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This paper presents a new model for the generation of axisymmetric concentrated vortices. The solution of a nonlinear equation for internal gravity waves in an unstable stratified atmosphere is obtained and analyzed within the framework of ideal hydrodynamics. The corresponding expressions describing the dependences on the radius for the radial and vertical velocity components in the inner and outer regions of the vortex include combinations of Bessel functions and modified Bessel functions. The proposed new nonlinear analytical model makes it possible to study the structure and nonlinear dynamics of vortices in the radial and vertical regions. The vortex is limited in height. The maximum vertical velocity component is reached at a certain height. Below this height, radial flows converge towards the axis, and above it, an outflow occurs. The resulting instability in the stratified atmosphere leads to an increase in the radial and vertical velocity components according to the hyperbolic sine law, which turns into exponential growth. The characteristic growth time is determined by the inverse growth rate of the instability. The formation of vortices with finite velocity components, which increase with time, is analyzed. The radial structure of the azimuthal velocity is determined by the structure of the initial perturbation and can change with height. The maximum rotation is reached at a certain height. The growth of the azimuth velocity occurs according to a super-exponential law., Comment: 17 pages, 4 figures. arXiv admin note: text overlap with arXiv:2408.14210

The problem of ponderomotive separation of ions with different charge-to-mass ratios under the influence of Alfven waves, which permanently exist in the magnetosphere in the form of geomagnetic pulsations, is posed. Formulas are derived for partial ponderomotive forces acting on light and heavy (metal) ions. In the quasi-hydrodynamic approximation, it was found that the Clarke number, which characterizes the metallicity of the plasma, is maximum at the minimum of the magnetic field on the field line along which the Alfv\'en wave propagates. Key words: ponderomotive forces, Alfv\'en waves, heavy ions, Clarke number., Comment: 10 pages

The Arkansas Department of Education partnered with the Regional Educational Laboratory Southwest to study the feasibility and effectiveness of using brief email and text message communications to increase the number of parent and guardian visits to the Reading Initiative for Student Excellence (R.I.S.E.) state literacy website. In November 2021 the department sent test messages to families to determine the percentage of households with children in kindergarten-grade 6 in Arkansas public schools that had a working email address or cell phone number and whether the percentage differed by school locale (rural or nonrural) or demographic composition (percentage of economically disadvantaged students, Black students and Hispanic students, or English learner students). Subsequently, the study team randomly assigned 700 Arkansas public elementary schools to one of eight conditions, which varied the mode of communication (email only or email and text message), the presentation of information (no graphic or with a graphic), and the type of sender (generic sender or known sender). In January 2022 households with children in these schools were sent three rounds of communications with information about literacy and a link to the R.I.S.E. website. The study examined the impact of these communications on whether parents and guardians clicked the link to visit the website (click rate) and conducted an exploratory analysis of differences in how long they spent on the website (time on page). The study found that nearly all households had a working email address or cell phone number. Households with children in rural schools or schools with higher percentages of economically disadvantaged students were less likely than other households to have a working email address. The percentage of households that had a working cell phone number did not vary by school locale or demographic composition. Nearly one in five households opened at least one email, and nearly 80 percent of households were delivered at least one text message. The click rate was highest for households assigned to receive both emails and text messages, with a graphic, and from a known sender. The higher click rate can be attributed to adding text messages and to sending communications from a known sender. The impact on the click rate was similar for schools in different locales and with different demographic compositions. The Arkansas Department of Education can use the findings from this study to inform decisions about how best to communicate with families about literacy and other evidence-based resources. The findings can also be used by other state and local education agencies to inform decisions about using email or text message communications to share resources with families. [For the Study Snapshot, see ED624335. For the appendixes, see ED624336.]

