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Sample records for advanced tow placement

  1. Customized ATP towpreg. [Automated Tow Placement

    NASA Technical Reports Server (NTRS)

    Sandusky, Donald A.; Marchello, Joseph M.; Baucom, Robert M.; Johnston, Norman J.

    1992-01-01

    Automated tow placement (ATP) utilizes robotic technology to lay down adjacent polymer-matrix-impregnated carbon fiber tows on a tool surface. Consolidation and cure during ATP requires that void elimination and polymer matrix adhesion be accomplished in the short period of heating and pressure rolling that follows towpreg ribbon placement from the robot head to the tool. This study examined the key towpreg ribbon properties and dimensions which play a significant role in ATP. Analysis of the heat transfer process window indicates that adequate heating can be achieved at lay down rates as high as 1 m/sec. While heat transfer did not appear to be the limiting factor, resin flow and fiber movement into tow lap gaps could be. Accordingly, consideration was given to towpreg ribbon having uniform yet non-rectangular cross sections. Dimensional integrity of the towpreg ribbon combined with customized ribbon architecture offer great promise for processing advances in ATP of high performance composites.

  2. Structural Assessment of Advanced Composite Tow-Steered Shells

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Stanford, Bret K.; Hrinda, Glenn A.; Wang, Zhuosong; Martin, Robert a.; Kim, H. Alicia

    2013-01-01

    The structural performance of two advanced composite tow-steered shells, manufactured using a fiber placement system, is assessed using both experimental and analytical methods. The fiber orientation angles vary continuously around the shell circumference from 10 degrees on the shell crown and keel, to 45 degrees on the shell sides. The two shells differ in that one shell has the full 24-tow course applied during each pass of the fiber placement system, while the second shell uses the fiber placement system s tow drop/add capability to achieve a more uniform shell wall thickness. The shells are tested in axial compression, and estimates of their prebuckling axial stiffnesses and bifurcation buckling loads are predicted using linear finite element analyses. These preliminary predictions compare well with the test results, with an average agreement of approximately 10 percent.

  3. Design and Analysis of Tow-Steered Composite Shells Using Fiber Placement

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey

    2008-01-01

    In this study, a sub-scale advanced composite shell design is evaluated to determine its potential for use on a future aircraft fuselage. Two composite shells with the same nominal 8-ply [+/-45/+/-Theta](sub s) layup are evaluated, where Theta indicates a tow-steered ply. To build this shell, a fiber placement machine would be used to steer unidirectional prepreg tows as they are placed around the circumference of a 17-inch diameter right circular cylinder. The fiber orientation angle varies continuously from 10 degrees (with respect to the shell axis of revolution) at the crown, to 45 degrees on the side, and back to 10 degrees on the keel. All 24 tows are placed at each point on every fiber path in one structure designated as the shell with overlaps. The resulting pattern of tow overlaps causes the laminate thickness to vary between 8 and 16 plies. The second shell without tow overlaps uses the capability of the fiber placement machine to cut and add tows at any point along the fiber paths to fabricate a shell with a nearly uniform 8-ply laminate thickness. Issues encountered during the design and analysis of these shells are presented and discussed. Static stiffness and buckling loads of shells with tow-steered layups are compared with the performance of a baseline quasi-isotropic shell using both finite element analyses and classical strength of materials theory.

  4. Design and Manufacturing of Tow-Steered Composite Shells Using Fiber Placement

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Tatting, Brian F.; Smith, Brett H.; Stevens, Randy S.; Occhipiniti, Gina P.; Swift, Jonathan B.; Achary, David C.; Thornburgh, Robert P.

    2009-01-01

    Advanced composite shells that may offer the potential to improve the structural performance of future aircraft fuselage structures were developed under this joint NASA-industry collaborative effort. Two cylindrical shells with tailored, tow-steered layups and continuously varying fiber angle orientations were designed and built at the National Center for Advanced Manufacturing - Louisiana Partnership. The shells were fabricated from unidirectional IM7/8552 graphite-epoxy pre-preg slit tape material fiber-placed on a constant-diameter mandrel. Each shell had the same nominal 8-ply [plus or minus 45/plus or minus Theta]s layup, where the nominal fiber angle in the tow-steered plies varied continuously from 10 degrees along the crown to 45 degrees on each side, then back to 10 degrees on the keel. One shell was fabricated with all 24 tows placed during each pass of the fiber placement machine, resulting in many tow overlaps on the shell surface. The fiber placement machine's individual tow cut/restart capability was also used to manufacture a second shell with tow drops and a more uniform laminate thickness. This paper presents an overview of the detailed design and manufacturing processes for these shells, and discusses issues encountered during their fabrication and post-cure evaluation. Future plans for structural testing and analyses of the shells are also discussed.

  5. Mechanical characterization of two thermoplastic composites fabricated by automated tow placement

    NASA Technical Reports Server (NTRS)

    Dickinson, Larry C.; Deaton, Jerry W.

    1993-01-01

    AS4/PEEK towpreg and IM7/Radel 8320 slit tape were used to make flat panels by automated tow placement. The panels were tested in notched and un-notched tension, notched and un-notched compression and compression after impact (CAI) at room temperature and under hot/wet conditions (notched and un-notched compression and CAI only). The properties were compared with AS4/PEEK tape laminate properties found in the literature. The tow placed AS4/PEEK material was stronger in tension but weaker in compression than the AS4/PEEK tape laminates. The tow placed AS4/PEEK was stronger but less stiff than the tow placed IM7/Radel 8320 in all compression tests. The IM7/Radel performed better in all other mechanical tests. The IM7/Radel outperformed the AS4/PEEK in all CAI tests.

  6. Structural Performance of Advanced Composite Tow-Steered Shells With Cutouts

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Turpin, Jason D.; Stanford, Bret K.; Martin, Robert A.

    2014-01-01

    The structural performance of two advanced composite tow-steered shells with cutouts, manufactured using an automated fiber placement system, is assessed using both experimental and analytical methods. The shells' fiber orientation angles vary continuously around their circumference from +/-10 degrees on the crown and keel, to +/-45 degrees on the sides. The raised surface features on one shell result from application of all 24 tows during each fiber placement system pass, while the second shell uses the system's tow drop/add capability to achieve a more uniform wall thickness. These unstiffened shells were previously tested in axial compression and buckled elastically. A single cutout, scaled to represent a passenger door on a commercial aircraft, is then machined into one side of each shell. The prebuckling axial stiffnesses and bifurcation buckling loads of the shells with cutouts are also computed using linear finite element structural analyses for initial comparisons with test data. When retested, large deflections were observed around the cutouts, but the shells carried an average of 92 percent of the axial stiffness, and 86 percent of the buckling loads, of the shells without cutouts. These relatively small reductions in performance demonstrate the potential for using tow steering to mitigate the adverse effects of typical design features on the overall structural performance.

  7. Structural Characterization of Advanced Composite Tow-Steered Shells with Large Cutouts

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Turpin, Jason D.; Gardner, Nathaniel W.; Stanford, Bret K.; Martin, Robert A.

    2015-01-01

    The structural performance of two advanced composite tow-steered shells with large cutouts, manufactured using an automated fiber placement system, is assessed using both experimental and analytical methods. The fiber orientation angles of the shells vary continuously around their circumference from +/- 10 degrees on the crown and keel, to +/- 45 degrees on the sides. The raised surface features on one shell result from application of all 24 tows during each fiber placement system pass, while the second shell uses the tow drop/add capability of the system to achieve a more uniform wall thickness. These unstiffened shells, both without and with small cutouts, were previously tested in axial compression and buckled elastically. In this study, a single unreinforced cutout, scaled to represent a cargo door on a commercial aircraft, is machined into one side of each shell. The prebuckling axial stiffnesses and bifurcation buckling loads of these shells with large cutouts are also computed using linear finite element structural analyses for preliminary comparisons with test data. During testing, large displacements are observed around the large cutouts, but the shells maintain an average of 91 percent of the axial stiffness, and also carry 85 percent of the buckling loads, when compared to the pristine shells without cutouts. These relatively small reductions indicate that there is great potential for using tow steering to mitigate the adverse effects of large cutouts on the overall structural performance.

  8. Imperfection Insensitivity Analyses of Advanced Composite Tow-Steered Shells

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Farrokh, Babak; Stanford, Bret K.; Weaver, Paul M.

    2016-01-01

    Two advanced composite tow-steered shells, one with tow overlaps and another without overlaps, were previously designed, fabricated and tested in end compression, both without cutouts, and with small and large cutouts. In each case, good agreement was observed between experimental buckling loads and supporting linear bifurcation buckling analyses. However, previous buckling tests and analyses have shown historically poor correlation, perhaps due to the presence of geometric imperfections that serve as failure initiators. For the tow-steered shells, their circumferential variation in axial stiffness may have suppressed this sensitivity to imperfections, leading to the agreement noted between tests and analyses. To investigate this further, a numerical investigation was performed in this study using geometric imperfections measured from both shells. Finite element models of both shells were analyzed first without, and then, with measured imperfections that were then, superposed in different orientations around the shell longitudinal axis. Small variations in both the axial prebuckling stiffness and global buckling load were observed for the range of imperfections studied here, which suggests that the tow steering, and resulting circumferentially varying axial stiffness, may result in the test-analysis correlation observed for these shells.

  9. Advanced Placement Courses and American Indian Performance

    ERIC Educational Resources Information Center

    Moore, George; Slate, John R.

    2010-01-01

    Enrollment in Advanced Placement (AP) courses and performance on Advanced Placement examinations for American Indians in the U.S. for 2007 was analyzed. Scores on AP examinations, overall and then for five AP courses, were compared to the AP examination scores of White students. In every case, American Indians had AP examination scores that were…

  10. Advanced in In Situ Inspection of Automated Fiber Placement Systems

    NASA Technical Reports Server (NTRS)

    Juarez, Peter D.; Cramer, K. Elliott; Seebo, Jeffrey P.

    2016-01-01

    Automated Fiber Placement (AFP) systems have been developed to help take advantage of the tailorability of composite structures in aerospace applications. AFP systems allow the repeatable placement of uncured, spool fed, preimpregnated carbon fiber tape (tows) onto substrates in desired thicknesses and orientations. This automated process can incur defects, such as overlapping tow lines, which can severely undermine the structural integrity of the part. Current defect detection and abatement methods are very labor intensive, and still mostly rely on human manual inspection. Proposed is a thermographic in situ inspection technique which monitors tow placement with an on board thermal camera using the preheated substrate as a through transmission heat source. An investigation of the concept is conducted, and preliminary laboratory results are presented. Also included will be a brief overview of other emerging technologies that tackle the same issue. Keywords: Automated Fiber Placement, Manufacturing defects, Thermography

  11. Advances in in situ inspection of automated fiber placement systems

    NASA Astrophysics Data System (ADS)

    Juarez, Peter D.; Cramer, K. Elliott; Seebo, Jeffrey P.

    2016-05-01

    Automated Fiber Placement (AFP) systems have been developed to help take advantage of the tailorability of composite structures in aerospace applications. AFP systems allow the repeatable placement of uncured, spool fed, preimpregnated carbon fiber tape (tows) onto substrates in desired thicknesses and orientations. This automated process can incur defects, such as overlapping tow lines, which can severely undermine the structural integrity of the part. Current defect detection and abatement methods are very labor intensive, and still mostly rely on human manual inspection. Proposed is a thermographic in situ inspection technique which monitors tow placement with an on board thermal camera using the preheated substrate as a through transmission heat source. An investigation of the concept is conducted, and preliminary laboratory results are presented. Also included will be a brief overview of other emerging technologies that tackle the same issue.

  12. Modern Agriculture in Advanced Placement Human Geography.

    ERIC Educational Resources Information Center

    Lanegran, David A.

    2000-01-01

    Discusses the four sections of the Advanced Placement (AP) human geography course focusing on agriculture: (1) development and diffusion of agriculture; (2) major agricultural production regions; (3) rural land use and change; and (4) impacts of modern agricultural change. Includes references and a resource list. (CMK)

  13. Advanced Placement Economics. Macroeconomics: Student Activities.

    ERIC Educational Resources Information Center

    Morton, John S.

    This book is designed to help advanced placement students better understand macroeconomic concepts through various activities. The book contains 6 units with 64 activities, sample multiple-choice questions, sample short essay questions, and sample long essay questions. The units are entitled: (1) "Basic Economic Concepts"; (2) "Measuring Economic…

  14. Advanced Placement Economics. Teacher Resource Manual.

    ERIC Educational Resources Information Center

    Morton, John S.

    This book, in conjunction with the student activities books for macroeconomics and microeconomics, is designed for teaching the Advanced Placement Economics course. The book contains five units for the microeconomic portion and six units for the macroeconomic portion of the text. Along with the many activities are sample multiple-choice questions,…

  15. BIBLIOGRAPHIC GUIDE FOR ADVANCED PLACEMENT, LATIN.

    ERIC Educational Resources Information Center

    BARRON, ROBERT; ROSELLE, LEONE

    LITERARY AND CRITICAL WORKS, REFERENCE BOOKS, PERIODICALS, RECORDS, FILMS, AND FILMSTRIPS DEALING WITH ROMAN LITERATURE, HISTORY, CIVILIZATION, MYTHOLOGY, AND LANGUAGE ARE INCLUDED IN THIS BIBLIOGRAPHY OF RECOMMENDED READING IN ENGLISH FOR ADVANCED PLACEMENT PROGRAMS IN LATIN. THE LIST IS DIVIDED INTO TWO $500 GROUPS, SO THAT FOR CONVENIENCE IN…

  16. Expanding the Scope of Advanced Placement Classes

    ERIC Educational Resources Information Center

    Lim, Victoria

    2008-01-01

    Dr. Paul Dosal of the University of South Florida is not impressed with the way most high school students learn about Latin American history. Dosal believes an advanced placement course in the subject will change that. He's the executive director of ENLACE Florida, a statewide network funded by the W.K. Kellogg Foundation, designed to increase the…

  17. Introduction. Teaching Advanced Placement Human Geography.

    ERIC Educational Resources Information Center

    Murphy, Alexander B.

    2000-01-01

    Introduces this special issue of "Journal of Geography" focusing on the teaching of Advanced Placement (AP) human geography. States that essays were developed by members of the AP Human Geography Development Committee focusing on areas in the human geography course outline which are included in the appendix. (CMK)

  18. Writing Strategies for Advanced Placement European History.

    ERIC Educational Resources Information Center

    Young, Jacqueline

    This guide to effective writing strategies is based on three ideas that provide motivation for writing skills development in an advanced placement history class: students learn to write by writing; problem essays are more effective in developing writing skills than topic essays; and writing is a learning tool. Stressing that writing practice is…

  19. Literary Archetypes. Advanced Placement English Curriculum Guide.

    ERIC Educational Resources Information Center

    Anne Arundel County Public Schools, Annapolis, MD.

    Providing students with the opportunity to earn college credit while still in high school, the Advanced Placement English course described in this guide is designed to help students (1) want to choose from a wide range of literature for independent reading; (2) develop a critical awareness about literature; (3) recognize connections among works of…

  20. Advanced Placement: Model Policy Components. Policy Analysis

    ERIC Educational Resources Information Center

    Zinth, Jennifer

    2016-01-01

    Advanced Placement (AP), launched in 1955 by the College Board as a program to offer gifted high school students the opportunity to complete entry-level college coursework, has since expanded to encourage a broader array of students to tackle challenging content. This Education Commission of the State's Policy Analysis identifies key components of…

  1. Advanced Placement Courses Are Not for Everyone.

    ERIC Educational Resources Information Center

    Blagaich, Pete

    1999-01-01

    Demonstrates that Advanced Placement (AP) courses may not be appropriate for every student. Discusses the process of selecting students for AP U.S. history. Criteria include an application, summer sessions, and evidence of motivation to excel in the program. Considers the effects of this policy. (CMK)

  2. Photoelectron Spectroscopy in Advanced Placement Chemistry

    ERIC Educational Resources Information Center

    Benigna, James

    2014-01-01

    Photoelectron spectroscopy (PES) is a new addition to the Advanced Placement (AP) Chemistry curriculum. This article explains the rationale for its inclusion, an overview of how the PES instrument records data, how the data can be analyzed, and how to include PES data in the course. Sample assessment items and analysis are included, as well as…

  3. Honors and Advanced Placement Chemistry Courses.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 1983

    1983-01-01

    Summarizes papers and minipapers on honors and advanced placement (AP) chemistry courses presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). Advantages/disadvantages of AP chemistry, high school/college courses, and grouping all chemistry students in one class were among the topics discussed. (JN)

  4. Predicting success on the Advanced Placement Biology Examination

    NASA Astrophysics Data System (ADS)

    Shepherd, Lesa Hanlin

    Four hundred sixty students in four public high schools were used as subjects to determine which of eleven academic and demographic factors studied were significant predictors of success for the Advanced Placement Biology Examination. Factors studied were attendance, class rank, gender, grade level at the time of the examination, grade point average, level of prerequisite biology course, number of Advanced Placement Examinations taken in the year prior to the Advanced Placement Biology Examination, number of Advanced Placement Examinations taken in the same year as the Advanced Placement Biology Examination, proposed major in college, race, and SAT mathematics, verbal, and combined score. Significant relationships were found to exist between the Advanced Placement Biology Examination score and attendance, class rank, gender, grade level at the time of the Advanced Placement Biology Examination, grade point average, number of Advanced Placement Examinations taken in the year prior to the Advanced Placement Biology Examination, number of Advanced Placement Examinations taken in the same year as the Advanced Placement Biology Examination, race, and SAT scores. Significant relationships were not found to exist between Advanced Placement Biology Examination score and level prerequisite biology course and Advanced Placement Biology Examination score and proposed major in college. A multiple regression showed the best combination of predictors to be attendance, SAT verbal score, and SAT mathematics score. Discriminant analysis showed the variables in this study to be good predictors of whether the student would pass the Advanced Placement Biology Examination (score a 3, 4, or 5) or fail the Advanced Placement Biology Examination (score a 1 or 2). These results demonstrated that significant predictors for the Advanced Placement Biology Examination do exist and can be used to assist in the prediction of scores, prediction of passing or failing, the identification of

  5. Advanced Placement Chemistry: A Feasible, Alternative Approach to Advanced Placement Chemistry Labs.

    ERIC Educational Resources Information Center

    Bergmeier, Brian D.

    1984-01-01

    Discusses two factors to consider when initiating advanced placement (AP) chemistry, namely, the quality of those teaching the program and the time necessary to teach the relevant concepts. Suggests offering laboratory sessions during evening hours as an alternative to traditional daytime arrangements for laboratory blocks. (JN)

  6. Advanced Placement Program: Delaware Profile 1988-89.

    ERIC Educational Resources Information Center

    White, Carole D.

    The major objectives and benefits of the Advanced Placement Program (APP) are summarized, and data specific to Delaware are compared to national statistics about advanced placement (AP) courses in high schools. School participation in the APP is considered an indicator of academic success by educators and policy makers. The extent to which…

  7. AP: A Critical Examination of the Advanced Placement Program

    ERIC Educational Resources Information Center

    Sadler, Philip M.; Sonnert, Gerhard; Tai, Robert; Klopfenstein, Kirstin

    2016-01-01

    The Advanced Placement (AP) program was created to enhance the experience of gifted students as they transition from high school to college. "AP: A Critical Examination of the Advanced Placement Program," edited by Philip M. Sadler, Gerhard Sonnert, Robert Tai, and Kirstin Klopfenstein (2010, Harvard Education Press), questions the…

  8. Advanced Placement Chemistry: Project Advance and the Advanced Placement Program: A Comparison of Students' Performance on the AP Chemistry Examination.

    ERIC Educational Resources Information Center

    Mercurio, Joseph; And Others

    1984-01-01

    Compared performance of Syracuse University Project Advance (PA) chemistry students (N=35) with advanced placement (AP) candidates on the AP chemistry examination. PA students scored slightly above the national average on the examination, and students who performed well (B or better) in AP chemistry also did well on the examination. (JN)

  9. Thermal Testing of Tow-Placed, Variable Stiffness Panels

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Guerdal, Zafer

    2001-01-01

    Commercial systems for precise placement of pre-preg composite tows are enabling technology that allows fabrication of advanced composite structures in which the tows may be precisely laid down along curvilinear paths within a given ply. For laminates with curvilinear tow paths, the fiber orientation angle varies continuously throughout the laminate, and is not required to be straight and parallel in each ply as in conventional composite laminates. Hence, the stiffness properties vary as a function of location in the laminate, and the associated composite structure is called a "variable stiffness" composite structure.

  10. Technological advances for PICC placement and management.

    PubMed

    Pettit, Janet

    2007-06-01

    Placement of a peripherally inserted central catheter (PICC) is often complicated by the infant's small size and previous use of the peripheral veins, making the traditional means of insertion inadequate. New techniques and technologies, previously reserved for pediatric and adult patients, are now available for use in neonates and can enhance the practice of neonatal PICC teams. The modified Seldinger technique allows insertion of the PICC via smaller peripheral veins while decreasing venous trauma and enhancing the rate of successful placement. A second useful technique, the catheter exchange procedure, allows insertion of a new catheter within the same vein when complications such as occlusion, breakage, or inappropriate position occur and require removal of the currently dwelling PICC. Clinicians caring for neonates and infants must continually update their knowledge and skill by incorporating new techniques into their practice.

  11. Advanced Placement and International Baccalaureate Examination Results in Texas, 2000.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin. Office of Policy Planning and Research.

    The participation and performance of 11th- and 12th-grade Texas public school district students on the College Entrance Examination Board's Advanced Placement and International Baccalaureate Organisation's programs during the 1999-2000 school year were studied. Results show the largest 1-year gains to date in the number of Texas Advanced Placement…

  12. AP: A Critical Examination of the Advanced Placement Program

    ERIC Educational Resources Information Center

    Sadler, Philip M., Ed.; Sonnert, Gerhard, Ed.; Tai, Robert H., Ed.; Klopfenstein, Kristin, Ed.

    2010-01-01

    With an annual yearly growth rate of 9.3 percent over the last two decades, Advanced Placement courses have become a juggernaut in American high school education. AP courses are routinely perceived as an indicator of educational rigor, and many schools push to enroll low-income or minority students in these courses in the hope of preparing them…

  13. The Introduction of the Advanced Placement Examination in Political Science.

    ERIC Educational Resources Information Center

    Lazer, Stephen

    1988-01-01

    Discusses the format and results of the first Advanced Placement (AP) Government and Politics Examinations given by high schools in May 1987. Findings show the need for further training of AP teachers, improved instruction, and increased student interest in political science. Provides ordering information for two AP guides to assist political…

  14. Gifted Spanish Speaking English Learners' Participation in Advanced Placement Programs

    ERIC Educational Resources Information Center

    Torres, Luz Adriana

    2010-01-01

    This qualitative study sought to uncover the contextual factors of the schooling process that affect the enrollment of gifted Spanish speaking English Learners (ELs) in Advanced Placement (AP) courses. In addition, this study investigated the perceptions of gifted Spanish speaking ELs toward AP courses and how these perceptions might affect their…

  15. Advanced Placement Human Geography: The First Five Years

    ERIC Educational Resources Information Center

    Gray, Paul T., Jr.; Hidlebrant, Barbara S.; Strauss, Tim R.

    2006-01-01

    Advanced Placement Human Geography (APHG) has grown steadily from 3,272 tests at the first test administration in 2001 to 14,139 tests in 2005. This paper examines the dynamics of growth throughout the United States through numbers of students and numbers of high schools involved in the program. APHG is discussed relative to the establishment of…

  16. 75 FR 75666 - Advanced Placement (AP) Test Fee Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-06

    ... Advanced Placement (AP) Test Fee Program AGENCY: Office of Elementary and Secondary Education (OESE), Department of Education. ACTION: Notice reopening the AP Test Fee fiscal year (FY) 2011 competition. SUMMARY... applications for the AP Test Fee FY 2011 competition. That notice established a November 17, 2010 deadline...

  17. Advanced Placement Course Enrollment and School-Level Characteristics

    ERIC Educational Resources Information Center

    Barnard-Brak, Lucy; McGaha-Garnett, Valerie; Burley, Hansel

    2011-01-01

    The current study examined access to Advanced Placement (AP) courses as a function of these school characteristics (e.g., percentage of ethnic minority and lower socioeconomic status) and then examined AP course enrollment as a function of both access to AP courses and these school characteristics. Using structural equation modeling techniques,…

  18. Advanced Placement and Rural Schools: Access, Success, and Exploring Alternatives

    ERIC Educational Resources Information Center

    Gagnon, Douglas J.; Mattingly, Marybeth J.

    2016-01-01

    Completing Advanced Placement (AP) coursework is an important part of the selective college admissions process, and access to AP coursework can be viewed as a measure of equal opportunity. Relatively little research has fully examined how access to AP coursework is mediated by school characteristics. Rural schools are at a particular disadvantage…

  19. Conceptualizing a Framework for Advanced Placement Statistics Teaching Knowledge

    ERIC Educational Resources Information Center

    Haines, Brenna

    2015-01-01

    The purpose of this article is to sketch a conceptualization of a framework for Advanced Placement (AP) Statistics Teaching Knowledge. Recent research continues to problematize the lack of knowledge and preparation among secondary level statistics teachers. The College Board's AP Statistics course continues to grow and gain popularity, but is a…

  20. Cities and Urban Land Use in Advanced Placement Human Geography.

    ERIC Educational Resources Information Center

    Ford, Larry R.

    2000-01-01

    Discusses the cities and urban land use section of the Advanced Placement (AP) human geography course, focusing on the: (1) definitions of urbanism; (2) origin and evolution of cities; (3) functional character of contemporary cities; (4) built environment and social space; and (5) responses to urban growth. (CMK)

  1. Beginning an Advanced Placement Music Course. Edition Y.

    ERIC Educational Resources Information Center

    Thomson, William; And Others

    The College Entrance Examination Board has prepared this publication to help secondary school teachers develop Advanced Placement (AP) courses in music. The discussion of strategy recommendations, reading materials, and record collections should be adapted to suit local preferences and individual skills. An opening section of general remarks…

  2. Advanced Placement Exam Results, 1998-99. Measuring Up.

    ERIC Educational Resources Information Center

    Bernholc, Alissa; Baenen, Nancy; Howell, Toni

    The Advanced Placement (AP) Program allows high school students to learn subjects at a college level of difficulty. Students may receive college credit if they earn a high enough score on the AP examination typically taken at the end of an AP course. This report describes the participation and achievement of AP students in the Wake County Public…

  3. Advanced Placement United States History: A Student's Perspective.

    ERIC Educational Resources Information Center

    Neutuch, Eric

    1999-01-01

    Reflects on the experience of being in an Advanced Placement (AP) U.S. history course in high school. Stresses that the intent of the course was only to prepare students to score well on the AP examination. Asserts that the course should have aimed beyond teaching to the test. (CMK)

  4. Beginning an Advanced Placement Chemistry Course, Edition Y.

    ERIC Educational Resources Information Center

    Fornoff, Frank, Comp.

    This publication is intended to aid in the planning and implementation of Advanced Placement (AP) chemistry courses. Included are reports from high schools that have established such courses concerning costs, facilities, and instructional requirements. Also included are the free-response sections of the 1974 and 1975 AP Chemistry Examination,…

  5. Surviving a Midlife Crisis: Advanced Placement Turns Fifty

    ERIC Educational Resources Information Center

    Mollison, Andrew

    2006-01-01

    In 1956, 1,220 college-bound juniors and seniors in 104 American high schools took the first Advanced Placement (AP) exams conducted by the Educational Testing Service for the College Board. The AP program was unabashedly elitist and designed to fortify the education of the nation's future leaders in anticipation of Cold War national security…

  6. The Effect of the Advanced Placement Training and Incentive Program on Increasing Enrollment and Performance on Advanced Placement Science Exams

    ERIC Educational Resources Information Center

    Ramsey, Susan Brady

    2012-01-01

    The purpose of this study is to examine the effectiveness of the National Math and Science Initiative's Advanced Placement Training and Incentive Program (APTIP) on the number of students taking AP science courses and their performance. The study evaluated 39 schools over a six-year period in six states that participate in the APTIP. The…

  7. Materials and Area of Study for Advanced Placement Program in American History.

    ERIC Educational Resources Information Center

    Santos, Peter A.

    This paper describes and evaluates benefits of advanced placement programs and identifies materials which can help high school history classroom teachers develop effective advanced placement programs. An advanced placement program is defined as a program which requires a student to do extensive research and writing throughout the school year.…

  8. Advancing Excellence in Urban Schools: A Report on Advanced Placement Examinations in the Great City Schools.

    ERIC Educational Resources Information Center

    Eisner, Caroline, Ed.

    This is the first comprehensive study to examine Advanced Placement (AP) course-taking patterns and subject test results in the nation's urban schools. This study investigates both Great City Schools' (GCS) AP scores and scores for a national sample of test takers. The GCS data set includes 58 large urban public school districts. The primary…

  9. CEEB Advanced Placement Mathematics Examination Results and Performance in First-Quarter UW Calculus Course.

    ERIC Educational Resources Information Center

    de Wolf, Virginia A.

    Freshmen placed into the second or third quarter of the first year calculus sequence at the University of Washington were studied. Two major findings were: freshmen eligible for advanced placement earned mean mathematics Grade Point Averages (GPAs) which were quite high; and advanced placement students earned mean mathematics GPAs substantially…

  10. Her Physics, His Physics: Gender Issues in Israeli Advanced Placement Physics Classes.

    ERIC Educational Resources Information Center

    Zohar, Anat; Sela, David

    2003-01-01

    Investigates gender issues in Israeli advanced placement physics classes. Analyzes matriculation exam scores from approximately 400 high schools over 12 years. Conducts semi-constructed interviews with 50 advanced placement physics students (25 girls and 25 boys). Discusses changes in the ratio of girls, performance, and factors that are…

  11. Examining Advanced Placement Program Access and Equity for Low-Income, Latino, and English Language Learners

    ERIC Educational Resources Information Center

    Jimenez-Castellanos, Oscar

    2008-01-01

    The Advanced Placement (AP) program was initiated during the early 1950's in response to growing concerns regarding the educational needs of high ability secondary school students. The Advanced Placement "Status Quo" (AP Status Quo) framework suggests that there has been an emphasis on preparing a few students while excluding the majority of…

  12. 77 FR 8848 - Application for New Awards; Advanced Placement (AP) Test Fee Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... Application for New Awards; Advanced Placement (AP) Test Fee Program AGENCY: Office of Elementary and Secondary Education, Department of Education. ACTION: Notice. Overview Information: Advanced Placement Test.... Full Text of Announcement I. Funding Opportunity Description Purpose of Program: The AP Test...

  13. 78 FR 19691 - Applications for New Awards; Advanced Placement (AP) Test Fee Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ... Applications for New Awards; Advanced Placement (AP) Test Fee Program AGENCY: Office of Elementary and Secondary Education, Department of Education. ACTION: Notice. Overview Information Advanced Placement Test... Announcement I. Funding Opportunity Description Purpose of Program: The AP Test Fee program awards grants...

  14. Advanced Placement Academy: Case Study of a Program within a School

    ERIC Educational Resources Information Center

    Swanson, Julie Dingle; Nagy, Steven

    2014-01-01

    The focus of this study was the first year of implementation of the Advanced Placement Academy (APA), a program within a high school providing honors and Advanced Placement coursework for high-ability African American students with previously limited access to rigorous courses. The qualitative investigation explores practical solutions from…

  15. The Disappearing Continent: A Critique of the Revised Advanced Placement European History Examination

    ERIC Educational Resources Information Center

    Randall, David

    2016-01-01

    This document extends the National Association of Scholars' (NAS's) critique of the College Board from Advanced Placement U.S. History (APUSH) to Advanced Placement European History (APEH). The College Board distorts APEH in the same way that it distorted the first version of APUSH. The traditional history of Europe tells how Europeans, uniquely,…

  16. A Critical Investigation of Advanced Placement U.S. History Textbooks

    ERIC Educational Resources Information Center

    Cramer, Gregory J.

    2012-01-01

    This dissertation critically investigates how Advanced Placement (AP) U.S. History textbooks portray key events in Latino/a history. The investigation is made in light of claims made by the College Board, the ACLU, scholars, and federal and state governments that the Advanced Placement program is the path to educational equity for Latino/a…

  17. Advanced Placement U.S. History: What Happens after the Examination?

    ERIC Educational Resources Information Center

    Henry, Michael

    1991-01-01

    Discusses a survey of 56 advanced placement (AP) U.S. history teachers. Explores the scope of AP history and types of posttest activities used after Advanced Placement examinations. Concludes that public school courses developed more deeply into post-1960 events than the private schools did. Describes movies, debates, simulations, and local…

  18. Hispanic Student Performance on Advanced Placement Exams: A Multiyear, National Investigation

    ERIC Educational Resources Information Center

    Jara, Teresa Dianne

    2013-01-01

    Purpose: The purpose of this study was to analyze the Advanced Placement exams that Hispanic students complete and to compare their overall performance with the performance of White students from 2000 to 2012. A second purpose was to determine which Advanced Placement exams were the most difficult exams for Hispanic students and which Advanced…

  19. A Mixed Methods Approach to Examining an Advanced Placement Program in One Connecticut Public School District

    ERIC Educational Resources Information Center

    Docimo, Chelsey L.

    2013-01-01

    The purpose of this eleventh grade Advanced Placement (AP) program study was to determine factors associated with AP placement and subsequent student performance. This research was considered to be a mixed methods case study with elements of arrested action research. One hundred and twenty-four students, four guidance counselors, three AP…

  20. The effect of the Advanced Placement Training and Incentive Program on increasing enrollment and performance on Advanced Placement science exams

    NASA Astrophysics Data System (ADS)

    Ramsey, Susan Brady

    The purpose of this study is to examine the effectiveness of the National Math and Science Initiative's Advanced Placement Training and Incentive Program (APTIP) on the number of students taking AP science courses and their performance. The study evaluated 39 schools over a six-year period in six states that participate in the APTIP. The National Math and Science Initiative provided data for cohort I. A general linear model for repeated measures was used to evaluate the data. Data was evaluated three years prior to the intervention and three years during the intervention, which will actually continue for two more years (2012 and 2013) since cohort I schools were awarded five years of support. Students in APTIP schools enrolled in more AP science exams (AP Biology, AP Chemistry, AP Environmental Science, and AP Physics-B) over the course of the intervention. The quantity of students earning qualifying scores increased during the intervention years. APTIP is a multi-tiered program that includes seven days of teacher training, three six-hour student prep sessions, school equipment, reduced exam fees, and monetary incentives for students and teachers. This program positively impacted the quantity of enrollment and qualifying scores during the three years evaluated in this study. Increases in the number of female and African American students' test takers their and qualifying scores were seen in all three years of the APTIP intervention. This study supports the premise that the first step to increasing the Science, technology, engineering, and math (STEM) pipeline is giving access to advanced courses to more students in high schools.

  1. What Do You Mean You Don't Do Advanced Placement?: Confessions of an Educational Heretic.

    ERIC Educational Resources Information Center

    Briley, Ron

    2000-01-01

    Explains why Advanced Placement courses are not offered at Sandia Preparatory School, a college preparatory school located in Albuquerque, New Mexico. Focuses on the school mission, overall philosophy, and how this relates to the history classroom in particular. (CMK)

  2. Advanced Placement and International Baccalaureate: Do They Deserve Gold Star Status?

    ERIC Educational Resources Information Center

    Byrd, Sheila

    2007-01-01

    For many people committed to strong academic standards, the "advanced" high school courses offered through the College Board's Advanced Placement program and, increasingly, the Diploma Programme of the International Baccalaureate Organisation (IBO) represent the curricular gold standard for secondary education. Admissions directors and…

  3. The Influence of Advanced Placement Enrollment on High School GPA and Class Rank: Implications for School Administrators

    ERIC Educational Resources Information Center

    Wehde-Roddiger, Christina, Trevino, Rolando; Anderson, Pamela; Arrambide, Teresa; O'Conor, Juana; Onwuegbuzie, Anthony J.

    2012-01-01

    As high schools offer more pre-Advanced Placement (pre-AP) and Advanced Placement (AP) courses to prepare students for college academics, students often are given quality grade point average (GPA) points to help compensate for the rigorous curriculum. In states where class ranking determines automatic university admission, fluctuations of class…

  4. The School Counselor's Role in Addressing the Advanced Placement Equity and Excellence Gap for African-American Students

    ERIC Educational Resources Information Center

    Davis, Pamela; Davis, Michael P.; Mobley, Jerry A.

    2014-01-01

    This study describes the collaboration among a school counselor, a school counselor intern, an Advanced Placement Psychology teacher, and a counselor educator to improve African-American access to Advanced Placement (AP) coursework and increase success on the AP Psychology national examination. The team initiated a process that recruited African…

  5. What Does a Student Know Who Earns a Top Score on the Advanced Placement Chemistry Exam?

    ERIC Educational Resources Information Center

    Claesgens, Jennifer; Daubenmire, Paul L.; Scalise, Kathleen M.; Balicki, Scott; Gochyyev, Perman; Stacy, Angelica M.

    2014-01-01

    This paper compares the performance of students at a high-performing U.S. public school (n = 64) on the advanced placement (AP) chemistry exam to their performance on the ChemQuery assessment system. The AP chemistry exam was chosen because, as the National Research Council acknowledges, it is the "perceived standard of excellence and school…

  6. Advanced Placement English in a Solipsistic Era: How Structuralism Can Renew Meaning

    ERIC Educational Resources Information Center

    Rauh, John

    2014-01-01

    Advanced Placement (AP) courses within secondary English education can fail to meet the needs of gifted students in the postmodern era. Because AP courses often are standardized, despite the College Board's efforts to allow freedom in course design, gifted students, as especially attuned to discrepancies between practice and theory, are being…

  7. Placing Advanced Placement® Human Geography: Its Role in U.S. Geography Education

    ERIC Educational Resources Information Center

    Bednarz, Sarah Witham

    2016-01-01

    This article examines Advanced Placement Human Geography (AP HG) in the context of its place in efforts to reform geography education. It presents a critical analysis of the AP program and its curriculum, asserting that it represents "powerful knowledge" as conceptualized by Young. It concludes with a call for research in AP HG aligned…

  8. Maryland Ranks #1 in the Nation on Advanced Placement Exams for Participation and Performance

    ERIC Educational Resources Information Center

    Maryland State Department of Education, 2009

    2009-01-01

    Maryland public high school students outperformed all others in the nation on the rigorous Advanced Placement (AP) exams, according to the College Board's fifth annual analysis of the AP program. Maryland ranked first nationwide in the percentage of public school students scoring 3 or higher on at least one AP exam. A score of 3 or higher on the…

  9. Melodic Dictation Instruction: A Survey of Advanced Placement Music Theory Teachers

    ERIC Educational Resources Information Center

    Buonviri, Nathan O.; Paney, Andrew S.

