117 research outputs found
Reading-to-Writing Mediation Model of Higher-Order Literacy
INTRODUCTION: Writing difficulties frequently manifest comorbidly with reading challenges, and reading is implicated in particular acts of writing, such as reviewing and editing. Despite what is known, however, there remain significant barriers to understanding the nature of reading-writing relations, as few studies are comprehensive in the number and types of literacy skills evaluated. This study consists of a secondary data analysis of two studies employing structural equation modeling (SEM) to evaluate relations among reading and writing components skills independently, using the Direct and Inferential Mediation Model (DIME) of reading comprehension and Not-so-Simple View of Writing (NSVW) as theoretical frameworks.
METHODS: We examine relations between reading and writing components from these models with a sample of upper elementary students with/at-risk for learning disabilities (
RESULTS: The findings suggest that higher order fluency and comprehension skills are differentially related to writing activities and products.
DISCUSSION: The pattern of results helps elucidate the mechanisms of how various reading and writing skills transfer and relate. The results have implications for targeted and implicit instruction in multicomponent interventions and the use of screeners to identify areas of risk
End-to-End Modeling of the TDM Readout System for CMB-S4
The CMB-S4 experiment is developing next-generation ground-based microwave
telescopes to observe the Cosmic Microwave Background with unprecedented
sensitivity. This will require an order of magnitude increase in the 100 mK
detector count, which in turn increases the demands on the readout system. The
CMB-S4 readout will use time division multiplexing (TDM), taking advantage of
faster switches and amplifiers in order to achieve an increased multiplexing
factor. To facilitate the design of the new readout system, we have developed a
model that predicts the bandwidth and noise performance of this circuity and
its interconnections. This is then used to set requirements on individual
components in order to meet the performance necessary for the full system. We
present an overview of this model and compare the model results to the
performance of both legacy and prototype readout hardware.Comment: This manuscript was submitted to the Journal of Low Temperature
Physics as part of the special issue "LTD20", supporting the conference
contribution RP-00
The International Comprehensive Ocean-Atmosphere Data Set – meeting users needs and future priorities
The International Comprehensive Ocean-Atmosphere Data Set (ICOADS) is a collection and archive of in situ marine observations, which has been developed over several decades as an international project and recently guided by formal international partnerships and the ICOADS Steering Committee. ICOADS contains observations from many different observing systems encompassing the evolution of measurement technology since the 18th century. ICOADS provides an integrated source of observations for a range of applications including research and climate monitoring, and forms the main marine in situ surface data source, e.g., near-surface ocean observations and lower atmospheric marine-meteorological observations from buoys, ships, coastal stations, and oceanographic sensors, for oceanic and atmospheric research and reanalysis. ICOADS has developed ways to incorporate user and reanalyses feedback information associated with permanent unique identifiers and is also the main repository for data that have been rescued from ships’ logbooks and other marine data digitization activities. ICOADS has been adopted widely because it provides convenient access to a range of observation types, globally, and through the entire marine instrumental record. ICOADS has provided a secure home for such observations for decades. Because of the increased volume of observations, particularly those available in near-real-time, and an expansion of their diversity, the ICOADS processing system now requires extensive modernization. Based on user feedback, we will outline the improvements that are required, the challenges to their implementation, and the benefits of upgrading this important and diverse marine archive and distribution activity
Observing requirements for long-term climate records at the ocean surface
Observations of conditions at the ocean surface have been made for centuries, contributing to some of the longest instrumental records of climate change. Most prominent is the climate data record (CDR) of sea surface temperature (SST), which is itself essential to the majority of activities in climate science and climate service provision. A much wider range of surface marine observations is available however, providing a rich source of data on past climate. We present a general error model describing the characteristics of observations used for the construction of climate records, illustrating the importance of multi-variate records with rich metadata for reducing uncertainty in CDRs. We describe the data and metadata requirements for the construction of stable, multi-century marine CDRs for variables important for describing the changing climate: SST, mean sea level pressure, air temperature, humidity, winds, clouds, and waves. Available sources of surface marine data are reviewed in the context of the error model. We outline the need for a range of complementary observations, including very high quality observations at a limited number of locations and also observations that sample more broadly but with greater uncertainty. We describe how