The College Completion Network conducted a systematic review of the research on advising strategies that support college completion. Several key findings can inform policy and practice: Holistic and comprehensive interventions that combine multiple components to meet student needs improve student outcomes. These types of interventions provide students with a comprehensive suite of advising, student services, academic support, and financial aid. Rigorous studies have consistently found long-term, positive effects on student outcomes. Proactive communication with sustained follow-up that spans a student's trajectory through college improves student outcomes. The review found that students benefit when colleges communicate proactively, pair outreach with consistent follow-up, and provide incentives for students to respond. Informational interventions, such as those delivered via text messaging or email campaigns, should provide targeted and actionable information with clear next steps. Student success can be bolstered when colleges provide a robust set of nonacademic supports through comprehensive case management. Now more than ever, college students require a range of nonacademic supports to ensure their success in college. Colleges can partner with case management organizations to connect students with mental health supports, childcare, transportation assistance, and access to food and other basic needs. As new evidence merges, practitioners can learn about the most effective approaches to providing nonacademic supports. [For "Advising for College Success: A Systematic Review of the Evidence. Appendix C," see ED626639. For "Advising for College Success: Policies, Practices, and Programs That Support Students on the Path to College Completion," see ED626635. For "Advising for College Success: Next Steps for Policymakers, Practitioners, and Researchers," see ED626636.]

The College Completion Network conducted a systematic review of the research literature on advising strategies, summarizing the evidence for a wide range of advising strategies that have been the focus of research conducted during the past 2 decades. Simultaneously, the network conducted virtual focus groups with administrators at 47 2-year and broad-access 4-year colleges with the goal of better understanding the advising policies, practices, and programs that colleges use to support student success. This report provides the full list of reviewed studies. [For "Advising for College Success: A Systematic Review of the Evidence," see ED626933. For "Advising for College Success: Policies, Practices, and Programs That Support Students on the Path to College Completion," see ED626635. For "Advising for College Success: Next Steps for Policymakers, Practitioners, and Researchers," see ED626636.]

From fall 2021 to summer 2022, the American Institutes for Research (AIR) conducted virtual focus groups with administrators at 47 colleges: a nationally representative sample of 36 2-year and broad-access 4-year colleges and a purposive sample of 11 colleges selected for their track record with advising. The study identified four key findings that can inform future research: (1) Advising policies, practices, and programs often focused on the first year of college, with the intent of setting students up for success at entry; (2) College administrators reported using different types of strategies for supporting students in the face of time and resource constraints; (3) College administrators reported using a combination of light-touch strategies (such as nudging) and more intensive strategies (such as proactive advising) to support students' progress through college; and (4) Increasingly, and especially since the onset of the COVID-19 pandemic, colleges have recognized the importance of meeting students' basic needs. College administrators can use the findings from this study to learn about approaches to advising other colleges are using, and the successes and challenges of implementation, and researchers who study advising and other student success initiatives can use the findings from this study to identify directions for future research. [For "Advising for College Success: Next Steps for Policymakers, Practitioners, and Researchers," see ED626636. For "Advising for College Success: A Systematic Review of the Evidence. Appendix C," see ED626639. For "Advising for College Success: A Systematic Review of the Evidence," see ED626933.]

From fall 2021 to summer 2022, the College Completion Network conducted virtual focus groups with administrators at 47 2-year and broad-access 4-year colleges with the goal of better understanding the advising policies, practices, and programs (hereafter referred to as "strategies") that colleges use to support student success. Simultaneously, the network conducted a systematic review of the research literature on advising strategies, summarizing the evidence for a wide range of advising strategies that have been the focus of research conducted during the past 2 decades. This brief considers the findings from each study side by side, distilling gaps between policy and practice and research. The brief answers the following three key questions: (1) Which advising strategies have strong evidence of success and are widely used?; (2) Which information and advising strategies are widely used, but have little or no evidence of success?; and (3) Which information and advising strategies have strong evidence of success, but are not widely used? Policymakers and practitioners may use the findings from this gaps analysis to make decisions about which advising strategies to implement, adapt, or discontinue. Likewise, researchers can use the findings to prioritize areas for future research. [For "Advising for College Success: A Systematic Review of the Evidence," see ED626933. For "Advising for College Success: Policies, Practices, and Programs That Support Students on the Path to College Completion," see ED626635. For "Advising for College Success: A Systematic Review of the Evidence. Appendix C," see ED626639.]