    2015-01-01

    Based on relevant literature and recent qualitative findings, the purpose of this survey research was to identify pedagogical approaches to melodic dictation employed by Advanced Placement (AP) Music Theory teachers across the United States. The researcher-designed survey questions focused on pitch and rhythm skills, instructional resources,…

  10. Characteristics of Grosse Pointe High School Students in Advanced Placement Programs.

    ERIC Educational Resources Information Center

    Kaloger, James Heracles

    The purpose of this study was to attempt to identify those factors that influence a high school student's success on the Advanced Placement (AP) Examinations by examining and comparing the variables contained in the high school records of former AP participants. A total of 248 high school students participated in the research. The criterion for…

  11. Advanced Placement in Studio Art and Secondary Art Education Policy: Countering the Null Curriculum

    ERIC Educational Resources Information Center

    Graham, Mark A.; Sims-Gunzenhauser, Alice

    2009-01-01

    Because of education reform policy and misconceptions about artistry and artistic assessment, visual art education remains in the margins of high school education. One response to the lack of supportive arts education policy is the Advanced Placement (AP) Studio Art Program, a visual arts assessment at the high school level that engages large…

  12. Exploring the Third World: Two Interdisciplinary Units for Advanced Placement English.

    ERIC Educational Resources Information Center

    Traubitz, Nancy; Pfetsch, Cheryl

    Developed to enhance students' cultural awareness of Africa and the Far East, this guide contains both interdisciplinary and specific content curriculum materials for two course units in Advanced Placement English. These units were designed to (1) communicate the countries' rudimentary geography and history; (2) introduce the value systems,…

  13. Class of 2013 Advanced Placement and International Baccalaureate Exam Participation and Performance. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2014-01-01

    Beginning in 2006, Maryland has led the nation as the state with the highest percentage of graduates who earned one or more Advanced Placement (AP) exam scores of 3 or higher. Students in the Montgomery County Public Schools (MCPS) Class of 2013 continued to outperform students in the state of Maryland and the nation on AP examinations, based on…

  14. Class of 2012 Advanced Placement and International Baccalaureate Exam Participation and Performance. Memorandum

    ERIC Educational Resources Information Center

    Marks, Susan F.

    2013-01-01

    Students in the Montgomery County (Maryland) Public Schools (MCPS) Class of 2012 continued to outperform Maryland and the nation on Advanced Placement (AP) examinations based on the "AP Report to the Nation" released by the College Board on February 20, 2013. In 2012, 67.3 percent of MCPS graduates took one or more AP exams. A striking…

  15. The Effects of Advanced Placement and International Baccalaureate Programs on Student Achievement

    ERIC Educational Resources Information Center

    Luo, Samia Merza

    2013-01-01

    This study compared student academic achievement in two college readiness programs, Advanced Placement (AP) and International Baccalaureate (IB) and attempted to determine how well program participation predict student performance compared to variables such as SES, parent education level, GPA, gender, and SAT II scores. Finally, the research…

  16. Class of 2014 Advanced Placement and International Baccalaureate Exam Participation and Performance. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2015-01-01

    Beginning in 2006, Maryland has led the nation as the state with the highest percentage of graduates who earned one or more Advanced Placement (AP) exam scores of 3 or higher. Students in the Montgomery County (Maryland) Public Schools (MCPS) Class of 2014 continued to outperform students in the state of Maryland on AP examinations based on AP…

  17. Class of 2015 Advanced Placement and International Baccalaureate Exam Participation and Performance. Memorandum

    ERIC Educational Resources Information Center

    Navarro, Maria V.

    2016-01-01

    This memorandum describes the Advanced Placement (AP) and International Baccalaureate (IB) exams participation and performance of 2013 to 2015 public school graduates in Montgomery County Public Schools (MCPS) and the state of Maryland. The results are disaggregated by demographics and high schools. Students in the MCPS Class of 2015 continued to…

  18. A Narrow Escape: Gifted Students' Perceptions of Advanced Placement and International Baccalaureate Programs

    ERIC Educational Resources Information Center

    Hertberg-Davis, Holly; Callahan, Carolyn M.

    2008-01-01

    Although limited research exists on the appropriateness of Advanced Placement (AP) and International Baccalaureate (IB) programs for gifted secondary learners, these courses serve as the primary methods of meeting the needs of gifted students in most high schools. This qualitative study investigates how a broad range of gifted secondary students…

  19. Advanced Placement Human Geography and the Annual Meetings of the National Council for Geographic Education

    ERIC Educational Resources Information Center

    Sublett, Michael D.

    2007-01-01

    Members of the National Council for Geographic Education have been instrumental in the creation, launch, and early success of Advanced Placement Human Geography. Annual meetings of the Council have served as a forum for spreading the word about the course and its follow-up national examination and in helping teachers develop content confidence and…

  20. The Impact of Participation in the Advanced Placement Program on Students' College Admissions Test Scores

    ERIC Educational Resources Information Center

    Warne, Russell T.; Larsen, Ross; Anderson, Braydon; Odasso, Alyce J.

    2015-01-01

    The Advanced Placement (AP) program is an educational program that permits high school students to take introductory college-level courses and receive college credit by passing a standardized end-of-course exam. Data were obtained from a statewide database of 2 high school graduating cohorts (N = 90,044). We used a series of propensity score…

  1. Strategies for Increasing Advanced Placement Participation for Underrepresented Students: Barriers, Practices, and Positive Outcomes

    ERIC Educational Resources Information Center

    Flores, Sergio; Gomez, Martin O.

    2011-01-01

    Some school leaders have viewed programs such as Advanced Placement (AP) as an attractive option to resolve the ongoing achievement gap problem. However, the ongoing debate in the field about maintaining the ostensible purity of the AP program versus diluting it with program expansion has hindered the full utilization of AP classes to close the…

  2. Examining the Role of Advanced Placement[R] Exam Participation in 4-Year College Enrollment

    ERIC Educational Resources Information Center

    Chajewski, Michael; Mattern, Krista D.; Shaw, Emily J.

    2011-01-01

    The purpose of the current study was to examine the relationship between Advanced Placement (AP) exam participation and enrollment in a 4-year postsecondary institution. A positive relationship was expected given that the primary purpose of offering AP courses is to allow students to engage in college-level academic work while in high school, and…

  3. The Advanced Placement Opportunity Gap in Arizona: Access, Participation, and Success

    ERIC Educational Resources Information Center

    Cisneros, Jesus; Holloway-Libell, Jessica; Gomez, Laura M.; Corley, Kathleen M.; Powers, Jeanne M.

    2014-01-01

    Participation in Advanced Placement (AP) classes and AP test-taking are widely viewed as indicators of students' college readiness. We analyzed enrollment in AP courses and AP test outcomes in Arizona to document disparities in students' access to rigorous curricula in high school and outline some implications of these patterns for education…

  4. The Advanced Placement Program: A Case Study of One Urban High School

    ERIC Educational Resources Information Center

    Manos, Marika Elizabeth

    2010-01-01

    While Advanced Placement (AP) programs have been traditionally targeted toward academically prepared students, some secondary administrators make AP courses accessible to all students in order to support college readiness. The purpose of the present study is to explore how the AP program is being implemented in an urban school where many students…

  5. Measuring Success: Examining Achievement and Perceptions of Online Advanced Placement Students

    ERIC Educational Resources Information Center

    Johnston, Sharon; Barbour, Michael K.

    2013-01-01

    The purpose of the research was to compare student performance on Advanced Placement (AP) exams from 2009 to 2011 at Florida Virtual School and to explore student perceptions of their online course experience compared with the classroom-based AP experiences. The data indicated that students performed at levels comparable to the national sample but…

  6. Exploring the Utility of Advanced Placement Participation and Performance in College Admission Decisions

    ERIC Educational Resources Information Center

    Shaw, Emily J.; Marini, Jessica P.; Mattern, Krista D.

    2013-01-01

    The current study evaluated the relationship between various operationalizations of the Advanced Placement[R] (AP) exam and course information with first-year grade point average (FYGPA) in college to better understand the role of AP in college admission decisions. In particular, the incremental validity of the different AP variables, above…

  7. Measuring the Impact of Advanced Placement Failure on Students' Academic Achievement and Retention in College

    ERIC Educational Resources Information Center

    Kutchner, Wendy

    2012-01-01

    This quantitative study examined the impact that Advanced Placement (AP) coursework had on students attending college with specific emphasis on those who failed the exam. The study comprised four years of entering freshmen students between the academic years 2006-2009. The study was comprehensive in that it revealed all AP attempts regardless of…

  8. Growth and Achievement Trends of Advanced Placement (AP) Exams in American High Schools

    ERIC Educational Resources Information Center

    Judson, Eugene; Hobson, Angela

    2015-01-01

    This exploratory study examined and compared overall trends in growth and student achievement of the Advanced Placement (AP) program. Using data from the past two decades, analyses indicated there has been steady and extensive growth of AP participation, particularly among underclassmen and some minority groups. However, overall achievement, as…

  9. Ethnic and Gender Differences in Advanced Placement Exam Performance: A Multiyear National Analysis

    ERIC Educational Resources Information Center

    Holmes, Maria Alexander

    2013-01-01

    Purpose: The purpose of this study was to analyze ethnic and gender differences in Advanced Placement (AP) exam performance of U.S. high school students. Specifically, the extent to which differences exist in overall AP exam performance scores within and between four ethnic groups (i.e., Asian, Black, Hispanic, and White) was investigated. Within…

  10. Experiences of High-Achieving High School Students Who Have Taken Multiple Concurrent Advanced Placement Courses

    ERIC Educational Resources Information Center

    Milburn, Kristine M.

    2011-01-01

    Problem: An increasing number of high-achieving American high school students are enrolling in multiple Advanced Placement (AP) courses. As a result, high schools face a growing need to understand the impact of taking multiple AP courses concurrently on the social-emotional lives of high-achieving students. Procedures: This phenomenological…

  11. Advanced Placement® Summer Institute: A Survey of Florida AP® Teachers. Research Notes. RN-39

    ERIC Educational Resources Information Center

    Godfrey, Kelly E.

    2009-01-01

    Advanced Placement Program Summer Institute (APSI) courses provide teachers with an overview of the curriculum, structure, and content of specific AP courses. Attention is devoted not only to the development of curriculum but also to teaching strategies and the relationship of the course to the AP Examination. During the summers of 2006 and 2007,…

  12. Beginning an Advanced Placement German Literature (Level 3) Course. Edition Y.

    ERIC Educational Resources Information Center

    Bauer, Donna H.; And Others

    This is a supplement to the Advanced Placement (AP) German literature course description. Its aim is both to assist teachers in planning an AP German literature course and to provide experienced AP teachers with information about other successful programs. To this end, six teachers from different high schools in the U.S. provide descriptions of…

  13. Advanced Placement Strategy: A Framework for Identifying School-Level Barriers to AP Success. Policy Brief

    ERIC Educational Resources Information Center

    Batiwalla, Mary

    2014-01-01

    In 2013, Tennessee counted nearly 7,000 students in the senior cohort whose academic skills when they entered high school suggested they were on track to earn college credits through Advanced Placement (AP) exams. Yet just over half of these students actually graduated with an AP credit, and less than a third of the economically disadvantaged…

  14. The Advanced Placement English Program in Salt Lake and Granite School Districts.

    ERIC Educational Resources Information Center

    Stratopoulos, Irene Chachas

    The main purposes in examining and evaluating the Advanced Placement English Program in Salt Lake and Granite School Districts were to identify the essential curriculum features of the program, to make suggestions for curriculum improvement, and to determine whether or not the quality of the AP English Program surpassed that of the conventional…

  15. SREB States Lead the Nation in Advanced Placement and International Baccalaureate Programs. Challenge to Lead

    ERIC Educational Resources Information Center

    Collins, Crystal; Lenard, Matthew

    2007-01-01

    Advanced Placement (AP) and International Baccalaureate (IB) courses continue to receive national recognition for their rigorous curricula, and many colleges and universities award credit to students who score well on end-of-course exams in AP classes. Research suggests that students are better prepared for college if they take these courses and…

  16. SREB States Maintain Lead in Advanced Placement and International Baccalaureate Programs

    ERIC Educational Resources Information Center

    Collins, Crystal

    2009-01-01

    The Southern Regional Education Board (SREB) states lead the nation in student participation in Advanced Placement (AP) and International Baccalaureate (IB) programs. The region also continued to match the nation in the success rates of high school students on AP exams in 2008. SREB's "Challenge to Lead" Goals for Education recognize the…

  17. Perspectives on the Development and Future of Advanced Placement® Human Geography

    ERIC Educational Resources Information Center

    Hildebrant, Barbara

    2016-01-01

    Advanced Placement (AP) Human Geography faced a number of hurdles that nearly derailed the course before it launched in 2000-2001. A dedicated cadre of geography professionals and high school teachers rose to the challenge and the course remains one of the fastest growing AP courses currently offered by College Board. Seventeen readers and leaders…

  18. WCPSS Advanced Placement (AP) Results, 2010-11. D&A Report No. 11.25

    ERIC Educational Resources Information Center

    Gilleland, Kevin

    2012-01-01

    One method of delivering college-level coursework to high school students is through the Advanced Placement (AP) program. Many colleges and universities provide credit to students who earn a qualifying score on any of the 34 available AP exams offered by the College Board. All qualified comprehensive high schools in the Wake County Public School…

  19. Advanced Placement and International Baccalaureate Programs: A "Fit" for Gifted Learners?

    ERIC Educational Resources Information Center

    Hertberg-Davis, Holly; Callahan, Carolyn M.; Kyburg, Robin M.

    2006-01-01

    Although limited research exists on the appropriateness of Advanced Placement (AP) and International Baccalaureate (IB) Programs for gifted secondary learners, these courses serve as the primary methods of meeting the needs of gifted students in most high schools. This qualitative study employed a grounded theory approach to investigate how…

  20. Preparing Students for Advanced Placement Spanish Literature: Content Sequencing of the Reading Skill.

    ERIC Educational Resources Information Center

    Stein, Roger D.

    1985-01-01

    Describes a reading-skill-building curriculum that prepares students to handle the reading in the Advanced Placement Spanish Literature course, a course that treats the works of Borges, Garcia Lorca, Matute, Neruda, and Unamuno. Suggests techniques and texts that aid in the teaching of these skills. (SED)

  1. The Advanced Placement Arms Race and the Reproduction of Educational Inequality

    ERIC Educational Resources Information Center

    Klugman, Joshua

    2013-01-01

    Background: Access to Advanced Placement (AP) courses is stratified by class and race. Researchers have identified how schools serving disadvantaged students suffer from various kinds of resource deprivations, concluding that interventions are needed to equalize access to AP courses. On the other hand, the theory of Effectively Maintained…

  2. Advanced Placement European History: An Anatomy of the Essay Examination, 1956-2000

    ERIC Educational Resources Information Center

    Blackey, Robert

    2002-01-01

    The College Board's Advanced Placement European History examination has evolved over the course of its first half-century of existence in virtually all respects: the types and subject matter of questions asked (and not asked); the nature of the history those questions reflect; the number of questions both offered and to be answered, as well as how…

  3. Teacher Scaffolding of Academic Language in an Advanced Placement U.S. History Class

    ERIC Educational Resources Information Center

    Gritter, Kristine; Beers, Scott; Knaus, Robert W.

    2013-01-01

    This article examines teacher scaffolding of academic language in an Advanced Placement United States History (APUSH) course throughout a school year for one student who received a perfect score on the end of year APUSH exam. Data includes four months of observation of teacher instructional strategies to scaffold student writing and vignettes of…

  4. Teaching Advanced Placement United States History in the Urban, Minority High School: Successful Strategies.

    ERIC Educational Resources Information Center

    DiLorenzo, Robert

    1999-01-01

    Discusses teaching Advanced Placement (AP) U.S. history at an urban, minority high school. Addresses student recruitment; using a summer assignment; notetaking and the Document-Based Quiz, various teaching strategies; preparing and reviewing for the AP examination; using special events; and the importance of professional development and…

  5. Excellence, Equity, and Access: Educators' Perceptions of Students in Open Access Advanced Placement Courses

    ERIC Educational Resources Information Center

    King, Justyna Plichta

    2010-01-01

    This dissertation examines educators' perceptions regarding open access Advanced Placement (AP) program courses and their impact on non-traditional AP students in one suburban school district. The data were collected during the 2009-2010 school year through a 15-item Likert scale (and one open-ended item) survey which was disseminated during…

  6. The Challenge of Advanced Placement Partnerships in the South Texas Border Classroom

    ERIC Educational Resources Information Center

    Blackwell, Deborah L.; Pisani, Jana S.; Pisani, Michael J.

    2007-01-01

    In the year 2000, the Texas Education Agency and the Texas A&M University System teamed up to create an initiative called the University Faculty Fellows Program. Spearheaded by Texas A&M International University in Laredo, the program paired up faculty from the university with area Advanced Placement (AP) teachers in a variety of…

  7. The Oral Histories of Six African American Males in Their Ecology of Advanced Placement Biology

    ERIC Educational Resources Information Center

    Halasa, Katrina Bassam

    2012-01-01

    The major purpose of this qualitative study was to examine the past in order to understand the complex phenomenon of students engaging in science (Newman, Ridenour, Newman, & DeMarco, 2003) specifically through the oral histories of six self-identified African American males enrolled in a high school Advanced Placement Biology class and the…

  8. Collective Teacher Efficacy and Minority Enrollment in Advanced Placement and International Baccalaureate Classes

    ERIC Educational Resources Information Center

    McDowell, Mary Collier

    2009-01-01

    The purpose of this study was to determine the extent to which Collective Teacher Efficacy explained the variance in Black and Hispanic enrollment in Advanced Placement and International Baccalaureate classes. In order to achieve this purpose, survey research methodology was employed with Virginia high schools as the unit of study. Fifty-three…

  9. Science and Mathematics Advanced Placement Exams: Growth and Achievement over Time

    ERIC Educational Resources Information Center

    Judson, Eugene

    2017-01-01

    Rapid growth of Advanced Placement (AP) exams in the last 2 decades has been paralleled by national enthusiasm to promote availability and rigor of science, technology, engineering, and mathematics (STEM). Trends were examined in STEM AP to evaluate and compare growth and achievement. Analysis included individual STEM subjects and disaggregation…

  10. Developing a Plan to Support Mathematics Students with Advanced Placement Potential at Indian River High School

    ERIC Educational Resources Information Center

    Timmons, Sara J.

    2009-01-01

    One of the many goals of schools is to have each student reach his/her fullest potential. One way schools challenge the accelerated learners is through the advanced placement (AP) program. Many able students at Indian River High School (IRHS) are choosing to enroll in college prep math courses instead of enrolling in honors and AP math. When…

  11. Is Increased Access Enough? Advanced Placement Courses, Quality, and Success in Low-Income Urban Schools

    ERIC Educational Resources Information Center

    Hallett, Ronald E.; Venegas, Kristan M.

    2011-01-01

    This article combines descriptive statistics and interviews with college-bound high school students to explore the connection between increased access and academic quality of Advanced Placement (AP) courses in low-income urban high schools. Results suggest that although moderately more opportunities to take AP courses exist than in previous years,…

  12. Should a High School Adopt Advanced Placement or a Concurrent Enrollment Program? An Expected Benefit Approach

    ERIC Educational Resources Information Center

    Dutkowsky, Donald H.; Evensky, Jerry M.; Edmonds, Gerald S.

    2009-01-01

    This article provides an explicit framework for evaluating the expected benefit to college-bound students of courses offered by Advanced Placement (AP) versus concurrent enrollment programs (CEP). District personnel can use it to assess the relative merits of these programs, given the characteristics of their students, in deciding which model to…

  13. Student Access to Advanced Placement[R] (AP[R]) Coursework: Principals' Beliefs and Practices

    ERIC Educational Resources Information Center

    Wood, Steven M.

    2010-01-01

    Advanced Placement[R] (AP[R]) courses provide high school students an opportunity to be exposed to the rigors of college while they are still in high school. Since school policies play a role in the opportunities for students to pursue these courses, educational leaders must be aware of the ways in which their personal beliefs and school practices…

  14. A Validity Study of the Multiple-Choice Component of the Advanced Placement Chemistry Examination.

    ERIC Educational Resources Information Center

    Modu, Christopher C.; Taft, Hessy L.

    1982-01-01

    Compares performance of first-year general chemistry college students from 32 institutions with performance of Advanced Placement (AP) Chemistry Candidates in 1978 to provide a concurrent validity measure of the multiple-choice section of the AP chemistry examination. Average AP candidates scored significantly higher than average college students.…

  15. Engaging High School Students in Advanced Math and Science Courses for Success in College: Is Advanced Placement the Answer?

    ERIC Educational Resources Information Center

    Kelley-Kemple, Thomas; Proger, Amy; Roderick, Melissa

    2011-01-01

    The current study provides an in-depth look at Advanced Placement (AP) math and science course-taking in one school district, the Chicago Public Schools (CPS). Using quasi-experimental methods, this study examines the college outcomes of students who take AP math and science courses. Specifically, this study asks whether students who take AP math…

  16. Where the girls aren't: High school girls and advanced placement physics enrollment

    NASA Astrophysics Data System (ADS)

    Barton, Susan O'brien

    During the high school years, when many students first have some choice in course selection, research indicates that girls choose to enroll in more math and science courses, take more advanced placement courses, and take more honors courses in English, biology, chemistry, mathematics, and foreign languages than ever before. Yet, not only are boys more likely to take all of the three core science courses (biology, chemistry, and physics), boys enroll in advanced placement physics approximately three times as often as do girls. This study examines the perceptions, attitudes, and aspirations of thirty high school girls enrolled in senior-level science electives in an attempt to understand their high school science course choices, and what factors were influencing them. This is a qualitative investigation employing constructivist grounded theory methods. There are two main contributions of this study. First, it presents a new conceptual and analytical framework to investigate the problem of why some high school girls do not enroll in physics coursework. This framework is grounded in the data and is comprised of three existing feminist perspectives along the liberal/radical continuum of feminist thought. Second, this study illuminates a complex set of reasons why participants avoided high school physics (particularly advanced placement physics) coursework. These reasons emerged as three broad categories related to: (a) a lack of connectedness with physics curriculum and instruction; (b) prior negative experiences with physics and math classroom climates; and (c) future academic goals and career aspirations. Taken together, the findings of this study indicate that the problem of high school girls and physics enrollment---particularly advanced placement physics enrollment---is a problem that cannot be evaluated or considered from one perspective.

  17. Myth 19: Is Advanced Placement an Adequate Program for Gifted Students?

    ERIC Educational Resources Information Center

    Gallagher, Shelagh A.

    2009-01-01

    Is it a myth that Advanced Placement (AP) is an adequate program for gifted students? AP is so covered with myths and assumptions that it is hard to get a clear view of the issues. In this article, the author finds the answer about AP by looking at current realties. First, AP is hard for gifted students to avoid. Second, AP never was a program…

  18. Advanced Placement Results, 2013-14. Measuring Up. D&A Report No.15.01

    ERIC Educational Resources Information Center

    Gilleland, Kevin; Muli, Juliana

    2015-01-01

    Advanced Placement (AP) outcomes for Wake County Public School System (WCPSS) students have continued an upward trend for over 18 years, out-performing the state and the nation in all measures. In 2013-14 there were 13,757 exams taken by 6,955 WCPSS test-takers with almost 76% of the exams resulting in scores at or above 3, outperforming Guilford…

  19. Evaluation of a Highly Anticlastic Panel with Tow Overlaps

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Gurdal, Zafer

    2007-01-01

    A rectangular, variable-stiffness panel with tow overlaps was manufactured using an advanced tow placement machine. The cured panel had large anticlastic imperfections, with measured amplitudes of over two times the average panel thickness. These imperfections were not due to the overall steered-fiber layup or the tow overlaps, but instead resulted from local asymmetries in the laminate that were caused by a manufacturing oversight. In the nominal panel layup, fiber angles vary linearly from 60 degrees on the panel axial centerline to 30 degrees on the parallel edges. A geometrically nonlinear analysis was performed with a -280 degree Fahrenheit thermal load to simulate the postcure cooldown to room temperature. The predicted geometric imperfections correlated well with the measured panel shape. Unique structural test fixtures were then developed which greatly reduced these imperfections, but they also caused prestresses in the panel. Surface imperfections measured after the panel was installed in the test fixtures were used with nonlinear finite element analyses to predict these fixturing-induced prestresses. These prestresses were also included in structural analyses of panel end compression to failure, and the analytical results compared well with test data when both geometric and material nonlinearities were included.

  20. Is a 3 a C?: The Reliability of the Advanced Placement United States History Test for College Credit.

    ERIC Educational Resources Information Center

    Hyser, Raymond M.

    1999-01-01

    Explores the development of the Advanced Placement (AP) U.S. history test and reviews its grading process for consistency and fairness. Examines the efforts taken to ensure compatibility with college-level U.S. history survey courses. (CMK)

  1. Reaching the Next Stephen Hawking: Five Ways to Help Students with Disabilities in Advanced Placement Science Classes

    ERIC Educational Resources Information Center

    Howard, Lori A.; Potts, Elizabeth A.; Linz, Ed

    2013-01-01

    As the federal government encourages all students to attempt advanced math and science courses, more students with disabilities are enrolling in Advanced Placement (AP) science classes. AP science teachers can better serve these students by understanding the various types of disabilities (whether physical, learning, emotional, or behavioral),…

  2. Access to Success:Patterns of Advanced Placement Participation in U.S. High Schools. Policy Information Report

    ERIC Educational Resources Information Center

    Handwerk, Philip; Tognatta, Namrata; Coley, Richard J.; Gitomer, Drew H.

    2008-01-01

    Providing high school students access to advanced coursework has long been considered an important means of preparing students for success after high school. This study merges data from College Board's Advanced Placement (AP) program for the 2003-2004 school year with data from the U.S. Department of Education for all U.S. public high schools to…

  3. Impact of Advanced Grade 8 U.S. History on Participation and Performance in Advanced Placement Social Studies Courses in Grade 9

    ERIC Educational Resources Information Center

    Maina, Nyambura Susan

    2015-01-01

    At the request of the Office of Curriculum and Instructional Programs, the Office of Shared Accountability examined the impact of offering Advanced Grade 8 U.S. History on enrollment and performance in Advanced Placement (AP) social studies courses in Grade 9. The study compared Grade 9 enrollment and performance in AP U.S. History or AP U.S.…

  4. College Credit Earned in High School: Comparing Student Performance in Project Advance and Advanced Placement.

    ERIC Educational Resources Information Center

    Mercurio, Joseph A.; And Others

    1983-01-01

    Syracuse University's Project Advance (one of the first high school college cooperative programs in the United States through which college courses, taught in high schools by high school faculty, are taken for college credit) is described. (MLW)

  5. Carbon Fiber TOW Angle Determination Using Microwave Reflectometry

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Moore, Jason P.; Juarez, Peter D.

    2016-01-01

    NASA's Advanced Composites Project is investigating technologies that increase automated remote inspection of aircraft composite structures. Therefore, microwave Frequency Domain Reflectometry (FDR) is being investigated as a method of enabling rapid remote inspection of angular orientation of the tow using microwave radiation. This work will present preliminary data demonstrating that frequency shifts in the reflection spectrum of a carbon fiber tow sample are indicative of the angle of the tow with respect to an interrogating antenna's linear polarized output.

  6. Optimization of Elastically Tailored Tow-Placed Plates with Holes

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.; Tatting, Brian F.; Guerdal, Zafer

    2003-01-01

    Elastic stiffness tailoring of laminated composite panels by allowing the fibers to curve within the plane of the laminate is a design concept that has been demonstrated to be both beneficial and practical. The objective of the present paper is to demonstrate the effectiveness of stiffness tailoring through the use of curvilinear fibers to reduce stress concentrations around the hole and improve the load carrying capability of panels. Preliminary panel designs that are to be manufactured and tested were determined through design studies for flat plates without holes under axial compression using an optimization program. These candidate designs were then analyzed with finite element models that accurately reflect the test conditions and geometries in order to decide upon the final designs for manufacture and testing. An advanced tow-placement machine is used to manufacture the test panels with varying fiber orientation angles. A total of six large panels measuring three feet by six feet, each of which is used to produce four specimens with or without holes, are fabricated. The panels were machined into specimens with holes and tested at NASA Langley Research Center. Buckling response and failure of panels without holes and with two different hole dimensions are presented. Buckling and failure loads of tow-steered specimens are significantly greater than the buckling and failure loads of traditional straight-fiber specimens.

  7. Four Years Later: A Longitudinal Study of Advanced Placement Students in College. College Board Report No. 86-2.

    ERIC Educational Resources Information Center

    Willingham, Warren W.; Morris, Margaret

    The college careers of students who had participated in the Advanced Placement Program (AP) in secondary school were studied, based on extensive information on 4,814 students who participated in the Personal Qualities Project, a longitudinal study in nine colleges and universities. The project included information on 1,115 AP and 3,699 non-AP…

  8. Online Advanced Placement Courses: Experiences of Rural and Low-Income High School Students. WCALO Special Studies.

    ERIC Educational Resources Information Center

    Marcel, Kathleen W.

    A study examined rural, low-income students' experiences with online advanced placement (AP) courses. Interviews were conducted with 30 students, their mentors, and school administrators at four rural high schools in two Western states; 25 students were low-income. Positive comments about the online experience mentioned interaction with other…

  9. Early College Academic Performance: Studying the Effects of Earning College Credits from Advanced Placement and Dual Enrollment

    ERIC Educational Resources Information Center

    Williams, Jermaine F.

    2010-01-01

    This quantitative study examined the impact of Advanced Placement (AP) and Dual Enrollment (DE) on early college academic performance by analyzing and comparing first year and sophomore year persistence rates and grade point averages (GPAs) of four student cohorts who began their education at a large urban research I university in fall 2007. These…

  10. Assessment of Advanced Placement Participation and University Academic Success in the First Semester: Controlling for Selected High School Academic Abilities

    ERIC Educational Resources Information Center

    Scott, Timothy P.; Tolson, Homer; Lee, Yi-Hsuan

    2010-01-01

    The College Board Advanced Placement Program allows high school students to take college-level courses and if an appropriate score on an exam is received, college credit is earned. While the program has had its detractors (access in rural and inner-city schools, lack of diversity, pre-selection of talented students, poor articulation with actual…

  11. Sex Differences in the Relationship of Advanced Placement Essay and Multiple-Choice Scores to Grades in College Courses.

    ERIC Educational Resources Information Center

    Bridgeman, Brent; Lewis, Charles

    Essay and multiple-choice scores from Advanced Placement (AP) examinations in American History, European History, English Language and Composition, and Biology were matched with freshman grades in a sample of 32 colleges. Multiple-choice scores from the American History and Biology examinations were superior to essays for predicting overall grade…

  12. Advanced Placement (AP) Social Studies Teachers' Use of Academic Course Blogs as a Supplemental Resource for Student Learning

    ERIC Educational Resources Information Center

    Alper, Seth M.

    2013-01-01

    This mixed-methods study investigated the relationship between Advanced Placement (AP) social studies teachers' utilization of academic course blogs and student achievement. Simultaneously, the study examined the participating teachers' perceptions on the use of course blogs and other social media as supplemental learning resources. The…

  13. Weighting for Recognition: Accounting for Advanced Placement and Honors Courses when Calculating High School Grade Point Average

    ERIC Educational Resources Information Center

    Sadler, Philip M.; Tai, Robert H.

    2007-01-01

    Honors and advanced placement (AP) courses are commonly viewed as more demanding than standard high school offerings. Schools employ a range of methods to account for such differences when calculating grade point average and the associated rank in class for graduating students. In turn, these statistics have a sizeable impact on college admission…

  14. Effectiveness of Selected Advanced Placement Programs on the Academic Performance and College Readiness of High School Students

    ERIC Educational Resources Information Center

    Lewis, Traschell S.

    2012-01-01

    The purpose of this study was to examine the effectiveness of selected Advanced Placement (AP) programs on the academic performance and college readiness of high school students. Specifically, the researcher was concerned with ascertaining the effectiveness of social science, math, science, English, music/art and language AP programs on the…

  15. Racial Differences in the Impact of Participating in Advanced Placement Programs on Educational and Labor Market Outcomes

    ERIC Educational Resources Information Center

    Flowers, Lamont A.

    2008-01-01

    Despite the wealth of information generated in recent years regarding the benefits for students who participate in Advanced Placement (AP) programs on educational outcomes, limited research exists contrasting and comparing the differential effects of AP program participation on educational and labor market outcomes by race. However, research…

  16. The Advanced Placement Program in Pennsylvania: Implications for Policy and Practice in K-12 and Higher Education

    ERIC Educational Resources Information Center

    Liekar, Christine Y.

    2012-01-01

    Since the time of Sputnik, American educators and policymakers have recognized the need to raise expectations by increasing rigor in high schools across the United States. Copious studies attest to the fact that students who take Advanced Placement coursework experience success in college (Adelman, 1999; Camara, 2003; College Board, 2005;…

  17. Advanced Placement versus Dual Enrollment: Making the Best Choice for College Selection, Persistence, Early Success, and Time to Completion

    ERIC Educational Resources Information Center

    Gruman, Daniel H.

    2013-01-01

    A substantial amount of research examines the benefits of high school college-credit attainment programs against non-participation. The growth in popularity of these programs, particularly Advanced Placement (AP) and dual enrollment (DE), has them competing against one another for student attention. However, students, schools, and policymakers do…

  18. High School Advanced Placement and Student Performance in College: STEM Majors, Non-STEM Majors, and Gender Differences

    ERIC Educational Resources Information Center

    Ackerman, Phillip L.; Kanfer, Ruth; Calderwood, Charles

    2013-01-01

    Background/Context: The past few decades have seen an explosive growth in high-school student participation in the Advanced Placement program® (AP), with nearly two million exams completed in 2011. Traditionally, universities have considered AP enrollment as an indicator for predicting academic success during the admission process. However, AP…

  19. 77 FR 24480 - Application for New Awards; Advanced Placement (AP) Test Fee Program-Reopening the AP Test Fee...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ... Application for New Awards; Advanced Placement (AP) Test Fee Program--Reopening the AP Test Fee Fiscal Year.... ACTION: Notice reopening the AP Test Fee fiscal year 2012 competition. Catalog of Federal Domestic... 8848) a notice inviting applications for the AP Test Fee fiscal year (FY) 2012 competition (February...

  20. An Investigation of College Students' Perceptions of Advanced Placement® Courses. Research Note 2013-2

    ERIC Educational Resources Information Center

    Cooney, Siobhan M.; McKillip, Mary E. M.; Smith, Kara

    2013-01-01

    The present study investigates how current college students perceive their experiences in high school Advanced Placement Program (AP) courses. The goal of this research was twofold: We wanted to not only add to the existing literature on outcomes for AP students but also investigate possible benefits for students without success (i.e., a score of…

  1. A Phenomenological Study of How High School Advanced Placement Classes Prepared First-Generation College Students for Postsecondary Education

    ERIC Educational Resources Information Center

    Snyder, Scott

    2013-01-01

    This study investigated the lived experiences of first-generation college students and the perceived influence of taking high school Advanced Placement (AP) courses on their college education. The following research questions were addressed: (a) what motivated students to consider going to college, (b) what was their experience in taking AP…

  2. The Advanced Placement Program Benefits Mainly Well-Prepared Students Who Pass AP Exams. Issues in College Readiness

    ERIC Educational Resources Information Center

    National Center for Educational Achievement, 2010

    2010-01-01

    Many policymakers and education leaders have embraced the Advanced Placement (AP) Program as a tool to strengthen the high school curriculum and prepare students for college. The popularity of the AP program among these policy leaders reflects their belief that the traditional high school curriculum has often failed to provide rigorous courses…

  3. Advanced Placement English Exam Scores: A Comparison of Scores for Hispanic Students from California, Texas, and Arizona

    ERIC Educational Resources Information Center

    Koch, Bevan; Slate, John R.; Moore, George W.

    2016-01-01

    We compared the performance of Hispanic students from California, Texas, and Arizona on the two Advanced Placement (AP) English exams (i.e., English Language and Composition and English Literature and Composition) using archival data from the College Board from 1997 through 2012. Pearson chi-square tests yielded statistically significant…

  4. Determinants of Students' Success: The Role of Advanced Placement and Dual Enrollment Programs. An NCPR Working Paper

    ERIC Educational Resources Information Center

    Speroni, Cecilia

    2011-01-01

    Advanced Placement (AP) and Dual Enrollment (DE) are two programs that allow high school students to earn college credits. The recent growth of these programs has been unprecedented. However, there is little evidence that compares how they fare in terms of improving college access and success. Using data from two cohorts of all high school…

  5. "Shouldn't Everyone Know about Their Government?" An Exploration of Curricular Values in Advanced Placement Government Classes

    ERIC Educational Resources Information Center

    Krutka, Daniel G.

    2012-01-01

    Prevalent models of secondary education in the United States have tended to privilege the acquisition of knowledge of scientific disciplines that is often peripheral to the experiences of students. My Advanced Placement Government classes were no different, and this caused me to wonder whether my classes were meeting the often-stated goal of the…

  6. The Experiences of Advanced Placement and International Baccalaureate Diploma Program Participants: A Systematic Review of Qualitative Research

    ERIC Educational Resources Information Center

    Park, Kelly; Caine, Vera; Wimmer, Randolph

    2014-01-01

    Enriched high school curricula like the Advanced Placement and International Baccalaureate Diploma programs are endorsed as "pathway programs" for postsecondary-bound students. Program participation is perceived to have benefits that appeal to a broad stakeholder group of universities, administrators, teachers, students, and parents. In…

  7. A Portrait of Advanced Placement Teachers' Practices. Research Report No. 2005-7. ETS RR-05-09

    ERIC Educational Resources Information Center

    Paek, Pamela L.; Ponte, Eva; Sigel, Irv; Braun, Henry; Powers, Don

    2005-01-01

    The Advanced Placement Program® (AP®) is dedicated to providing high school students opportunities to enroll in college-level courses while in high school. The advantages of such accelerated opportunities are both financial and educational. The AP Program is available internationally. As a result of its widespread availability, considerable effort…

  8. Coping, Stress, and Job Satisfaction as Predictors of Advanced Placement Statistics Teachers' Intention to Leave the Field

    ERIC Educational Resources Information Center

    McCarthy, Christopher J.; Lambert, Richard G.; Crowe, Elizabeth W.; McCarthy, Colleen J.

    2010-01-01

    This study examined the relationship of teachers' perceptions of coping resources and demands to job satisfaction factors. Participants were 158 Advanced Placement Statistics high school teachers who completed measures of personal resources for stress prevention, classroom demands and resources, job satisfaction, and intention to leave the field…

  9. Confronting the "Acid Test": Educators' Perspectives on Expanding Access to Advanced Placement at a Diverse Florida High School

    ERIC Educational Resources Information Center

    Rowland, M. Lance; Shircliffe, Barbara J.

    2016-01-01

    This study examines educators' perspectives on accountability mandates designed to expand access to the College Board's Advanced Placement (AP) classes to traditionally underserved students at a diverse suburban high school in Florida, Palm Crest High School. Consistent with Elmore (1979), district and site-based administrators focused on the…

  10. High School Students' Attitudes and Beliefs on Using the Science Writing Heuristic in an Advanced Placement Chemistry Class

    ERIC Educational Resources Information Center

    Putti, Alice

    2011-01-01

    This paper discusses student attitudes and beliefs on using the Science Writing Heuristic (SWH) in an advanced placement (AP) chemistry classroom. During the 2007 school year, the SWH was used in a class of 24 AP chemistry students. Using a Likert-type survey, student attitudes and beliefs on the process were determined. Methods for the study are…

  11. Structural Response of Compression-Loaded, Tow-Placed, Variable Stiffness Panels

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Guerdal, Zafer; Starnes, James H., Jr.

    2002-01-01

    Results of an analytical and experimental study to characterize the structural response of two compression-loaded variable stiffness composite panels are presented and discussed. These variable stiffness panels are advanced composite structures, in which tows are laid down along precise curvilinear paths within each ply and the fiber orientation angle varies continuously throughout each ply. The panels are manufactured from AS4/977-3 graphite-epoxy pre-preg material using an advanced tow placement system. Both variable stiffness panels have the same layup, but one panel has overlapping tow bands and the other panel has a constant-thickness laminate. A baseline cross-ply panel is also analyzed and tested for comparative purposes. Tests performed on the variable stiffness panels show a linear prebuckling load-deflection response, followed by a nonlinear response to failure at loads between 4 and 53 percent greater than the baseline panel failure load. The structural response of the variable stiffness panels is also evaluated using finite element analyses. Nonlinear analyses of the variable stiffness panels are performed which include mechanical and thermal prestresses. Results from analyses that include thermal prestress conditions correlate well with measured variable stiffness panel results. The predicted response of the baseline panel also correlates well with measured results.