high-resolution modern records, particularly those of high-quality, can help to improve the quality of observations throughout the historical record. We recommend the extension of internationally-coordinated data management and curation to observation types that do not have a primary focus of the construction of climate records. Also recommended is reprocessing the existing surface marine climate archive to improve and quantify data and metadata quality and homogeneity. We also recommend the expansion of observations from research vessels and high quality moorings, routine observations from ships and from data and metadata rescue. Other priorities include: field evaluation of sensors; resources for the process of establishing user requirements and determining whether requirements are being met; and research to estimate uncertainty, quantify biases and to improve methods of construction of CDRs. The requirements developed in this paper encompass specific actions involving a variety of stakeholders, including funding agencies, scientists, data managers, observing network operators, satellite agencies, and international co-ordination bodies
Ship-based contributions to global ocean, weather, and climate observing systems
The role ships play in atmospheric, oceanic, and biogeochemical observations is described with a focus on measurements made within 100 m of the ocean surface. Ships include merchant and research vessels, cruise liners and ferries, fishing vessels, coast guard, military, and other government-operated ships, yachts, and a growing fleet of automated surface vessels. The present capabilities of ships to measure essential climate/ocean variables and the requirements from a broad community to address operational, commercial, and scientific needs are described. Following the guidance from the OceanObs'19 organizing committee, the authors provide a vision to expand observations needed from ships to understand and forecast the exchanges across the ocean-atmosphere interface. The vision addresses (1) recruiting vessels to improve both spatial and temporal sampling, (2) conducting multi-variate sampling on ships, (3) raising technology readiness levels of automated shipboard sensors and ship-to-shore data communications, (4) advancing quality evaluation of observations, and (5) developing a unified data management approach for observations and metadata that meets the needs of a diverse user community. Recommendations are made focusing on integrating private and autonomous vessels into the observing system, investing in sensor and communications technology development, developing an integrated data management structure that includes all types of ships, and moving towards a quality evaluation process that will result in a subset of ships being defined as mobile reference ships that will support climate studies. We envision a future where commercial, research, and privately-owned vessels are making multivariate observations using a combination of automated and human-observed measurements. All data and metadata will be documented, tracked, evaluated, distributed, and archived to benefit users of marine data. This vision looks at ships as a holistic network, not a set of disparate commercial, research, and/or third-party activities working in isolation, to bring these communities together for the mutual benefit of all
The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters
We present the temperature and polarization angular power spectra measured by
the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time
data collected during 2013-14 using two detector arrays at 149 GHz, from 548
deg of sky on the celestial equator. We use these spectra, and the spectra
measured with the MBAC camera on ACT from 2008-10, in combination with Planck
and WMAP data to estimate cosmological parameters from the temperature,
polarization, and temperature-polarization cross-correlations. We find the new
ACTPol data to be consistent with the LCDM model. The ACTPol
temperature-polarization cross-spectrum now provides stronger constraints on
multiple parameters than the ACTPol temperature spectrum, including the baryon
density, the acoustic peak angular scale, and the derived Hubble constant.
Adding the new data to planck temperature data tightens the limits on damping
tail parameters, for example reducing the joint uncertainty on the number of
neutrino species and the primordial helium fraction by 20%.Comment: 23 pages, 25 figure
Microwave multiplexing on the Keck Array
We describe an on-sky demonstration of a microwave-multiplexing readout
system in one of the receivers of the Keck Array, a polarimetry experiment
observing the cosmic microwave background at the South Pole. During the austral
summer of 2018-2019, we replaced the time-division multiplexing readout system
with microwave-multiplexing components including superconducting microwave
resonators coupled to radio-frequency superconducting quantum interference
devices at the sub-Kelvin focal plane, coaxial-cable plumbing and amplification
between room temperature and the cold stages, and a SLAC Microresonator Radio
Frequency system for the warm electronics. In the range 5-6 GHz, a single
coaxial cable reads out 528 channels. The readout system is coupled to
transition-edge sensors, which are in turn coupled to 150-GHz slot-dipole
phased-array antennas. Observations began in April 2019, and we report here on
an initial characterization of the system performance.Comment: 9 pages, 11 figures, Accepted by the Journal of Low Temperature
Physics (Proceedings of the 18th International Workshop on Low Temperature
Detectors
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