276 research outputs found
IDENTIFYING THE INFORMATION-SEEKING BEHAVIORS OF STUDENTS, THE EXPECTATIONS OF FACULTY, AND THE ROLE OF LIBRARIANS IN WRITING ASSIGNMENTS THAT REQUIRE STUDENTS TO USE INFORMATION SOURCES IN SELECTED PENNSYLVANIA COMMUNITY COLLEGES: A MODEL FOR INSTRUCTION
The intent of this exploratory study is to identify the information-seeking behaviors used by community college students when using information resources to complete a writing assignment, the expectations that faculty have in regard to that writing assignment and the role librarians can play in that process through information literacy instruction. The population identified for this study was the population of community college students in Pennsylvania involved with their first writing assignment and who may or may not have had exposure to an information literacy instruction class. Pennsylvania community colleges were chosen because Pennsylvania does not have a statewide community college system. Based on analysis of findings from the interactions among students, faculty and librarians, the researcher outlines some best practices for community colleges in Pennsylvania to adopt and proposes a model for instruction based on those practices. The best practices include: 1) faculty and librarian collaboration to address advanced information literacy instruction needs of students to complete the writing assignment successfully, 2) allocation of more time by faculty for librarians to instruct students on advanced searching skills and citation formats, 3) development and adoption by community college librarians of a set of standardized learning objectives based on performance indicators outlined by the Association of College and Research Libraries to ensure that all students receive the skills necessary to provide a strong foundation for using library resources
Identification of Galaxy-Galaxy Strong Lens Candidates in the DECam Local Volume Exploration Survey Using Machine Learning
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMWe perform a search for galaxy-galaxy strong lens systems using a convolutional neural network (CNN) applied to imaging data from the first public data release of the DECam Local Volume Exploration Survey, which contains 1/4520 million astronomical sources covering 1/44000 deg2 of the southern sky to a 5σ point-source depth of g = 24.3, r = 23.9, i = 23.3, and z = 22.8 mag. Following the methodology of similar searches using Dark Energy Camera data, we apply color and magnitude cuts to select a catalog of 1/411 million extended astronomical sources. After scoring with our CNN, the highest-scoring 50,000 images were visually inspected and assigned a score on a scale from 0 (not a lens) to 3 (very probable lens). We present a list of 581 strong lens candidates, 562 of which are previously unreported. We categorize our candidates using their human-assigned scores, resulting in 55 Grade A candidates, 149 Grade B candidates, and 377 Grade C candidates. We additionally highlight eight potential quadruply lensed quasars from this sample. Due to the location of our search footprint in the northern Galactic cap (b > 10 deg) and southern celestial hemisphere (decl. < 0 deg), our candidate list has little overlap with other existing ground-based searches. Where our search footprint does overlap with other searches, we find a significant number of high-quality candidates that were previously unidentified, indicating a degree of orthogonality in our methodology. We report properties of our candidates including apparent magnitude and Einstein radius estimated from the image separation
Recommended from our members
An analysis and evaluation of the WeFold collaborative for protein structure prediction and its pipelines in CASP11 and CASP12
Every two years groups worldwide participate in the Critical Assessment of Protein Structure Prediction (CASP) experiment to blindly test the strengths and weaknesses of their computational methods. CASP has significantly advanced the field but many hurdles still remain, which may require new ideas and collaborations. In 2012 a web-based effort called WeFold, was initiated to promote collaboration within the CASP community and attract researchers from other fields to contribute new ideas to CASP. Members of the WeFold coopetition (cooperation and competition) participated in CASP as individual teams, but also shared components of their methods to create hybrid pipelines and actively contributed to this effort. We assert that the scale and diversity of integrative prediction pipelines could not have been achieved by any individual lab or even by any collaboration among a few partners. The models contributed by the participating groups and generated by the pipelines are publicly available at the WeFold website providing a wealth of data that remains to be tapped. Here, we analyze the results of the 2014 and 2016 pipelines showing improvements according to the CASP assessment as well as areas that require further adjustments and research
Research of Microstructure of Molybden Doped Weldings of Oil and Gas Pipelines
Still existing scientific, technical and technological developments to improve the quality of welded joints of metal
pipe structures contain contradictions and uncertainty about the effects of alloying elements, such as molybdenum, mechanical and visco plastic properties, as well as metallographic component joints. All this indicates the need for a systematic study of these problems for the development of rational metallurgical and technological measures to significantly improve the technological and corrosion-mechanical properties of weld metal. Metallographic studies, using laboratory equipment with high identifying ability, found that the doping of weld metal with molybdenum in the amount of 0.2-0.4% causes fragmentation of ferrite-pearlite structure, including carbides Mn and Fe, and also reduces the number and size of non-metallic inclusions – sulfides, oxides and silicates. Moreover, non-metallic inclusions have a dispersed appearance, which promotes plasticization of the structure, which directly increases the viscous-plastic characteristics and resistance of the metal joints to crack formation. Based on the results of metallographic research, the optimum content in the weld metal of the alloyed element – molybdenum, which is 0.2-0.4%, is determined