  12. Characteristics of Advanced Placement environmental science reading teacher participants and their perceptions of the reading as a professional development experience

    NASA Astrophysics Data System (ADS)

    Crawford, Freda M.

    Sixty percent of American high schools offer one or more Advanced Placement courses, and several thousand Advanced Placement teachers serve as Readers or graders of Advanced Placement exams each year. This study was conducted to determine the characteristics of teachers who choose to participate in Advanced Placement Environmental Science Readings and determine how these teachers view the Reading experience as a form of professional development. This study was conducted with teacher participants at the June 2004 Advanced Placement Environmental Science Reading. Sixty of the 114 teacher participants completed a survey regarding their education background, age, experience level, educational philosophy, involvement in professional development opportunities, perceptions of the professional benefits of the Reading, and the influence of the Reading experience on their pedagogical practices. Semi-structured interviews were then conducted with a subset of 18 teacher participants to determine their perceptions regarding the professional benefits of the Reading experience, its potential to serve as a professional development activity, and perceived changes in their pedagogical practices resulting from participation in the Reading process. Results indicate that APES Reading teacher participants are experienced, effective teachers from many parts of the country. These teachers participate in ongoing professional development activities, can delineate components of effective professional development, strongly believe that effective professional development occurs at the APES Reading, and report that their pedagogical practice has improved as a result of participation in the APES Reading. Considering the crucial role teachers play in the educational process, it is important to pursue this additional avenue of professional development in order to further improve APES teacher effectiveness.

  13. The oral histories of six African American males in their ecology of Advanced Placement Biology

    NASA Astrophysics Data System (ADS)

    Halasa, Katrina Bassam

    The major purpose of this qualitative study was to examine the past in order to understand the complex phenomenon of students engaging in science (Newman, Ridenour, Newman, & DeMarco, 2003) specifically through the oral histories of six self-identified African American males enrolled in a high school Advanced Placement Biology class and the oral histories about events that followed during their post high school experiences. To elucidate an understanding of this phenomenon, this research explored the ecology of African American males' descriptions of their school science, their peer school science community, their lived experiences during and after graduation, and their meso-community (Bronfenbrenner, 1979). Many minority and low-income students are less likely to enroll in rigorous courses during high school (Education Trust, 2006). This study is of utmost importance because capturing the informants' oral histories may improve rigorous science education. Many African American male students are attending urban schools with an ever growing achievement gap among their White counterparts (Norman, Ault, Bentz, & Meskimen, 2001); therefore, they are disengaging in science. As a result, African American males are underrepresented in both science careers and achievements in science (Atwater, 2000; National Science Foundation, 1994). The six oral histories highlighted the ecological factors that affected African American males regarding (1) the impact of their relationship with their mothers, (2) the understanding of personal responsibility, (3) the notion of a scientist, (4) the issue of gender being more of an obstacle than race, (5) the understanding that education is valuable, (6) the interactions and influence of relationships with others on their decisions, (7) the development of integrity through the participation in sports, (8) the ecological neighborhood environment influences an image, (9) the enrollment of Advanced Placement Biology course helped the transition

  14. "Advanced Classes? They're Only for White Kids": How One Kansas School Is Changing the Face of Honors and Advanced Placement Courses

    ERIC Educational Resources Information Center

    Kerr, Roberta

    2014-01-01

    The purpose of this study was to obtain an accurate picture of minority student enrollment in honors and advanced placement (AP) classes at Wichita (Kansas) High School East and to develop a plan of action to close the achievement gap between White and non-White students. Prior to this study there was no clear, concise data to move this discussion…

  15. The relationship between selected standardized test scores and performance in advanced placement math and science exams: Analyzing the differential effectiveness of scores for course identification and placement

    NASA Astrophysics Data System (ADS)

    Urbina, Josue N.

    There is a national need to increase the STEM-related workforce. Among factors leading towards STEM careers include the number of advanced high school mathematics and science courses students complete. Florida's enrollment patterns in STEM-related Advanced Placement (AP) courses, however, reveal that only a small percentage of students enroll into these classes. Therefore, screening tools are needed to find more students for these courses, who are academically ready, yet have not been identified. The purpose of this study was to investigate the extent to which scores from a national standardized test, Preliminary Scholastic Assessment Test/ National Merit Qualifying Test (PSAT/NMSQT), in conjunction with and compared to a state-mandated standardized test, Florida Comprehensive Assessment Test (FCAT), are related to selected AP exam performance in Seminole County Public Schools. An ex post facto correlational study was conducted using 6,189 student records from the 2010 - 2012 academic years. Multiple regression analyses using simultaneous Full Model testing showed differential moderate to strong relationships between scores in eight of the nine AP courses (i.e., Biology, Environmental Science, Chemistry, Physics B, Physics C Electrical, Physics C Mechanical, Statistics, Calculus AB and BC) examined. For example, the significant unique contribution to overall variance in AP scores was a linear combination of PSAT Math (M), Critical Reading (CR) and FCAT Reading (R) for Biology and Environmental Science. Moderate relationships for Chemistry included a linear combination of PSAT M, W (Writing) and FCAT M; a combination of FCAT M and PSAT M was most significantly associated with Calculus AB performance. These findings have implications for both research and practice. FCAT scores, in conjunction with PSAT scores, can potentially be used for specific STEM-related AP courses, as part of a systematic approach towards AP course identification and placement. For courses with

  16. Advanced placement math and science courses: Influential factors and predictors for success in college STEM majors

    NASA Astrophysics Data System (ADS)

    Hoepner, Cynthia Colon

    President Obama has recently raised awareness on the need for our nation to grow a larger pool of students with knowledge in science mathematics, engineering, and technology (STEM). Currently, while the number of women pursuing college degrees continues to rise, there remains an under-representation of women in STEM majors across the country. Although research studies offer several contributing factors that point to a higher attrition rate of women in STEM than their male counterparts, no study has investigated the role that high school advanced placement (AP) math and science courses play in preparing students for the challenges of college STEM courses. The purpose of this study was to discover which AP math and science courses and/or influential factors could encourage more students, particularly females, to consider pursuing STEM fields in college. Further, this study examined which, if any, AP math or science courses positively contribute to a student's overall preparation for college STEM courses. This retrospective study combined quantitative and qualitative research methods. The survey sample consisted of 881 UCLA female and male students pursuing STEM majors. Qualitative data was gathered from four single-gender student focus groups, two female groups (15 females) and two male groups (16 males). This study examined which AP math and science courses students took in high school, who or what influenced them to take those courses, and which particular courses influenced student's choice of STEM major and/or best prepared her/him for the challenges of STEM courses. Findings reveal that while AP math and science course-taking patterns are similar of female and male STEM students, a significant gender-gap remains in five of the eleven AP courses. Students report four main influences on their choice of AP courses; self, desire for math/science major, higher grade point average or class rank, and college admissions. Further, three AP math and science courses were

  17. 75 FR 53681 - Office of Elementary and Secondary Education Overview Information; Advanced Placement (AP) Test...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... include the College Board and IB Americas. VII. Agency Contact FOR FURTHER INFORMATION CONTACT: Francisco... placement tests and receive scores for which college academic credit is awarded. Program Authority: 20 U.S.C... through a proposed College Pathways and Accelerated Learning program. However, we are...

  18. Design and Manufacture of Elastically Tailored Tow Placed Plates

    NASA Technical Reports Server (NTRS)

    Tatting, Brain F.; Guerdal, Zafer; Jegley, Dawn (Technical Monitor)

    2002-01-01

    Elastic stiffness tailoring of laminated composite panels by allowing the fibers to curve within the plane of the laminate is a relatively novel design concept that has been demonstrated to be both beneficial and practical. In particular, for structures with highly non-uniform stress states, such as the case of a flat panel with a central hole subjected to in-plane loading, the concept is likely to provide substantial improvements in load carrying capability. The objective of the present study is to determine the effectiveness of stiffness tailoring through the use of curvilinear fibers to reduce stress concentrations around the hole and improve the load carrying capability of panels with holes. In this study software was created that translates standard finite element models with traditional laminate definitions into ones that possess stacking sequences with curvilinear fiber paths that are directly manufacturable using an advanced tow placement machine. Preliminary designs for the manufacturing and testing phase were determined through rudimentary design studies for flat plates without holes under axial compression. These candidate designs were then analyzed using finite element models that accurately reflect the test conditions and geometries in order to select final designs for testing. A total of six large panels, measuring three feet by six feet, each of which are used to produce four specimens with or without holes, were fabricated and delivered to NASA for machining and testing.

  19. Using Computer-Assisted Argumentation Mapping to develop effective argumentation skills in high school advanced placement physics

    NASA Astrophysics Data System (ADS)

    Heglund, Brian

    Educators recognize the importance of reasoning ability for development of critical thinking skills, conceptual change, metacognition, and participation in 21st century society. There is a recognized need for students to improve their skills of argumentation, however, argumentation is not explicitly taught outside logic and philosophy---subjects that are not part of the K-12 curriculum. One potential way of supporting the development of argumentation skills in the K-12 context is through incorporating Computer-Assisted Argument Mapping to evaluate arguments. This quasi-experimental study tested the effects of such argument mapping software and was informed by the following two research questions: 1. To what extent does the collaborative use of Computer-Assisted Argumentation Mapping to evaluate competing theories influence the critical thinking skill of argument evaluation, metacognitive awareness, and conceptual knowledge acquisition in high school Advanced Placement physics, compared to the more traditional method of text tables that does not employ Computer-Assisted Argumentation Mapping? 2. What are the student perceptions of the pros and cons of argument evaluation in the high school Advanced Placement physics environment? This study examined changes in critical thinking skills, including argumentation evaluation skills, as well as metacognitive awareness and conceptual knowledge, in two groups: a treatment group using Computer-Assisted Argumentation Mapping to evaluate physics arguments, and a comparison group using text tables to evaluate physics arguments. Quantitative and qualitative methods for collecting and analyzing data were used to answer the research questions. Quantitative data indicated no significant difference between the experimental groups, and qualitative data suggested students perceived pros and cons of argument evaluation in the high school Advanced Placement physics environment, such as self-reported sense of improvement in argument

  20. An Analysis of Advanced Placement (AP®) Examinations in Economics and Comparative Government and Politics. Research Report No. 2001-4. ETS RR-01-17

    ERIC Educational Resources Information Center

    Breland, Hunter M.; Oltman, Philip K.

    2001-01-01

    Advanced Placement Program® (AP®) Examinations in Macroeconomics, Microeconomics, and Comparative Government and Politics were studied to examine college course performance and gender differences. It was concluded that students who had received college credit for AP performed as well or better in higher-level college courses in Macroeconomics and…

  1. A Comparison of the Number of Hours of Sleep in High School Students Who Took Advanced Placement and/or College Courses and Those Who Did Not

    ERIC Educational Resources Information Center

    Jin, Qiushuang; Shi, Qian

    2008-01-01

    This study investigated the association between sleep deprivation and enrollment in Advanced Placement (AP) and/or college courses among high school students. Approximately 4,000 surveys were distributed, and 2,197 completed surveys were returned from students in Grades 9 to 12 at 15 high schools in Iowa. Findings indicated the majority of high…

  2. Advanced Placement® Exam-Taking and Performance: Relationships with First-Year Subject Area College Grades. Research Report No. 2011-4

    ERIC Educational Resources Information Center

    Patterson, Brian F.; Packman, Sheryl; Kobrin, Jennifer L.

    2011-01-01

    The purpose of this study was to examine the effects of Advanced Placement (AP) exam participation and performance on college grades for courses taken in the same subject area as students' AP Exam(s). Students' first-year college subject area grade point averages (SGPAs) were examined in nine subject areas: mathematics, computer science,…

  3. Advanced Placement[R] Exam-Taking and Performance: Relationships with First-Year Subject Area College Grades. Research Report 2011-4

    ERIC Educational Resources Information Center

    Patterson, Brian F.; Packman, Sheryl; Kobrin, Jennifer L.

    2011-01-01

    The purpose of this study was to examine the effects of Advanced Placement[R] (AP[R]) exam participation and performance on college grades for courses taken in the same subject area as students' AP Exam(s). Students' first-year college subject area grade point averages (SGPAs) were examined in nine subject areas: mathematics, computer science,…

  4. Students' Perceptions of the Social/Emotional Implications of Participation in Advanced Placement and International Baccalaureate Programs. Research Monograph Series. RM09238

    ERIC Educational Resources Information Center

    Foust, Regan Clark; Hertberg-Davis, Holly; Callahan, Carolyn M.

    2009-01-01

    Using qualitative methods, the researchers explored student perceptions of the social and emotional advantages and disadvantages of Advanced Placement (AP) and International Baccalaureate (IB) program participation, differences between the AP and IB programs in those perceptions, and whether or not students report experiencing a "forced-choice…

  5. 2013 Advanced Placement Exam Participation and Performance for Students in Montgomery County Public Schools and Public School Students in the State of Maryland and the Nation. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2013-01-01

    This memorandum provides data on the participation and performance of Advanced Placement (AP) exams taken by students in the Montgomery County (Maryland) Public Schools (MCPS) in the 2012-2013 school year as compared with those by public school students in Maryland and the nation. Generally, the number of AP exams taken by MCPS students in 2013…

  6. Filling a Plastic Bag with Carbon Dioxide: A Student-Designed Guided-Inquiry Lab for Advanced Placement and College Chemistry Courses

    ERIC Educational Resources Information Center

    Lanni, Laura M.

    2014-01-01

    A guided-inquiry lab, suitable for first-year general chemistry or high school advanced placement chemistry, is presented that uses only inexpensive, store-bought materials. The reaction of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar), under the constraint of the challenge to completely fill a sealable plastic bag with the…

  7. A Case for Adjusting Subjectively Rated Scores in the Advanced Placement Tests. Program Statistics Research. Technical Report No. 94-5.

    ERIC Educational Resources Information Center

    Longford, Nicholas T.

    A case is presented for adjusting the scores for free response items in the Advanced Placement (AP) tests. Using information about the rating process from the reliability studies, administrations of the AP test for three subject areas, psychology, computer science, and English language and composition, are analyzed. In the reliability studies, 299…

  8. An Exploration of Student and Teacher Social Presence in Asynchronous Discussion in an Online Advanced Placement Course for Rural High School Students

    ERIC Educational Resources Information Center

    de la Varre, Claire

    2012-01-01

    This study used a social presence construct derived from the Community of Inquiry (COI) framework, with cohesive, affective, and interactive components, to explore online discussion in an Advanced Placement course for rural high school students. The COI is based on the underlying theoretical framework of social constructivism, where interaction is…

  9. Incorporating a Comprehensive Drama Unit including a Theatre of the Absurd Component within the Advanced Placement English Program for Senior Level Students.

    ERIC Educational Resources Information Center

    Konaxis, Antoinette

    This practicum was designed to increase the experiences in the genre of world drama, to further develop student understanding of its evolution and impact on subsequently created drama, and to proffer a diverse collection of drama for senior level students pursuing the Advanced Placement (AP) English literature program. A comprehensive curriculum,…

  10. Assessing Competing Demands and Charting a Course: A Phenomenological Study of Advanced Placement U.S. History Teachers' Decision Making and Course Planning

    ERIC Educational Resources Information Center

    Poole, Kerry D.

    2014-01-01

    Florida has experienced some of the greatest growth of Advanced Placement (AP) programs in recent years and student scores on the AP exams have evolved into a highly significant metric in evaluating student proficiency and teacher and school effectiveness. Despite this growth, it is not well known how AP teachers make decisions about the content…

  11. Examining the Relationship of Content to Gender-Based Performance Differences in Advanced Placement Exams. Research Report No. 2002-12. ETS RR-02-25

    ERIC Educational Resources Information Center

    Buck, Gary; Kostin, Irene; Morgan, Rick

    2002-01-01

    The purpose of this study is to examine the content of the questions in a number of Advanced Placement Examinations and to attempt to identify content that is related to gender-based performance differences. Free-response questions for ten forms of the AP® Exams in U.S. History, European History, Biology, Microeconomics, and Macroeconomics were…

  12. A Forum To Expand Advanced Placement Opportunities: Increasing Access and Improving Preparation in High Schools. Transcript of Proceedings (Washington, D.C., February 11, 2000).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This transcript reproduces a Department of Education/College Board-sponsored discussion on ways to expand advanced-placement (AP) opportunities in high schools. The deliberations opened with a presentation by Terry Peterson, Senior Advisor to Education Secretary Richard Riley, in which he focused on the importance of AP courses for minority and…

  13. Academic Preparedness and College Preparation Efforts: A Comparative Analysis of Perception of High School Advanced Placement Teachers and College Admissions Personnel

    ERIC Educational Resources Information Center

    Driver, Jason Hughes

    2014-01-01

    This study examines the relationship between high school efforts at post-secondary preparation for college bound students and the expectations of college and university admissions personnel. The Advanced Placement (AP) teachers and administrators at a rural Northwest Florida high school were administered a quantitative survey in order to collect…

  14. 2014 Advanced Placement Exam Participation and Performance for Students in Montgomery County Public Schools and Public School Students in the State of Maryland and the Nation. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2014-01-01

    The continuing emphasis by Montgomery County (Maryland) Public Schools (MCPS) on rigorous course taking resulted in MCPS students taking a record-setting 33,662 Advanced Placement (AP) exams in 2014. Additionally, the percentage of AP exams taken by MCPS students who attained scores of 3 or higher (73.9 percent) was 13.0 and 16.7 percentage points…

  15. Performance and Advanced Data Placement Techniques with Ceph's Distributed Storage System

    NASA Astrophysics Data System (ADS)

    Poat, M. D.; Lauret, J.

    2016-10-01

    The STAR online computing environment is a demanding concentrated multipurpose compute system with the objective to obtain maximum throughput with process concurrency. Motivation for extending the STAR online compute farm from a simple job processing tool for data taking, into a multipurpose resource equipped with a large storage system would lead any dedicated resources to become an extremely efficient and an attractive multi-purpose facility. To achieve this goal, our compute farm is using the Ceph distributed storage system which has proven to be an agile solution due to its effective POSIX interface and excelling its object storage with IO concurrency. With this we have taken our cluster one step further in terms of IO performance by investigating and leveraging new technologies and key features of Ceph. With the acquisition of a 10Gb backbone network we have ensured to eliminate the network as a limitation. With further acquisition of large fast drives (1TB SSDs) we will show how one can customize the data placement options Ceph has to offer such as primary affinity, mounting OSD journals on SSDs, and Cache Tiering along with non-Ceph related local disk caching techniques. We will discuss the latest performance results along with the expected results by using each technique. We hope this paper will serve the community's interest for the Ceph distributed storage solution.

  16. Advanced L2 Learners and Reading Placement: Self-Assessment, CBT, and Subsequent Performance

    ERIC Educational Resources Information Center

    Brantmeier, Cindy

    2006-01-01

    There is a dearth of research involving advanced second language (L2) learners in the USA [Brantmeier, C., 2001. Second language reading research on passage content and gender: challenges for the intermediate level curriculum, Foreign Language Annals 34, 325-333; Young, D.J., 2003. Workshop on overcoming anxiety in the foreign language classroom.…

  17. Dynamic Tow Maneuver Orbital Launch Technique

    NASA Technical Reports Server (NTRS)

    Rutan, Elbert L. (Inventor)

    2014-01-01

    An orbital launch system and its method of operation use a maneuver to improve the launch condition of a booster rocket and payload. A towed launch aircraft, to which the booster rocket is mounted, is towed to a predetermined elevation and airspeed. The towed launch aircraft begins the maneuver by increasing its lift, thereby increasing the flight path angle, which increases the tension on the towline connecting the towed launch aircraft to a towing aircraft. The increased tension accelerates the towed launch aircraft and booster rocket, while decreasing the speed (and thus the kinetic energy) of the towing aircraft, while increasing kinetic energy of the towed launch aircraft and booster rocket by transferring energy from the towing aircraft. The potential energy of the towed launch aircraft and booster rocket is also increased, due to the increased lift. The booster rocket is released and ignited, completing the launch.

  18. TIMSS Advanced 2015 and Advanced Placement Calculus & Physics. A Framework Analysis. Research in Review 2016-1

    ERIC Educational Resources Information Center

    Lazzaro, Christopher; Jones, Lee; Webb, David C.; Grover, Ryan; Di Giacomo, F. Tony; Marino, Katherine Adele

    2016-01-01

    This report will determine to what degree the AP Physics 1 and 2 and AP Calculus AB and BC frameworks are aligned with the Trends in International Mathematics and Science Study (TIMSS) Advanced Physics and Mathematics frameworks. This will enable an exploration of any differences in content coverage and levels of complexity, and will set the stage…

  19. A comparative analysis of teacher-authored websites in high school honors and Advanced Placement physics for Web-design and NSES content and process standards

    NASA Astrophysics Data System (ADS)

    Persin, Ronald C.

    The purpose of this study was to investigate whether statistically significant differences existed between high school Honors Physics websites and those of Advanced Placement (AP) Physics in terms of Web-design, National Science Education Standards (NSES) Physics content, and NSES Science Process standards. The procedure began with the selection of 152 sites comprising two groups with equal sample sizes of 76 for Honors Physics and for Advanced Placement Physics. The websites used in the study were accumulated using the Google(TM) search engine. To find Honors Physics websites, the search words "honors physics high school" were entered as the query into the search engine. To find sites for Advanced Placement Physics, the query, "advanced placement physics high school," was entered into the search engine. The evaluation of each website was performed using an instrument developed by the researcher based on three attributes: Web-design, NSES Physics content, and NSES Science Process standards. A "1" was scored if the website was found to have each attribute, otherwise a "0" was given. This process continued until all 76 websites were evaluated for each of the two types of physics websites, Honors and Advanced Placement. Subsequently the data were processed using Excel functions and the SPSS statistical software program. The mean and standard deviation were computed individually for the three attributes under consideration. Three, 2-tailed, independent samples t tests were performed to compare the two groups of physics websites separately on the basis of Web Design, Physics Content, and Science Process. The results of the study indicated that there was only one statistically significant difference between high school Honors Physics websites and those of AP Physics. The only difference detected was in terms of National Science Education Standards Physics content. It was found that Advanced Placement Physics websites contained more NSES physics content than Honors

  20. Keyword: Placement

    ERIC Educational Resources Information Center

    Cassuto, Leonard

    2012-01-01

    The practical goal of graduate education is placement of graduates. But what does "placement" mean? Academics use the word without thinking much about it. "Placement" is a great keyword for the graduate-school enterprise. For one thing, its meaning certainly gives a purpose to graduate education. Furthermore, the word is a portal into the way of…

  1. The Effect of Enrollment in Middle School Challenge Courses on Advanced Placement Exams in Social Studies and Science

    NASA Astrophysics Data System (ADS)

    Glaude-Bolte, Katherine

    Educators seek to guide students through appropriate programs and courses that prepare them for future success, in more advanced coursework and in other challenges of life. Some middle schools offer Challenge, or honors, courses for students who have demonstrated high ability. High schools often offer Advanced Placement (AP) courses, which are taught at the college level. This study examined the correlation between enrollment in middle school Challenge courses and subsequent AP exam category scores in social studies and science in a suburban school district. The independent variables were the number of years of enrollment in middle school social studies or science Challenge courses. The dependent variables were the AP exam category scores in the eight social studies AP courses or the six science AP courses. The sample sizes were limited to the number of students who took an AP social studies or science exam and also attended the middle school of study. The null hypothesis was that there was no relationship between the two variables. This study included eight social studies AP courses and six science AP courses. A significant positive correlation was indicated in only two of the courses, U.S. Government and Comparative Government, supporting the claim that enrollment in middle school Challenge social studies was correlated with success, at least on these two AP exams. In the remaining 12 courses, there was not enough evidence to reject the null hypothesis. Therefore, enrollment in middle school Challenge science and social studies courses generally did not seem to correlate with AP exam category scores. Results of this study call into question the validity of the claim by the district that enrollment in Challenge courses helps prepare students for rigorous coursework in high school. Several factors, including student readiness, teacher training, familiarity with course content, and previous AP experience may contribute more to a student's AP exam category score

  2. 78 FR 49543 - Towing Safety Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... SECURITY Coast Guard Towing Safety Advisory Committee AGENCY: Coast Guard, DHS. ACTION: Committee Management; Notice of Federal Advisory Committee Meeting. SUMMARY: The Towing Safety Advisory Committee (TSAC... related to shallow draft inland, coastal waterway navigation and towing safety. The meetings will be...

  3. African American Advanced Placement chemistry students and their developing study habits: A phenomenologically-based interpretive study

    NASA Astrophysics Data System (ADS)

    Rasmussen, Natalie D.

    The academic achievement gap between African American and White students has gained much attention in recent years. Much has been written about the causes of and reasons for this problem ranging from the vestigial effects of slavery to poor parenting. Much less has been written or understood about its solution. While it is impossible for educators to change the pasts of their African American students, it is possible to effect change for the few minutes in which they are in direct contact with them each day. If African American science students are taught effective study skills and habits, then perhaps they might have the tools to close the achievement gap themselves. The participants in this phenomenologically based interpretive study were five African American Advanced Placement Chemistry students from an inner-city high school. Three in-depth interviews were conducted with each of the participants during the beginning, middle and end of a semester. The purpose of the interviews was to locate the students in terms of their thought processes, experiences and perceived barriers concerning the nature and practice of effective study and retention of chemistry content. The interviews were recorded and transcribed. The texts were then analyzed for common themes. Five common themes emerged from the interviews. These were: (1) Homework vs. Study: a distinction between homework---which students knew how to approach; and study---which they did not. (2) Student Effort: their changing perception of adequate and effective study practices while in a rigorous course. (3) Teacher Rigor: they perceived high expectations and challenging work as a sign of respect from their teachers. (4) Parental Involvement: students' admission that they desired more input from parents regarding their academic performance. (5) Racial Considerations: their need to disprove negative stereotypes and their personal observations regarding racial differences in studying. A discussion of the themes and

  4. Characterization and development of materials for advanced textile composites

    NASA Technical Reports Server (NTRS)

    Hartness, J. Timothy; Greene, Timothy L.; Taske, Leo E.

    1993-01-01

    Work ongoing under the NASA Langley - Advanced Composite Technology (ACT) program is discussed. The primary emphasis of the work centers around the development and characterization of graphite fiber that has been impregnated with an epoxy powder. Four epoxies have been characterized in towpreg form as to their weaveability and braidability. Initial mechanical properties have been generated on each resin system. These include unidirectional as well as 8-harness satin cloth. Initial 2D and 3D weaving and braiding trials will be reported on as well as initial efforts to develop towpreg suitable for advanced tow placement.

  5. Tape Placement Head for Applying Thermoplastic Tape to an Object

    NASA Technical Reports Server (NTRS)

    Cope, Ralph D. (Inventor); Funck, Steve B. (Inventor); Gruber, Mark B. (Inventor); Lamontia, Mark A. (Inventor); Johnson, Anthony D. (Inventor)

    2008-01-01

    A tape placement head for applying thermoplastic tape to an object includes a heated feeder which guides the tape/tow to a heated zone. The heated zone has a line compactor having a single row of at least one movable heated member. An area compactor is located in the heated zone downstream from the line compactor. The area compactor includes a plurality of rows of movable feet which are extendable toward the tape/tow different distances with respect to each other to conform to the shape of the object. A shim is located between the heated compactors and the tape/tow. A chilled compactor is in a chilled zone downstream from the heated zone. The chilled zone includes a line chilled compactor and an area chilled compactor. A chilled shim is mounted between the chilled compactor and the tape/tow.

  6. Aircraft towing feasibility study. Final report

    SciTech Connect

    Not Available

    1980-09-01

    Energy costs and availability are major concerns in most parts of the world. Many ways of increasing energy supply and reducing consumption are being proposed and investigated. One that holds considerable promise is the extended towing of aircraft between airport runways and terminal gate areas with engines shut down. This study provides a preliminary assessment of the constraints on and feasibility of extended aircraft towing. Past aircraft towing experience and the state-of-the-art in towing equipment are reviewed. Safety and operational concerns associated with aircraft towing are identified, and the benefits and costs of implementing aircraft towing at 20 major US airports are analyzed. It was concluded that extended aircraft towing is technically feasible and that substantial reductions in aircraft fuel consumption and air pollutant emissions can be achieved through its implementation. It was also concluded that, although capital and operating costs associated with towing would be increased, net savings could generally be attained at these airports. Because of the lack of past experience and the necessity of proving the cost effectiveness of the towing concept, a demonstration of the feasibility of large-scale aircraft towing is necessary. The study evaluates the suitability of the 20 study airports as potential demonstration sites and makes recommendations for the first demonstration project.

  7. Continuous, linearly intermixed fiber tows and composite molded article thereform

    NASA Technical Reports Server (NTRS)

    McMahon, Paul E. (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

    2000-01-01

    The instant invention involves a process used in preparing fibrous tows which may be formed into polymeric plastic composites. The process involves the steps of (a) forming a carbon fiber tow; (b) forming a thermoplastic polymeric fiber tow; (c) intermixing the two tows; and (d) withdrawing the intermixed tow for further use.

  8. An analysis of predictors of enrollment and successful achievement for girls in high school Advanced Placement physics

    NASA Astrophysics Data System (ADS)

    Depalma, Darlene M.

    A problem within science education in the United States persists. U.S students rank lower in science than most other students from participating countries on international tests of achievement (National Center for Education Statistics, 2003). In addition, U.S. students overall enrollment rate in high school Advanced Placement (AP) physics is still low compared to other academic domains, especially for females. This problem is the background for the purpose of this study. This investigation examined cognitive and motivational variables thought to play a part in the under-representation of females in AP physics. Cognitive variables consisted of mathematics, reading, and science knowledge, as measured by scores on the 10th and 11th grade Florida Comprehensive Assessment Tests (FCAT). The motivational factors of attitude, stereotypical views toward science, self-efficacy, and epistemological beliefs were measured by a questionnaire developed with questions taken from previously proven reliable and valid instruments. A general survey regarding participation in extracurricular activities was also included. The sample included 12th grade students from two high schools located in Seminole County, Florida. Of the 106 participants, 20 girls and 27 boys were enrolled in AP physics, and 39 girls and 20 boys were enrolled in other elective science courses. Differences between males and females enrolled in AP physics were examined, as well as differences between females enrolled in AP physics and females that chose not to participate in AP physics, in order to determine predictors that apply exclusively to female enrollment in high school AP physics and predictors of an anticipated science related college major. Data were first analyzed by Exploratory Factor Analysis, followed by Analysis of Variance (ANOVA), independent t-tests, univariate analysis, and logistic regression analysis. One overall theme that emerged from this research was findings that refute the ideas that

  9. Towed Twin-Fuselage Glider Launch System (CGI Animation)

    NASA Video Gallery

    The towed glider is an element of the novel rocket-launching concept of the Towed Glider Air-Launch System (TGALS). The TGALS demonstration’s goal is to provide proof-of-concept of a towed, airborn...

  10. Process for preparing tows from composite fiber blends

    NASA Technical Reports Server (NTRS)

    McMahon, Paul (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

    1989-01-01

    A continuous, substantially uniform tow useful in forming composite molded articles is prepared by forming a continuous tow of continuous carbon fibers, forming a continuous tow of thermoplastic polymer fibers to a selected width, uniformly and continuously spreading the carbon fiber two to a width that is essentially the same as the selected width for the thermoplastic polymer fiber tow, intermixing the tows intimately, uniformly and continuously, in a relatively tension-free state, and continuosuly withdrawing the intermixed tow.

  11. Towed Subsurface Optical Communications Buoy

    NASA Technical Reports Server (NTRS)

    Stirbl, Robert C.; Farr, William H.

    2013-01-01

    The innovation allows critical, high-bandwidth submarine communications at speed and depth. This reported innovation is a subsurface optical communications buoy, with active neutral buoyancy and streamlined flow surface veins for depth control. This novel subsurface positioning for the towed communications buoy enables substantial reduction in water-absorption and increased optical transmission by eliminating the intervening water absorption and dispersion, as well as by reducing or eliminating the beam spread and the pulse spreading that is associated with submarine-launched optical beams.

  12. Eclipse - tow flight closeup and release

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This clip, running 15 seconds in length, shows the QF-106 'Delta Dart' gear down, with the tow rope secured to the attachment point above the aircraft nose. First there is a view looking back from the C-141A, then looking forward from the nose of the QF-106, and finally a shot of the aircraft being released from the tow rope. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate a reusable tow launch vehicle concept developed by KST. Kelly Space and Technology hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed

  13. Response of automated tow placed laminates to stress concentrations

    NASA Technical Reports Server (NTRS)

    Cairns, Douglas S.; Ilcewicz, Larry B.; Walker, Tom

    1993-01-01

    In this study, the response of laminates with stress concentrations is explored. Automated Tow Placed (ATP, also known as Fiber Placement) laminates are compared to conventional tape layup manufacturing. Previous tensile fracture tests on fiber placed laminates show an improvement in tensile fracture of large notches over 20 percent compared to tape layup laminates. A hierarchial modeling scheme is presented. In this scheme, a global model is developed for laminates with notches. A local model is developed to study the influence of inhomogeneities at the notch tip, which are a consequence of the fiber placement manufacturing technique. In addition, a stacked membrane model was developed to study delaminations and splitting on a ply-by-ply basis. The results indicate that some benefit with respect to tensile fracture (up to 11 percent) can be gained from inhomogeneity alone, but that the most improvement may be obtained with splitting and delaminations which are more severe in the case of fiber placement compared to tape layup. Improvements up to 36 percent were found from the model for fiber placed laminates with damage at the notch tip compared to conventional tape layup.

  14. Nutritional status and feeding-tube placement in patients with locally advanced hypopharyngeal cancer included in an induction chemotherapy-based larynx preservation program.

    PubMed

    Bozec, Alexandre; Benezery, Karen; Chamorey, Emmanuel; Ettaiche, Marc; Vandersteen, Clair; Dassonville, Olivier; Poissonnet, Gilles; Riss, Jean-Christophe; Hannoun-Lévi, Jean-Michel; Chand, Marie-Eve; Leysalle, Axel; Saada, Esma; Sudaka, Anne; Haudebourg, Juliette; Hebert, Christophe; Falewee, Marie-Noelle; Demard, François; Santini, José; Peyrade, Frédéric

    2016-09-01

    The objective of the study is to evaluate the nutritional status and determine its impact on clinical outcomes in patients with locally advanced hypopharyngeal cancer included in an induction chemotherapy (ICT)-based larynx preservation program without prophylactic feeding-tube placement. All patients with locally advanced (T3/4, N0-3, M0) hypopharyngeal squamous cell carcinoma, technically suitable for total pharyngolaryngectomy, treated by docetaxel, cisplatin and 5-fluorouracil (TPF)-ICT for larynx preservation at our institution between 2004 and 2013, were included in this retrospective study. Patients' nutritional status was closely monitored. Enteral nutrition was used if and when a patient was unable to sustain per-oral nutrition and hydration. The impact of nutritional status on clinical outcomes was investigated in univariate and multivariate analysis. A total of 53 patients (42 men and 11 women, mean age = 58.6 ± 8.2 years) were included in this study. Six (11.3 %) patients had lost more than 10 % of their usual body weight before therapy. Compared with patients' usual weight, the mean maximum patient weight loss during therapeutic management was 8.7 ± 4.5 kg. Enteral nutrition was required in 17 patients (32 %). We found no influence of the tested nutritional status-related factors on response to ICT, toxicity of ICT, overall, cause-specific and recurrence-free survival, and on post-therapeutic swallowing outcome. Maximum weight loss was significantly associated with a higher risk of enteral tube feeding during therapy (p = 0.03) and of complications (grade ≥3, p = 0.006) during RT. Without prophylactic feeding-tube placement, approximately one-third of the patients required enteral nutrition. There was no significant impact of nutritional status on oncologic or functional outcomes.

  15. Controlling iceberg roll/stability during towing around drillships

    SciTech Connect

    Benedict, C.P.; Lewis, J.C.; Dinn, G.J.; Learning, F.R.

    1981-01-01

    Field iceberg survey data were collected and on the basis of Lagrangian computer analysis, a large sample of simulated bergs were towed from random stable floating positions. This paper presents: the results on instrumenting iceberg tow forces on the Aquitaine site during the 1980 drilling program, and an operational procedure for predicting critical tow forces on the basis of pre-tow surveys.

  16. A Forum To Expand Advanced Placement Opportunities: Increasing Access and Improving Preparation in High Schools. Strategies To Overcome Challenges in Rural and Small Schools. Transcript of Proceedings (Washington, D.C., February 11, 2000).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This transcript reproduces a Department of Education/College Board sponsored discussion on ways to expand advanced placement (AP) opportunities in high schools. The deliberations opened with a presentation by Phil Chavez, an assistant principal in San Antonio, Texas, who outlined the genesis and development of the AP program in his predominantly…

  17. Monitoring Faculty Consultant Performance in the Advanced Placement English Literature and Composition Program with a Many-Faceted Rasch Model. Research Report No. 2003-1. ETS RR-03-01

    ERIC Educational Resources Information Center

    Engelhard, George, Jr.; Myford, Carol M.

    2003-01-01

    The purpose of this study was to examine, describe, evaluate, and compare the rating behavior of faculty consultants who scored essays written for the Advanced Placement English Literature and Composition (AP® ELC) Exam. Data from the 1999 AP ELC Exam were analyzed using FACETS (Linacre, 1998) and SAS. The faculty consultants were not all…

  18. System Applies Polymer Powder To Filament Tow

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.; Snoha, John J.; Marchello, Joseph M.

    1993-01-01

    Polymer powder applied uniformly and in continuous manner. Powder-coating system applies dry polymer powder to continuous fiber tow. Unique filament-spreading technique, combined with precise control of tension on fibers in system, ensures uniform application of polymer powder to web of spread filaments. Fiber tows impregnated with dry polymer powders ("towpregs") produced for preform-weaving and composite-material-molding applications. System and process valuable to prepreg industry, for production of flexible filament-windable tows and high-temperature polymer prepregs.

  19. Preservice Teachers' Experiences with Advanced Digital Technologies: The Interplay between Technology in a Preservice Classroom and in Field Placements

    ERIC Educational Resources Information Center

    Meagher, Michael; Ozgun-Koca, Asli; Edwards, Michael Todd

    2011-01-01

    This paper reports on a study of 22 preservice teachers enrolled in a first-semester mathematics teaching methods course. Course activities included participation in two separate field experiences in neighboring school districts. The methods class placed considerable emphasis on the use of advanced digital technologies in the teaching and learning…

  20. Feeding Tube Placement in Patients with Advanced Dementia: The Beliefs and Practice Patterns of Speech-Language Pathologists

    ERIC Educational Resources Information Center

    Sharp, Helen M.; Shega, Joseph W.

    2009-01-01

    Purpose: To describe the beliefs and practices of speech-language pathologists (SLPs) about the use of percutaneous endoscopic gastrostomy (PEG) among patients with advanced dementia and dysphagia. Method: A survey was mailed to a geographically stratified random sample of 1,050 medical SLPs. Results: The response rate was 57%, and 326 surveys met…

  1. 14 CFR 25.509 - Towing loads.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... towing fittings and must act parallel to the ground. In addition— (1) A vertical load factor equal to 1.0...) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of...

  2. 14 CFR 25.509 - Towing loads.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... towing fittings and must act parallel to the ground. In addition— (1) A vertical load factor equal to 1.0...) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of...

  3. 14 CFR 25.509 - Towing loads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... towing fittings and must act parallel to the ground. In addition— (1) A vertical load factor equal to 1.0...) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of...