Over the past 20 years, an estimated 30 to 35 million Americans have left college with some academic credit but no postsecondary credential. Such students are more likely to be students of color, have dependents, face unmet financial needs, or experience other hardships that cause them to struggle in degree programs. A study team drawn from across the College Completion Network conducted a policy and practice scan to better understand how colleges support returning students. The team conducted focus groups with administrators at 59 2-year and broad-access 4-year colleges across the United States. The focus groups centered on strategies colleges use to identify, recruit, and support students who left college without a degree. Based on the information learned, this brief shares five lessons for practitioners interested in supporting returning college students.

Regional Educational Laboratory Southwest partnered with the Arkansas Department of Education to examine Arkansas's middle school and high school indicators of postsecondary readiness and success, building on an earlier study of these indicators (Hester et al., 2021). Academic indicators include attaining proficiency on state academic examinations, grade point average, enrollment in advanced courses, and community service learning. Behavioral indicators include attendance, suspension, and expulsion. Using data on statewide grade 6 cohorts from 2008/09 and 2009/10, the study examined the percentages of students who attained the readiness and success indicators and the percentages of students who attained postsecondary readiness and success outcomes by gender, race/ethnicity, eligibility for the National School Lunch Program, English learner student status, disability status, age, and district locale. The study also examined whether the predictive accuracy, specificity, and strength of the indicators varied by these student groups. This document presents the following three appendixes that accompany the study: (1) Data and Methods; (2) Supporting analyses; and (3) Supplemental analyses. [For the full report, see ED624014.]

Regional Educational Laboratory Southwest partnered with the Arkansas Department of Education (ADE) to examine Arkansas's middle and high school indicators of postsecondary readiness and success, building on an earlier study of these indicators (Hester et al., 2021). Academic indicators include attaining proficiency on state achievement tests, grade point average, enrollment in advanced courses, and community service learning. Behavioral indicators include attendance, suspension, and expulsion. Using data on statewide grade 6 cohorts from 2008/09 and 2009/10, the study examined the percentages of students who attained the readiness and success indicators and the percentages of students who attained postsecondary readiness and success outcomes by gender, race/ethnicity, eligibility for the National School Lunch Program, English learner student status, disability status, age, and district locale. The study also examined whether the predictive accuracy, specificity, and strength of the indicators varied by these student groups. Three key findings emerged. First, the attainment of indicators of postsecondary readiness and success differed substantially for nearly all student groups, with the number of substantial differences on academic indicators exceeding those on behavioral indicators. The largest number of substantial differences in the attainment of academic indicators were between Black and White students, between students eligible and ineligible for the National School Lunch Program (an indicator of economic disadvantage), and between students who entered grade 6 before and after age 13. Second, attainment of postsecondary readiness and success outcomes varied substantially across student groups, with the largest differences between students with and without a disability. Third, predictive accuracy (the percentage of students with the same predicted and actual outcomes) and strength (the relative importance of a single indicator) were similar across student groups in most cases. Leaders at ADE and in Arkansas districts can use these findings to identify appropriate indicators of postsecondary readiness and success and to target supports toward student groups who most need them. These findings can help leaders identify and address disparities such as inequitable access to resources and supportive learning environments. [For the appendixes, see ED624015.]

The Texas Education Agency offers grants for districts to implement school turnaround strategies at low-performing schools. Districts that receive these grants can implement a school turnaround strategy (referred to as a district-managed restart strategy) that includes replacing most of the principals and teachers at schools that the district identifies as struggling and needing additional support. From 2015/16 to 2018/19, 29 schools across four urban and suburban districts in Texas implemented a district-managed restart strategy in three cohorts: one district began in 2015/16, another in 2017/18, and two in 2018/19. This study used longitudinal administrative data and interviews with district and school leaders to examine implementation of the restart strategy and its effects on teacher and principal mobility, student achievement, and student attendance. Nearly 80 percent of the teachers at schools in the year before implementation of the restart strategy left before the beginning of the restart school year. Educators who arrived at restart schools were more likely to have more than three years of experience and to have an advanced degree than those who left or stayed. The restart strategy had a positive effect on student achievement in reading and math and on student attendance, but the effect on attendance was not sustained beyond the first year of implementation. Nearly all restart schools met accountability standards within the first three years of implementation. Finally, interviews with district and school leaders suggested that recruiting high-performing teachers to relocate to restart schools was time consuming and that the grant-funded salary stipend might not have been a large enough incentive for high-performing teachers to relocate. State leaders can use the results of this study to make decisions about continuing to offer grants for districts to implement the district-managed restart strategy in their low performing schools. [For the Study Snapshot, see ED621561. For the Appendixes, see ED621560.]