COOL-LAMPS. IV. A Sample of Bright Strongly Lensed Galaxies at 3 < z < 4
We report the discovery of five bright, strong gravitationally lensed galaxies at 3 < z < 4: COOL J0101+2055 (z = 3.459), COOL J0104−0757 (z = 3.480), COOL J0145+1018 (z = 3.310), COOL J0516−2208 (z = 3.549), and COOL J1356+0339 (z = 3.753). These galaxies have magnitudes of rAB, zAB < 21.81 mag and are lensed by galaxy clusters at 0.26 < z < 1. This sample nearly doubles the number of known bright lensed galaxies with extended arcs at 3 < z < 4. We characterize the lensed galaxies using ground-based grz/giy imaging and optical spectroscopy. We report model-based magnitudes and derive stellar masses, dust content, and star formation rates via stellar population synthesis modeling. Building lens models based on ground-based imaging, we estimate source magnifications ranging from ∼29 to ∼180. Combining these analyses, we derive demagnified stellar masses in the range and star formation rates in the youngest age bin in the range , placing the sample galaxies on the massive end of the star-forming main sequence in this redshift interval. In addition, three of the five galaxies have strong Lyα emissions, offering unique opportunities to study Lyα emitters at high redshift in future work
How echinoccocosis affects potential cancer markers in plasma: galectin-3, sN-cadherin and sE-cadherin? a preliminary report
The DELVE Quadruple Quasar Search I. A Lensed Low Luminosity AGN
A quadruply lensed source, J125856.3-031944, has been discovered using the
DELVE survey and WISE W1 - W2 colors. Followup direct imaging carried out with
the MPIA 2.2 m and the Baade 6.5 m telescopes is analyzed, as is spectroscopy
from the 2.5 m Nordic Optical Telescope. The lensed image configuration is
kite-like, with the faintest image 2 magnitudes fainter than the other three.
Redward of 6000 AA that image is badly blended with the lensing galaxy, which
is elongated along the symmetry axis of the kite. Magellan direct imaging
carried out in Sloan g permits better deblending. As the lensed image
configuration is nearly circular, simple models give individual magnifications
of at least 25 for the 3 brighter images. The source's narrow emission lines
and low intrinsic luminosity qualify it as a type 2 AGN.Comment: 8 pages, 5 figures, submitted to AJ, comments welcom
COOL-LAMPS. VII. Quantifying Strong-lens Scaling Relations with 177 Cluster-scale Gravitational Lenses in DECaLS
We compute parametric measurements of the Einstein-radius-enclosed total mass
for 177 cluster-scale strong gravitational lenses identified by the ChicagO
Optically-selected Lenses Located At the Margins of Public Surveys (COOL-LAMPS)
collaboration with lens redshifts ranging from using only two measured parameters in each lensing system: the Einstein
radius, and the brightest-cluster-galaxy (BCG) redshift. We then constrain the
Einstein-radius-enclosed luminosity and stellar mass by fitting parametric
spectral energy distributions (SEDs) with aperture photometry from the Dark
Energy Camera Legacy Survey (DECaLS) in the , , and -band Dark Energy
Camera (DECam) filters. We find that the BCG redshift, enclosed total mass, and
enclosed luminosity are strongly correlated and well described by a planar
relationship in 3D space. We also find that the enclosed total mass and stellar
mass are correlated with a logarithmic slope of , and the
enclosed total mass and stellar-to-total mass fraction are correlated with a
logarithmic slope of . The correlations described here can be
used to validate strong lensing candidates in upcoming imaging surveys -- such
as Rubin/Legacy Survey of Space and Time (LSST) -- in which an algorithmic
treatment of lensing systems will be needed due to the sheer volume of data
these surveys will produce.Comment: 17 pages, 5 figures, 2 tables. Submitted to The Astrophysical
Journal. v3: updated authors, formatting, grammar, and reference
Identification of Galaxy-Galaxy Strong Lens Candidates in the DECam Local Volume Exploration Survey Using Machine Learning
We perform a search for galaxy-galaxy strong lens systems using a convolutional neural network (CNN) applied to imaging data from the first public data release of the DECam Local Volume Exploration Survey, which contains 1/4520 million astronomical sources covering 1/44000 deg2 of the southern sky to a 5σ point-source depth of g = 24.3, r = 23.9, i = 23.3, and z = 22.8 mag. Following the methodology of similar searches using Dark Energy Camera data, we apply color and magnitude cuts to select a catalog of 1/411 million extended astronomical sources. After scoring with our CNN, the highest-scoring 50,000 images were visually inspected and assigned a score on a scale from 0 (not a lens) to 3 (very probable lens). We present a list of 581 strong lens candidates, 562 of which are previously unreported. We categorize our candidates using their human-assigned scores, resulting in 55 Grade A candidates, 149 Grade B candidates, and 377 Grade C candidates. We additionally highlight eight potential quadruply lensed quasars from this sample. Due to the location of our search footprint in the northern Galactic cap (b > 10 deg) and southern celestial hemisphere (decl. < 0 deg), our candidate list has little overlap with other existing ground-based searches. Where our search footprint does overlap with other searches, we find a significant number of high-quality candidates that were previously unidentified, indicating a degree of orthogonality in our methodology. We report properties of our candidates including apparent magnitude and Einstein radius estimated from the image separation
- …