  4. 14 CFR 25.509 - Towing loads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... towing fittings and must act parallel to the ground. In addition— (1) A vertical load factor equal to 1.0...) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of...

  5. 14 CFR 25.509 - Towing loads.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... towing fittings and must act parallel to the ground. In addition— (1) A vertical load factor equal to 1.0...) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of...

  6. Communication: Cargo towing by artificial swimmers

    NASA Astrophysics Data System (ADS)

    Debnath, Debajyoti; Ghosh, Pulak K.; Li, Yunyun; Marchesoni, Fabio; Li, Baowen

    2016-11-01

    An active swimmer can tow a passive cargo by binding it to form a self-propelling dimer. The orientation of the cargo relative to the axis of the active dimer's head is determined by the hydrodynamic interactions associated with the propulsion mechanism of the latter. We show how the tower-cargo angular configuration greatly influences the dimer's diffusivity and, therefore, the efficiency of the active swimmer as a micro-towing motor.

  7. Computational Analysis of Towed Ballute Interactions

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.; Anderson, Brian P.

    2002-01-01

    A ballute (balloon-parachute) is an inflatable, aerodynamic drag device for application to planetary entry vehicles. Ballutes may be directly attached to a vehicle, increasing its cross-sectional area upon inflation, or towed behind the vehicle as a semi-independent device that can be quickly cut free when the requisite change in velocity is achieved. The aerothermodynamics of spherical and toroidal towed ballutes are considered in the present study. A limiting case of zero towline length (clamped system) is also considered. A toroidal system can be designed (ignoring influence of the tethers) such that all flow processed by the bow shock of the towing spacecraft passes through the hole in the toroid. For a spherical ballute, towline length is a critical parameter that affects aeroheating on the ballute being towed through the spacecraft wake. In both cases, complex and often unsteady interactions ensue in which the spacecraft and its wake resemble an aero spike situated in front of the ballute. The strength of the interactions depends upon system geometry and Reynolds number. We show how interactions may envelope the base of the towing spacecraft or impinge on the ballute surface with adverse consequences to its thermal protection system. Geometric constraints to minimize or eliminate such adverse interactions are discussed. The towed, toroidal system and the clamped, spherical system show greatest potential for a baseline design approach.

  8. A comparison of the number of hours of sleep in high school students who took advanced placement and/or college courses and those who did not.

    PubMed

    Jin, Qiushuang; Shi, Qian

    2008-12-01

    This study investigated the association between sleep deprivation and enrollment in Advanced Placement (AP) and/or college courses among high school students. Approximately 4,000 surveys were distributed, and 2,197 completed surveys were returned from students in Grades 9 to 12 at 15 high schools in Iowa. Findings indicated the majority of high school students were sleep deprived. Sleep deprivation was significantly associated with enrollment in AP/college courses. Results indicated that enrollment in AP/college courses had a greater impact on younger students than older students. Compared with non-AP/college course takers, AP/college course takers slept approximately 20 minutes less per night. Specifically, 9th- and 10th-grade AP/college course takers slept approximately 1 hour less and 40 minutes less, respectively. In addition, students enrolled in two or more AP/college classes received 1 hour less and 30 minutes less among 10th and 11th graders, respectively. These results provide useful information on adolescent sleep patterns for school nurses.

  9. The effects of a test-taking strategy intervention for high school students with test anxiety in advanced placement science courses

    NASA Astrophysics Data System (ADS)

    Markus, Doron J.

    Test anxiety is one of the most debilitating and disruptive factors associated with underachievement and failure in schools (Birenbaum, Menucha, Nasser, & Fadia, 1994; Tobias, 1985). Researchers have suggested that interventions that combine multiple test-anxiety reduction techniques are most effective at reducing test anxiety levels (Ergene, 2003). For the current study, involving 62 public high school students enrolled in advanced placement science courses, the researcher designed a multimodal intervention designed to reduce test anxiety. Analyses were conducted to assess the relationships among test anxiety levels, unit examination scores, and irregular multiple-choice error patterns (error clumping), as well as changes in these measures after the intervention. Results indicate significant, positive relationships between some measures of test anxiety and error clumping, as well as significant, negative relationships between test anxiety levels and student achievement. In addition, results show significant decreases in holistic measures of test anxiety among students with low anxiety levels, as well as decreases in Emotionality subscores of test anxiety among students with high levels of test anxiety. There were no significant changes over time in the Worry subscores of test anxiety. Suggestions for further research include further confirmation of the existence of error clumping, and its causal relationship with test anxiety.

  10. Aerothermodynamic Analyses of Towed Ballutes

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.; Buck, Greg; Moss, James N.; Nielsen, Eric; Berger, Karen; Jones, William T.; Rudavsky, Rena

    2006-01-01

    A ballute (balloon-parachute) is an inflatable, aerodynamic drag device for application to planetary entry vehicles. Two challenging aspects of aerothermal simulation of towed ballutes are considered. The first challenge, simulation of a complete system including inflatable tethers and a trailing toroidal ballute, is addressed using the unstructured-grid, Navier-Stokes solver FUN3D. Auxiliary simulations of a semi-infinite cylinder using the rarefied flow, Direct Simulation Monte Carlo solver, DSV2, provide additional insight into limiting behavior of the aerothermal environment around tethers directly exposed to the free stream. Simulations reveal pressures higher than stagnation and corresponding large heating rates on the tether as it emerges from the spacecraft base flow and passes through the spacecraft bow shock. The footprint of the tether shock on the toroidal ballute is also subject to heating amplification. Design options to accommodate or reduce these environments are discussed. The second challenge addresses time-accurate simulation to detect the onset of unsteady flow interactions as a function of geometry and Reynolds number. Video of unsteady interactions measured in the Langley Aerothermodynamic Laboratory 20-Inch Mach 6 Air Tunnel and CFD simulations using the structured grid, Navier-Stokes solver LAURA are compared for flow over a rigid spacecraft-sting-toroid system. The experimental data provides qualitative information on the amplitude and onset of unsteady motion which is captured in the numerical simulations. The presence of severe unsteady fluid - structure interactions is undesirable and numerical simulation must be able to predict the onset of such motion.

  11. Advanced fiber/matrix material systems

    NASA Technical Reports Server (NTRS)

    Hartness, J. Timothy

    1991-01-01

    Work completed in Phase 1 of the NASA Advanced Composite Technology program is discussed. Two towpreg forms (commingled yarns and fused powder towpregs) are being characterized under the program. These towpregs will be used to evaluate textile fabrication technologies for advanced aircraft composite structures. The unique characteristic of both of these material forms is that both fiber and matrix resin are handled in a single operation such as weaving, braiding, or fiber placement. The evaluation of both commingled and fused powder towpreg is described. Various polymer materials are considered for both subsonic and supersonic applications. Polymers initially being evaluated include thermoplastic polyimides such as Larc-TPI and New-TPI, thermoplastics such as PEEK and PEKEKK as well as some toughened crosslinked polyimides. Preliminary mechanical properties as well as tow handling are evaluated.

  12. 10. VIEW NORTH FROM FLOOR LEVEL OF DRYDOCK OF TOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW NORTH FROM FLOOR LEVEL OF DRY-DOCK OF TOW TANK No. 1, WITH TORPEDO BODY BEING PREPARED FOR TANK TESTING. - NASA Langley Research Center, Seaplane Towing Channel, 108 Andrews Street, Hampton, Hampton, VA

  13. 77 FR 49002 - Towing Safety Advisory Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-15

    ... revision of NVIC 1-95, Voluntary Training Standards for Entry-Level Personnel on Towing Industry Vessels... revision of NVIC 1-95, Voluntary Training Standards for Entry-Level Personnel on Towing Industry...

  14. Efficiency of cargo towing by a microswimmer.

    PubMed

    Raz, O; Leshansky, A M

    2008-05-01

    We study the properties of an arbitrary microswimmer towing a passive load through a viscous liquid. The simple close-form expression for the dragging efficiency of a microswimmer dragging a distant load is found, and the approximation for finite mutual proximity is derived. We show that, while the swimmer can be arbitrarily efficient, the dragging efficiency is always bounded from above. It is also demonstrated, that opposite to Purcell's assumption [E. M. Purcell, Proc. Natl. Acad. Sci. U.S.A. 94, 11307 (1997)], the hydrodynamic coupling can "help" the propeller to tow the load. We support our conclusions by rigorous numerical calculations for the rotary swimmer, towing a spherical cargo positioned at a finite distance.

  15. Efficiency of cargo towing by a microswimmer

    NASA Astrophysics Data System (ADS)

    Raz, O.; Leshansky, A. M.

    2008-05-01

    We study the properties of an arbitrary microswimmer towing a passive load through a viscous liquid. The simple close-form expression for the dragging efficiency of a microswimmer dragging a distant load is found, and the approximation for finite mutual proximity is derived. We show that, while the swimmer can be arbitrarily efficient, the dragging efficiency is always bounded from above. It is also demonstrated, that opposite to Purcell’s assumption [E. M. Purcell, Proc. Natl. Acad. Sci. U.S.A. 94, 11307 (1997)], the hydrodynamic coupling can “help” the propeller to tow the load. We support our conclusions by rigorous numerical calculations for the rotary swimmer, towing a spherical cargo positioned at a finite distance.

  16. 77 FR 31631 - Towing Safety Advisory Committee; Vacancies

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-29

    ... SECURITY Coast Guard Towing Safety Advisory Committee; Vacancies AGENCY: Coast Guard, DHS. ACTION: Request for applications. SUMMARY: The Coast Guard seeks applications for membership on the Towing Safety... shallow-draft inland and coastal waterway navigation and towing safety. DATES: Applicants should submit...

  17. 49 CFR 392.63 - Towing or pushing loaded buses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with passengers aboard shall be towed or pushed; nor shall any person use or permit to be used a bus...

  18. 49 CFR 392.63 - Towing or pushing loaded buses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with passengers aboard shall be towed or pushed; nor shall any person use or permit to be used a bus...

  19. 49 CFR 392.63 - Towing or pushing loaded buses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with passengers aboard shall be towed or pushed; nor shall any person use or permit to be used a bus...

  20. 49 CFR 392.63 - Towing or pushing loaded buses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with passengers aboard shall be towed or pushed; nor shall any person use or permit to be used a bus...

  1. 49 CFR 392.63 - Towing or pushing loaded buses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with passengers aboard shall be towed or pushed; nor shall any person use or permit to be used a bus...

  2. Viability of 3 D Woven Carbon Cloth and Advanced Carbon-Carbon Ribs for Adaptive Deployable Entry Placement Technology (ADEPT) for Future NASA Missions

    NASA Technical Reports Server (NTRS)

    Venkatapathy, Ethiraj; Arnold, James O.; Peterson, K. H.; Blosser, M. L.

    2013-01-01

    This paper describes aerothermodynamic and thermal structural testing that demonstrate the viability of three dimensional woven carbon cloth and advanced carbon-carbon (ACC) ribs for use in the Adaptive Deployable Entry Placement Technology (ADEPT). ADEPT is an umbrella-like entry system that is folded for stowage in the launch vehicle's shroud and deployed prior to reaching the atmeopheric interface. A key feature of the ADEPT concept is a lower ballistic coefficient for delivery of a given payload than seen with conventional, rigid body entry systems. The benefits that accrue from the lower ballistic coefficient incllude factor-of-ten reductions of deceleration forces and entry heating. The former enables consideration of new classes of scientific instruments for solar system exploration while the latter enables the design of a more efficient thermal protection system. The carbon cloth base lined for ADEPT has a dual use in that it serves as the thermal protection system and as the "skin" that transfers aerdynamic deceleration loads to its umbrella-like substructure. Arcjet testing described in this paper was conducted for some of the higher heating conditions for a future Venus mission using the ADEPT concept, thereby showing that the carbon cloth can perform in a relevant entry environment. Recently completed the thermal structural testing of the cloth attached to a representative ACC rib design is also described. Finally, this paper describes a preliminary engineering level code, based on the arcjet data, that can be used to estimate cloth thickness for future ADEPT missions and to predict carbon cloth performance in future arcjet tests.

  3. X-34 and HSTV tow vehicle on lakebed prior to tow test

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Following initial captive flight tests last year at NASA's Dryden Flight Research Center, Edwards Air Force Base, California, the X-34 technology demonstrator began a new series of tests last week in which it is being towed behind a semi-truck and released to coast on the Edwards dry lakebed. On July 20, 2000, it was towed and released twice at speeds of five and 10 miles per hour. On July 24, 2000, it was towed and released twice at 10 and 30 miles per hour. Twelve tests are planned during which the X-34 will be towed for distances up to 10,000 feet and released at speeds up to 80 miles per hour. The test series is expected to last at least six weeks.

  4. SEADYN Analysis of a Tow Line for a High Altitude Towed Glider

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.

    1996-01-01

    The concept of using a system, consisting of a tow aircraft, glider and tow line, which would enable subsonic flight at altitudes above 24 km (78 kft) has previously been investigated. The preliminary results from these studies seem encouraging. Under certain conditions these studies indicate the concept is feasible. However, the previous studies did not accurately take into account the forces acting on the tow line. Therefore in order to investigate the concept further a more detailed analysis was needed. The code that was selected was the SEADYN cable dynamics computer program which was developed at the Naval Facilities Engineering Service Center. The program is a finite element based structural analysis code that was developed over a period of 10 years. The results have been validated by the Navy in both laboratory and at actual sea conditions. This code was used to simulate arbitrarily-configured cable structures subjected to excitations encountered in real-world operations. The Navy's interest was mainly for modeling underwater tow lines, however the code is also usable for tow lines in air when the change in fluid properties is taken into account. For underwater applications the fluid properties are basically constant over the length of the tow line. For the tow aircraft/glider application the change in fluid properties is considerable along the length of the tow line. Therefore the code had to be modified in order to take into account the variation in atmospheric properties that would be encountered in this application. This modification consisted of adding a variable density to the fluid based on the altitude of the node being calculated. This change in the way the code handled the fluid density had no effect on the method of calculation or any other factor related to the codes validation.

  5. Towed Articulated Housing For Geophysical Measurements

    NASA Technical Reports Server (NTRS)

    Burke, James D.; Cantrell, James

    1992-01-01

    Snakelike articulated string of rigid shells towed by helicopter, boat, kite or balloon, carries scientific instruments over land and sea surfaces. Nested shells connected to internal chain by bolt covered by preceding cone. String articulates readily to negotiate obstacles, but locally stiff to lie across a narrow crevasse.

  6. Acoustic-Sensing Underwater Tow Cable

    DTIC Science & Technology

    2013-09-30

    cable. The towed sensor system includes an array of hydrophones designed to sense a variety of underwater acoustic signals based on a particular...made from a flexible waterproof material such as polyurethane, nylon, or high-density polyethylene. The jacket 16 serves as the substrate for a...Encasing the regions 18, the conductors 20, as well as exposed portions of the jacket 16, is another waterproof jacket 22. The jacket 22 can be

  7. A Placement Advisory Test

    ERIC Educational Resources Information Center

    Hughes, Chris

    2010-01-01

    The primary method of placement at Portland CC (PCC) is the Compass Placement test. For the most part, students are placed correctly, but there are cases when students feel that they have been placed too low. In such cases we use our newly created Placement Advisory Test (PAT) to help us place them appropriately. (Contains 2 figures.)

  8. Fat-Line Towed-Array Force Measurement Apparatus

    DTIC Science & Technology

    2000-06-12

    No. 78872 n 3 FAT -LINE TOWED-ARRAY FORCE MEASUREMENT APPARATUS 4 5 STATEMENT OF GOVERNMENT INTEREST 6 The invention described herein may be...application. 16 17 BACKGROUND OF THE INVENTION 18 (1) Field of the Invention 19 The present invention relates generally to fat -line towed- 2 0 arrays, and...more particularly to an apparatus for measuring the 21 force applied to fat -line towed-arrays during flushing cycles. 22 (2) Description of the

  9. Investigations and Tests in the Towing Basin at Guidonia

    NASA Technical Reports Server (NTRS)

    Cremona, C

    1939-01-01

    The experimental methods at the Guidonia towing basin are discussed including specifications. Some of the components examined are the bridge towing carriage, side towing carriage, catapult installation, and dynamometer systems. Tests were performed on hulls and floats, as well as motor boats and torpedo shaped bodies. Theoretical investigations were also performed to determine pressure distributions on geometrically simple bodies, propagation of small wave motions, and planing and submerged surfaces.

  10. Computer-Aided Decision Making for Ocean Towing

    DTIC Science & Technology

    1989-05-12

    3 Resistance Prediction .............................................................................. 32 3.1 Tow Resistance...80,000 120,000 Wave Angle (deg) 0 60 120 180 Table 2.1. Data Base Towing Parameters. 31 Chapter 3 Resistance Prediction In order to use the extreme...this speed may be greater than or less than the desired tow speed. An exact solution is not computed because the accuracy of the resistance prediction methods

  11. Screw Placement and Osteoplasty Under Computed Tomographic-Fluoroscopic Guidance in a Case of Advanced Metastatic Destruction of the Iliosacral Joint

    SciTech Connect

    Trumm, Christoph Gregor; Rubenbauer, Bianca; Piltz, Stefan; Reiser, Maximilian F.; Hoffmann, Ralf-Thorsten

    2011-02-15

    We present a case of combined surgical screw placement and osteoplasty guided by computed tomography-fluoroscopy (CTF) in a 68-year-old man with unilateral osteolytic destruction and a pathological fracture of the iliosacral joint due to a metastasis from renal cell carcinoma. The patient experienced intractable lower back pain that was refractory to analgesia. After transarterial particle and coil embolization of the tumor-feeding vessels in the angiography unit, the procedure was performed under general anesthesia by an interdisciplinary team of interventional radiologists and trauma surgeons. Under intermittent single-shot CTF, two K wires were inserted into the left iliosacral joint from a lateral transiliac approach at the S1 level followed by two self-tapping surgical screws. Continuous CTF was used for monitoring of the subsequent polymethylmethacrylate injection through two vertebroplasty cannulas for further stabilization of the screw threads within the osteolytic sacral ala. Both the screw placement and cement injection were successful, with no complications occurring during or after the procedure. With additional nonsteroidal anti-inflammatory and opioid medication, the patient reported a marked decrease in his lower back pain and was able to move independently again at the 3-month follow-up assessment. In our patient with intolerable back pain due to tumor destruction and consequent pathological fracture of the iliosacral joint, CTF-guided iliosacral screw placement combined with osteoplasty was successful with respect to joint stabilization and a reduction in the need for analgesic therapy.

  12. Towed Twin-Fuselage Glider Launch System (CGI Animation Version 2)

    NASA Video Gallery

    The towed glider is an element of the novel rocket-launching concept of the Towed Glider Air-Launch System (TGALS). The TGALS demonstration’s goal is to provide proof-of-concept of a towed, airborn...

  13. Aerodynamics modeling of towed-cable dynamics

    SciTech Connect

    Kang, S.W.; Latorre, V.R.

    1991-01-17

    The dynamics of a cable/drogue system being towed by an orbiting aircraft has been investigated as a part of an LTWA project for the Naval Air Systems Command. We present here a status report on the tasks performed under Phase 1. We have accomplished the following tasks under Phase 1: A literature survey on the towed-cable motion problem has been conducted. While both static (steady-state) and dynamic (transient) analyses exist in the literature, no single, comprehensive analysis exists that directly addresses the present problem. However, the survey also reveals that, when judiciously applied, these past analyses can serve as useful building blocks for approaching the present problem. A numerical model that addresses several aspects of the towed-cable dynamic problem has been adapted from a Canadian underwater code for the present aerodynamic situation. This modified code, called TOWDYN, analyzes the effects of gravity, tension, aerodynamic drag, and wind. Preliminary results from this code demonstrate that the wind effects alone CAN generate the drogue oscillation behavior, i.e., the yo-yo'' phenomenon. This code also will serve as a benchmark code for checking the accuracy of a more general and complete R D'' model code. We have initiated efforts to develop a general R D model supercomputer code that also takes into account other physical factors, such as induced oscillations and bending stiffness. This general code will be able to evaluate the relative impacts of the various physical parameters, which may become important under certain conditions. This R D code will also enable development of a simpler operational code that can be used by the Naval Air personnel in the field.

  14. Vulcan: A deep-towed CSEM receiver

    NASA Astrophysics Data System (ADS)

    Constable, Steven; Kannberg, Peter K.; Weitemeyer, Karen

    2016-03-01

    We have developed a three-axis electric field receiver designed to be towed behind a marine electromagnetic transmitter for the purpose of mapping the electrical resistivity in the upper 1000 m of seafloor geology. By careful adjustment of buoyancy and the use of real-time monitoring of depth and altitude, we are able to deep-tow multiple receivers on arrays up to 1200 m long within 50 m of the seafloor, thereby obtaining good coupling to geology. The rigid body of the receiver is designed to reduce noise associated with lateral motion of flexible antennas during towing, and allows the measurement of the vertical electric field component, which modeling shows to be particularly sensitive to near-seafloor resistivity variations. The positions and orientations of the receivers are continuously measured, and realistic estimates of positioning errors can be used to build an error model for the data. During a test in the San Diego Trough, offshore California, inversions of the data were able to fit amplitude and phase of horizontal electric fields at three frequencies on three receivers to about 1% in amplitude and 1° in phase and vertical fields to about 5% in amplitude and 5° in phase. The geological target of the tests was a known cold seep and methane vent in 1000 m water depth, which inversions show to be associated with a 1 km wide resistor at a depth between 50 and 150 m below seafloor. Given the high resistivity (30 Ωm) and position within the gas hydrate stability field, we interpret this to be massive methane hydrate.

  15. 77 FR 12863 - Towing Safety Advisory Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... meeting of the Towing Vessel Inspection Work Group. The committee will reconvene on March 21, 2012. The meeting of the TSAC on both days and the meeting of the working group are open to the public. DATES: March... meeting of the Towing Vessel Inspection Work Group. March 21, 2012, the TSAC will reconvene 8:30 a.m. to...

  16. 33 CFR 83.24 - Towing and pushing (Rule 24).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... line above the sternlight; and (5) When the length of the tow exceeds 200 meters, a diamond shape where... exceeds 200 meters, a diamond shape where it can best be seen. (f) Vessels being towed alongside or pushed... alongside each other shall be lighted as one vessel or object; (4) A diamond shape at or near the...

  17. 33 CFR 83.24 - Towing and pushing (Rule 24).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... line above the sternlight; and (5) When the length of the tow exceeds 200 meters, a diamond shape where... exceeds 200 meters, a diamond shape where it can best be seen. (f) Vessels being towed alongside or pushed... alongside each other shall be lighted as one vessel or object; (4) A diamond shape at or near the...

  18. 33 CFR 83.24 - Towing and pushing (Rule 24).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... line above the sternlight; and (5) When the length of the tow exceeds 200 meters, a diamond shape where... exceeds 200 meters, a diamond shape where it can best be seen. (f) Vessels being towed alongside or pushed... alongside each other shall be lighted as one vessel or object; (4) A diamond shape at or near the...

  19. 33 CFR 83.24 - Towing and pushing (Rule 24).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... line above the sternlight; and (5) When the length of the tow exceeds 200 meters, a diamond shape where... exceeds 200 meters, a diamond shape where it can best be seen. (f) Vessels being towed alongside or pushed... alongside each other shall be lighted as one vessel or object; (4) A diamond shape at or near the...

  20. 15. VIEW NORTHNORTHEAST OF TOW TANK No. 2, DEWATERED. ENCLOSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. VIEW NORTH-NORTHEAST OF TOW TANK No. 2, DEWATERED. ENCLOSED AREAS AT BACK OF TUNNEL IS A HOUSING FOR CONDUCTING PERFORMANCE TESTING ON AIRCRAFT MODELS IN A VORTEX. - NASA Langley Research Center, Seaplane Towing Channel, 108 Andrews Street, Hampton, Hampton, VA

  1. Atropine Effects on the Operation of the Tow Missile Launcher.

    DTIC Science & Technology

    1987-03-01

    Missile Guidance Unit ( MGU ). The MGU operates in conjunction with the TOW sight to provide both azimuth (X) and elevation (Y) error signals. The operation...and Y error signals are then processed by the TOW’s MGU , digitized within the Apple by a 12-bit hybrid analog-to-digital converter and recorded on disk

  2. Engineered Polymer Composites Through Electrospun Nanofiber Coating of Fiber Tows

    NASA Technical Reports Server (NTRS)

    Kohlman, Lee W.

    2013-01-01

    Toughening and other property enhancements of composite materials are typically implemented by-modifying the bulk properties of the constituents, either the fiber or matrix materials. This often leads to difficulties in processing and higher material costs. Many composites consist of tows or yarns (thousands of individual fibers) that are either filament wound or processed into a fabric by weaving or braiding. The matrix material can be added to the tow or fabric before final processing, resulting in a prepreg material, or infused into the fiber material during final processing by a variety of methods. By using a direct electrospun deposition method to apply thermoplastic nanofiber to the surface of the tows, the tow-tow interface in the resulting composite can be modified while using otherwise conventional materials and handling processes. Other materials of interest could also be incorporated into the electrospun precursor.

  3. Preoperative Diagnostic Angiogram and Endovascular Aortic Stent Placement for Appleby Resection Candidates: A Novel Surgical Technique in the Management of Locally Advanced Pancreatic Cancer

    PubMed Central

    Trabulsi, N.; Pelletier, J. S.; Abraham, C.; Vanounou, T.

    2015-01-01

    Background. Pancreatic adenocarcinoma of the body and tail usually presents late and is typically unresectable. The modified Appleby procedure allows resection of pancreatic body carcinoma with celiac axis (CA) invasion. Given that the feasibility of this technique is based on the presence of collateral circulation, it is crucial to confirm the presence of an anatomical and functional collateral system. Methods. We here describe a novel technique used in two patients who were candidates for Appleby resection. We present their clinical scenario, imaging, operative findings, and postoperative course. Results. Both patients had a preoperative angiogram for assessment of anatomical circulation and placement of an endovascular stent to cover the CA. We hypothesize that this new technique allows enhancement of collateral circulation and helps minimize intraoperative blood loss when transecting the CA at its takeoff. Moreover, extra length on the CA margin may be gained, as the artery can be transected at its origin without the need for vascular clamp placement. Conclusion. We propose this novel technique in the preoperative management of patients who are undergoing a modified Appleby procedure. While further experience with this technique is required, we believe that it confers significant advantages to the current standard of care. PMID:26491217

  4. ADCP measurements from a towed fish

    NASA Astrophysics Data System (ADS)

    Kaneko, Arata; Koterayama, Wataru

    The acoustic Doppler current profiler (ADCP) is a powerful instrument that can measure detailed vertical profiles of ocean currents. ADCPs are often permanently mounted on research vessels and used to survey ocean currents rapidly over large areas of the ocean. We recently began development of a towed "fish" (instrument package) that would contain an ADCP with the same capabilities as a vessel-mounted ADCP but that would allow us greater flexibility and improved data. Here we describe our initial efforts, present some of our first results, and summarize our near-term plans for improving our present ADCP fish system. We are developing the ability to make ADCP measurements from a towed fish rather than from a ship because we want to be able to measure ocean currents accurately even under severe sea surface conditions,reduce the influence of cavitation noise generated by the ship's propeller,eliminate interference caused by bubbles entrained under the ship's hull, anduse the instrument on unspecified research ships.

  5. Towed and AUV Technologies for Arctic Operations

    NASA Astrophysics Data System (ADS)

    Singh, H.; Eustice, R.; Humphris, S.; Jakuba, M.; Kunz, C.; Murphy, C.; Nakamura, K.; Reves-Sohn, R.; Roman, C.; Sato, T.; Shank, T.; Willis, C.

    2007-12-01

    The 2007 AGAVE expedition included a suite of vehicles specifically designed and adapted for under-ice operations. These include the towed vehicle CAMPER, and the Puma and Jaguar autonomous underwater vehicles. The CAMPER (CAMera and samPlER) towed system was designed for high resolution imaging and sampling of the seafloor. It utilizes the oceanographic standard 0.68" electro-optical cable with three fibers and three copper conducting cables. The system consists of five cameras - a bottom looking high definition camera, a forward looking high definition camera system, a forward looking obstacle avoidance camera, a pan and tilt driving camera and a camera for instrumentation- and associated HMI and HID lighting systems. Sampling is accomplished by two hydraulically actuated systems. One of the samplers is a clam shell bucket design that is primarily intended for sampling rocks and sessile biological organisms. The other sampler uses a suction based mechanism and is intended for sampling fluids and motile biological organisms. The two AUVs, Puma and Jaguar, are identical in their base design but were outfitted with different sensor suites. These vehicles are a two hull design with most of the weight in the lower hull and most of the floatation in the top hull yielding a design that is passively stable in pitch and roll. Three thrusters, one for the vertical axis and two main thrusters allow for decoupled control in the vertical and horizontal axes. The 6 kWH battery packs are good for 24 hour operations. Both vehicles are equipped with acoustic modems, four channel long baseline receivers, doppler velocity logs, a high resolution depth sensor, three axes north seeking fiber optic gyroscopes and a pumped CTD. In addition, Puma, which is intended primarily for mid-water column work, also supports an Eh sensor, an optical backscatter sensor and an experimental long range optical backscatter sensor. The Jaguar vehicle, with a focus on near bottom measurements, is

  6. Aeroelastic Tailoring via Tow Steered Composites

    NASA Technical Reports Server (NTRS)

    Stanford, Bret K.; Jutte, Christine V.

    2014-01-01

    The use of tow steered composites, where fibers follow prescribed curvilinear paths within a laminate, can improve upon existing capabilities related to aeroelastic tailoring of wing structures, though this tailoring method has received relatively little attention in the literature. This paper demonstrates the technique for both a simple cantilevered plate in low-speed flow, as well as the wing box of a full-scale high aspect ratio transport configuration. Static aeroelastic stresses and dynamic flutter boundaries are obtained for both cases. The impact of various tailoring choices upon the aeroelastic performance is quantified: curvilinear fiber steering versus straight fiber steering, certifiable versus noncertifiable stacking sequences, a single uniform laminate per wing skin versus multiple laminates, and identical upper and lower wing skins structures versus individual tailoring.

  7. TOW Missile Pallet MIL-STD-1660 Tests

    DTIC Science & Technology

    1993-08-01

    0 DTICS ELECTE FEB 2 19941 FINAL REPORT C U ow AUGUST 1993 (V V Lfl3 NNE REPORT NO. 93-23 TOW MISSILE PALLET MIL- STD -1660 TESTS Prepared for...TITLE gOnakde Secwir Casaftedon) TOW Missile Pallet MIL- STD -1660 Tests 12. PERSONAL AUTHOR(S) Jason B. Solberg 13s. TYPE OF REPORT 13b. TIME COVERED...and Engineering Center (ARDEC) to test the TOW missile pallet. This report contains the procedures, results, and recommendations from the MIL- STD

  8. X-34 on lakebed prior to tow tests

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Following initial captive flight tests last year at NASA's Dryden Flight Research Center, Edwards Air Force Base, California, the X-34 technology demonstrator began a new series of tests last week in which it is being towed behind a semi-truck and released to coast on the Edwards dry lakebed. On July 20, 2000, it was towed and released twice at speeds of five and 10 miles per hour. On July 24, 2000, it was towed and released twice at 10 and 30 miles per hour. Twelve tests are planned during which the X-34 will be towed for distances up to 10,000 feet and released at speeds up to 80 miles per hour. The test series is expected to last at least six weeks.

  9. Composites from powder coated towpreg - Studies with variable tow sizes

    NASA Astrophysics Data System (ADS)

    Hugh, Maylene K.; Marchello, Joseph M.; Baucom, Robert M.; Johnston, Norman J.

    Part fabrication from composite materials usually costs less when larger fiber tow bundles are used. On the other hand, mechanical properties generally are lower for composites made using larger size tows. This situation gives rise to a choice between costs and properties in determining the best fiber tow bundle size to employ in preparing prepreg materials for part fabrication. To address this issue, unidirectional and eight harness satin fabric composite specimens were fabricated from 3k, 6k, and 12k carbon fiber reinforced LARC-TPI powder coated towpreg. Short beam shear strengths and longitudinal and transverse flexure properties were obtained for the unidirectional specimens. Tension properties were obtained for the eight harness satin woven towpreg specimens. Knowledge of the variation of properties with tow size may serve as a guide in material selection for part fabrication.

  10. Composites from powder coated towpreg - Studies with variable tow sizes

    NASA Technical Reports Server (NTRS)

    Hugh, Maylene K.; Marchello, Joseph M.; Baucom, Robert M.; Johnston, Norman J.

    1992-01-01

    Part fabrication from composite materials usually costs less when larger fiber tow bundles are used. On the other hand, mechanical properties generally are lower for composites made using larger size tows. This situation gives rise to a choice between costs and properties in determining the best fiber tow bundle size to employ in preparing prepreg materials for part fabrication. To address this issue, unidirectional and eight harness satin fabric composite specimens were fabricated from 3k, 6k, and 12k carbon fiber reinforced LARC-TPI powder coated towpreg. Short beam shear strengths and longitudinal and transverse flexure properties were obtained for the unidirectional specimens. Tension properties were obtained for the eight harness satin woven towpreg specimens. Knowledge of the variation of properties with tow size may serve as a guide in material selection for part fabrication.

  11. NASA Dryden Towed Glider Air-Launch Concept

    NASA Video Gallery

    NASA Dryden Flight Research Center is developing a novel space access, rocket launching technique called the Towed Glider Air-Launch Concept. The idea is to build a relatively inexpensive, remotely...

  12. 78 FR 14314 - Towing Safety Advisory Committee; Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-05

    ... and Recommendations for the Revision of NVIC 1-95, Voluntary Training Standards for Entry-Level..., Voluntary Training Standards for Entry-Level Personnel on Towing Industry Vessels. A final report will...

  13. M2-F1 under tow across lakebed by car

    NASA Technical Reports Server (NTRS)

    1963-01-01

    This 20-second clip shows the M2-F1 being towed by the Pontiac across Rogers Dry Lakebed. The M2-F1 lifting body, dubbed the 'flying bathtub' by the media, was the precursor of a remarkable series of wingless flying vehicles that contributed data used in the Space Shuttles, the X-33 Advanced Technology Demonstrator for the next century's Reusable Launch Vehicle, and the X-38 Technology Demonstrator for crew return from the International Space Station. Based on the ideas and basic design of Alfred J. Eggers and others at the Ames Aeronautical Laboratory (now the Ames Research Center), Mountain View, California, in the mid-1950's, the M2-F1 was built in 1962-63 over a four-month period for a cost of only about $30,000, plus an additional $8,000-$10,000 for an ejection seat. Engineers and technicians at the NASA Flight Research Center (now NASA Dryden) kept costs low by designing and fabricating it partly in-house, with the plywood shell constructed by a local sailplane builder. Someone at the time estimated that it would have cost a major aircraft company $150,000 to build the same vehicle. Unlike the later lifting bodies, the M2-F1 was unpowered and was initially towed by a souped-up Pontiac convertible until it was airborne. Later a C-47 took over the towing duties. Flown by such famous research pilots as Milt Thompson, Bruce Peterson, Chuck Yeager, and Bill Dana, the lightweight flying bathtub demonstrated that a wingless vehicle shaped for reentry into the Earth's atmosphere from space could be flown and landed safely. Flown from 1963 to 1966, the lightweight M2-F1 paved the way for the heavyweight M2-F2, M2`F3, HL-10, X-24A, and X-24B lifting bodies that flew under rocket power after launch from a B-52 mothership. The heavyweights flew from 1966 to 1975, demonstrating the viability and versatility of the wingless configuration and the ability of a vehicle with low lift-over-drag characteristics to fly to high altitudes and then to land precisely with their

  14. Method for Coating a Tow with an Electrospun Nanofiber

    NASA Technical Reports Server (NTRS)

    Kohlman, Lee W. (Inventor); Roberts, Gary D. (Inventor)

    2015-01-01

    Method and apparatus for enhancing the durability as well as the strength and stiffness of prepreg fiber tows of the sort used in composite materials are disclosed. The method involves adhering electrospun fibers onto the surface of such composite materials as filament-wound composite objects and the surface of prepreg fiber tows of the sort that are subsequently used in the production of composite materials of the filament-wound, woven, and braided sorts. The apparatus performs the methods described herein.

  15. An Acoustic Source Reactive to Tow Cable Strum

    DTIC Science & Technology

    2012-09-21

    shown in FIG. 3 in which the device is clamped to a tow cable 100 and which resembles a head mass of a Tonpilz transducer . The device 10 can be made of...steel or any other material appropriate for a transducer head mass. [0020] A Tonpilz transducer typically comprises a stack of piezoelectric...piezoelectric stack of a Tonpilz transducer that generates vibrational energy is replaced by the mile long tow cable 100 that generates vibrational

  16. ESL Placement and Schools

    PubMed Central

    Callahan, Rebecca; Wilkinson, Lindsey; Muller, Chandra; Frisco, Michelle

    2010-01-01

    In this study, the authors explore English as a Second Language (ESL) placement as a measure of how schools label and process immigrant students. Using propensity score matching and data from the Adolescent Health and Academic Achievement Study and the National Longitudinal Study of Adolescent Health, the authors estimate the effect of ESL placement on immigrant achievement. In schools with more immigrant students, the authors find that ESL placement results in higher levels of academic performance; in schools with few immigrant students, the effect reverses. This is not to suggest a one-size-fits-all policy; many immigrant students, regardless of school composition, generational status, or ESL placement, struggle to achieve at levels sufficient for acceptance to a 4-year university. This study offers several factors to be taken into consideration as schools develop policies and practices to provide immigrant students opportunities to learn. PMID:20617111

  17. Fiducial Marker Placement

    MedlinePlus

    ... Media Computed Tomography (CT) - Body General Ultrasound Ultrasound - Prostate Introduction to Cancer Therapy (Radiation Oncology) Proton Therapy Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT) Images related to Fiducial Marker Placement Sponsored by ...

  18. Gastrostomy tube placement - slideshow

    MedlinePlus

    ... presentations/100125.htm Gastrostomy tube placement - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  19. Investigation of the Forces Acting on Gliders in Automobile-pulley-winch and Airplane Towed Flight

    NASA Technical Reports Server (NTRS)

    Klemperer, W B

    1942-01-01

    The magnitude, the direction, and the fluctuation of towing forces exerted upon gliders by towing them aloft behind an automobile, by means of a winch, and by airplane were measured under a variety of conditions covering a range from gentle to severe types of operation. For these tests the towing forces did not exceed 92 percent of the gross weight of the glider. The results indicate that in pulley and winch towing the towing forces are of about the same magnitude as in automobile towing. Speed increases in the accelerated phases of the towing jerks encountered in airplane towing can readily become critical as speeds in excess of placard speeds can be attained. Passage through the slipstream of the towing airplane can be equivalent to a severe gust that, at high speed, may impose high wing loads and require large control moments.

  20. Curtiss JN-4H Towing Model Wing

    NASA Technical Reports Server (NTRS)

    1921-01-01

    In 1919 the NACA Langley laboratory received its first three research aircraft which were Curtiss JN-4Hs borrowed from the US Army Air Service at Langley Field. One of the first research projects of the laboratory initiated that year was a flight investigation of the lift and drag characteristics of the JN-4H. One of the objectives of the flight tests was to obtain data for correlation with wind-tunnel test results measured at MIT and to aid in the derivation of techniques for extrapolation of model results to full-scale conditions. In a pioneering aeronautical effort in 1920, pressure orifices were installed in the horizontal tail of one of the Jennies and connected to glass manometers for pressure measurements that could be photographed in flight. The NACA also used the aircraft in some of the earliest experiments on maneuverability in 1921. In addition to serving as test subjects, the aircraft were used for measurements of aerodynamic behavior of aircraft components. In this photograph made in 1921, one of the JN- 4Hs is towing a model of an aircraft wing to obtain lift and drag information for comparison to tunnel results. All three Jenny aircraft departed Langley in 1923. Reference: 'Flying the Frontiers: NACA and NASA Experimental Aircraft' by Arthur Pearcy. Naval Institute Press, 1993. ISBN 1-55750-258-7

  1. Tow collapse model for compression strength of textile composites

    SciTech Connect

    Emehel, T.C.; Shivakumar, K.N.