MATSim (Multi-Agent Transport Simulation Toolkit) is an open source large-scale agent-based transportation planning project applied to various areas like road transport, public transport, freight transport, regional evacuation, etc. BEAM (Behavior, Energy, Autonomy, and Mobility) framework extends MATSim to enable powerful and scalable analysis of urban transportation systems. The agents from the BEAM simulation exhibit 'mode choice' behavior based on multinomial logit model. In our study, we consider eight mode choices viz. bike, car, walk, ride hail, driving to transit, walking to transit, ride hail to transit, and ride hail pooling. The 'alternative specific constants' for each mode choice are critical hyperparameters in a configuration file related to a particular scenario under experimentation. We use the 'Urbansim-10k' BEAM scenario (with 10,000 population size) for all our experiments. Since these hyperparameters affect the simulation in complex ways, manual calibration methods are time consuming. We present a parallel Bayesian optimization method with early stopping rule to achieve fast convergence for the given multi-in-multi-out problem to its optimal configurations. Our model is based on an open source HpBandSter package. This approach combines hierarchy of several 1D Kernel Density Estimators (KDE) with a cheap evaluator (Hyperband, a single multidimensional KDE). Our model has also incorporated extrapolation based early stopping rule. With our model, we could achieve a 25% L1 norm for a large-scale BEAM simulation in fully autonomous manner. To the best of our knowledge, our work is the first of its kind applied to large-scale multi-agent transportation simulations. This work can be useful for surrogate modeling of scenarios with very large populations., Comment: LOD'2022 (Nature Springer Computer Science Proceedings - LNCS)

This report presents an approach to evaluating networked improvement communities (NICs) and describes the tools used to apply the approach to a formative evaluation of the Minnesota Alternative Learning Center Networked Improvement Community (Minnesota ALC NIC). In fall 2019 leaders at the Minnesota Department of Education requested support from the Regional Educational Laboratory (REL) Midwest to address low high school graduation rates among students in alternative learning centers (ALCs). In partnership with five ALCs, the department and the REL Midwest participated in the Minnesota ALC NIC to raise graduation rates at ALCs by improving their use of competency-based credit recovery practices. REL Midwest researchers then developed an approach for evaluating networked improvement communities (NICs) and applied it to the Minnesota ALC NIC. This report shares the findings from the evaluation, using them to illustrate the process of analyzing and interpreting the data collected on NIC implementation, and discusses the limitations of the tools. The approach can be adapted to evaluate other NICs in prekindergarten-grade 12 education. The tools require basic quantitative and qualitative analysis skills, and evaluators or facilitators can adapt them to provide formative feedback on whether an NIC is operating as intended.

