo psicomotorio dei neonati è stato valutato tramite le scale Bayley.
Rispetto ai controlli, nelle madri dei bambini pretermine sono stati evidenziati bassi punteggi di Sensibilità Diadica al CARE-Index (p=.025) ed elevati livelli di ansia (p=.026). Nei padri sono stati riscontrati bassi punteggi di Sensibilità Diadica (p=.004) e alti livelli di sintomi depressivi (p=.003). Nelle famiglie pretermine i precursori dell’attaccamento sono più frequentemente di tipo insicuro nelle madri (p=.000) e nei padri (p=.000), mentre nei neonati solo nell’interazione con la madre (p=012). Questi fattori sono risultati associati a minori punteggi alle scale Bayley (p=.000). Nelle madri dei neonati pretermine si riscontrano frequenti difficoltà con la famiglia di origine, nei padri una percezione negativa del proprio bambino e una maggiore insoddisfazione per l’assistenza ricevuta.
Questi risultati evidenziano che il 40% delle madri e il 75% dei padri dei bambini nati pretermine rientra nella fascia ad alto rischio del CARE-Index (che richiede un trattamento psicologico e/o farmacologico). In tali casi, la scarsa sensibilità diadica, i precursori di attaccamento insicuro e le difficoltà psicologiche dei genitori sembrano influenzare lo sviluppo psicomotorio del bambino
EUV emission lines and diagnostics observed with Hinode/EIS
Quiet Sun and active region spectra from the Hinode/EIS instrument are
presented, and the strongest lines from different temperature regions
discussed. A list of emission lines recommended to be included in EIS
observation studies is presented based on analysis of blending and diagnostic
potential using the CHIANTI atomic database. In addition we identify the most
useful density diagnostics from the ions covered by EIS.Comment: 14 pages, 3 figures, submitted to PASJ Hinode first results issu
A solar active region loop compared with a 2D MHD model
We analyzed a coronal loop observed with the Normal Incidence Spectrometer
(NIS), which is part of the Coronal Diagnostic Spectrometer (CDS) on board the
Solar and Heliospheric Observatory (SOHO). The measured Doppler shifts and
proper motions along the selected loop strongly indicate unidirectional flows.
Analysing the Emission Measure Curves of the observed spectral lines, we
estimated that the temperature along the loop was about 380000 K. We adapted a
solution of the ideal MHD steady equations to our set of measurements. The
derived energy balance along the loop, as well as the advantages/disadvantages
of this MHD model for understanding the characteristics of solar coronal loops
are discussed.Comment: A&A in press, 10 pages, 6 figure
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