    1995-12-31

    The unidirectional composite compression strength model based on microbuckling of fibers embedded in a rigid-plastic matrix was extended to multiaxial laminates and textile composites. The resulting expression is a function of matrix yield strength under the fiber constraint, fiber misalignment angle, fiber volume fraction, and the area fractions of various sets of inclined tows. The analysis was verified by experimentation. Compression tests were conducted on laminated, three-dimensional triaxially braided and orthogonally woven composites using the IITRI test specimen. The laminate specimens were made up of AS4/3501-6 graphite/epoxy composite with (0){sub 24}, (0/30/0/{minus}30){sub 3S}, and ((0/90)6/0){sub S} stacking sequence. Textile composites were made of BASF G30-500 graphite fiber tows (tow size is 6K) and Dow Chemicals Tactix 123 matrix. Fiber preform architecture of braided and woven composites before resin consolidation was 0/{+-}17 and 0/90, respectively and after consolidation it was about (7/{+-}20) and (5/90/90), respectively. The analysis agreed reasonably well with the test data for all cases considered. The axial fiber/tow misalignment angle for laminated, braided, and woven composites were about 4, 7, and 5 degrees, respectively. The compression strength was found to be strongly dependent on the percentage of axial tows and its misalignment angle. A small variation in the off-axis fiber/tow orientation had marginal effect on the compression strength. Hence, the off axis tow misalignment angle can be assumed to be same as the initial laminate or the two orientation angle.

  2. Drag Characteristics of Several Towed Decelerator Models at Mach 3

    NASA Technical Reports Server (NTRS)

    1970-01-01

    Drag Characteristics of Several Towed Decelerator Models at Mach 3. An investigation has been made to determine the possibility of using toroid-membrane and wide-angle conical shapes as towed decelerators. Parameter variations were investigated which might render toroid-membrane models and wide-angle- cone models stable without loss of the high drag coefficients obtainable with sting-mounted models. The parameters varied included location of center of gravity, location of the pivot between the towline and the model, and configuration modifications of the aft end as the addition of a corner radius and the addition of a skirt. The toroid membrane can be made into a stable towed decelerator with a suitable configuration modification of the aft end. [Entire movie available on DVD from CASI as Doc ID 20070031013. Contact help@sti.nasa.gov

  3. Models in towing basins/design of floats for seaplanes

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Towing carriage gear housing in the Tow Tank. Starr Truscott described the Towing Carriage in NACA TR No. 470: ' The structure of the towing carriage is of carbon-steel tube, with all joints welded. In order to insure accuracy of alinement (sic.) in the girders forming the car structure, the ends of all the tubes meeting at a joint were milled to fit snugly before welding and all welding was done with the structure in a massive jig. The gear cases also are of welded construction.' (p. 537) The Tow Tank was designed by Starr Truscott. Construction was authorized in March 1929 and was dedicated on May 27, 1931 during the Annual Manufacturer's Inspection meeting. The tank's initial cost was $649,000. It was used by the NACA to study hydrodynamics problems until 1959 when the facility was turned over to the U.S. Navy. The tank was extended to 2960 in 1936. In addition to increasing the length of the tank, a new high-speed (80-mph) carriage was installed in 1936-1937.Construction of pontoon hull model to be tested in Tow Tank No. 1. This is a 1/6 full size model of the hull of a Navy PH-1 flying boat. Two typical tests were conducted and included in the first report describing the High-Speed Towing Basin. From TR 470: 'A survey of the information available regarding the application of the results of tests of models in towing basins to the design of floats for seaplanes was made by the National Advisory Committee for Aeronautics in 1929. It was found that the development of flying boats and seaplanes had been assisted very much in the United States, and possibly more in other countries, by tests of models in towing basins or tanks. Some tanks already existed which were designed especially for testing models of seaplane floats and the construction of other tanks for this special purpose was projected. There was no such tank in the United States; in fact, there were only two tanks, both constructed before the appearance of the seaplane and designed originally to test

  4. Air-Sea Interaction Measurements from the Controlled Towed Vehicle

    NASA Astrophysics Data System (ADS)

    Khelif, D.; Bluth, R. T.; Jonsson, H.; Barge, J.

    2014-12-01

    The Controlled Towed Vehicle (CTV) uses improved towed drone technology to actively maintain via a radar altimeter and controllable wing a user-set height that can be as low as the canonical reference height of 10 m above the sea surface. After take-off, the drone is released from the tow aircraft on a ~700-m stainless steel cable. We have instrumented the 0.23 m diameter and 2.13 m long drone with high fidelity instruments to measure the means and turbulent fluctuations of 3-D wind vector, temperature, humidity, pressure, CO2 and IR sea surface temperature. Data are recorded internally at 40 Hz and simultaneously transmitted to the tow aircraft via dedicated wireless Ethernet link. The CTV accommodates 40 kg of instrument payload and provides it with 250 W of continuous power through a ram air propeller-driven generator. Therefore its endurance is only limited by that of the tow aircraft.We will discuss the CTV development, the engineering challenges and solutions that have been successfully implemented to overcome them. We present results from recent flights as low as 9 m over the coastal ocean and comparisons of profiles and turbulent fluxes from the CTV and the tow aircraft. Manned aircraft operation at low-level boundary-layer flights is very limited. Dropsondes and UAS (Unmanned Aerial Systems) and UAS are alternates for measurements near the ocean surface. However, dropsondes have limited sensor capability and do not measure fluxes, and most present UAS vehicles do not have the payload and power capacity nor the low-flying ability in high winds over the oceans. The CTV therefore, fills a needed gap between the dropsondes, in situ aircraft, and UAS. The payload, capacity and power of the CTV makes it suitable for a variety of atmospheric research measurements. Other sensors to measure aerosol, chemistry, radiation, etc., could be readily accommodated in the CTV.

  5. Instrumentation requirements for small scale towed temperature measurements

    NASA Astrophysics Data System (ADS)

    Dugan, J. P.; Morris, W. D.

    1984-03-01

    Measurements of horizontal ocean temperature structure are difficult to obtain by towing sensors from research vessels because the tow cable induces sensor platform motions which contaminate the data. In this report, temperature data which previously were acquired in the thermocline with special care are used to specify the acceptable level of motion and to prescribe appropriate sensor noise levels. In the swell-induced ship motion band, for example, the rms vertical displacements of the sensors should be less than several centimeters and temperature sensors should resolve fluctuations of one millidegree Celsius in regions of high (approx 0.1 C/m) temperature gradient.

  6. College Placement in Today's Economy.

    ERIC Educational Resources Information Center

    Galloway, James L.

    1982-01-01

    Analyzed the effects of reduced financing on college placement items such as services, staffing, fees, conference attendance, travel, recruitment, and salaries. Placement personnel (N=224) responded to a questionnaire. Results indicated that budgets have generally remained the same. (RC)

  7. 49 CFR 393.71 - Coupling devices and towing methods, driveaway-towaway operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ball-and-socket type coupling device may be used in any combination. (3) When motor vehicles are towed... motor vehicle or motor vehicles may be full-mounted on the structure of a towing vehicle engaged in any... motor vehicle or motor vehicles may be full-mounted on the structure of towed vehicles engaged in...

  8. 49 CFR 393.70 - Coupling devices and towing methods, except for driveaway-towaway operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Coupling devices and towing methods, except for... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.70 Coupling devices and towing methods, except for driveaway-towaway operations....

  9. 49 CFR 393.71 - Coupling devices and towing methods, driveaway-towaway operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Coupling devices and towing methods, driveaway... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.71 Coupling devices and towing methods, driveaway-towaway operations. (a) Number in...

  10. 49 CFR 393.70 - Coupling devices and towing methods, except for driveaway-towaway operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Coupling devices and towing methods, except for... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.70 Coupling devices and towing methods, except for driveaway-towaway operations....

  11. 49 CFR 393.71 - Coupling devices and towing methods, driveaway-towaway operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Coupling devices and towing methods, driveaway... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.71 Coupling devices and towing methods, driveaway-towaway operations. (a) Number in...

  12. 49 CFR 393.70 - Coupling devices and towing methods, except for driveaway-towaway operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Coupling devices and towing methods, except for... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.70 Coupling devices and towing methods, except for driveaway-towaway operations....

  13. 49 CFR 393.70 - Coupling devices and towing methods, except for driveaway-towaway operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Coupling devices and towing methods, except for... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Coupling Devices and Towing Methods § 393.70 Coupling devices and towing methods, except for driveaway-towaway operations....

  14. 46 CFR 11.464 - Requirements for endorsements as master of towing vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Requirements for endorsements as master of towing....464 Requirements for endorsements as master of towing vessels. (a) If you would like to obtain an endorsement as master of towing vessels with a route listed in column 1 of table 11.464(a) of this...

  15. Reduced toxicity polyester resins and microvascular pre-preg tapes for advanced composites manufacturing

    NASA Astrophysics Data System (ADS)

    Poillucci, Richard

    Advanced composites manufacturing broadly encapsulates topics ranging from matrix chemistries to automated machines that lay-up fiber-reinforced materials. Environmental regulations are stimulating research to reduce matrix resin formulation toxicity. At present, composites fabricated with polyester resins expose workers to the risk of contact with and inhalation of styrene monomer, which is a potential carcinogen, neurotoxin, and respiratory irritant. The first primary goal of this thesis is to reduce the toxicity associated with polyester resins by: (1) identification of potential monomers to replace styrene, (2) determination of monomer solubility within the polyester, and (3) investigation of approaches to rapidly screen a large resin composition parameter space. Monomers are identified based on their ability to react with polyester and their toxicity as determined by the Globally Harmonized System (GHS) and a green screen method. Solubilities were determined by the Hoftyzer -- Van Krevelen method, Hansen solubility parameter database, and experimental mixing of monomers. A combinatorial microfluidic mixing device is designed and tested to obtain distinct resin compositions from two input chemistries. The push for safer materials is complemented by a thrust for multifunctional composites. The second primary goal of this thesis is to design and implement the manufacture of sacrificial fiber materials suitable for use in automated fiber placement of microvascaular multifunctional composites. Two key advancements are required to achieve this goal: (1) development of a roll-to-roll method to place sacrificial fibers onto carbon fiber pre-preg tape; and (2) demonstration of feasible manufacture of microvascular carbon fiber plates with automated fiber placement. An automated method for placing sacrificial fibers onto carbon fiber tapes is designed and a prototype implemented. Carbon fiber tows with manual placement of sacrificial fibers is implemented within an

  16. 20. VIEW TO WEST OF INTERIOR OF CRANEWAY WITH TOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. VIEW TO WEST OF INTERIOR OF CRANEWAY WITH TOW TRAVELING BRIDGE CRANES (ONE OVERHEAD IN FOREGROUND AND ONE OVERHEAD IN BACKGROUNDS). NOTE WOOD BLOCK PAVING ON THE FLOOR. FIRST FLOOR ASSEMBLY AREA IS THE SPACE IN THE BACKGROUND ON THE RIGHT. - Rosie the Riveter National Historical Park, Ford Assembly Plant, 1400 Harbour Way South, Richmond, Contra Costa County, CA

  17. 76 FR 59415 - Towing Safety Advisory Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... public meeting on Thursday, October 20, 2011, in Newport News, Virginia. Two TSAC sub-committees will meet the day before, October 19, 2011. DATES: Two Towing Safety Advisory Committee Sub-committees will... and local government jurisdictions in compliance with FACA. Agenda--October 19, 2011 TSAC...

  18. Field experiments on an intelligent towed vehicle ``Flying Fish``

    SciTech Connect

    Koterayama, W.; Yamaguchi, S.; Nakamura, M.

    1995-12-31

    A depth, pitch and roll controllable towed vehicle, ``Flying Fish`` is being developed to measure the ocean current, temperature, salinity, dissolved oxygen, pH, turbidity, chlorophyll and total inorganic hydrocarbon. The first field experiments on its performance were carried out in the Japan sea last summer. The motion data of the ``Flying Fish`` are compared with those of numerical simulations.

  19. 75 FR 20856 - Towing Safety Advisory Committee; Vacancies

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... Advisory Committee (TSAC). This Committee advises the Coast Guard on matters relating to shallow-draft... authority of 33 U.S.C. 1231a and advises the Secretary of Homeland Security on matters relating to shallow... from the Barge and Towing industry (reflecting a regional geographical balance); 1 member from...

  20. 78 FR 20684 - Towing Safety Advisory Committee; Vacancies

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... SECURITY Coast Guard Towing Safety Advisory Committee; Vacancies AGENCY: United States Coast Guard. ACTION: Request for applications. SUMMARY: The United States Coast Guard (the Coast Guard) is requesting... Safety Advisory Committee (TSAC). TSAC advises the Coast Guard on matters relating to shallow-...

  1. Full Scale Wind Tunnel and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Construction progress, aerials of East Area. L5169: Langley's seaplane towing facility (right) and the Full Scale Tunnel (left) were photographed in November of 1930. Photograph published in Winds of Change, 75th Anniversary NASA publication (page 39), by James Schultz.

  2. 33 CFR 164.78 - Navigation under way: Towing vessels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under...

  3. 33 CFR 164.78 - Navigation under way: Towing vessels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under...

  4. 33 CFR 164.78 - Navigation under way: Towing vessels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under...

  5. 33 CFR 164.78 - Navigation under way: Towing vessels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under...

  6. 33 CFR 164.78 - Navigation under way: Towing vessels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under...

  7. 18. VIEW OF BALES OF CEDAR TOW (CEDAR SHAVING WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. VIEW OF BALES OF CEDAR TOW (CEDAR SHAVING WITH SAWDUST TUMBLED OUT) SOLD FOR GARDEN AND ANIMAL BEDDING, AND OTHER AGRICULTURAL USES; TUMBLER IS CYLINDRICAL MACHINE TO LEFT - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

  8. Impacted material placement plans

    SciTech Connect

    Hickey, M.J.

    1997-01-29

    Impacted material placement plans (IMPP) are documents identifying the essential elements in placing remediation wastes into disposal facilities. Remediation wastes or impacted material(s) are those components used in the construction of the disposal facility exclusive of the liners and caps. The components might include soils, concrete, rubble, debris, and other regulatory approved materials. The IMPP provides the details necessary for interested parties to understand the management and construction practices at the disposal facility. The IMPP should identify the regulatory requirements from applicable DOE Orders, the ROD(s) (where a part of a CERCLA remedy), closure plans, or any other relevant agreements or regulations. Also, how the impacted material will be tracked should be described. Finally, detailed descriptions of what will be placed and how it will be placed should be included. The placement of impacted material into approved on-site disposal facilities (OSDF) is an integral part of gaining regulatory approval. To obtain this approval, a detailed plan (Impacted Material Placement Plan [IMPP]) was developed for the Fernald OSDF. The IMPP provides detailed information for the DOE, site generators, the stakeholders, regulatory community, and the construction subcontractor placing various types of impacted material within the disposal facility.

  9. Advanced Placement and College Credit. Policy Brief

    ERIC Educational Resources Information Center

    Spaulding, Randy

    2011-01-01

    Washington's 2008 Strategic Master Plan for Higher Education called for creating "multiple pathways from high school to college or workforce training" --through greater use of dual credit and concurrent high school and college enrollment options. The most prevalent of these in Washington are Running Start, which accounts for 12,500 FTE;…

  10. Advanced Placement Program at Palo Verde College.

    ERIC Educational Resources Information Center

    Twitchell, Theodore G.

    This study reports the outcome of an initial implementation of a California law permitting mentally gifted high school students to attend a junior college part time. The program procedure is described in terms of (1) selection and enrollment, (2) discipline, (3) books, (4) matters relating to high school graduation, (5) information for parents,…

  11. Thermomechanical Characterization of SiC Fiber Tows and Implications for CMC

    NASA Technical Reports Server (NTRS)

    Yun, H. M.; DiCarlo, J. A.

    1999-01-01

    In order to better understand SiC fiber behavior within CMC microstructures, mechanical tests were performed on multifilament tows consisting of different types of as produced and pretreated fibers. Tensile strengths of tows and single fibers were measured at room temperature for nonstoichiometric Hi-Nicalon and ZMI fibers and for stoichiometric Hi-Nicalon-S, Tyranno SA. and Sylramic fibers. Based on simple bundle theory, measured strengths for as-produced and sized tows were in general agreement with the single fiber results. However, after sizing removal under inert conditions, tow strengths for the coarser grained stoichiometric fibers were typically lower than those predicted from individual fiber data. This effect is attributed to enhanced fiber-fiber mechanical interaction caused by sizing removal from the rough surfaces of these fibers. In support of this, tow strengths remained high for those fiber types with fine grains or excess surface carbon; and, when re-coated with a BN interphase coating, tow strengths for the coarser grained fibers returned to their as-produced values. When the tows were pretreated in air at intermediate temperatures, tow strengths decreased in a manner that could be correlated with the oxidation characteristics of each fiber type as measured by thermogravimetric analysis. The creep and rupture properties of Hi-Nicalon and Sylramic tows were also measured in air and argon from 1200 to 1400 C. Although displaying transient and environmental effects similar to single fibers, the tows crept faster at short times and slower at long times. This resulted in the tow rupture strengths at long time being much greater than the rupture strengths of single fibers. The CMC implications of the tow results are discussed, as well as the benefits and limitations of tow testing.

  12. A towed airborne platform for turbulence measurements over the ocean

    NASA Astrophysics Data System (ADS)

    Friehe, Carl; Khelif, Djamal

    2008-11-01

    Measurements of wind stress and associated heat and mass fluxes (water vapor and CO2) down to ˜10 meters height over the ocean are required to establish parameterizations for wave, weather, hurricane and climate models. At high winds and accompanying sea states, such measurements are difficult or impossible. A new airborne instrumented towed platform has been developed that allows measurements down to 10 meters under radar-altitude control while the tow aircraft is safely above. Measurements include the three components of the wind, temperature, humidity, infrared surface temperature, CO2, and motion and navigational parameters. The bandwidth of the sensors allows calculation of the Reynolds averaged covariance's of stress and sensible heat and evaporation fluxes. Results are compared to equivalent measurements made with an instrumented aircraft. We would like to thank Robert Bluth of the Naval Postgraduate School and Jesse Barge and Dan Bierly of Zivko Aeronautics.

  13. Optimizing an undulating magnetic microswimmer for cargo towing.

    PubMed

    Gutman, Emiliya; Or, Yizhar

    2016-06-01

    One of the promising capabilities of magnetic microswimmers is towing a cargo, which can be used for targeted drug delivery or performing tissue biopsy. A key question is what should be the optimal size ratio between the cargo and the swimmer's flexible tail. This question is addressed here for the simplest theoretical model of a magnetic microswimmer undergoing planar undulations-a spherical load connected by a torsion spring to a rigid slender link. The swimmer's dynamic is formulated and leading-order expressions for its motion are obtained explicitly under small-amplitude approximation. Optimal combinations of magnetic actuation frequency, torsion stiffness, and tail length for maximizing displacement, average speed, or energetic efficiency are obtained. The theoretical results are compared with reported experiments in several types of cargo-towing magnetic microswimmers.

  14. Optimizing an undulating magnetic microswimmer for cargo towing

    NASA Astrophysics Data System (ADS)

    Gutman, Emiliya; Or, Yizhar

    2016-06-01

    One of the promising capabilities of magnetic microswimmers is towing a cargo, which can be used for targeted drug delivery or performing tissue biopsy. A key question is what should be the optimal size ratio between the cargo and the swimmer's flexible tail. This question is addressed here for the simplest theoretical model of a magnetic microswimmer undergoing planar undulations—a spherical load connected by a torsion spring to a rigid slender link. The swimmer's dynamic is formulated and leading-order expressions for its motion are obtained explicitly under small-amplitude approximation. Optimal combinations of magnetic actuation frequency, torsion stiffness, and tail length for maximizing displacement, average speed, or energetic efficiency are obtained. The theoretical results are compared with reported experiments in several types of cargo-towing magnetic microswimmers.

  15. A space tethered towing method using tension and platform thrusts

    NASA Astrophysics Data System (ADS)

    Meng, Zhongjie; Wang, Bingheng; Huang, Panfeng

    2017-01-01

    Orbit maneuver via tether is a promising countermeasure for space debris removal and satellite orbit transfer. A space tethered towing method is explored that utilizes thrust to fulfill transfer and bounded tension to stabilize tether heading. For this purpose, a time-energy optimal orbit is designed by Gauss pseudospectral method. The theoretical attitude commands are obtained by equilibria analysis. An effective attitude control strategy is presented where the commands are optimized first and then feedback controller is designed. To deal with the underactuated problem with tension constraint, hierarchical sliding mode theory is employed and an adaptive anti-windup module is added to mitigate the actuator saturation. Simulation results show that the target is towed effectively by the thrusts, and a smooth tracking for the commands of tether length and in-plane tether heading is guaranteed by the bounded tension. In addition, the designed controller also presents appreciable robustness to model error and determination error.

  16. Fractional-step Tow-Thomas biquad filters

    NASA Astrophysics Data System (ADS)

    Freeborn, Todd J.; Maundy, Brent; Elwakil, Ahmed

    In this paper we propose the use of fractional capacitors in the Tow-Thomas biquad to realize both fractional lowpass and asymmetric bandpass filters of order 0<α1+α2≤2, where α1 and α2 are the orders of the fractional capacitors and 0<α1,2≤1. We show how these filters can be designed using an integer-order transfer function approximation of the fractional capacitors. MATLAB and PSPICE simulations of first order fractional-step low and bandpass filters of order 1.1, 1.5, and 1.9 are given as examples. Experimental results of fractional low pass filters of order 1.5 implemented with silicon-fabricated fractional capacitors verify the operation of the fractional Tow-Thomas biquad.

  17. 7. View showing placement of timber deck placement on chord ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View showing placement of timber deck placement on chord and built up construction of top chord and continuous construction through top panel points, eye bar construction on bottom chord - Bridge No. 2.4, Spanning Boiling Fork Creek at Railroad Milepost JC-2.4, Decherd, Franklin County, TN

  18. Optimizing an undulating magnetic microswimmer for cargo towing

    NASA Astrophysics Data System (ADS)

    Or, Yizhar; Gutman, Emiliya

    2015-11-01

    One of the promising applications of robotic microswimmers is towing a cargo for controlled drug delivery, micro-surgery or tumor detection. This capability has been demonstrated by the magnetically-actuated microswimmer of Dreyfus et al. [Nature 2005] in which a red blood cell was attached to a chain of magnetic beads connected by flexible DNA links. A key question is what should be the optimal size of the magnetic tail for towing a given cargo. This question is addressed here for the simplest theoretical model of a magnetic microswimmer under planar undulations - a spherical load connected by a torsion spring to a magnetized rigid slender link. The swimmer's dynamics is formulated assuming negligible hydrodynamic interaction and leading-order expressions for the resulting motion are obtained explicitly under small amplitude approximation. Optimal combinations of magnetic actuation frequency, torsion stiffness, and tail length for maximizing displacement or average speed are obtained. The theoretical results are compared with several reported magnetic microswimmers, and also agree qualitatively with recent results on cargo towing by screw rotation of magnetic helical tails [Walker et al., ACS Nano Letters 2015]. This work is supported by the Israeli Science Foundation (ISF) under Grant No. 567/14.

  19. M2-F1 in hangar with Pontiac tow vehicle

    NASA Technical Reports Server (NTRS)

    1963-01-01

    The M2-F1 Lifting Body is seen here in a hangar with its hotrod Pontiac convertible tow vehicle at the Flight Research Center (later the Dryden Flight Research Center), Edwards, California. The car was a 1963 Pontiac Catalina convertible, fitted with a 421-cubic-inch tripower engine like those being run at the Daytona 500 auto race. The vehicle also had a four-speed transmission and a heavy-duty suspension and cooling system. A roll bar was also added and the passenger seat turned around so an observer could watch the M2-F1 while it was being towed. The rear seat was removed and a second, side-facing seat installed. The lifting-body team used the Pontiac for all the ground-tow flights over the next three years. The wingless, lifting body aircraft design was initially conceived as a means of landing an aircraft horizontally after atmospheric reentry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Dryden management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a 'flying bathtub,' and was designated the M2-F1, the 'M' referring to 'manned' and 'F' referring to 'flight' version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds up to about 120 mph. This vehicle needed to be able to tow the M2-F1 on the Rogers Dry Lakebed adjacent to NASA's Flight Research Center (FRC) at a minimum speed of 100 miles per hour. To do that, it had to handle the 400-pound pull of the M2-F1. Walter 'Whitey' Whiteside, who was a retired Air Force maintenance officer working in the FRC's Flight Operations Division, was a dirt-bike rider and hot-rodder. Together with Boyden 'Bud' Bearce in the Procurement and Supply Branch of the FRC, Whitey

  20. Surface Towed CSEM Systems for Shallow Water Mapping

    NASA Astrophysics Data System (ADS)

    Sherman, J.; Constable, S.; Kannberg, P. K.

    2015-12-01

    We have developed a low-power, surface towed electric dipole-dipole system suitable for mapping seafloor geology in shallow water and deployable from small boats. The transmitter is capable of up to 50 amps output using 12 VDC from a 110/240 VAC power supply, and can generate an arbitrary GPS stabilized ternary waveform. Transmitter antennas are typically 50 to 100 m long. Receivers are built around the standard Scripps seafloor electrode, amplifier, and logging systems but housed in floating PVC cases and equipped with GPS timing and positioning, pitch/roll/heading sensors, and accelerometers. Receiver dipoles are 1.5 m long rigid booms held 1 m below the surface. As with the Scripps deep-towed Vulcan system, rigid antennas are used to avoid noise associated with flexible antennas moving across Earth's magnetic field. The tow cable is a simple floating rope up to 1000 m long. Water depth and conductivity are sampled continuously in order to provide constraints for apparent resistivity calculations and inversion, and moored seafloor recorders can be used to extend transmitter/receiver offsets. The entire system can be air freighted and transported in one utility vehicle. We will present results from a study to map permafrost in shallow water off Prudhoe Bay, Alaska.

  1. MAPP: A Mathematics Placement Program.

    ERIC Educational Resources Information Center

    Doblin, Stephen A.

    1978-01-01

    MAPP (A Mathematics Placement Program) uses two COBOL programs to place entering freshmen in mathematics courses which are commensurate with their backgrounds and abilities. Having been used for three years, the program is considered to be a viable alternative to the traditional mathematics placement process. (Author/JKS)

  2. [Developmental Placement.] Collected Research References.

    ERIC Educational Resources Information Center

    Bjorklund, Gail

    Drawing on information and references in the ERIC system, this literature review describes research related to a child's developmental placement. The issues examined include school entrance age; predictive validity, reliability, and features of Gesell School Readiness Assessment; retention; and the effectiveness of developmental placement. A…

  3. Improvement of Job Placement Services.

    ERIC Educational Resources Information Center

    Mount San Antonio Community Coll. District, Walnut, CA.

    The Improvement of Job Placement Services Project was undertaken to examine and strengthen job placement services and programs in the California community colleges. Specific objectives of the project were to: (1) select and convene a 12-member representative advisory committee to oversee project operations working with the California Placement…

  4. Placement and Follow-up.

    ERIC Educational Resources Information Center

    Shippen, Samuel Joseph, Ed.; Wasil, Raymond A., Ed.

    This document contains a compilation of original manuscripts written by competent authorities in the field of job placement services for students. Viewing placement as both a product and an integral part of a developmental process, these papers are divided into the following six topical areas: (1) information, (2) exploration, (3) counseling, (4)…

  5. College Student Personnel Graduate Placement

    ERIC Educational Resources Information Center

    Greer, Richard M.; And Others

    1978-01-01

    This study reports results of ACPA Commission XII's survey of 101 college student personnel training institutions regarding their graduate placement. Graduates were identified according to degree, race, and sex. Percentages of graduates placed, specialty areas, types of institutions, areas of the country, and time and method of placement were…

  6. Early Results from the IMI-30 Towed Sonar System

    NASA Astrophysics Data System (ADS)

    Edwards, M. H.; Rognstad, M. R.; Tottori, S. N.; Davis, R. B.; Appelgate, T. B.; Johnson, P. D.; Kevis-Stirling, A.

    2006-12-01

    The Hawaii Mapping Research Group (HMRG) of the University of Hawaii has designed and built a 30 kHz deep-towed sonar, the IMI-30, which simultaneously collects interferometric bathymetry and backscatter data. The sonar is capable of being deployed to 6000 m water depth, where it is towed 100-500 m above the seafloor yielding a total swath width of 1-5 km for sidescan and somewhat less than that for bathymetry. The across-track resolution is <10 m for bathymetry depending on towing geometry and substrate type, and 0.3- 3 m for sidescan, depending on the selected transmit pulse length and tow vehicle altitude. The along-track resolution, which is dependent on vehicle speed and pulse repetition rate, varies between 0.6 and 3 meters. Here we report on data collected by the system during two different deployments in the Pacific: the IMI-30's initial field program in the Lau Basin in 2004 and the most recent survey using the system, south of Oahu in June of 2006. Between the 2004 Lau program and the June 2006 survey, several engineering improvements were made including: 1) changing the housings of the side-looking transducers from cast polyurethane to oil- filled polyethylene; 2) adding syntactic foam baffling to reduce surface bounce; 3) synchronizing sound velocimeter measurements with sonar transmit; 4) adding sub-bottom transducers and associated electronics to the tow vehicle; 5) adding two additional side-looking transducer rows per side, and 6) upgrading the surface and subsurface power supplies. This engineering effort has improved reliability of the system by eliminating transducer failures caused by seawater leakage and power supply over-temperature shutdown in tropical waters. Reducing the system noise - electrical, hydrodynamic, and acoustic - has improved data quality and extended the swath width. The addition of sub-bottom data acquisition further increases the utility of the IMI-30 system. Our presentation will document the engineering effort and

  7. Full Scale Tunnel (FST) and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Installation of Careystone covering at the Full-Scale Tunnel (FST) facility. The corrugated concrete and asbestos panels (1/4 inch thick; 42 inches wide; 62 inches long) which were used as siding and roofing for the Full-Scale Tunnel were manufactured by The Philip Carey Company. For the NACA, the choice of Careystone had been based on several factors. First and foremost was its low cost. NACA engineers had observed the very durable, low-maintenance and fireproof qualities of the concrete-asbestos covering of the airship hanger at Langley Field. Further, tests showed the material to be 3.8 times stronger than required (The maximum load the material was expected to withstand was 52 lbs. per square foot; the breaking load was 196 lbs. per sq. ft.). L4695 shows the interior view of construction of the Tow Tank. In the late 1920s, the NACA decided to investigate the aero/hydro dynamics of floats for seaplanes. A Hydrodynamics Branch was established in 1929 and special towing basin was authorized in March of that same year. Starr Truscott (the first head of the new division) described the tank in NACA TR 470: 'The N.A.C.A. tank is of the Froude type; that is, the model which is being tested is towed through still water at successive constant speeds from a carriage spanning the tank. At each constant speed the towing pull is measured, the trim and the rise, or change of draft, are recorded and, if the model is being towed at a fixed trim, the moment required to hold it there is measured and recorded.' 'The reinforced concrete basin containing the water has the following dimensions: (1) Length on water, extreme, 2,020 feet; (2) Normal width of water surface, 24 feet; (3) Normal depth of water, 12 feet; (4) Length of 12 foot depth, 1,980 feet.' This picture shows the tank before the coving was added. This brought the rails for the carriage closer together and helped suppress waves produced by the models. The finished tank would be filled with approximately 4 million

  8. Method and apparatus for deregistering multi-filament tow and product thereof

    DOEpatents

    Lukhard, Craig R.; Potter, Jerry F.; Todd, Maurice C.

    1995-01-01

    A method and apparatus for deregistering drawn crimped nylon multifilament tow includes the steps of stretching the tow under constant controlled tension at a temperature below the glass transition temperature of the nylon. The apparatus includes means for sensing the tension of the tow between the feed and draw sections of a stretching device and producing a signal representative of the tension sensed and a controller for changing the speed of the draw section actuated by said signal.

  9. The Status of Infantry TOW, LAW, and Dragon Training in USAREUR.

    DTIC Science & Technology

    1977-11-01

    and 100% of squad leaders. On any given day, an estimated one-third of personnel were unavailable for train- ing. Some CONUS-trained TOW gunners were...not assigned to TOW squads . LAW On any given day, an estimated 20% were unavailable for training. Dragon No personnel problems were apparent. Gunners...amount of gunner and squad training. Most gunners received intensive training only in preparation for annual live firing. Most TOW squads had no

  10. A Method to Estimate Local Towed Array Angles Using Flush Mounted Hot Film Wall Shear Sensors

    DTIC Science & Technology

    2008-06-05

    during turns. In the invention, a flush mounted hot film sensor and an anemometry system are used to measure the mean and fluctuating turbulent wall...decrease in towing speed necessitated by certain maneuvers can cause the towed array to fall or sink. Suitable flush mounted hot film sensors and anemometry ...the calculated shaped of the deployed towed array 100 and the physical restraints of incorporating the hot -film sensors 108 and associated wiring into

  11. Towing tank tests for surface combatant for coupled pitch and heave and free roll decay motions

    NASA Astrophysics Data System (ADS)

    Irvine, Martin, Jr.

    Towing-tank experiments are performed for an advancing surface combatant in free roll decay and coupled pitch and heave motions. For free roll decay experiments, results are presented for motions (surge, sway, heave, roll, pitch and yaw), forces (resistance, sway and heave), moments (pitch and yaw), phase-averaged velocities (U, V and W) for measurement region near bilge keel and free surface elevations. For coupled pitch and heave experiments, results are presented for pitch and heave transfer functions, and pitch and heave phase angles. The geometry of interest is DTMB model 5512, which is a 1/46.6 scale geosym of DTMB model 5415 (DDG-51), with L = 3.048 m. The experiments are performed in a 3 x 3 x 100m towing tank equipped with a plunger-type wavemaker. The measurement systems include Krypton contactless motion tracker, 4-component load cell, towed 2-D particle image velocimetry (PIV) system, and servo wave probes with 2-D traverse. Uncertainty assessment following standard procedures is used to evaluate the quality of the data. Pitch and heave transfer functions and phase angles collapse to a single value independent of wave steepness. Free roll decay results show the addition of bilge keels to a ship model increases roll period and roll damping. Results show non-linear roll decay for Fr ≤ 0.138, a transition region for 0.190 ≤ Fr ≤ 0.340, and linear roll decay for Fr ≥ 0.410 for both without and with bilge keels. Phase-averaged flow-field velocity results show the evolution and subsequent decay of the bilge keel vortex. The vortex trails the motion of the bilge keel rotating clockwise for counter-clockwise model rotation (rolling to port) and rotates counter-clockwise for clockwise model rotation (rolling to starboard). The phase-averaged wave-field resembles the steady wave pattern (Kelvin wave pattern) with a superimposed oscillation due to the rolling motion of the model. As the model rolls, alternating crests and troughs radiate from the hull

  12. Computerized Placement Management Software (CPMS): User Manual, Version 3.0.

    ERIC Educational Resources Information Center

    College Entrance Examination Board, Princeton, NJ.

    This guide is designed to enable the beginner, as well as the advanced user, to understand and use the Computerized Placement Management Software (CPMS). The CPMS is a system for evaluating information about students and recommending their placement into courses best suited for them. It also tracks their progress and maintains their records. The…

  13. Validating the Use of AP® Exam Scores for College Course Placement. Research Report 2013-2

    ERIC Educational Resources Information Center

    Patterson, Brian F.; Ewing, Maureen

    2013-01-01

    The Advanced Placement Program® (AP®) was created to provide access to rigorous, college-level curricula to motivated and prepared high school students. This study evaluated whether the AP Exam scores from the summative exams associated with 10 courses were valid for the placement of students into higher-level college courses in the subject area…

  14. Job Placement Regimes in Europe: Trends and Impacts of Changes. IAB Labour Market Research Topics.

    ERIC Educational Resources Information Center

    Konle-Seidl, Regina; Walwei, Ulrich

    Trends in job placement in Europe and the effects of advances in information and communication technologies on job placement practices were examined through case studies of France, Germany, the Netherlands, and the United Kingdom. The case studies revealed that the market shares of public employment services (PES) are generally higher than those…

  15. Tu-144LL SST Flying Laboratory Being Towed Down Taxiway

    NASA Technical Reports Server (NTRS)

    1998-01-01

    With its giant delta wings drooping toward the ground, the Tupolev Tu-144LL is towed down a taxiway at the Zhukovsky Air Development Center near Moscow, Russia, in preparation for a high-speed research flight in 1998. NASA teamed with American and Russian aerospace industries for an extended period in a joint international research program featuring the Russian-built Tu-144LL supersonic aircraft. The object of the program was to develop technologies for a proposed future second-generation supersonic airliner to be developed in the 21st Century. The aircraft's initial flight phase began in June 1996 and concluded in February 1998 after 19 research flights. A shorter follow-on program involving seven flights began in September 1998 and concluded in April 1999. All flights were conducted in Russia from Tupolev's facility at the Zhukovsky Air Development Center near Moscow. The centerpiece of the research program was the Tu 144LL, a first-generation Russian supersonic jetliner that was modified by its developer/builder, Tupolev ANTK (aviatsionnyy nauchno-tekhnicheskiy kompleks-roughly, aviation technical complex), into a flying laboratory for supersonic research. Using the Tu-144LL to conduct flight research experiments, researchers compared full-scale supersonic aircraft flight data with results from models in wind tunnels, computer-aided techniques, and other flight tests. The experiments provided unique aerodynamic, structures, acoustics, and operating environment data on supersonic passenger aircraft. Data collected from the research program was being used to develop the technology base for a proposed future American-built supersonic jetliner. Although actual development of such an advanced supersonic transport (SST) is currently on hold, commercial aviation experts estimate that a market for up to 500 such aircraft could develop by the third decade of the 21st Century. The Tu-144LL used in the NASA-sponsored research program was a 'D' model with different engines

  16. SR-71 being towed to hangar with LASRE pod installed

    NASA Technical Reports Server (NTRS)

    1997-01-01

    NASA's SR-71 is being towed to its hangar with the Linear Aerospike SR-71 Experiment installed. The experiment was mounted on the SR-71 on Aug. 26, at the NASA Dryden Flight Research Center, Edwards, California, in preparation for its first flight. The LASRE experiment was designed to provide in-flight data to help Lockheed Martin evaluate the aerodynamic characteristics and the handling of the SR-71 linear aerospike experiment configuration. The goal of the project was to provide in-flight data to help Lockheed Martin validate the computational predictive tools it was using to determine the aerodynamic performance of a future reusable launch vehicle. The joint NASA, Rocketdyne (now part of Boeing), and Lockheed Martin Linear Aerospike SR-71 Experiment (LASRE) completed seven initial research flights at Dryden Flight Research Center. Two initial flights were used to determine the aerodynamic characteristics of the LASRE apparatus (pod) on the back of the SR-71. Five later flights focused on the experiment itself. Two were used to cycle gaseous helium and liquid nitrogen through the experiment to check its plumbing system for leaks and to test engine operational characteristics. During the other three flights, liquid oxygen was cycled through the engine. Two engine hot-firings were also completed on the ground. A final hot-fire test flight was canceled because of liquid oxygen leaks in the test apparatus. The LASRE experiment itself was a 20-percent-scale, half-span model of a lifting body shape (X-33) without the fins. It was rotated 90 degrees and equipped with eight thrust cells of an aerospike engine and was mounted on a housing known as the 'canoe,' which contained the gaseous hydrogen, helium, and instrumentation gear. The model, engine, and canoe together were called a 'pod.' The experiment focused on determining how a reusable launch vehicle's engine flume would affect the aerodynamics of its lifting-body shape at specific altitudes and speeds. The

  17. Kernel-Based Discriminant Techniques for Educational Placement

    ERIC Educational Resources Information Center

    Lin, Miao-hsiang; Huang, Su-yun; Chang, Yuan-chin

    2004-01-01

    This article considers the problem of educational placement. Several discriminant techniques are applied to a data set from a survey project of science ability. A profile vector for each student consists of five science-educational indicators. The students are intended to be placed into three reference groups: advanced, regular, and remedial.…

  18. Training Special Educators: Sustaining Professional Development in Special School Placements

    ERIC Educational Resources Information Center

    Peter, Melanie

    2013-01-01

    With the rapidly changing demographic due to survival rates from medical advances, the need to strengthen training on SEND is now recognised, and special school placements valued, having been previously marginalised within initial teacher training. Practices developed since 2008 at one university to support progression of trainees to gain advanced…

  19. Automated fiber placement composite manufacturing: The mission at MSFC's Productivity Enhancement Complex

    NASA Technical Reports Server (NTRS)

    Vickers, John H.; Pelham, Larry I.