In Minnesota, as in many other states, not all students have access to the types of educational experiences in high school that are likely to lead to high-paying jobs. If Minnesota policymakers and practitioners are to be well positioned to reduce achievement gaps that lead to different career and college outcomes, they must have reliable data on the postsecondary pathways Minnesota public high school graduates take, as well as information about differences in pathways and outcomes for different groups of students. Members of the Midwest Career Readiness Research Alliance collaborated with Regional Educational Laboratory Midwest to conduct a study that describes the postsecondary pathways of Minnesota public high school graduates, including the pathways graduates take within one year of high school graduation and their degree attainment and employment outcomes six years later. The study also examined differences in initial pathways, degree attainment, and employment outcomes for students with different characteristics. Using data from the Minnesota Statewide Longitudinal Education Data System, the study examined the initial postsecondary pathways of Minnesota public high school students who graduated from high school between 2008 and 2015. The study also examined the college certificate and degree attainment and employment outcomes of Minnesota public high school students who graduated from high school between 2008 and 2010. The study describes differences in initial postsecondary pathways, college certificate and degree attainment, and employment for students from different groups. The study found that within one year of high school graduation, nearly all Minnesota public high school graduates were enrolled in college or employed. There were differences in initial postsecondary pathway by student characteristics but not by rurality. Graduates who had disabilities, graduates who had limited English proficiency, Hispanic graduates, and American Indian/Alaska Native graduates were the most likely to be neither employed nor enrolled in college within one year of high school graduation. Six years after high school graduation, 48 percent of graduates had not earned a college certificate or degree. Thirty-seven percent of graduates had earned a bachelor's degree or higher, 11 percent of graduates had earned an associate's degree, and 4 percent of graduates had earned a college certificate. In addition, six years after high school graduation, 71 percent of graduates were employed, and their median annual earnings were $22,717. Finally, there were differences in college certificate and degree attainment, employment, and earnings by student characteristics. These differences remained when comparing graduates who participated in the same initial postsecondary pathway. The results of this study suggest that high schools might consider expanding access to college readiness opportunities for students from diverse backgrounds; targeting resources to students who are the most at risk during the transition to postsecondary education and employment; and sharing information with students about the earnings of past cohorts of students and how they differed across postsecondary pathways. The results of this study also suggest that colleges might consider opportunities to better support these students after they enroll in college.

During the past decade, states and districts have made significant investments in developing systems to measure teacher performance. The goals of such systems are to improve practice, inform professional growth, and ultimately improve student learning. In the very best of these systems, educators know the expected teaching standards and receive timely, relevant, and actionable data about their professional practices; districts align supports and resources for improvement; and educators and district staff monitor data about how instructional practices are influencing student learning. Unfortunately, not all systems work this well. Implementation often has focused on compliance and accountability rather than growth in teachers' professional practice. The Beyond Accountability project aimed to improve the way that districts gather and use evaluation system data, enabling them to better develop and support teachers, and provide them with more differentiated and high-quality opportunities to improve their instructional practice. To achieve this goal, the project employed a continuous improvement approach, specifically plan-do-study-act (PDSA) cycles. Each district identified a specific challenge to be addressed and conducted a root-cause analysis to understand the sources of the challenge. Through an iterative process, each district developed, tested, and revised a strategy to address the challenge. With support from AIR, each district collected and analyzed outcome data to inform revisions to the strategy. The project's goals for each district were to improve instructional quality, increase teacher satisfaction with opportunities or mechanisms to improve teacher practice, and increase district capacity to engage in improvement efforts. This report provides information about the project and the lessons learned by both AIR and the participating districts. It provides specific examples of participating districts' work, including goals and participants, that may be useful to other districts facing similar challenges or interested in using similar approaches. AIR has produced a separate, comprehensive evaluation report that describes the extent to which the overall project goals were achieved; the high-level findings are briefly highlighted in Appendix A. Appendix B provides the tools and materials used during the project (e.g., meeting agendas and planning templates) that other districts might use or adapt for their own work.

This brief presents a review of research and current state practices as they relate to measures that Iowa might consider for its federal accountability indicator of school quality or student success--specifically, for inclusion within a composite index of postsecondary readiness. Section 1 of this brief introduces a framework for evaluating and selecting measures of postsecondary readiness for accountability, reviews the four components of Iowa's DCCR, and summarizes the research on the relationship between measures of postsecondary readiness and student postsecondary outcomes embedded in the four components of Iowa's DCCR. Section 2 summarizes current practices on the use of measures of postsecondary readiness in other states.