    1993-01-01

    Automated fiber placement is a manufacturing process used for producing complex composite structures. It is a notable leap to the state-of-the-art in technology for automated composite manufacturing. The fiber placement capability was established at the Marshall Space Flight Center's (MSFC) Productivity Enhancement Complex in 1992 in collaboration with Thiokol Corporation to provide materials and processes research and development, and to fabricate components for many of the Center's Programs. The Fiber Placement System (FPX) was developed as a distinct solution to problems inherent to other automated composite manufacturing systems. This equipment provides unique capabilities to build composite parts in complex 3-D shapes with concave and other asymmetrical configurations. Components with complex geometries and localized reinforcements usually require labor intensive efforts resulting in expensive, less reproducible components; the fiber placement system has the features necessary to overcome these conditions. The mechanical systems of the equipment have the motion characteristics of a filament winder and the fiber lay-up attributes of a tape laying machine, with the additional capabilities of differential tow payout speeds, compaction and cut-restart to selectively place the correct number of fibers where the design dictates. This capability will produce a repeatable process resulting in lower cost and improved quality and reliability.

  20. Engineered Polymer Composites Through Electrospun Nanofiber Coating of Fiber Tows

    NASA Technical Reports Server (NTRS)

    Kohlman, Lee W.; Bakis, Charles; Williams, Tiffany S.; Johnston, James C.; Kuczmarski, Maria A.; Roberts, Gary D.

    2014-01-01

    Composite materials offer significant weight savings in many aerospace applications. The toughness of the interface of fibers crossing at different angles often determines failure of composite components. A method for toughening the interface in fabric and filament wound components using directly electrospun thermoplastic nanofiber on carbon fiber tow is presented. The method was first demonstrated with limited trials, and then was scaled up to a continuous lab scale process. Filament wound tubes were fabricated and tested using unmodified baseline towpreg material and nanofiber coated towpreg.

  1. 49 CFR 393.71 - Coupling devices and towing methods, driveaway-towaway operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... means of transmitting forces between the vehicles shall not be used to tow a motor vehicle weighing more... means of a saddle-mount shall have the motion of the front wheels restrained if under any condition of... constructed as to freely permit motion in both horizontal and vertical planes between the towed and...

  2. 49 CFR 393.71 - Coupling devices and towing methods, driveaway-towaway operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... bumpers as a means of transmitting forces between the vehicles shall not be used to tow a motor vehicle... towed by means of a saddle-mount shall have the motion of the front wheels restrained if under any... shall be so constructed as to freely permit motion in both horizontal and vertical planes between...

  3. 46 CFR 27.203 - What are the requirements for fire detection on towing vessels?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false What are the requirements for fire detection on towing... detection on towing vessels? You must have a fire-detection system installed on your vessel to detect engine... use an existing engine-room-monitoring system (with fire-detection capability) instead of a...

  4. 46 CFR 27.203 - What are the requirements for fire detection on towing vessels?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false What are the requirements for fire detection on towing... detection on towing vessels? You must have a fire-detection system installed on your vessel to detect engine... use an existing engine-room-monitoring system (with fire-detection capability) instead of a...

  5. Influence of the vertical load exerted by the trailer on the coupling device on towing vehicle's steerability and stability

    NASA Astrophysics Data System (ADS)

    Więckowski, D.; Pusty, T.; Jędrys, P.

    2016-09-01

    The paper concerns an analysis of the steerability and stability of a motor vehicle towing a trailer during the double lane change manoeuvre. As results of experimental road tests carried out on an airfield runway, time histories of the following parameters were determined: steering angle, lateral acceleration, and drift angle of the towing vehicle, as well as angular velocity of towing vehicle yaw. The tests were performed for various states of the vertical load exerted on towing vehicle's coupling device.

  6. 34 CFR 300.327 - Educational placements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Educational placements. 300.327 Section 300.327... Educational Placements Development of Iep § 300.327 Educational placements. Consistent with § 300.501(c), each... makes decisions on the educational placement of their child. (Authority: 20 U.S.C. 1414(e))...

  7. 34 CFR 300.327 - Educational placements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Educational placements. 300.327 Section 300.327... Educational Placements Development of Iep § 300.327 Educational placements. Consistent with § 300.501(c), each... makes decisions on the educational placement of their child. (Authority: 20 U.S.C. 1414(e))...

  8. A tow concept for the space shuttle orbiter approach and landing test

    NASA Technical Reports Server (NTRS)

    Bonner, T. F., Jr.; Pride, J. D., Jr.

    1976-01-01

    The tow concept provides the means for evaluating the orbiter aerodynamic performance and handling qualities in the same configuration as expected in actual space shuttle flight operation. A Boeing 747-100 aircraft has engine-out capability to tow the orbiter to an altitude that permits a safe orbiter approach and landing. The tow concept also provides a means for conducting a comprehensive ground test program before proceeding into the actual ALT flight operations. The implementation of the tow concept requires only a minor structural modification in the nose section of the orbiter vehicle; requires minor modifications in the 747 cargo bay; and makes use of those orbiter onboard systems installed in the ALT orbiter vehicle. The 747 wake turbulence does not constitute a problem for the orbiter during take-off or climb to altitude. The impact that the tow concept would have on the cost and schedule of the space shuttle program was not evaluated in this study.

  9. 46 CFR 2.01-50 - Persons other than crew on towing, oyster, or fishing steam vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Persons other than crew on towing, oyster, or fishing steam vessels. 2.01-50 Section 2.01-50 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES... than crew on towing, oyster, or fishing steam vessels. (a) A steam vessel engaged in towing,...

  10. 46 CFR 2.01-50 - Persons other than crew on towing, oyster, or fishing steam vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Persons other than crew on towing, oyster, or fishing steam vessels. 2.01-50 Section 2.01-50 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES... than crew on towing, oyster, or fishing steam vessels. (a) A steam vessel engaged in towing,...

  11. 46 CFR 2.01-50 - Persons other than crew on towing, oyster, or fishing steam vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Persons other than crew on towing, oyster, or fishing steam vessels. 2.01-50 Section 2.01-50 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES... than crew on towing, oyster, or fishing steam vessels. (a) A steam vessel engaged in towing,...

  12. 46 CFR 2.01-50 - Persons other than crew on towing, oyster, or fishing steam vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Persons other than crew on towing, oyster, or fishing steam vessels. 2.01-50 Section 2.01-50 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES... than crew on towing, oyster, or fishing steam vessels. (a) A steam vessel engaged in towing,...

  13. 46 CFR 2.01-50 - Persons other than crew on towing, oyster, or fishing steam vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Persons other than crew on towing, oyster, or fishing steam vessels. 2.01-50 Section 2.01-50 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES... than crew on towing, oyster, or fishing steam vessels. (a) A steam vessel engaged in towing,...

  14. 46 CFR 27.211 - What are the specifications for fuel systems on towing vessels whose construction was contracted...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... uses bunker C, heavy fuel oil (HFO), or any fuel that requires pre-heating, must comply with subchapter... 46 Shipping 1 2010-10-01 2010-10-01 false What are the specifications for fuel systems on towing... for Towing Vessels § 27.211 What are the specifications for fuel systems on towing vessels...

  15. 46 CFR 27.211 - What are the specifications for fuel systems on towing vessels whose construction was contracted...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... uses bunker C, heavy fuel oil (HFO), or any fuel that requires pre-heating, must comply with subchapter... 46 Shipping 1 2013-10-01 2013-10-01 false What are the specifications for fuel systems on towing... for Towing Vessels § 27.211 What are the specifications for fuel systems on towing vessels...

  16. 46 CFR 27.211 - What are the specifications for fuel systems on towing vessels whose construction was contracted...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... uses bunker C, heavy fuel oil (HFO), or any fuel that requires pre-heating, must comply with subchapter... 46 Shipping 1 2014-10-01 2014-10-01 false What are the specifications for fuel systems on towing... for Towing Vessels § 27.211 What are the specifications for fuel systems on towing vessels...

  17. Manufacturing of Smart Structures Using Fiber Placement Manufacturing Processes

    NASA Technical Reports Server (NTRS)

    Thomas, Matthew M.; Glowasky, Robert A.; McIlroy, Bruce E.; Story, Todd A.

    1996-01-01

    Smart structures research and development, with the ultimate aim of rapid commercial and military production of these structures, are at the forefront of the Synthesis and Processing of Intelligent Cost-Effective Structures (SPICES) program. As part of this ARPA-sponsored program, MDA-E is using fiber placement processes to manufacture integrated smart structure systems. These systems comprise advanced composite structures with embedded fiber optic sensors, shape memory alloys, piezoelectric actuators, and miniature accelerometers. Cost-effective approaches and solutions to smart material synthesis in the fiber-placement process, based upon integrated product development, are discussed herein.

  18. An experimental investigation of the equilibrium and stability of long towed cable systems

    NASA Astrophysics Data System (ADS)

    Obligado, Martin; Bourgoin, Mickaël

    2013-04-01

    The dynamics of towed objects in a fluid environment is of interest for many practical situations. We investigate experimentally the equilibrium and stability of the trajectory of a sphere towed at constant velocity at the tip of a cable with an unprecedented large length-to-diameter aspect ratio, exceeding 104. The towing configuration is artificially obtained by considering a steady cable (with one fixed end and a free end to which a sphere is eventually attached) in a low-turbulence wind tunnel. We consider three different configurations: (i) the cable towed by itself; (ii) a light millimetric towed sphere made of expanded polystyrene; and (iii) a denser millimetric towed sphere made of lead. The trajectory of the cable tip is monitored using high-speed Lagrangian tracking, which allows one to characterize the average position and the dynamical fluctuations of the towed object. We show that the mean equilibrium position is well predicted by a simple model including the aerodynamical forces acting along the cable and on the towed sphere (when present). Concerning stability issues, we find that the heavy lead particle is always towed in stable conditions (within the accessible range of velocities) with only very low energy oscillations related to a weak pendulum-like motion. In contrast, the free end and light sphere cases are shown to become unstable when the towing velocity exceeds a certain threshold. Spectral analysis shows a flutter-type instability for the sphere, with a dominant oscillatory motion, while the cable alone develops a divergence-type instability with random fluctuations.

  19. F-106 tow cable attachment and release mechanism for Eclipse program

    NASA Technical Reports Server (NTRS)

    1997-01-01

    View of the tow cable attachment and release mechanism forward of the cockpit on the QF-106 Eclipse aircraft. This mechanism held and then released the Vectran rope used to tow the QF-106 behind an Air Force C-141A. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  20. M2-F1 in flight on tow line

    NASA Technical Reports Server (NTRS)

    1964-01-01

    The M2-F1 Lifting Body is seen here under tow at the Flight Research Center (later redesignated the Dryden Flight Research Center), Edwards, California. The wingless, lifting-body aircraft design was initially concieved as a means of landing an aircraft horizontally after atmospheric reentry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Flight Research Center management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a 'flying bathtub,' and was designated the M2-F1, the 'M' referring to 'manned' and 'F' referring to 'flight' version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The M2-F1 project had limited goals. They were to show that a piloted lifting body could be built, that it could not only fly but be controlled in flight, and that it could make a successful landing. While the M2-F1 did prove the concept, with a wooden fuselage and fixed landing gear, it was far from an operational spacecraft. The next step in the lifting-body development was to build a heavyweight, rocket-powered vehicle that was more like an operational lifting body, albeit one without the thermal protection system that would be needed for reentry into the atmosphere from space at near-orbital speeds. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds up to about 120 mph. These initial tests produced enough flight data about the M2-F1 to proceed with flights behind a NASA C-47 tow plane at greater altitudes. The C-47 took the craft to an altitude of 12,000 where free flights back to Rogers Dry Lake began. Pilot for the first series of flights of the M2-F1 was NASA research pilot Milt Thompson. Typical glide flights with the M2-F1 lasted about two minutes and reached speeds of 110 to

  1. Sensor placement optimization in buildings

    NASA Astrophysics Data System (ADS)

    Bianco, Simone; Tisato, Francesco

    2012-01-01

    In this work we address the problem of optimal sensor placement for a given region and task. An important issue in designing sensor arrays is the appropriate placement of the sensors such that they achieve a predefined goal. There are many problems that could be considered in the placement of multiple sensors. In this work we focus on the four problems identified by Hörster and Lienhart. To solve these problems, we propose an algorithm based on Direct Search, which is able to approach the global optimal solution within reasonable time and memory consumption. The algorithm is experimentally evaluated and the results are presented on two real floorplans. The experimental results show that our DS algorithm is able to improve the results given by the most performing heuristic introduced in. The algorithm is then extended to work also on continuous solution spaces, and 3D problems.

  2. Eclipse project closeup of QF-106 under tow on takeoff on first flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    OFF THE GROUND - The Kelly Space & Technology (KST)/USAF/NASA Eclipse project's modified QF-106 lifts off under tow on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, hosted the project, providing engineering and facility support as well as the project pilot. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  3. Eclipse project closeup of QF-106 under tow on first tethered flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Kelly Space and Technology (KST)/USAF/NASA Eclipse project's modified QF-106 is shown under tow on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, is hosting the project, providing engineering and facility support as well as the project pilot, Mark Stucky. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  4. Horizontal ichthyoplankton tow-net system with unobstructed net opening

    USGS Publications Warehouse

    Nester, Robert T.

    1987-01-01

    The larval fish sampler described here consists of a modified bridle, frame, and net system with an obstruction-free net opening and is small enough for use on boats 10 m or less in length. The tow net features a square net frame attached to a 0.5-m-diameter cylinder-on-cone plankton net with a bridle designed to eliminate all obstructions forward of the net opening, significantly reducing currents and vibrations in the water directly preceding the net. This system was effective in collecting larvae representing more than 25 species of fish at sampling depths ranging from surface to 10 m and could easily be used at greater depths.

  5. Surface towed electromagnetic system for mapping of subsea Arctic permafrost

    NASA Astrophysics Data System (ADS)

    Sherman, Dallas; Kannberg, Peter; Constable, Steven

    2017-02-01

    Sea level has risen globally since the late Pleistocene, resulting in permafrost-bearing coastal zones in the Arctic being submerged and subjected to temperature induced degradation. Knowing the extent of permafrost and how it changes over time is important for climate change predictions and for planning engineering activities in the Arctic environment. We developed a controlled source electromagnetic (CSEM) method to obtain information on the depth, thickness, and lateral extent of marine permafrost. To operate in shallow water we used a surface towed electric dipole-dipole CSEM system suitable for deployment from small boats. This system was used to map permafrost on the Arctic shelf offshore Prudhoe Bay, Alaska. Our results show significant lateral variability in the presence of permafrost, with the thickest layers associated with a large river outflow where freshwater influx seems to have a preserving effect on relict subsea permafrost.

  6. The Placement Professional as Marketeer.

    ERIC Educational Resources Information Center

    Walz, Garry R.

    1988-01-01

    Discusses resistance of helping professions to marketing. Defines human services marketing. Describes forces that are placing human services in an increasingly competitive position. Makes recommendations to enhance the image of career planning and placement services and increase their usage. Concludes that by adopting a marketeer orientation,…

  7. Placement Services: A Training Manual.

    ERIC Educational Resources Information Center

    National Advisory Council on Vocational Education, Washington, DC.

    This self-contained instructional package defines a comprehensive job placement program as a coordinated series of activities involving school-community interaction, staff training and curriculum development resulting in youth being able to obtain and retain satisfying employment. The author and contributors focus their efforts on presenting case…

  8. A Consideration of Placement Testing.

    ERIC Educational Resources Information Center

    Kilpatrick, Gordon

    This report consists of three sections, the first of which is a discussion of placement testing. It is maintained that the strengths and weaknesses of a tested population cannot be determined by a single composite test--yet, many institutions place students in beginning courses on the basis of such limited information. To assess basic capabilities…

  9. The Ironies of Mandatory Placement.

    ERIC Educational Resources Information Center

    Hadden, Craig

    2000-01-01

    Suggests that mandatory placement of underprepared students in developmental courses may actually provide the key to opening the door to true academic, vocational, or community success, despite criticism by some that it excludes students and restricts their freedoms. Discusses ethical balances between access, student success and academic…

  10. College Student Personnel Graduate Placement

    ERIC Educational Resources Information Center

    Packwood, William

    1976-01-01

    ACPA's Commission XII surveyed 103 college student personnel training institutions regarding their graduate placement. Graduates were identified according to degree, sex, and race. Percentages of graduates placed, areas within the college student personnel field, types of institutions, and areas of the country were computed. The discussion…

  11. 33 CFR 164.74 - Towline and terminal gear for towing astern.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... intended service; (iii) Appropriate for the sea conditions expected during the intended service; (iv... abrasion or chafing by chafing gear, lagging, or other means; (6) Except on board a vessel towing in ice...

  12. 33 CFR 164.74 - Towline and terminal gear for towing astern.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... intended service; (iii) Appropriate for the sea conditions expected during the intended service; (iv... abrasion or chafing by chafing gear, lagging, or other means; (6) Except on board a vessel towing in ice...

  13. Lumbar Catheter Placement Using Paramedian Approach Under Fluoroscopic Guidance

    PubMed Central

    Qureshi, Adnan I.; Khan, Asif A.; Malik, Ahmed A.; Afzal, Mohammad Rauf; Herial, Nabeel A.; Qureshi, Mushtaq H.; Suri, M. Fareed K.

    2016-01-01

    Background Lumbar catheter placement under fluoroscopic guidance may reduce the rate of technical failures and associated complications seen with insertion guided by manually palpable landmarks. Methods We reviewed our experience with 43 attempted lumbar catheter placements using paramedian approach under fluoroscopic guidance and ascertained rates of technical success, and clinical events. Results Among the 43 patients, 18, 1, and 1 patients were on aspirin (with dipyrimadole in 2), clopidogrel, and combination of both, respectively. Lumbar catheter placement was successful in 42 of 43 attempted placements. Floroscopic guidance was critical in three patients; one patient had severe cerebrospinal fluid (CSF) depletion (empty thecal sac phenomenon) following pituitary surgery leading to no cerebrospinal fluid return despite correct placement confirmation under fluoroscopy. Two patients had spinal needle placement at the junction between epidural and cerebrospinal fluid spaces (junctional position) leading to cerebrospinal fluid return but inability to introduce the lumbar catheter. After confirmation of position by the injection of contrast or radiographic landmarks the needle was advanced by indenting the subcutaneous tissue or reinserting at a spinal level above the first insertion. The lumbar catheter remained in position over a mean period (±standard deviation) of 4.1(±2.3) days. Improvement in hydrocephalus was seen in two patients with intracranial mass lesions. One patient developed cerebrospinal fluid leakage through the insertion track following removal of catheter and required skin suturing at the site of insertion. Conclusions We observed a high technical success rate with low rate of complications even in patients with intracranial mass lesions, those on ongoing antiplatelet medications or in whom insertion would not be possible guided by manually palpable landmarks. PMID:26958156

  14. Evaluation of the Impact of Towing the L-1011 Airplane at Boston-Logan Airport

    DTIC Science & Technology

    1980-05-01

    Stress analysis of the nose landing gear and back-up structure was performed using the load spectrum representing extended towing at Boston-Logan. The...Dorval testing) T. Blase (Stress analysis ) The Lockheed effort was supervised by J.E. Wignot (Dynamics and Vibration Group) under the management of A.F...design fatigue load spectrum was used as a basepoint for the analysis , with the original towing load spectrum replaced by the spectrum representing

  15. Driven microswimmers on a 2D substrate: A stochastic towed sled model

    SciTech Connect

    Marchegiani, Giampiero; Marchesoni, Fabio

    2015-11-14

    We investigate, both numerically and analytically, the diffusion properties of a stochastic sled sliding on a substrate, subject to a constant towing force. The problem is motivated by the growing interest in controlling transport of artificial microswimmers in 2D geometries at low Reynolds numbers. We simulated both symmetric and asymmetric towed sleds. Remarkable properties of their mobilities and diffusion constants include sidewise drifts and excess diffusion peaks. We interpret our numerical findings by making use of stochastic approximation techniques.

  16. Towing of sensory axons by their migrating target cells in vivo.

    PubMed

    Gilmour, Darren; Knaut, Holger; Maischein, Hans-Martin; Nüsslein-Volhard, Christiane

    2004-05-01

    Many pathfinding axons must locate target fields that are themselves positioned by active migration. A hypothetical method for ensuring that these migrations are coordinated is towing, whereby the extension of axons is entirely dependent on the migration of their target cells. Here we combine genetics and time-lapse imaging in the zebrafish to show that towing by migrating cells is a bona fide mechanism for guiding pathfinding axons in vivo.

  17. Dynamic Towed Array Models and State Estimation for Underwater Target Tracking

    DTIC Science & Technology

    2013-09-01

    19, 2013. [6] S. G. Lemon , “Towed-array history, 1917–2003,” IEEE J. of Ocean. Eng., vol. 29, pp. 365–373, Apr. 2004. [7] M. S. Cohen and R. V...and S. G. Lemon , “Recent progress in towed hydrophone array research,” IEEE J. of Ocean. Eng., vol. 29, pp. 374–387, Apr. 2004. [10] B. L. Scala

  18. Mathematics Placement at the University of Illinois

    ERIC Educational Resources Information Center

    Ahlgren Reddy, Alison; Harper, Marc

    2013-01-01

    Data from the ALEKS-based placement program at the University of Illinois is presented visually in several ways. The placement exam (an ALEKS assessment) contains precise item-specific information and the data show many interesting properties of the student populations of the placement courses, which include Precalculus, Calculus, and Business…

  19. Can Placement Tests Inform Instructional Decisions?

    ERIC Educational Resources Information Center

    Green, Anthony B.; Weir, Cyril J.

    2004-01-01

    Studies of placement tests are typically narrowly concerned with their validation as instruments for the efficient grouping of students. They rarely explore the assumption that placement test content can be related to classroom tasks and so inform instructional decisions. This study focuses on a trial version of the Global Placement Test (GPT), a…

  20. 28 CFR 551.24 - Child placement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Child placement. 551.24 Section 551.24 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Birth Control, Pregnancy, Child Placement, and Abortion § 551.24 Child placement. (a) The Warden may...

  1. 28 CFR 551.24 - Child placement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Child placement. 551.24 Section 551.24 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Birth Control, Pregnancy, Child Placement, and Abortion § 551.24 Child placement. (a) The Warden may...

  2. 28 CFR 551.24 - Child placement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Child placement. 551.24 Section 551.24 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Birth Control, Pregnancy, Child Placement, and Abortion § 551.24 Child placement. (a) The Warden may...

  3. 28 CFR 551.24 - Child placement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Child placement. 551.24 Section 551.24 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Birth Control, Pregnancy, Child Placement, and Abortion § 551.24 Child placement. (a) The Warden may...

  4. 28 CFR 551.24 - Child placement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Child placement. 551.24 Section 551.24 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Birth Control, Pregnancy, Child Placement, and Abortion § 551.24 Child placement. (a) The Warden may...

  5. 5 CFR 359.702 - Placement rights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Placement rights. 359.702 Section 359.702 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REMOVAL FROM THE SENIOR EXECUTIVE SERVICE; GUARANTEED PLACEMENT IN OTHER PERSONNEL SYSTEMS Guaranteed Placement § 359.702...

  6. 5 CFR 359.702 - Placement rights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Placement rights. 359.702 Section 359.702 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REMOVAL FROM THE SENIOR EXECUTIVE SERVICE; GUARANTEED PLACEMENT IN OTHER PERSONNEL SYSTEMS Guaranteed Placement § 359.702...

  7. Role of Mechanics of Textile Preform Composites in the NASA Advanced Composites Technology Program

    SciTech Connect

    Harris, C.E.; Poe, C.C. Jr.

    1995-10-01

    The Advanced Composites Technology Program was initiated by NASA as a partnership with the United States aeronautical industry in fiscal year 1989. The broad objective of the Program was to develop the technology to design and manufacture cost-effective and structurally optimized light-weight composite airframe primary structure. Phase A of the Program, 1989-1991, focused on the identification and evaluation of innovative manufacturing technologies and structural concepts. At the end of Phase A, the leading wing and fuselage design concepts were down-selected for further development in Phase B of the Program, 1992-1995. Three major fabrication technologies emerged from Phase A. These three approaches were the stitched dry preform, textile preform, and automated tow placement manufacturing methods. Each method emphasized rapid fiber placement, near net-shape preform fabrication, part count minimization, and matching the technologies to the specific structural configurations and requirements. The objective of Phase B was to continue the evolution of design concepts using the concurrent engineering process, down-select to the leading structural concept, and design, build, and test subscale components. Phase C of the ACT Program, 1995-2002, is a critical element of the NASA Advanced Subsonic Technology Program and has been approved for implementation beginning in 1995. The objective of Phase C is to design, build, and test major components of the airframe to demonstrate the technology readiness for applications in the next generation subsonic commercial transport aircraft. Part of the technology readiness demonstration will include a realistic comparison of manufacturing costs and an increased confidence in the ability to accurately estimate the costs of composite structure. The Program Plan calls for the structural components to be a complete fuselage barrel with a window-belt and a wing box at the wing/fuselage intersection.

  8. The link between middle school mathematics course placement and achievement.

    PubMed

    Domina, Thurston

    2014-01-01

    The proportion of eighth graders in United States public schools enrolled in algebra or a more advanced mathematics course doubled between 1990 and 2011. This article uses Early Childhood Longitudinal Study's Kindergarten Cohort data to consider the selection process into advanced middle school mathematics courses and estimate the effects of advanced courses on students' mathematics achievement (n = 6,425; mean age at eighth grade = 13.7). Eighth-grade algebra and geometry course placements are academically selective, but considerable between-school variation exists in students' odds of taking these advanced courses. While analyses indicate that advanced middle school mathematics courses boost student achievement, these effects are most pronounced in content areas closely related to class content and may be contingent on student academic readiness.

  9. Humanitarian engineering placements in our own communities

    NASA Astrophysics Data System (ADS)

    VanderSteen, J. D. J.; Hall, K. R.; Baillie, C. A.

    2010-05-01

    There is an increasing interest in the humanitarian engineering curriculum, and a service-learning placement could be an important component of such a curriculum. International placements offer some important pedagogical advantages, but also have some practical and ethical limitations. Local community-based placements have the potential to be transformative for both the student and the community, although this potential is not always seen. In order to investigate the role of local placements, qualitative research interviews were conducted. Thirty-two semi-structured research interviews were conducted and analysed, resulting in a distinct outcome space. It is concluded that local humanitarian engineering placements greatly complement international placements and are strongly recommended if international placements are conducted. More importantly it is seen that we are better suited to address the marginalised in our own community, although it is often easier to see the needs of an outside populace.

  10. Eigenvalues of the sample covariance matrix for a towed array.

    PubMed

    Gerstoft, Peter; Menon, Ravishankar; Hodgkiss, William S; Mecklenbräuker, Christoph F

    2012-10-01

    It is well known that observations of the spatial sample covariance matrix (SCM, also called the cross-spectral matrix) reveal that the ordered noise eigenvalues of the SCM decay steadily, but common models predict equal noise eigenvalues. Random matrix theory (RMT) is used to derive and discuss properties of the eigenvalue spectrum of the data SCM for linear arrays, with an application to ocean acoustic data. Noise on the array is considered either incoherent or propagating acoustic noise that is coherent across the array. Using conventional three-dimensional or two-dimensional isotropic noise models with full or snapshot-deficient observations, realizations of the SCM eigenvalues are explained using RMT. Deep-water towed-array data are analyzed and it is shown that the eigenvalues of the SCM compare well with theory. It is demonstrated how RMT can be applied to study eigenvalue spectrum estimation as dependent on array properties (element spacing to wavelength ratio) and data sampling (snapshots). Apart from explaining the observed noise eigenvalue spectrum, the improved model of the eigenvalue spectrum has important applications in array signal processing.

  11. Full Scale Wind Tunnel and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Construction progress, Full Scale exit cone looking south from entrance cone, east switchboard, west switchboard, wind vanes at north end looking north through entrance cone, north end looking south through entrance cone, entrance cone looking north from exit cone, wind vanes south end of west exit cone, wind vanes south end of east exit cone, Tow Channel trolley lines looking north, east and west incline braces at north end. Full-Scale Tunnel (FST) exit cone construction and installation of fan motors. Smith DeFrance describes the entrance cone in NACA TR 459 as follows: 'Forward of the propellers and located on the center line of the tunnel is a smooth fairing which transforms the somewhat elliptic section of the single passage into two circular ones at the propellers. From the propellers aft, the exit cone is divided into two passages and each transforms in the length of 132 feet from a 35-foot 61/2-inch circular section to a 46-foot square. The included angle between the sides of each passage is 6 inches.' (p. 293)

  12. COURSE OUTLINE AND TEACHING GUIDE FOR ADVANCED STANDING ENGLISH II.

    ERIC Educational Resources Information Center

    THOMPSON, PHILLIP

    THE ADVANCED STANDING PROGRAM IN ENGLISH IS DESIGNED TO PREPARE SELECTED STUDENTS FOR THE ADVANCED PLACEMENT CLASSES, WHICH ARE EQUIVALENT OF COLLEGE FRESHMAN ENGLISH, IN HIGH SCHOOL. WHILE KEEPING ADVANCED PLACEMENT NEEDS IN MIND, EMPHASIS IN CURRICULUM IS PLACED ON THE MORE IMPORTANT GOAL OF BETTER COLLEGE PREPARATION IN ENGLISH. THE ADVANCED…

  13. A Tow-Level Progressive Damage for Simulating Carbon-Fiber Textile Composites: Interim Report

    SciTech Connect

    Zywicz, E.

    2000-07-01

    A numerical approach to model the elasto-plastic and tensile damage response of tri-axially braided carbon-fiber polymeric-matrix composites is developed. It is micromechanically based and consists of a simplified unit cell geometry, a plane-stress tow-level constitutive relationship, a one-dimensional undulation constitutive law, and a non-traditional shell element integration rule. The braided composite lamina is idealized as periodic in the plane, and a simplified three-layer representative volume (RV) is assembled from axial and braider tows and pure resin regions. The constituents in each layer are homogenized with an iso-strain assumption in the fiber-direction and an iso-stress condition in the other directions. In the upper and lower layers, the fiber-direction strain is additively decomposed into an undulation and a tow portion. A finite-deformation tow model predicts the plane-stress tow response and is coupled to the undulation constitutive relationship. The overall braid model is implemented in DYNA3D and works with traditional shell elements. The finite-deformation tow constitutive relationship is derived from the fiber elasticity and the isotropic elasto-plastic power-law hardening matrix response using a thermodynamic framework and simple homogenization assumptions. The model replicates tensile damage evolution, in a smeared sense, parallel and perpendicular to the fiber axis and is regularized to yield mesh independent results. The tow-level model demonstrates reasonable agreement, prior to damage, with detailed three-dimensional FE (finite element) elasto-plastic simulations of aligned, periodically arranged, uni-directional composites. The 3-layer braid model response is compared with predictions obtained from detailed micromechanical simulations of the braid's unit cell in uni-axial extension, shear, and flexure for three braid angles. The elastic properties show good agreement as does the non-linear response for loadings dominated by the axial

  14. A Model for Tow Impregnation and Consolidation for Partially Impregnated Thermoset Prepregs

    SciTech Connect

    John J. Gangloff Jr; Shatil Sinha; Suresh G. Advani

    2011-05-23

    The formation and transport of voids in composite materials remains a key research area in composite manufacturing science. Knowledge of how voids, resin, and fiber reinforcement propagate throughout a composite material continuum from green state to cured state during an automated tape layup process is key to minimizing defects induced by void-initiated stress concentrations under applied loads for a wide variety of composite applications. This paper focuses on modeling resin flow in a deforming fiber tow during an automated process of partially impregnated thermoset prepreg composite material tapes. In this work, a tow unit cell based model has been presented that determines the consolidation and impregnation of a thermoset prepreg tape under an input pressure profile. A parametric study has been performed to characterize the behavior of varying tow speed and compaction forces on the degree of consolidation. Results indicate that increased tow consolidation is achieved with slower tow speeds and higher compaction forces although the relationship is not linear. The overall modeling of this project is motivated to address optimization of the 'green state' composite properties and processing parameters to reduce or eliminate 'cured state' defects, such as porosity and de-lamination. This work is partially funded by the Department of Energy under Award number DE-EE0001367.

  15. A continuously towed vertical bipole source for marine magnetometric resistivity surveying

    NASA Astrophysics Data System (ADS)

    Seama, Nobukazu; Tada, Noriko; Goto, Tada-nori; Shimoizumi, Masashi

    2013-08-01

    We propose to use an approximately vertical bipole electric current towed by a ship as a source for a Magnetometric Resistivity (MMR) method. This proposal requires the precise positioning of the bottom electrode for the bipole source, and our newly developed MMR system achieved this. We conducted an MMR experiment in the central Mariana Trough, and we obtained data using two different methods along a survey line: one method towed a bipole source transmitting continuously along the survey line, and the other used a conventional vertical bipole source transmitting at several stationary transmission stations along the survey line. We found that the towed bipole source tilted from the vertical by an angle of 8 degrees at the maximum during the MMR experiment. We compared the results from the two methods to evaluate the towed bipole source method. Our results indicate that the tilted bipole source approximates well with the vertical bipole source at the mid-point between the surface and the bottom electrodes. Since the towed bipole source method requires much less survey time and the results show a higher spatial resolution, it is a powerful tool for MMR experiments to image a shallow oceanic crustal resistivity structure efficiently.

  16. Anisotropic 3D inversion of towed streamer EM data from the Troll West oil province (Invited)

    NASA Astrophysics Data System (ADS)

    Mattsson, J.; Midgley, J.; Zhdanov, M. S.; ENDO, M.

    2013-12-01

    Obviating the need for ocean bottom receivers, the towed streamer EM system enables CSEM data to be acquired simultaneously with seismic over very large areas in frontier and mature basins for higher production rates and more cost effective than conventional marine CSEM. The towed streamer EM data are currently processed and delivered as a spectrum of frequency-domain responses. We apply a 3D anisotropic inversion methodology for towed streamer EM data that includes a moving sensitivity domain. Our implementation is based on the 3D contraction integral equation method for computing the EM responses and Fréchet derivatives, and uses the re-weighted regularized conjugate gradient method for minimizing the objective functional with focusing regularization. We present an actual case study for the 3D anisotropic inversion of towed streamer EM data from the Troll West oil province in the North Sea, and demonstrate our ability to image the Troll West Oil and Gas Provinces. We conclude that 3D anisotropic inversion of the data from the current generation of towed streamer EM system can adequately recover both the vertical and horizontal resistivities in anisotropic hydrocarbon-bearing formations.

  17. Acadian flycatcher nest placement: Does placement influence reproductive success?

    USGS Publications Warehouse

    Wilson, R.R.; Cooper, R.J.

    1998-01-01

    We located 511 Acadian Flycatcher (Empidonax virescens) nests in bottomland hardwood forest of eastern Arkansas. Microhabitat characteristics were measured and their relationship with nest success evaluated. Fifty-two percent of all nesting attempts resulted in predation. Attributes of nest placement were similar between successful and unsuccessful nests, although successful nests were placed higher. Similarly, nonparasitized nests were typically higher than parasitized nests. Nests initiated late in the breeding season were placed in larger trees with higher canopy bases resulting in increased vegetation around the nest. Fifteen different tree species were used for nesting. Acadian Flycatchers chose nest trees in a nonrandom fashion, selecting Nuttall oak (Quercus nuttallii) and possumhaw (Ilex decidua) in greater proportions than their availability. However, there was no relationship between tree species used for nesting and nest success. Nest height was positively correlated with concealment at the nest site, supporting the predator-avoidance theory. No other attribute of nest placement differentiated successful nest sites, suggesting that nest predation is likely a function of random events in space and time.

  18. Full Scale Tunnel (FST) and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Aerial and ground views of the overall construction of Full-Scale Tunnel (FST) and the Seaplane Tow Channel. In November 1929, Smith DeFrance submitted his recommendations for the general design of the Full Scale Wind Tunnel. The last on his list concerned the division of labor required to build this unusual facility. He believed the job had five parts and described them as follows: 'It is proposed that invitations be sent out for bids on five groups of items. The first would be for one contract on the complete structure; second the same as first, including the erection of the cones but not the fabrication, since this would be more of a shipyard job; third would cover structural steel, cover, sash and doors, but not cones or foundation; fourth, foundations; an fifth, fabrication of cones.' DeFrance's memorandum prompted the NACA to solicit estimates from a large number of companies. Preliminary designs and estimates were prepared and submitted to the Bureau of the Budget and Congress appropriated funds on February 20, 1929. The main construction contract with the J.A. Jones Company of Charlotte, North Carolina was signed one year later on February 12, 1930. It was a peculiar structure as the building's steel framework is visible on the outside of the building. DeFrance described this in NACA TR No. 459: 'The entire equipment is housed in a structure, the outside walls of which serve as the outer walls of the return passages. The over-all length of the tunnel is 434 feet 6 inches, the width 222 feet, and the maximum height 97 feet. The framework is of structural steel....' (pp. 292-293). Ground shots of work in progress, aerials of east area.

  19. Full Scale Wind Tunnel and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Construction progress, studding in Tow Channel office area, Full Scale motor fairing in west exit cone, motor fairing in east exit cone. Propeller and motor fairing for west exit cone. Smith DeFrance described the propellers and motors in NACA TR No. 459. ' The propellers are located side by side and 48 feet aft of the throat of the exit-cone bell. The propellers are 35 feet 5 inches in diameter and each consists of four cast aluminum alloy blades screwed into a cast steel hub.' 'The most commonly used power plant for operating a wind tunnel is a direct-current motor and motor-generator set with Ward Leonard control system. For the full-scale wind tunnel it was found that alternating current slip-ring induction motors, together with satisfactory control equipment, could be purchased for approximately 30 percent less than the direct-current equipment. Two 4,000-horsepower slip-ring induction motors with 24 steps of speed between 75 and 300 r.p.m. were therefore installed. In order to obtain the range of speed one pole change was provided and the other variations are obtained by the introduction of resistance in the rotor circuit. This control permits a variation in air speed from 25 to 118 miles per hour. The two motors are connected through an automatic switchboard to one drum-type controller located in the test chamber. All the control equipment is interlocked and connected through time-limit relays, so that regardless of how fast the controller handle is moved the motors will increase in speed at regular intervals.' (p. 294-295)

  20. Monitoring tidal currents with a towed ADCP system

    NASA Astrophysics Data System (ADS)

    Sentchev, Alexei; Yaremchuk, Max

    2016-01-01

    The tidal circulation in the semi-enclosed Boulogne harbour (eastern English Channel) is measured during the various stages of the tidal cycle with a low-cost towed Acoustic Doppler Current Profiler (ADCP) system for the first time. The system is equipped with an interpolation algorithm which allows reconstructing space-time evolution of the velocity field for surveys whose duration is comparable or larger than the typical time of tidal variation (1-2 h). The method employs space-time velocity covariances derived from a numerical simulation of the surveyed area by a high-resolution relocatable model "Model for Applications on Regional Scale" (MARS). The covariances are utilized by the optimal interpolation algorithm to obtain the most likely evolution of the velocity field under the constraints provided by the ADCP observations and their error statistics. Technically, the MARS model run provides the first guess (background) evolution of the velocity field in the surveyed area which is then corrected by the data in a statistically consistent manner as it explicitly takes into the account both observational and modeling errors. The quality of the velocity reconstruction was validated against independent bottom-mounted ADCP data, the background model evolution, and against the results of spatial interpolation by Kriging technique. All tests demonstrated significant (30 to 60 %) reduction of the model-data misfit for the velocity field obtained as a result of space-time optimal interpolation. Although the method was applied to recover surface circulation, it can be extended for assessment of the full 4D tidal flow dynamics using the data recorded throughout the entire water column.

  1. Two-dimensional optimal sensor placement

    SciTech Connect

    Zhang, H.

    1995-05-01

    A method for determining the optimal two-dimensional spatial placement of multiple sensors participating in a robot perception task is introduced in this paper. This work is motivated by the fact that sensor data fusion is an effective means of reducing uncertainties in sensor observations, and that the combined uncertainty varies with the relative placement of the sensors with respect to each other. The problem of optimal sensor placement is formulated and a solution is presented in the two dimensional space. The algebraic structure of the combined sensor uncertainty with respect to the placement of sensor is studied. A necessary condition for optimal placement is derived and this necessary condition is used to obtain an efficient closed-form solution for the global optimal placement. Numerical examples are provided to illustrate the effectiveness and efficiency of the solution. 11 refs.

  2. NASA Automated Fiber Placement Capabilities: Similar Systems, Complementary Purposes

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Jackson, Justin R.; Pelham, Larry I.; Stewart, Brian K.

    2015-01-01

    New automated fiber placement systems at the NASA Langley Research Center and NASA Marshall Space Flight Center provide state-of-art composites capabilities to these organizations. These systems support basic and applied research at Langley, complementing large-scale manufacturing and technology development at Marshall. These systems each consist of a multi-degree of freedom mobility platform including a commercial robot, a commercial tool changer mechanism, a bespoke automated fiber placement end effector, a linear track, and a rotational tool support structure. In addition, new end effectors with advanced capabilities may be either bought or developed with partners in industry and academia to extend the functionality of these systems. These systems will be used to build large and small composite parts in support of the ongoing NASA Composites for Exploration Upper Stage Project later this year.

  3. Peripheral Stent Placement in Hemodialysis Grafts

    SciTech Connect

    Kariya, Shuji Tanigawa, Noboru; Kojima, Hiroyuki; Komemushi, Atsushi; Shomura, Yuzo; Shiraishi, Tomokuni; Kawanaka, Toshiaki; Sawada, Satoshi

    2009-09-15

    The purpose of the present study was to evaluate the clinical outcome of peripheral stent placement after failed balloon angioplasty in patients with grafts who are on hemodialysis. We examined 30 Wallstents that were placed in 26 patients because balloon angioplasty failed or early restenosis (<3 months) occurred within 3 months. We retrospectively reviewed 267 consecutive balloon angioplasties performed in 71 patients with graft access between August 2000 and March 2007. Stent placements accounted for 30 (11.2%) of the 267 balloon angioplasties. The clinical success rate of stent placement was 93.3% (28 of 30 stent placements). The 3-, 6-, and 12-month primary patency rates were 73.3%, 39.3%, and 17.7%, respectively. The 1-, 2-, and 3-year secondary patency rates were 90.2%, 83.8%, and 83.8%, respectively. Primary patency was significantly prolonged by stent placement after early restenosis compared with previous balloon angioplasty alone (P = 0.0059). Primary patency after stent placement was significantly lower than after successful balloon angioplasty without indications for stent placement (P = 0.0279). Secondary patency rates did not significantly differ between stent placement and balloon angioplasty alone. The mean number of reinterventions required to maintain secondary patency after stent placement was significantly larger than that after balloon angioplasty alone (Mann-Whitney U test, P = 0.0419). We concluded that peripheral stent placement for graft access is effective for salvaging vascular access after failed balloon angioplasty and for prolonging patency in early restenosis after balloon angioplasty. However, reinterventions are required to maintain secondary patency after stent placement. Furthermore, peripheral stent placement for graft access cannot achieve the same primary patency as balloon angioplasty alone.

  4. Product placement of computer games in cyberspace.

    PubMed

    Yang, Heng-Li; Wang, Cheng-Shu

    2008-08-01

    Computer games are considered an emerging media and are even regarded as an advertising channel. By a three-phase experiment, this study investigated the advertising effectiveness of computer games for different product placement forms, product types, and their combinations. As the statistical results revealed, computer games are appropriate for placement advertising. Additionally, different product types and placement forms produced different advertising effectiveness. Optimum combinations of product types and placement forms existed. An advertisement design model is proposed for use in game design environments. Some suggestions are given for advertisers and game companies respectively.

  5. Adaptable Deployable Entry and Placement Technology (ADEPT)

    NASA Video Gallery

    The Adaptable, Deployable Entry Placement Technology (ADEPT) Project will test and demonstrate a deployable aeroshell concept as a viable thermal protection system for entry, descent, and landing o...

  6. Automated fiber placement: Evolution and current demonstrations

    NASA Technical Reports Server (NTRS)

    Grant, Carroll G.; Benson, Vernon M.

    1993-01-01

    The automated fiber placement process has been in development at Hercules since 1980. Fiber placement is being developed specifically for aircraft and other high performance structural applications. Several major milestones have been achieved during process development. These milestones are discussed in this paper. The automated fiber placement process is currently being demonstrated on the NASA ACT program. All demonstration projects to date have focused on fiber placement of transport aircraft fuselage structures. Hercules has worked closely with Boeing and Douglas on these demonstration projects. This paper gives a description of demonstration projects and results achieved.

  7. Hepatocellular Carcinoma Complicated by Gastroduodenal Obstruction: Palliative Treatment with Metallic Stent Placement

    SciTech Connect

    Lee, Ye Jin; Kim, Jin Hyoung Song, Ho-Young; Park, Jung-Hoon; Na, Han Kyu; Kim, Pyeong Hwa; Fan, Yong

    2012-10-15

    Purpose: To evaluate the clinical effectiveness of self-expandable metallic stents in seven patients with malignant gastroduodenal obstruction caused by inoperable hepatocellular carcinoma (HCC). Methods: Seven patients with gastroduodenal obstruction caused by advanced HCC underwent metallic stent placement from 2003 to 2010. These patients had total dysphagia (n = 5) or were able to eat only liquids (n = 2) before stent placement. Patients had Eastern Cooperative Oncology Group performance scores of 2 or 3, and Child-Pugh classification B or C. Results: Stent placement was technically successful in all seven patients (100%) and clinically successful in six (86%). Five patients could eat a soft diet, and one patient tolerated regular diet after stent placement. Stent-related obstructive jaundice occurred in one patient. One patient had hematemesis 11 days after stent placement. Overall mean survival was 51 days (range, 10-119 days). Stent patency was preserved in six patients with clinical success until death. Conclusion: Placement of a covered self-expandable metallic stent may offer good palliation in patients with gastroduodenal obstruction due to advanced HCC.

  8. Effects of resisted sled towing on sprint kinematics in field-sport athletes.

    PubMed

    Lockie, Robert G; Murphy, Aron J; Spinks, Christopher D

    2003-11-01

    Weighted sled towing is a common resisted sprint training technique even though relatively little is known about the effects that such practice has on sprint kinematics. The purpose of this study was to explore the effects of sled towing on acceleration sprint kinematics in field-sport athletes. Twenty men completed a series of sprints without resistance and with loads equating to 12.6 and 32.2% of body mass. Stride length was significantly reduced by approximately 10 and approximately 24% for each load, respectively. Stride frequency also decreased, but not to the extent of stride length. In addition, sled towing increased ground contact time, trunk lean, and hip flexion. Upper-body results showed an increase in shoulder range of motion with added resistance. The heavier load generally resulted in a greater disruption to normal acceleration kinematics compared with the lighter load. The lighter load is likely best for use in a training program.

  9. Determining the optimal load for resisted sprint training with sled towing.

    PubMed

    Alcaraz, Pedro E; Palao, José Manuel; Elvira, José L L

    2009-03-01

    An excessive load in resisted sprint training can produce changes in running patterns. Therefore, load control is essential to ensure the specificity of these training methods. The most common way to control it is through the percentage of velocity lost in relation to maximum velocity. The present paper describes a study that aimed to establish the load for sprint training with sled towing. The study developed a regression equation for calculating the load in the maximum velocity phase. The calculation was done with 26 athletes from the Spanish and French national levels on a synthetic track surface and with spikes. The regression equation obtained was % body mass = (-0.8674 x % velocity) + 87.99. The equation, although specific for type of surface used and sled towing characteristics, is useful in establishing the optimal load for acceleration and maximum velocity training with sled towing.

  10. Micro-shimmy of towed structures in experimentally uncharted unstable parameter domain

    NASA Astrophysics Data System (ADS)

    Takács, Dénes; Stépán, Gábor

    2012-11-01

    In this paper, the lateral instability of towed structures (trailers, caravans and articulated buses) is investigated with special attention to the small amplitude lateral vibration that leads to a higher energy consumption in certain parameter domains. A low degree-of-freedom mechanical model of a shimmying towed tyre is used that describes the dynamics of the tyre-ground contact patch by the time delayed differential equation. Stability charts are calculated and the theoretically predicted linear unstable islands of small amplitude shimmy motions are validated by laboratory experiments. A tyre is towed by a relatively long caster, and its temperature and the input current of the conveyor belt are measured in order to show the increased value of the rolling resistance.

  11. 49 CFR 214.525 - Towing with on-track roadway maintenance machines or hi-rail vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... or hi-rail vehicles. 214.525 Section 214.525 Transportation Other Regulations Relating to... SAFETY On-Track Roadway Maintenance Machines and Hi-Rail Vehicles § 214.525 Towing with on-track roadway maintenance machines or hi-rail vehicles. (a) When used to tow pushcars or other maintenance-of-way...

  12. 46 CFR 130.250 - Mooring and towing equipment for OSVs of less than 100 gross tons.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Mooring and towing equipment for OSVs of less than 100 gross tons. 130.250 Section 130.250 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Systems § 130.250 Mooring and towing equipment for OSVs of less than 100 gross tons. Each OSV of less...

  13. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false What are the requirements for fire pumps, fire mains... the requirements for fire pumps, fire mains, and fire hoses on towing vessels? By April 29, 2005, you must provide for your towing vessel either a self-priming, power-driven, fixed fire-pump, a fire...

  14. Dynamics of Placement...How to Develop a Successful Career Planning & Placement Program.

    ERIC Educational Resources Information Center

    Shingleton, John D.; Fitzpatrick, Edwin B.

    This document presents college practitioners with a practical guide for establishing, maintaining, expanding, or revitalizing a contemporary career planning and placement center. The introduction to this guide contains a brief history of career planning and placement. Chapter 1, Career Planning and Placement in the Academic Setting, addresses the…

  15. Comparison of Curvilinear Stiffeners and Tow Steered Composites for Aeroelastic Tailoring of Transports

    NASA Technical Reports Server (NTRS)

    Stanford, Bret K.; Jutte, Christine V.

    2016-01-01

    A series of aeroelastic optimization problems are solved on a high aspect ratio wingbox of the Common Research Model, in an effort to minimize structural mass under coupled stress, buckling, and flutter constraints. Two technologies are of particular interest: tow steered composite laminate skins and curvilinear stiffeners. Both methods are found to afford feasible reductions in mass over their non-curvilinear structural counterparts, through both distinct and shared mechanisms for passively controlling aeroelastic performance. Some degree of diminishing returns are seen when curvilinear stiffeners and curvilinear fiber tow paths are used simultaneously.

  16. A numerical study for design of depth, pitch and roll control system of a towed vehicle

    SciTech Connect

    Koterayama, W.; Yamaguchi, S.; Nakamura, M.; Moriyama, A.; Akamatsu, T.

    1994-12-31

    A towed vehicle system, FLYING FISH, is under development for use in making chemical and physical measurements which enable the authors to obtain spacially continuous and real time data in an ocean mixed layer. The heave, pitch and roll of FLYING FISH are controlled by a main wing and horizontal tail wings which permit its stable attitudes and assure accurate measurements. The numerical simulation of motions was carried out to design the optimal control system of this towed vehicle system and the results gave the data for the design of the mechanical parts of the control system.

  17. The dynamic research and position estimation of the towed array during the U-turn process

    NASA Astrophysics Data System (ADS)

    Yang, J. X.; Shuai, C. G.; He, L.; Zhang, S. K.; Zhou, S. T.

    2016-09-01

    A dynamic model for estimating position of ship towed array during U-turn manoeuvre is introduced and developed. Based on this model, the influences of the parameters such as time step and segment length on the numerical simulation are analysed. The results indicate that decreasing the time step has little effect on the simulation accuracy but will increase the computational time. The selection of segment length has a great influence on the estimation of ship towed array position during U-turn manoeuvre. Reducing the segment length somewhat increases the computational complexity and significantly improves simulation precision.

  18. Eclipse project QF-106 and C-141A climbs out under tow on first tethered flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    TOW LAUNCH DEMONSTRATION - The Kelly Space & Technology (KST)/USAF/NASA Eclipse project's modified QF-106 climbs out under tow by a USAF C-141A on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, hosted the project, providing engineering and facility support as well as the project pilot. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort

  19. Exploring Continuous Clinical Placement for Undergraduate Students

    ERIC Educational Resources Information Center

    McKenna, Lisa G.; Wray, Natalie; McCall, Louise

    2009-01-01

    Clinical placements are integral to health professional preparatory courses. These placements allow for the application of classroom-based learning into real patient care situations. In doing so, they provide opportunities for applying theoretical knowledge into practice contexts, skills development and socialisation into the chosen profession.…

  20. 32 CFR 1656.10 - Job placement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Job placement. 1656.10 Section 1656.10 National....10 Job placement. (a) Selective Service will maintain a job bank for the exclusive purpose of placing ASWs in alternative service jobs. (b) An ASW who has identified his own job in accordance with §...

  1. 32 CFR 1656.10 - Job placement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Job placement. 1656.10 Section 1656.10 National....10 Job placement. (a) Selective Service will maintain a job bank for the exclusive purpose of placing ASWs in alternative service jobs. (b) An ASW who has identified his own job in accordance with §...

  2. 32 CFR 1656.10 - Job placement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Job placement. 1656.10 Section 1656.10 National....10 Job placement. (a) Selective Service will maintain a job bank for the exclusive purpose of placing ASWs in alternative service jobs. (b) An ASW who has identified his own job in accordance with §...

  3. 32 CFR 1656.10 - Job placement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Job placement. 1656.10 Section 1656.10 National....10 Job placement. (a) Selective Service will maintain a job bank for the exclusive purpose of placing ASWs in alternative service jobs. (b) An ASW who has identified his own job in accordance with §...

  4. 32 CFR 1656.10 - Job placement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Job placement. 1656.10 Section 1656.10 National....10 Job placement. (a) Selective Service will maintain a job bank for the exclusive purpose of placing ASWs in alternative service jobs. (b) An ASW who has identified his own job in accordance with §...

  5. Private Placement Debt Financing for Public Entities

    ERIC Educational Resources Information Center

    Holman, Lance S.

    2010-01-01

    Private placement financing is a debt or capital lease obligation arranged between a municipality or a 501(c) (3) not-for-profit organization and a single sophisticated institutional investor. The investor can be a bank, insurance company, finance company, hedge fund, or high-net worth individual. Private placement financing is similar to…

  6. Developing Career Planning and Placement Strategies.

    ERIC Educational Resources Information Center

    Kolvitz, Marcia, Ed.

    These three conference papers from the Biennial Conference on Postsecondary Education for Persons who are Deaf or Hard of Hearing focus on career planning and placement strategies for students with deafness or hard of hearing. The first paper, "Successful Job Development and Placement Strategies with Deaf and Hard of Hearing College…

  7. Preparing ESP Learners for Workplace Placement

    ERIC Educational Resources Information Center

    Wood, David

    2009-01-01

    Engineering students in North American universities often participate in cooperative education placements in workplaces as part of the requirements for their degrees and professional certification. Students for whom English is an L2 often experience difficulties in these placements due to the fact that while their academic language ability may be…

  8. Implementation of Job Placement Services Guidelines.

    ERIC Educational Resources Information Center

    McGillicuddy (Shirley) & Associates, Sierra Madre, CA.

    The Implementation of Job Placement Services Guidelines Project was designed to strengthen placement programs and services for California community college vocational students, and for all students needing part-time employment to realize their educational goals. The project was designed to test the validity and relevance of quality indicators…

  9. New pole placement algorithm - Polynomial matrix approach

    NASA Technical Reports Server (NTRS)

    Shafai, B.; Keel, L. H.

    1990-01-01

    A simple and direct pole-placement algorithm is introduced for dynamical systems having a block companion matrix A. The algorithm utilizes well-established properties of matrix polynomials. Pole placement is achieved by appropriately assigning coefficient matrices of the corresponding matrix polynomial. This involves only matrix additions and multiplications without requiring matrix inversion. A numerical example is given for the purpose of illustration.

  10. Understanding Successful Sandwich Placements: A Bourdieusian Approach

    ERIC Educational Resources Information Center

    Clark, Martyn; Zukas, Miriam

    2016-01-01

    Sandwich placements and other integrated work and study schemes are increasingly advocated as a key means by which universities can promote students' employability. However, there is little understanding of how successful placements work in terms of facilitating learning and development. Drawing on three longitudinal case studies of students who…

  11. Math Placement in California's Public Schools

    ERIC Educational Resources Information Center

    Gao, Niu; Adan, Sara

    2016-01-01

    Last year, the California Legislature passed a new law--the California Mathematics Placement Act--to address widespread concern over equity in the math placement process. The law is aimed at improving the measurement of student performance in order to move more students successfully through the high school curriculum. In this context, researchers…

  12. Characteristics of Work Placements Valued by Employers.

    ERIC Educational Resources Information Center

    Chivers, Barbara; Flatten, Kay

    1996-01-01

    Group Feedback Strategy was used to evaluate data from 73 employers, 18 tutors, 156 students, and 45 graduates involved in work placements in a library and information science program. Respondents showed reasonably high satisfaction for the following characteristics of placements: teamwork experience, assessment of capabilities, training…

  13. Mapping Porosity Structure Offshore Torrey Pines State Natural Reserve and Del Mar, California Using a Surface Towed EM System

    NASA Astrophysics Data System (ADS)

    Martin, Thomas Patrick

    Controlled source electromagnetic methods have been used in exploration of the offshore environment for over 50 years to map the resistivity structure of the earth. Developments in both instrumentation and computational power have lead to many advancements that have led to discoveries and insights about the subsurface. One of these advancements has been the development of towed EM acquisition systems. One system the Marine EM Lab at Scripps Institution of Oceanography has developed is a shallow water system, named Porpoise, can be used in water depths as shallow as 5m. In May of 2014, a one day field test of this new shallow water acquisition system took place offshore of Del Mar and Torrey Pines State Natural Reserve, California. The data from this field test corresponds with previous interpretations of paleochannels directly offshore modern day San Dieguito and Soledad Valley river outflows. With resistivity data, it is possible to indirectly map porosity in the near surface and to map geological features. The data dense and economical operation of the Porpoise acquisition system can be used to map resistivity and indirectly porosity in a variety of shallow water marine environments. This field test proves the viability and limitations of the Porpoise system.

  14. Genetic Algorithm Approaches for Actuator Placement

    NASA Technical Reports Server (NTRS)

    Crossley, William A.

    2000-01-01

    This research investigated genetic algorithm approaches for smart actuator placement to provide aircraft maneuverability without requiring hinged flaps or other control surfaces. The effort supported goals of the Multidisciplinary Design Optimization focus efforts in NASA's Aircraft au program. This work helped to properly identify various aspects of the genetic algorithm operators and parameters that allow for placement of discrete control actuators/effectors. An improved problem definition, including better definition of the objective function and constraints, resulted from this research effort. The work conducted for this research used a geometrically simple wing model; however, an increasing number of potential actuator placement locations were incorporated to illustrate the ability of the GA to determine promising actuator placement arrangements. This effort's major result is a useful genetic algorithm-based approach to assist in the discrete actuator/effector placement problem.

  15. 46 CFR 27.100 - What towing vessels does this part affect?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... General Provisions for Fire-Protection Measures and Fire-Suppression Equipment on Towing Vessels § 27.100... defined by 46 CFR 10.103; (iv) For response to emergency or pollution; (2) A public vessel that is both... of a fire in the engine room. (d) You must test and maintain all of the equipment required by...

  16. Influence of Tow Architecture on Compaction and Nesting in Textile Preforms

    NASA Astrophysics Data System (ADS)

    Yousaf, Z.; Potluri, P.; Withers, P. J.

    2017-04-01

    Transverse compression response of tows during processes such as vacuum infusion or autoclave curing has significant influence on resin permeability in fabrics as well as the laminate thickness, fibre volume fraction and tow orientations in the finished composite. This paper reports macro -scale deformations in dry fibre assemblies due to transverse compaction. In this study, influence of weave geometry and the presence of interlacements or stitches on the ply-level compaction as well as nesting have been investigated. 2D woven fabrics with a variety of interlacement patterns - plain, twill and sateen- as well as stitched Non-crimp (NCF) fabrics have been investigated for macro-level deformations. Compression response of single layer and multilayer stacks has been studied as a function of external pressure in order to establish nesting behaviour. It appears that the degree of individual ply compaction and degree of nesting between the plies are influenced by tow architectures. Inter-tow spacing and stitching thread thickness appears to influence the degree of nesting in non-crimp fabrics.

  17. 46 CFR 27.205 - What are the requirements for internal communication systems on towing vessels?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false What are the requirements for internal communication... requirements for internal communication systems on towing vessels? (a) You must ensure that your vessel is... required to have internal communication systems. (c) When the operating-station's engine controls and...

  18. 46 CFR 27.205 - What are the requirements for internal communication systems on towing vessels?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false What are the requirements for internal communication... requirements for internal communication systems on towing vessels? (a) You must ensure that your vessel is... required to have internal communication systems. (c) When the operating-station's engine controls and...

  19. 46 CFR 27.205 - What are the requirements for internal communication systems on towing vessels?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false What are the requirements for internal communication... requirements for internal communication systems on towing vessels? (a) You must ensure that your vessel is... required to have internal communication systems. (c) When the operating-station's engine controls and...

  20. 46 CFR 27.205 - What are the requirements for internal communication systems on towing vessels?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false What are the requirements for internal communication... requirements for internal communication systems on towing vessels? (a) You must ensure that your vessel is... required to have internal communication systems. (c) When the operating-station's engine controls and...

  1. Tracking sperm whale (Physeter macrocephalus) dive profiles using a towed passive acoustic array

    NASA Astrophysics Data System (ADS)

    Thode, Aaron

    2004-07-01

    A passive acoustic method is presented for tracking sperm whale dive profiles, using two or three hydrophones deployed as either a vertical or large-aperture towed array. The relative arrival times between the direct and surface-reflected acoustic paths are used to obtain the ranges and depths of animals with respect to the array, provided that the hydrophone depths are independently measured. Besides reducing the number of hydrophones required, exploiting surface reflections simplifies automation of the data processing. Experimental results are shown from 2002 and 2003 cruises in the Gulf of Mexico for two different towed array deployments. The 2002 deployment consisted of two short-aperture towed arrays separated by 170 m, while the 2003 deployment placed an autonomous acoustic recorder in tandem with a short-aperture towed array, and used ship noise to time-align the acoustic data. The resulting dive profiles were independently checked using single-hydrophone localizations, whenever multipath reflections from the ocean bottom could be exploited to effectively create a large-aperture vertical array. This technique may have applications for basic research and for real-time mitigation for seismic airgun surveys.

  2. 46 CFR 27.205 - What are the requirements for internal communication systems on towing vessels?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... required to have internal communication systems. (c) When the operating-station's engine controls and the... requirements for internal communication systems on towing vessels? (a) You must ensure that your vessel is... 46 Shipping 1 2011-10-01 2011-10-01 false What are the requirements for internal...

  3. Influence of Tow Architecture on Compaction and Nesting in Textile Preforms

    NASA Astrophysics Data System (ADS)

    Yousaf, Z.; Potluri, P.; Withers, P. J.

    2016-11-01

    Transverse compression response of tows during processes such as vacuum infusion or autoclave curing has significant influence on resin permeability in fabrics as well as the laminate thickness, fibre volume fraction and tow orientations in the finished composite. This paper reports macro -scale deformations in dry fibre assemblies due to transverse compaction. In this study, influence of weave geometry and the presence of interlacements or stitches on the ply-level compaction as well as nesting have been investigated. 2D woven fabrics with a variety of interlacement patterns - plain, twill and sateen- as well as stitched Non-crimp (NCF) fabrics have been investigated for macro-level deformations. Compression response of single layer and multilayer stacks has been studied as a function of external pressure in order to establish nesting behaviour. It appears that the degree of individual ply compaction and degree of nesting between the plies are influenced by tow architectures. Inter-tow spacing and stitching thread thickness appears to influence the degree of nesting in non-crimp fabrics.

  4. 33 CFR 164.76 - Towline and terminal gear for towing alongside and pushing ahead.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Towline and terminal gear for towing alongside and pushing ahead. 164.76 Section 164.76 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS §...

  5. 33 CFR 164.76 - Towline and terminal gear for towing alongside and pushing ahead.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Towline and terminal gear for towing alongside and pushing ahead. 164.76 Section 164.76 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS §...

  6. Tow-Steered Panels With Holes Subjected to Compression or Shear Loads

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.; Tatting, Brian F.; Guerdal, Zafer

    2005-01-01

    Tailoring composite laminates to vary the fiber orientations within a fiber layer of a laminate to address non-uniform stress states and provide structural advantages such as the alteration of principal load paths has potential application to future low-cost, light-weight structures for commercial transport aircraft. Evaluation of this approach requires the determination of the effectiveness of stiffness tailoring through the use of curvilinear fiber paths in flat panels including the reduction of stress concentrations around the holes and the increase in load carrying capability. Panels were designed through the use of an optimization code using a genetic algorithm and fabricated using a tow-steering approach. Manufacturing limitations, such as the radius of curvature of tows the machine could support, avoidance of wrinkling of fibers and minimization of gaps between fibers were considered in the design process. Variable stiffness tow-steered panels constructed with curvilinear fiber paths were fabricated so that the design methodology could be verified through experimentation. Finite element analysis where each element s stacking sequence was accurately defined is used to verify the behavior predicted based on the design code. Experiments on variable stiffness flat panels with central circular holes were conducted with the panels loaded in axial compression or shear. Tape and tow-steered panels are used to demonstrate the buckling, post-buckling and failure behavior of elastically tailored panels. The experimental results presented establish the buckling performance improvements attainable by elastic tailoring of composite laminates.

  7. 33 CFR 155.235 - Emergency towing capability for oil tankers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Emergency towing capability for oil tankers. 155.235 Section 155.235 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS...

  8. 33 CFR 155.235 - Emergency towing capability for oil tankers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Emergency towing capability for oil tankers. 155.235 Section 155.235 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS...

  9. 33 CFR 155.235 - Emergency towing capability for oil tankers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Emergency towing capability for oil tankers. 155.235 Section 155.235 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS...

  10. 46 CFR 11.465 - Requirements for endorsements as mate (pilot) of towing vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 30 3 of 12 YES YES NC, GL-I (2) NEAR-COASTAL (NC) 30 12 of 30 3 of 12 YES YES GL-I (3) GREAT LAKES... near coastal routes; apprentice mate (steersman), towing vessels on Great Lakes and inland routes;...

  11. 77 FR 52317 - Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active Sonar

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Department of the Navy Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active... Array Sensor System Low Frequency Active (SURTASS LFA) sonar systems with certain...

  12. 14 CFR 61.69 - Glider and unpowered ultralight vehicle towing: Experience and training requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... airline transport pilot certificate with a category rating for powered aircraft; (2) Has logged at least... this section, has logged at least three flights as the sole manipulator of the controls of an aircraft... 17, 1967, has made and logged 10 or more flights as pilot in command of an aircraft towing a...

  13. Ultrasound/fluoroscopy-assisted placement of peritoneal dialysis catheters.

    PubMed

    Maya, Ivan D

    2007-01-01

    Peritoneal dialysis (PD) catheters may be inserted blindly, surgically, and either by laparoscopic, peritoneoscopic, or fluoroscopic approach. A modified fluoroscopic technique by adding ultrasound-assistance was performed in the present study to ensure entry into the abdominal cavity under direct ultrasound visualization. From March 2005 to May 2007, ultrasound-fluoroscopic guided placement of PD catheters was attempted in 32 end-stage renal disease (ESRD) patients. Preoperative evaluation was performed on all patients prior to the procedure. After initial dissection of the subcutaneous tissue anterior to the anterior rectus sheath, the needle was inserted into the abdominal cavity under the guidance of ultrasound. The position of the epigastric artery was also examined using ultrasonography to avoid the risk of arterial injury. PD catheters were successfully placed in 31 of the 32 ESRD patients using this technique. In all of these patients, the needle could be seen entering the abdominal cavity using an ultrasound. In one patient the procedure was abandoned because of bowel puncture by the micro-puncture needle that was inadvertently advanced into a loop of bowel. This patient did not develop acute abdomen nor needed any intervention. One patient died 4 days after placement of the catheter of unrelated causes. One patient was started on acute peritoneal dialysis the same day of catheter placement without any complications. The rest of the patients started peritoneal dialysis within 2-6 weeks of catheter placement. None of the patients had bleeding related to arterial injury as ultrasound was able to visualize the epigastric artery. Our experience shows that ultrasound-fluoroscopic technique is minimally invasive and allows for accurate assessment of the entry into the abdominal cavity. This technique can avoid the risk of vascular injury altogether.

  14. Advancing beyond AP Courses

    ERIC Educational Resources Information Center

    Hammond, Bruce G.

    2009-01-01

    A quiet revolution is picking up steam in the nation's private secondary schools, with broad implications for college admissions and for teaching and learning on both sides of the transition from high school to college. About 50 of the nation's leading college-preparatory schools have opted out of the College Board's Advanced Placement (AP)…

  15. Nursing students' experience of practice placements.

    PubMed

    MacDonald, Kathleen; Paterson, Kirstie; Wallar, Jessica

    2016-11-02

    Clinical practice placements are an essential component of pre-registration nursing programmes. Integration into a new team in an unfamiliar setting, which has its own values, practices, culture and language, can be stressful for nursing students. This article presents and discusses students' reflections on preparing for, entering and leaving practice placements. Ten students who participated in fortnightly group reflective sessions, discussed and analysed their learning experiences while on practice placements in an acute hospital. The challenges the students encountered were deconstructed using a group narrative approach. The students experienced ethical dilemmas around patient dignity, consent and advocacy as well as factors external to the practice setting, such as navigating systems and processes to access information before starting practice placements, managing household duties and academic workloads while working long shifts, and managing fatigue and loneliness. The students devised recommendations for other students to enable them to navigate their practice placements effectively and enhance their learning experience. Raising awareness among academic and practice placement staff of the challenges students encounter before and during their practice placement is essential to assist students to succeed and maximise their learning potential.

  16. Enhancements of Tow-Steering Design Techniques: Design of Rectangular Panel Under Combined Loads

    NASA Technical Reports Server (NTRS)

    Tatting, Brian F.; Setoodeh, Shahriar; Gurdal, Zafer

    2005-01-01

    An extension to existing design tools that utilize tow-steering is presented which is used to investigate the use of elastic tailoring for a flat panel with a central hole under combined loads of compression and shear. The elastic tailoring is characterized by tow-steering within individual lamina as well as a novel approach based on selective reinforcement, which attempts to minimize compliance through the use of Cellular Automata design concepts. The selective reinforcement designs lack any consideration of manufacturing constraints, so a new tow-steered path definition was developed to translate the prototype selective reinforcement designs into manufacturable plies. The minimum weight design of a flat panel under combined loading was based on a model provided by NASA-Langley personnel and analyzed by STAGS within the OLGA design environment. Baseline designs using traditional straight fiber plies were generated, as well as tow-steered designs which incorporated parallel, tow-drop, and overlap plies within the laminate. These results indicated that the overlap method provided the best improvement with regards to weight and performance as compared to traditional constant stiffness monocoque panels, though the laminates did not measure up to similar designs from the literature using sandwich and isogrid constructions. Further design studies were conducted using various numbers of the selective reinforcement plies at the core and outer surface of the laminate. None of these configurations exhibited notable advantages with regard to weight or buckling performance. This was due to the fact that the minimization of the compliance tended to direct the major stresses toward the center of the panel, which decreased the ability of the structure to withstand loads leading to instability.

  17. Content Selection in Advanced Courses

    ERIC Educational Resources Information Center

    Parker, Walter C.; Lo, Jane C.

    2016-01-01

    Advanced high-school courses, such as Advanced Placement (AP) courses in the United States, present a content selection conundrum of major proportions. Judicious content selection is necessary if students are to learn subject matter meaningfully, but the sheer breadth of tested material in these courses promotes nearly the opposite:…

  18. Educational Placement of Children with Spina Bifida.

    ERIC Educational Resources Information Center

    Lauder, Calvin E.; And Others

    1979-01-01

    Procedures of school placement for 38 children (ages 5 to 18 years) with spina bifida in 23 school districts in western New York State were studied 5 years after a mandated process was enacted. (Author)

  19. M2-F1 in flight over lakebed on tow line

    NASA Technical Reports Server (NTRS)

    1963-01-01

    After initial ground-tow flights of the M2-F1 using the Pontiac as a tow vehicle, the way was clear to make air tows behind a C-47. The first air tow took place on 16 August 1963. Pilot Milt Thompson found that the M2-F1 flew well, with good control. This first flight lasted less than two minutes from tow-line release to touchdown. The descent rate was 4,000 feet per minute. The wingless, lifting body aircraft design was initially concieved as a means of landing an aircraft horizontally after atmospheric reentry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Dryden management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a 'flying bathtub,' and was designated the M2-F1, the 'M' referring to 'manned' and 'F' referring to 'flight' version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds up to about 120 mph. This vehicle needed to be able to tow the M2-F1 on the Rogers Dry Lakebed adjacent to NASA's Flight Research Center (FRC) at a minimum speed of 100 miles per hour. To do that, it had to handle the 400-pound pull of the M2-F1. Walter 'Whitey' Whiteside, who was a retired Air Force maintenance officer working in the FRC's Flight Operations Division, was a dirt-bike rider and hot-rodder. Together with Boyden 'Bud' Bearce in the Procurement and Supply Branch of the FRC, Whitey acquired a Pontiac Catalina convertible with the largest engine available. He took the car to Bill Straup's renowned hot-rod shop near Long Beach for modification. With a special gearbox and racing slicks, the Pontiac could tow the 1,000-pound M2-F1 110 miles per hour in 30 seconds. It proved adequate for the roughly 400 car tows that got

  20. PEG feeding tube placement and aftercare.

    PubMed

    Haywood, Sharlene

    Some adults and children are unable to swallow or eat and drink enough. Insertion of a percutaneous endoscopic gastrostomy (PEG) tube may enable long-term feeding, fluid and/or medication administration. The procedure involves gastroscopy under sedation to identify tube placement site, place the tube and check it has been placed correctly. Serious complications include peritonitis and perforation of the colon. Frequent observations immediately after placement are essential. With good nursing care, complications can be avoided or dealt with promptly.

  1. A small towed beamforming array to identify vocalizing resident killer whales ( Orcinus orca) concurrent with focal behavioral observations

    NASA Astrophysics Data System (ADS)

    Miller, Patrick J.; Tyack, Peter L.

    Investigations of communication systems benefit from concurrent observation of vocal and visible behaviors of individual animals. A device has been developed to identify individual vocalizing resident killer whales ( Orcinus orca) during focal behavioral observations. The device consists of a 2-m, 15-element hydrophone array, which is easily towed behind a small vessel, on-board multi-channel recorders, and real-time signal processing equipment. Acoustic data from the hydrophones are digitized and processed using broadband frequency-domain beamforming to yield frequency-azimuth (FRAZ) and "directo-gram" displays of arriving sounds. Based upon statistical analysis of independent portions of typical killer whale calls, the precision of the angle-of-arrival estimate ranges from ±0° to ±2.5° with a mean precision of ±1.5°. Echolocation clicks also are resolved precisely with a typical -6 dB mainlobe width of ±2.0°. Careful positioning of the array relative to the animals minimizes the effects of depth ambiguities and allows identification of individual sources in many circumstances. Several strategies for identifying vocalizing individuals are discussed and an example of a successful identification is described. Use of the array with resident killer whales did not interfere with vessel maneuverability, animal tracking, or behavioral sampling of focal individuals. This localization technique has promise for advancing the abilities of researchers to conduct unbiased behavioral and acoustic sampling of individual free-ranging cetaceans.

  2. Use of Modal Acoustic Emission to Monitor Damage Progression in Carbon Fiber/Epoxy Tows and Implications for Composite Structures

    NASA Technical Reports Server (NTRS)

    Waller, Jess M.; Saulsberry, Regor L.; Nichols, Charles T.; Wentzel, Daniel J.

    2010-01-01

    This slide presentation reviews the use of Modal Acoustic Emission to monitor damage progression to carbon fiber/epoxy tows. There is a risk for catastrophic failure of composite overwrapped pressure vessels (COPVs) due to burst-before-leak (BBL) stress rupture (SR) failure of carbon-epoxy (C/Ep) COPVs. A lack of quantitative nondestructive evaluation (NDE) is causing problems in current and future spacecraft designs. It is therefore important to develop and demonstrate critical NDE that can be implemented during stages of the design process since the observed rupture can occur with little of no advanced warning. Therefore a program was required to develop quantitative acoustic emission (AE) procedures specific to C/Ep overwraps, but which also have utility for monitoring damage accumulation in composite structure in general, and to lay the groundwork for establishing critical thresholds for accumulated damage in composite structures, such as COPVs, so that precautionary or preemptive engineering steps can be implemented to minimize of obviate the risk of catastrophic failure. A computed Felicity Ratio (FR) coupled with fast Fourier Transform (FFT) frequency analysis shows promise as an analytical pass/fail criterion. The FR analysis and waveform and FFT analysis are reviewed

  3. 41 CFR 60-2.16 - Placement goals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... good faith effort to make all aspects of the entire affirmative action program work. Placement goals... placement goal for a particular job group, the contractor must establish a percentage annual placement goal... job group. (d) The placement goal-setting process described above contemplates that contractors...