This article introduces BISTRO, a new open source transportation planning decision support system that uses an agent-based simulation and optimization approach to anticipate and develop adaptive plans for possible technological disruptions and growth scenarios. The new framework was evaluated in the context of a machine learning competition hosted within Uber Technologies, Inc., in which over 400 engineers and data scientists participated. For the purposes of this competition, a benchmark model, based on the city of Sioux Falls, South Dakota, was adapted to the BISTRO framework. An important finding of this study was that in spite of rigorous analysis and testing done prior to the competition, the two top-scoring teams discovered an unbounded region of the search space, rendering the solutions largely uninterpretable for the purposes of decision-support. On the other hand, a follow-on study aimed to fix the objective function, served to demonstrate BISTRO's utility as a human-in-the-loop cyberphysical system: one that uses scenario-based optimization algorithms as a feedback mechanism to assist urban planners with iteratively refining objective function and constraints specification on intervention strategies such that the portfolio of transportation intervention strategy alternatives eventually chosen achieves high-level regional planning goals developed through participatory stakeholder engagement practices.

The final goal of the intelligence augmentation process is a complete merger of biological brains and computers allowing for integration and mutual enhancement between computer's speed and memory and human's intelligence. This process, known as uploading, analyzes human brain in detail sufficient to understand its working patterns and makes it possible to simulate said brain on a computer. As it is likely that such simulations would quickly evolve or be modified to achieve superintelligence it is very important to make sure that the first brain chosen for such a procedure is a suitable one. In this paper, we attempt to answer the question: Whom to upload first?

Polar codes are the latest breakthrough in coding theory, as they are the first family of codes with explicit construction that provably achieve the symmetric capacity of discrete memoryless channels. Ar{\i}kan's polar encoder and successive cancellation decoder have complexities of $N \log N$, for code length $N$. Although, the complexity bound of $N \log N$ is asymptotically favorable, we report in this work methods to further reduce the encoding and decoding complexities of polar coding. The crux is to relax the polarization of certain bit-channels without performance degradation. We consider schemes for relaxing the polarization of both \emph{very good} and \emph{very bad} bit-channels, in the process of channel polarization. Relaxed polar codes are proved to preserve the capacity achieving property of polar codes. Analytical bounds on the asymptotic and finite-length complexity reduction attainable by relaxed polarization are derived. For binary erasure channels, we show that the computation complexity can be reduced by a factor of 6, while preserving the rate and error performance. We also show that relaxed polar codes can be decoded with significantly reduced latency. For AWGN channels with medium code lengths, we show that relaxed polar codes can have lower error probabilities than conventional polar codes, while having reduced encoding and decoding computation complexities., Comment: Conference version,Relaxed Channel Polarization for Reduced Complexity Polar Coding, accepted for presentation at IEEE Wireless Communications and Networking Conference WCNC 2015

We derive the expression for the ponderomotive force in the real multicomponent magnetospheric plasma containing heavy ions. The ponderomotive force considered includes the induced magnetic moment of all the species and arises due to inhomogeneity of the traveling low-frequency electromagnetic wave amplitude in the nonuniform medium. The nonlinear stationary force balance equation is obtained taking into account the gravitational and centrifugal forces for the plasma consisting of the electrons, protons and heavy ions (He$^{+}$). The background geomagnetic field is taken for the dayside of the magnetosphere, where the magnetic field have magnetic "holes" (Antonova and Shabansky 1968). The balance equation is solved numerically to obtain the nonlinear density distribution of ions (H$^{+}$) in the presence of heavy ions (He$^{+}$). It is shown that for frequencies less than the helium gyrofrequency at the equator the nonlinear plasma density perturbations are peaked in the vicinity of the equator due to the action of the ponderomotive force. A comparison of the cases of the dipole and dayside magnetosphere is provided. It is obtained that the presence of heavy ions leads to decrease of the proton density modification., Comment: Accepted for publication in Astrophysics and Space Science

We investigate analytically and numerically a nonlinear modification of the magnetospheric plasma density under the action of the ponderomotive force induced by ULF traveling waves, using the nonlinear stationary force balance equation. This equation is applied to both the dipole and dayside magnetosphere having one and two minima of the geomagnetic field near the magnetospheric boundary. The separate and joint actions of the ponderomotive, centrifugal, and gravitational forces on the density distribution are shown., Comment: Accepted for publication in Astrophysics & Space Science