  4. Transhepatic Guidance of Translumbar Hemodialysis Catheter Placement in the Setting of Chronic Infrarenal IVC Occlusion

    SciTech Connect

    Lorenz, Jonathan M. Regalado, Sidney; Navuluri, Rakesh Zangan, Steven; Thuong Van Ha; Funaki, Brian

    2010-06-15

    When patients with end-stage renal disease have exhausted both conventional and unconventional venous access options, creative solutions must be sought for hemodialysis catheter placement in order to ensure survival. This case describes a patient in urgent need of a dialysis catheter despite total occlusion of the jugular, subclavian, and femoral veins. Occlusion of the inferior vena cava (IVC) and right renal vein resulted in failed attempts at translumbar catheter placement. A gooseneck snare was temporarily advanced through the liver to the IVC for use as a fluoroscopic target to facilitate successful single-puncture, translumbar catheterization.

  5. Dynamics modeling of a semi-submersible autonomous underwater vehicle with a towfish towed by a cable

    NASA Astrophysics Data System (ADS)

    Park, Jinmo; Kim, Nakwan

    2015-06-01

    In this paper, we employ a dynamics modeling method for investigating a multi-body dynamics system of semi-submersible autonomous underwater vehicles consisting of a towing vehicle operated near the water surface, a tow cable, and a towfish. The towfish, which is towed by a marine cable for the purposes of exploration or mine hunting, is modeled with a Six-Degree-of-Freedom (6-DOF) equation of motion that reflects its hydrodynamics characteristics. The towing cable, which can experience large displacements and deformations, is modeled using an absolute nodal coordinate formulation. To reflect the hydrodynamic characteristics of the cable during motion, the hydrodynamic force due to added mass and the drag force are imposed. To verify the completeness of the modeling, a few simple numerical simulations were conducted, and the results confirm the physical plausibility of the model.

  6. X-34 being towed by the Mobile Operations Module during navigational tests on the Rogers Dry Lakebed

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Following initial captive flight tests last year at NASA's Dryden Flight Research Center, Edwards Air Force Base, California, the X-34 technology demonstrator began a new series of tests last week in which it is being towed behind a semi-truck and released to coast on the Edwards dry lakebed. On July 20, 2000, it was towed and released twice at speeds of five and 10 miles per hour. On July 24, 2000, it was towed and released twice at 10 and 30 miles per hour. Twelve tests are planned during which the X-34 will be towed for distances up to 10,000 feet and released at speeds up to 80 miles per hour. The test series is expected to last at least six weeks.

  7. 49 CFR 214.525 - Towing with on-track roadway maintenance machines or hi-rail vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... towing would cause the machine or hi-rail vehicle to exceed the capabilities of its braking system. In determining the limit of the braking system, the employer must consider the track grade (slope), as well...

  8. 49 CFR 214.525 - Towing with on-track roadway maintenance machines or hi-rail vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... towing would cause the machine or hi-rail vehicle to exceed the capabilities of its braking system. In determining the limit of the braking system, the employer must consider the track grade (slope), as well...

  9. 49 CFR 214.525 - Towing with on-track roadway maintenance machines or hi-rail vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... towing would cause the machine or hi-rail vehicle to exceed the capabilities of its braking system. In determining the limit of the braking system, the employer must consider the track grade (slope), as well...

  10. 49 CFR 214.525 - Towing with on-track roadway maintenance machines or hi-rail vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... towing would cause the machine or hi-rail vehicle to exceed the capabilities of its braking system. In determining the limit of the braking system, the employer must consider the track grade (slope), as well...

  11. A Transition Course from Advanced Placement to College Calculus

    ERIC Educational Resources Information Center

    Lucas, Timothy A.; Spivey, Joseph

    2011-01-01

    In the Spring of 2007, a group of highly motivated mathematics graduate students conducted a review of Duke's Calculus curriculum. They focused on two main problems. The first problem is the result of a very positive trend: a growing number of students are earning AP credit for Calculus I in high school. However, this results in Calculus II…

  12. The Advanced Placement and International Baccalaureate Programs: The Graduates' Perspective

    ERIC Educational Resources Information Center

    Smith, Shannon Saxby

    2009-01-01

    This study was designed to solicit the perspectives of AP and IB graduates who have completed at least one semester of postsecondary education about their experiences while in their respective programs. This study was also conducted to determine whether these IB graduates report that they were better prepared for postsecondary studies than…

  13. Gender Differences in STEM Related Advanced Placement Exams

    ERIC Educational Resources Information Center

    Morris, Jill B.

    2013-01-01

    Purpose: The purpose of this study was to examine differences between boys and girls in their performance on STEM related AP exams. Specifically, gender differences were examined for the following STEM related AP exams: Calculus AB, Calculus BC, Physics B, Physics C: Electricity and Magnetism, Physics C: Mechanics, Chemistry, and Computer Science…

  14. Action Biology. Advanced Placement for the Second Year. First Edition.

    ERIC Educational Resources Information Center

    Davis, Mary Pitt

    This document provides biology experiments designed for students who have completed a first year biology course. This self contained laboratory booklet contains four sections. In section 1, "Instrumentation in the Study of Cells," discussion sections and suggestions for teacher demonstrations are provided. It also includes some basic materials…

  15. CURRICULUM GUIDES IN PHYSICS--GENERAL ADVANCED PLACEMENT, COLLEGE LEVEL.

    ERIC Educational Resources Information Center

    WESNER, GORDON E.

    THE GENERAL PHYSICS CURRICULUM IS PLANNED FOR THOSE WHOSE GENERAL ABILITY IS BETTER THAN AVERAGE AND IS OFFERED IN GRADES 11 OR 12. GENERAL OBJECTIVES ARE, TO DEVELOP CRITICAL THINKING THROUGH THE SCIENTIFIC METHOD, TO UNDERSTAND BASIC PHYSICAL LAWS AND MAN'S PLACE IN THE UNIVERSE, AND TO DEVELOP A SCIENTIFIC ABILITY AND INTEREST. ELEVEN UNITS OF…

  16. Writing to Learn Statistics in an Advanced Placement Statistics Course

    ERIC Educational Resources Information Center

    Northrup, Christian Glenn

    2012-01-01

    This study investigated the use of writing in a statistics classroom to learn if writing provided a rich description of problem-solving processes of students as they solved problems. Through analysis of 329 written samples provided by students, it was determined that writing provided a rich description of problem-solving processes and enabled…

  17. Job Placement and Career Advancement of Gerontology Master's Degree Graduates.

    ERIC Educational Resources Information Center

    Peterson, David A.

    1987-01-01

    Survey of graduates of 15 gerontology master's degree programs indicated that employment roles and agencies were primarily administrative, not direct service. Most graduates accepted positions immediately after graduate school; others moved into them after holding other positions. Gerontology degree holders appear to be finding appropriate…

  18. Closing the Diversity Gap in Advanced Placement Course Enrollment

    ERIC Educational Resources Information Center

    VanSciver, James H.

    2006-01-01

    Although the myth of public education as the "great equalizer" is alive and well in the minds of many, the reality is that the notion of public schools as the savior of the less fortunate is fundamentally compromised when institutional decision making does more to suppress low-income and minority students through low expectations…

  19. M2-F1 in flight during low-speed car tow

    NASA Technical Reports Server (NTRS)

    1963-01-01

    The M2-F1 shown in flight during a low-speed car tow runs across the lakebed. Such tests allowed about two minutes to test the vehicle's handling in flight. NASA Flight Research Center (later redesignated the Dryden Flight Research Center) personnel conducted as many as 8 to 14 ground-tow flights in a single day either to test the vehicle in preparation for air tows or to train pilots to fly the vehicle before they undertook air tows. The wingless, lifting body aircraft design was initially concieved as a means of landing an aircraft horizontally after atmospheric reentry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Dryden management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a 'flying bathtub,' and was designated the M2-F1, the 'M' referring to 'manned' and 'F' referring to 'flight' version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds up to about 120 mph. This vehicle needed to be able to tow the M2-F1 on the Rogers Dry Lakebed adjacent to NASA's Flight Research Center (FRC) at a minimum speed of 100 miles per hour. To do that, it had to handle the 400-pound pull of the M2-F1. Walter 'Whitey' Whiteside, who was a retired Air Force maintenance officer working in the FRC's Flight Operations Division, was a dirt-bike rider and hot-rodder. Together with Boyden 'Bud' Bearce in the Procurement and Supply Branch of the FRC, Whitey acquired a Pontiac Catalina convertible with the largest engine available. He took the car to Bill Straup's renowned hot-rod shop near Long Beach for modification. With a special gearbox and racing slicks, the Pontiac could tow the 1,000-pound M2-F1 110 miles per hour in 30

  20. ISAAC Advanced Composites Research Testbed

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Stewart, Brian K.; Martin, Robert A.

    2014-01-01

    The NASA Langley Research Center is acquiring a state-of-art composites fabrication capability to support the Center's advanced research and technology mission. The system introduced in this paper is named ISAAC (Integrated Structural Assembly of Advanced Composites). The initial operational capability of ISAAC is automated fiber placement, built around a commercial system from Electroimpact, Inc. that consists of a multi-degree of freedom robot platform, a tool changer mechanism, and a purpose-built fiber placement end effector. Examples are presented of the advanced materials, structures, structural concepts, fabrication processes and technology development that may be enabled using the ISAAC system. The fiber placement end effector may be used directly or with appropriate modifications for these studies, or other end effectors with different capabilities may either be bought or developed with NASA's partners in industry and academia.

  1. Adaption of the Magnetometer Towed Array geophysical system to meet Department of Energy needs for hazardous waste site characterization

    SciTech Connect

    Cochran, J.R.; McDonald, J.R.; Russell, R.J.; Robertson, R.; Hensel, E.

    1995-10-01

    This report documents US Department of Energy (DOE)-funded activities that have adapted the US Navy`s Surface Towed Ordnance Locator System (STOLS) to meet DOE needs for a ``... better, faster, safer and cheaper ...`` system for characterizing inactive hazardous waste sites. These activities were undertaken by Sandia National Laboratories (Sandia), the Naval Research Laboratory, Geo-Centers Inc., New Mexico State University and others under the title of the Magnetometer Towed Array (MTA).

  2. Effects of Fiber Coatings on Tensile Properties of Hi-Nicalon SiC/RBSN Tow Composites

    NASA Technical Reports Server (NTRS)

    Bhatt, Ramakrishna T.; Hull, David R.

    1997-01-01

    Uncoated Hi-Nicalon silicon carbide (SiC) fiber tows and those coated with a single surface layer of pyrolytic boron nitride (PBN), double layers of PBN/Si-rich PBN, and boron nitride (BN)/SiC coatings deposited by chemical vapor deposition (CVD) method were infiltrated with silicon slurry and then exposed to N2, for 4 hr at 1200 and 1400 C. Room temperature ultimate tensile fracture loads and microstructural characterization of uncoated and CVD coated Hi-Nicalon SiC fiber reinforced reaction-bonded silicon nitride (RBSN) tow composites were measured to select suitable interface coating(s) stable under RBSN processing conditions. Results indicate that room temperature ultimate fracture loads of the uncoated Hi-Nicalon SiC/RBSN tow composites nitrided at both temperatures were significantly lower than those of the uncoated Hi-Nicalon tows without slurry infiltration. In contrast, all CVD coated Hi-Nicalon SiC/RBSN tow composites retained a greater fraction of the dry tow fracture load after nitridation at 1200 C, but degraded significantly after nitridation at 1400 C. Reaction between metal impurities (Fe and Ni) present in the attrition milled silicon powder and uncoated regions of SiC fibers appears to be the probable cause for fiber degradation.

  3. First results of a deep tow CHIRP sonar seafloor imaging system

    USGS Publications Warehouse

    Parent, M.; Fang, Changle; O'Brien, Thomas F.; Danforth, William W.

    1993-01-01

    The latest and most innovative technology has been applied towards the development of a full-ocean depth multi-sensor sonar system using linear swept-FM (Chirp) technology. The seafloor imaging system (SIS- 7000) described herein uses Chirp sidescan sonar to provide high resolution imagery at long range, and Chirp subbottom sonar to provide high resolution profiles in both the near bottom and deeper subbottom. The tow vehicle contains a suite of full-ocean depth instrumentation for measuring various oceanographic parameters and for monitoring vehicle status. Top side systems include a sonar display and data logging system as well as real-time sensor status display and tow vehicle control system. This paper will present an overview of this system, describe its technology and capabilities, and present some initial results. 

  4. DOA estimation based on multiple beamspace measurements sparse reconstruction for manoeuvring towed array

    NASA Astrophysics Data System (ADS)

    Yuan, J.; Xiao, H.; Cai, Z. M.; Xi, C.

    2017-01-01

    The port-starboard ambiguity in the conventional single towed linear array sonar is one of the most deceiving obstacles which exist in the way of development of spatial spectrum estimation. In order to improve the performance of target detection and Direction of Arrival (DOA) estimation, this paper proposes a novel spatial spectrum sparse reconstruction method based on multiple beamspace measurements (MBM-SR). An array sparse signal model for manoeuvring towed array is established. Then the Mutual Incoherent Property (MIP) is analyzed to ensure the proposed algorithm possessing better spatial spectrum reconstruction property. Simulation results demonstrate that, compared with Conventional Beam Forming (CBF) algorithm, the proposed algorithm has evident advantage in ambiguity suppression ratio (ASR) and estimation performance.

  5. Flight Tests Results from Supersonic Deployment of an 18-Foot Diameter Towed Ballute Decelerator

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Flight Tests Results from Supersonic Deployment of an 18-Foot Diameter (5.49 meter) Towed Ballute Decelerator. A ram-air-inflated, towed ballute decelerator having a maximum frontal diameter of 18 feet (5.49 meters) was deployed during free flight at a Mach number of 3.15 and a dynamic pressure of 38.5 lb/ft(exp 2) (1843.4 newtons/m(exp 2)). Deployment and extraction of the test ballute were normal but inflation stopped about 1 second after mortar firing and produced an average plateau drag force of 1500 pounds (6.7 kN) for about 1 second. Approximately 30 percent of expected total frontal area was obtained. [Entire movie available on DVD from CASI as Doc ID 20070031011. Contact help@sti.nasa.gov

  6. Simultaneous Magnetometer and EM61 MK2 Vehicle-Towed Array for Wide Area Assessment

    DTIC Science & Technology

    2008-09-01

    years old whereas other portions were only designed to survive a single 2002 APG fielding, the system is best operated by its inventors . Through...check, cleaning air filters, and greasing the axles of the tow platform. Major unforeseen problems included persistent jamming of our GPS base-to-radio...coils are deployed on their native wheels ). Although the system is capable of using EM61 upper coils and employing the “D” setting on the electronics

  7. Moored and Towed Measurements of Lee Waves at West Mariana Ridge

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Moored and Towed Measurements of Lee Waves at West...interested in the general problems of internal waves and ocean mixing. Breaking of internal waves is the main cause for ocean mixing away from surface...climate models. A special type of internal waves are lee waves, generated as low frequency currents interact with the bottom topography. The research

  8. Towing tests of models as an aid in the design of seaplanes

    NASA Technical Reports Server (NTRS)

    Schroder, P

    1932-01-01

    This report concerns the making and evaluation of a towing test of a seaplane float system. Some of the topics considered are: 1) the influence of the wing cell and power plant on the take-off performance; 2) the determination of the resistance curve for the take-off free to trim; 3) the resistance curves with elevator control (at fixed trims); 4) take-off time and take-off run.

  9. 46 CFR 11.464 - Requirements for endorsements as master of towing vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 4 5 6 (1) OCEANS (O) 48 18 of 48 12 of 18 3 of 18 NC, GL-I (2) NEAR-COASTAL (NC) 48 18 of 48 12 of... endorsement-as mate (pilot) of towing vessels for a route superior to your current route on which you have no... limited local area within the scope of your current route. (d) Before you serve as master of...

  10. Lightweight Towed Howitzer Demonstrator. Phase 1 and Partial Phase 2. Volume A. Overview.

    DTIC Science & Technology

    1987-04-01

    howitzer, recoil energy recovery, recoil mechanismdu4*0.tal matrix compo- sites, titanium muzzle brake, titanium platform, titanium spade, titanium walking ...220 Reservoir Accumulator C/230 Towing Stability C/240 Traverse Actuator C/250 Tube Interface C/260 Tube Laying Accuracy C/270 Walking Beam Actuators A...280 Trail Bulkhead D1/290 Walking Beam Assembly D1/300 Wheel Bubs D2 Structural Analysis of Cradle D2/050 Table of Contents D2/100 Structural

  11. Ocean eddy structure by satellite radar altimetry required for iceberg towing

    USGS Publications Warehouse

    Campbell, W.J.; Cheney, R.E.; Marsh, J.G.; Mognard, N.M.

    1980-01-01

    Models for the towing of large tabular icebergs give towing speeds of 0.5 knots to 1.0 knots relative to the ambient near surface current. Recent oceanographic research indicates that the world oceans are not principally composed of large steady-state current systems, like the Gulf Stream, but that most of the ocean momentum is probably involved in intense rings, formed by meanders of the large streams, and in mid-ocean eddies. These rings and eddies have typical dimensions on the order of 200 km with dynamic height anomalies across them of tens-of-centimeters to a meter. They migrate at speeds on the order of a few cm/sec. Current velocities as great as 3 knots have been observed in rings, and currents of 1 knot are common. Thus, the successful towing of icebergs is dependent on the ability to locate, measure, and track ocean rings and eddies. To accomplish this systematically on synoptic scales appears to be possible only by using satelliteborne radar altimeters. Ocean current and eddy structures as observed by the radar altimeters on the GEOS-3 and Seasat-1 satellites are presented and compared. Several satellite programs presently being planned call for flying radar altimeters in polar or near-polar orbits in the mid-1980 time frame. Thus, by the time tows of large icebergs will probably be attempted, it is possible synoptic observations of ocean rings and eddies which can be used to ascertain their location, size, intensity, and translation velocity will be a reality. ?? 1980.

  12. Transforming Pristine Carbon Fiber Tows into High Performance Solid-State Fiber Supercapacitors.

    PubMed

    Yu, Dingshan; Zhai, Shengli; Jiang, Wenchao; Goh, Kunli; Wei, Li; Chen, Xudong; Jiang, Rongrong; Chen, Yuan

    2015-09-02

    A facile activation strategy can transform pristine carbon fiber tows into high-performance fiber electrodes with a specific capacitance of 14.2 F cm(-3) . The knottable fiber supercapacitor shows an energy density of 0.35 mW h cm(-3) , an ultrahigh power density of 3000 mW cm(-3) , and a remarkable capacitance retention of 68%, when the scan rate increases from 10 to 1000 mV s(-1) .

  13. Organization, Operation, and Evaluation of Community College Placement Programs. Proceedings: Career Placement Workshop.

    ERIC Educational Resources Information Center

    Larsen, Howard B., Ed.; Karr, Susan, Ed.

    This publication seeks to examine the problems and practical concerns related to the organization and operation of an effective community college placement program. Using presentations given in workshops, basic information in four critical areas of placement activities in the community college is provided. First, a presentation by B. Keith Duffin…

  14. The Placement Process at Colorado Mountain College: Placement Testing and the Advising Matrix.

    ERIC Educational Resources Information Center

    Hadden, Craig

    At Colorado Mountain College (CMC), academic advising is based upon a comparison of students' basic skills with the skill requirements of individual courses. Students who enter CMC to obtain a degree must take placement tests in writing, reading, math, and study skills before they can enroll in classes. The placement test battery includes a…

  15. College Mathematics Placement Tests: Student Perceptions of Preparation and Appropriateness of Placement

    ERIC Educational Resources Information Center

    Magee, Pamela Ann

    2010-01-01

    An increasing number of recent high school graduates' college math placement test results indicate that they are not ready for college level math. This study examined the perceptions of recent high school graduates enrolled in developmental math classes to determine their level of satisfaction with their math placement, the relationship of…

  16. Effect of SRAF placement on process window for technology nodes that uses variable etch bias

    NASA Astrophysics Data System (ADS)

    Seoud, Ahmed M.; Tawfik, Tamer M.

    2009-10-01

    As technology advances to 45 nm node and below, the induced effects of etch process have an increasing contribution to the device critical dimension error budget. Traditionally, original design target shapes are drawn based on the etch target. During mask correction, etch modeling is essential to predict the new resist target that will print on the wafer. This step is known as "Model Based Retargeting" (MBR). During the initial phase of process characterization, the sub-resolution assist features (SRAF) are optimized whether based on the original design target shapes or based on a biased version of the design target (resist target). The goal of the work is to study the different possibilities of SRAF placement to maximize the accuracy and process window immunity of the final resist contour image. We will, statistically, analyze and compare process window simulation results due to various SRAFs placements by changing the reference layer used during placement.

  17. Advanced composite fuselage technology

    NASA Technical Reports Server (NTRS)

    Ilcewicz, Larry B.; Smith, Peter J.; Horton, Ray E.

    1993-01-01

    Boeing's ATCAS program has completed its third year and continues to progress towards a goal to demonstrate composite fuselage technology with cost and weight advantages over aluminum. Work on this program is performed by an integrated team that includes several groups within The Boeing Company, industrial and university subcontractors, and technical support from NASA. During the course of the program, the ATCAS team has continued to perform a critical review of composite developments by recognizing advances in metal fuselage technology. Despite recent material, structural design, and manufacturing advancements for metals, polymeric matrix composite designs studied in ATCAS still project significant cost and weight advantages for future applications. A critical path to demonstrating technology readiness for composite transport fuselage structures was created to summarize ATCAS tasks for Phases A, B, and C. This includes a global schedule and list of technical issues which will be addressed throughout the course of studies. Work performed in ATCAS since the last ACT conference is also summarized. Most activities relate to crown quadrant manufacturing scaleup and performance verification. The former was highlighted by fabricating a curved, 7 ft. by 10 ft. panel, with cocured hat-stiffeners and cobonded J-frames. In building to this scale, process developments were achieved for tow-placed skins, drape formed stiffeners, braided/RTM frames, and panel cure tooling. Over 700 tests and supporting analyses have been performed for crown material and design evaluation, including structural tests that demonstrated limit load requirements for severed stiffener/skin failsafe damage conditions. Analysis of tests for tow-placed hybrid laminates with large damage indicates a tensile fracture toughness that is higher than that observed for advanced aluminum alloys. Additional recent ATCAS achievements include crown supporting technology, keel quadrant design evaluation, and

  18. D-558-2 being towed on lakebed

    NASA Technical Reports Server (NTRS)

    1949-01-01

    In this 1949 photograph a D-558-2 is being towed across Rogers Dry Lakebed at Edwards Air Force Base. The aircraft is still equipped with a jet engine, used for ground takeoffs. On the tail of the Skyrocket is the old NACA shield, replaced in the 1950s by a yellow band and a winged 'NACA.' The Douglas D-558-2 'Skyrockets' were among the early transonic research airplanes like the X-1, X-4, X-5, and X-92A. Three of the single-seat, swept-wing aircraft flew from 1948 to 1956 in a joint program involving the National Advisory Committee for Aeronautics (NACA), with its flight research done at the NACA's Muroc Flight Test Unit in Calif., redesignated in 1949 the High-Speed Flight Research Station (HSFRS). Also partners in the flight research were the Navy-Marine Corps and the Douglas Aircraft Co. The HSFRS became the High-Speed Flight Station in 1954 and is now known as the NASA Dryden Flight Research Center. The Skyrocket made aviation history when it became the first airplane to fly twice the speed of sound. The 2 in the aircraft's designation referred to the fact that the Skyrocket was the phase-two version of what had originally been conceived as a three-phase program, with the phase-one aircraft having straight wings. The third phase, which never came to fruition, would have involved constructing a mock-up of a combat-type aircraft embodying the results from the testing of the phase one and two aircraft. Douglas pilot John F. Martin made the first flight at Muroc Army Airfield (later renamed Edwards Air Force Base) in Calif. on February 4, 1948. The goals of the program were to investigate the characteristics of swept-wing aircraft at transonic and supersonic speeds with particular attention to pitch-up (uncommanded rotation of the nose of the airplane upwards)--a problem prevalent in high-speed service aircraft of that era, particularly at low speeds during take-off and landing and in tight turns. The three aircraft gathered a great deal of data about pitch-up and

  19. M2-F1 in flight over lakebed on tow line

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Following the first M2-F1 airtow flight on 16 August 1963, the Flight Research Center used the vehicle for both research flights and to check out new lifting-body pilots. These included Bruce Peterson, Don Mallick, Fred Haise, and Bill Dana from NASA. Air Force pilots who flew the M2-F1 included Chuck Yeager, Jerry Gentry, Joe Engle, Jim Wood, and Don Sorlie, although Wood, Haise, and Engle only flew on car tows. In the three years between the first and last flights of the M2-F1, it made about 400 car tows and 77 air tows. The wingless, lifting body aircraft design was initially concieved as a means of landing an aircraft horizontally after atmospheric reentry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Dryden management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a 'flying bathtub,' and was designated the M2-F1, the 'M' referring to 'manned' and 'F' referring to 'flight' version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds up to about 120 mph. This vehicle needed to be able to tow the M2-F1 on the Rogers Dry Lakebed adjacent to NASA's Flight Research Center (FRC) at a minimum speed of 100 miles per hour. To do that, it had to handle the 400-pound pull of the M2-F1. Walter 'Whitey' Whiteside, who was a retired Air Force maintenance officer working in the FRC's Flight Operations Division, was a dirt-bike rider and hot-rodder. Together with Boyden 'Bud' Bearce in the Procurement and Supply Branch of the FRC, Whitey acquired a Pontiac Catalina convertible with the largest engine available. He took the car to Bill Straup's renowned hot-rod shop near Long Beach for modification. With a special gearbox and

  20. Carded Tow Real-Time Color Assessment: A Spectral Camera-Based System

    PubMed Central

    Furferi, Rocco; Governi, Lapo; Volpe, Yary; Carfagni, Monica

    2016-01-01

    One of the most important parameters to be controlled during the production of textile yarns obtained by mixing pre-colored fibers, is the color correspondence between the manufactured yarn and a given reference, usually provided by a designer or a customer. Obtaining yarns from raw pre-colored fibers is a complex manufacturing process entailing a number of steps such as laboratory sampling, color recipe corrections, blowing, carding and spinning. Carding process is the one devoted to transform a “fuzzy mass” of tufted fibers into a regular mass of untwisted fibers, named “tow”. During this process, unfortunately, the correspondence between the color of the tow and the target one cannot be assured, thus leading to yarns whose color differs from the one used for reference. To solve this issue, the main aim of this work is to provide a system able to perform a spectral camera-based real-time measurement of a carded tow, to assess its color correspondence with a reference carded fabric and, at the same time, to monitor the overall quality of the tow during the carding process. Tested against a number of differently colored carded fabrics, the proposed system proved its effectiveness in reliably assessing color correspondence in real-time. PMID:27589765

  1. A Study of Strength Transfer from tow to Textile Composite Using Different Reinforcement Architectures

    NASA Astrophysics Data System (ADS)

    Cristian, Irina; Nauman, Saad; Boussu, Francois; Koncar, Vladan

    2012-06-01

    The paper proposes an experimental and analytical approach of designing composites with the predetermined ultimate strength, reinforced with warp interlock fabrics. In order to better understand the phenomena of transfer of tensile properties from a tow to the composite, intermediate phases of composite manufacturing have also been taken into account and tensile properties of tows taken from the loom and the woven reinforcements have also been tested. Process of transfer of mechanical properties of raw materials to the final product (composite) depends on various structural factors. Here the influence of weave structure, which ultimately influences crimp has been studied. A strength transfer coefficient has been proposed which helps in estimating the influence of architectural parameters on 3D woven composites. 3 woven interlock reinforcements were woven to form composites. The coefficients of strength transfer were calculated for these three variants. The structural parameters were kept the same for these three reinforcements except for the weave structure. In was found that the phenomenon of strength transfer from tow to composite is negatively influenced by the crimp. In general the strength transfer coefficients have higher values for dry reinforcements and afterwards due to resin impregnation the values drop.

  2. Surgical safety of cervical pedicle screw placement with computer navigation system.

    PubMed

    Shimokawa, Nobuyuki; Takami, Toshihiro

    2017-04-01

    Cervical pedicle screw (CPS) may be the biomechanically best system for posterior cervical segmental fixation, but may carry a surgery-related risk. The purpose of this study was to evaluate the safety of CPS placement using computer navigation system for posterior cervical instrumented fixation and discuss its complication avoidance and management. Posterior cervical instrumented fixation using CPS was performed in a total of 128 patients during the period between 2007 and 2015. Intraoperative image guidance was achieved using a preoperative 3D CT-based or an intraoperative 3D CT-based navigation system. A total of 762 CPSs were placed in the spine level of C2 to Th3. The radiological accuracy of CPS placement was evaluated using postoperative CT. Accuracy of CPS placement using a preoperative 3D CT-based navigation system was 93.6 % (423 of 452 screws) in grade 0; the screw was completely contained in the pedicle, and accuracy of CPS placement using an intraoperative 3D CT-based navigation system was a little bit improved to 97.1 % (301 of 310 screws) in grade 0. CPS misplacement (more than half of screw) was 3.3 % (15 of 452 screws) using a preoperative 3D CT-based navigation system, and CPS misplacement (more than half of screw) was 0.6 % (2 of 310 screws) using an intraoperative 3D CT-based navigation system. In total, 38 screws (5.0 %) were found to perforate the cortex of pedicle, although any neural or vascular complications closely associated with CPS placement were not encountered. Twenty nine of 38 screws (76.3 %) were found to perforate laterally, and seven screws (18.4 %) were found to perforate medially. Image-guided CPS placement has been an important advancement to secure the safe surgery, although the use of CPS placement needs to be carefully determined based on the individual pathology.

  3. Primary TEP placement in patients with laryngopharyngeal free tissue reconstruction and salivary bypass tube placement.

    PubMed

    Divi, Vasu; Lin, Derrick T; Emerick, Kevin; Rocco, James; Deschler, Daniel G

    2011-03-01

    The authors examined the feasibility and advantages of primary tracheoesophageal puncture (TEP) with intraoperative placement of the voice prosthesis for patients undergoing laryngopharyngectomy requiring free tissue reconstruction and salivary bypass tube placement. Six patients were identified; 4 underwent total laryngopharyngectomy, and 2 underwent total laryngectomy with partial pharyngectomy. All 6 required free tissue reconstruction, and a salivary bypass tube was placed in all cases. All patients had a 20F Indwelling Blom-Singer prosthesis (InHealth Technologies, Carpinteria, California) placed. No complications were noted with intraoperative prosthesis placement. No prostheses were dislodged in the postoperative period. At 6 months, 4 patients available for evaluation had successful voice outcomes, and 3 were disease free. This study demonstrates the effectiveness of voice prosthesis placement at the time of primary TEP associated with free tissue reconstruction of a laryngopharyngeal defect with salivary bypass tube placement.

  4. The price of placements in residential and nursing home care: the effects of contracts and competition.

    PubMed

    Forder, J; Netten, A

    2000-10-01

    A variety of contract types are used in the placement of elderly people in residential and nursing care homes in the UK. Contracts vary according to how and when providers are paid. Among other things, prices can be made contingent on the total quantity of service to be purchased and on production cost characteristics. They can be determined at the time of placement or in advance. The primary objective of this paper is to assess the impact of contract choices on the price of placements. Regression analysis was conducted on a final sample of 1780 publicly funded placements made in 18 local authorities in the UK over a 6-month period ending in early 1996. Controlling factors included in the price analysis were production cost indicators and those measuring market competitiveness. Choices of both quantity and cost contingent contracts were found to be significantly associated with placement prices. The findings support the hypothesis that contract payment arrangements have different risk, insurance and information properties, and so have implications for the performance of residential care providers.

  5. Hydrates in the California Borderlands: 2D CSEM inversion results from towed and seafloor arrays

    NASA Astrophysics Data System (ADS)

    Kannberg, P. K.; Constable, S.; Key, K.

    2013-12-01

    Methane hydrate, an ice-like solid clathrate of methane and water, forms in shallow continental slope sediments, and is both a potential energy source and geologic hazard. Traditionally, methane hydrate presence is inferred from a seismically detected bathymetry tracking velocity inversion, known as the bottom-simulating reflector (BSR). However the BSR is an indicator of free gas at the base of the hydrate stability zone, and not an indicator of hydrate. As such, seismic methods are limited in their capacity to identify and quantify hydrate presence and concentration. Controlled source electromagnetic (CSEM) methods are sensitive to, and are able to directly detect, the presence of electrically resistive methane hydrate and free gas. Additionally, because shallow resistors can mimic deeper resistors in seafloor instruments, understanding the shallow sediment structure can inform deeper crustal modeling. We conducted two CSEM surveys in the San Nicolas Basin, located 150km west of San Diego where a BSR was identified from legacy seismics. Both surveys were conducted using a deep-towed EM transmitter followed by 4 towed 3-axis electric field receivers spaced every 200 m from 400-1000 m behind the transmitter. Either a half-hertz or quarter-hertz modified square wave was transmitted on a 200 ampere, 100 m dipole that was flown between 50 and 100m above the seafloor. The short transmitter-receiver offset allows resolution of shallow structure (less than 1km below seafloor), while the longer transmitter-seafloor receiver resolves deeper structure. Between the two surveys, 27 seafloor receivers were deployed and ~150km of lines were towed, including 5 transects of the basin coincident with legacy seismic lines, and a short-offset repeatability study. Initial 1D modeling showed the presence of a resistor coincident with the BSR. Further 2D inversions using the MARE2DEM inversion program were run for the towed array. These inversions show a 4 ohm-m resistor in the central

  6. Functional clinical placements: a driver for change.

    PubMed

    Goddard, L; Mackey, S; Davidson, P M

    2010-07-01

    The aim of the project was to create a supervised professional experience placement model involving undergraduate nursing students, families of children with intellectual disabilities and nursing lecturers. Action research provided the methodological framework for developing a new placement model. Five families with children with disabilities, nine nursing students and two nurse academics worked together through the cycles of the action research process to develop a family health promotion intervention to improve the health and wellness of the family members and reduce risk for illness. Awareness, valuing and understanding were key themes derived from the qualitative data. Findings of this project indicate that this model of university-initiated, community-focused professional experience placement is effective in achieving the competency-based learning outcomes required of undergraduate nursing students and is worthy of ongoing exploration.

  7. Macro cell placement with neural net algorithms

    NASA Astrophysics Data System (ADS)

    Storti-Gajani, Giancarlo

    Placement of VLSI (Very Large Scale Integration) macro cells is one of the hard problems encountered in the process of integrated circuits design. Since the problem is essentially NP-complete a solution must be searched for with the aid of heuristics using, maybe, non deterministic strategies. A new algorithm for cell preplacement based on neural nets that may be very well extended to find solution of the final placement problem is presented. Simulations for the part of the algorithm concerning preplacement are carried out on several different examples giving always a sharply decreasing cost function (where cost is evaluated essentially on total length of wires given a rectangular boundary). The direct mapping between neural units and VLSI blocks that is adopted in the algorithm makes the extension to the final placement problem quite simple. Simulation programs are implemented in a interpreted mathematical simulation language and a C language implementation is currently under way.

  8. Tools and Techniques for Placement Experiments

    NASA Astrophysics Data System (ADS)

    van der Vegt, Wim; Kalz, Marco; Giesbers, Bas; Wild, Fridolin; van Bruggen, Jan

    In Chap. 11 we presented placement in the context of Accreditation of Prior Learning and showed that in the scenario we address we do not assume the availability of controlled vocabulary with which the contents of the learner portfolio or the learning material in the learning network is described. Our placement service is based on the assumption that similarity between material produced or studied by the learner on the one hand and the learning material of the learning network on the other, can be used as a proxy to similarity in learning outcomes. The first task of any such placement service is therefore to establish whether these similarities are present for a given learner. The technology with which this is done, latent semantic analysis, is presented here. The emphasis here is on the technical and computational aspects of data preparation and analysis.

  9. M2-F1 on lakebed with Pontiac convertible tow vehicle

    NASA Technical Reports Server (NTRS)

    1963-01-01

    The M2-F1 lifting body, dubbed the 'flying bathtub' by the media, was the precursor of a remarkable series of wingless flying vehicles that contributed data used in the space shuttle and the X-38 Technology Demonstrator for crew return from the International Space Station. The early tow tests were done using the 1963 Pontiac Catalina convertible modified for the purpose. The first flight attempt occurred on 1 March 1963 but was unsuccessful due to control-system problems. It was not until 5 April 1963, after tests in the Ames Research Center wind tunnel, that Milt Thompson made the first M2-F1 tow flight. Based on the ideas and basic design of Alfred J. Eggers and others at the Ames Aeronautical Laboratory (now the Ames Research Center), Mountain View, Calif., in the mid-1950s, the M2-F1 came to be built over a four-month period in 1962-63 for a cost of only about $30,000 plus perhaps an additional $8,000-$10,000 for an ejection seat and $10,000 for solid-propellant rockets to add time to the landing flare. Engineers and technicians at the NASA Flight Research Center (now NASA Dryden) kept costs low by designing and fabricating it partly in-house, with the plywood shell constructed by a local sailplane builder. Someone at the time estimated that it would have cost a major aircraft company $150,000 to build the same vehicle. Unlike the later lifting bodies, the M2-F1 was unpowered and was initially towed until it was airborne by a souped-up Pontiac convertible. This vehicle needed to be able to tow the M2-F1 on the Rogers Dry Lakebed adjacent to NASA's Flight Research Center (FRC) at a minimum speed of 100 miles per hour. To do that, it had to handle the 400-pound pull of the M2-F1. Walter 'Whitey' Whiteside, who was a retired Air Force maintenance officer working in the FRC's Flight Operations Division, was a dirt-bike rider and hot-rodder. Together with Boyden 'Bud' Bearce in the Procurement and Supply Branch of the FRC, Whitey acquired a Pontiac Catalina

  10. Elbow arthroscopy: setup, portal placement, and simple procedures.

    PubMed

    Ahmad, Christopher S; Vitale, Mark A

    2011-01-01

    Elbow arthroscopy has become an accepted treatment for numerous elbow conditions, including loose bodies, lateral epicondylitis, contractures, painful osteophytes, synovitis, osteochondritis dissecans, synovial plica, and osteoarthritis. It is absolutely necessary that the treating surgeon have complete knowledge of elbow anatomy. Three options exist for patient positioning: supine, prone, and lateral decubitus. Standard arthroscopic probes, grasping forceps, punches, and motorized shavers and burrs are used in the procedure. Retractors are essential for visualizing, exposing, and protecting nerves. Specially designed capsular biters can be used to develop a plane between the capsule and the surrounding soft tissues to facilitate capsulotomy and capsulectomy. Among elbow arthroscopists, the sequence of portal placement varies; however, there is little variation in the exact location of portal placement because of neurovascular constraints. Loose body removal and extensor carpi radialis brevis release for lateral epicondylitis are common procedures suitable for the beginning arthroscopist. For beginning and advanced procedures, the surgeon's skill and competence must be at a level consistent with the procedure to avoid complications.

  11. Optimization Strategies for Sensor and Actuator Placement

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Kincaid, Rex K.

    1999-01-01

    This paper provides a survey of actuator and sensor placement problems from a wide range of engineering disciplines and a variety of applications. Combinatorial optimization methods are recommended as a means for identifying sets of actuators and sensors that maximize performance. Several sample applications from NASA Langley Research Center, such as active structural acoustic control, are covered in detail. Laboratory and flight tests of these applications indicate that actuator and sensor placement methods are effective and important. Lessons learned in solving these optimization problems can guide future research.

  12. Trajectory surgical guide stent for implant placement.

    PubMed

    Adrian, E D; Ivanhoe, J R; Krantz, W A

    1992-05-01

    This article describes a new implant placement surgical guide that gives both implant location and trajectory to the surgeon. Radiopaque markers are placed on diagnostic dentures and a lateral cephalometric radiograph is made that shows the osseous anatomy at the symphysis and the anterior tooth location. The ideal implant location and trajectory data are transferred to a surgical stent that programs the angle and location of the fixtures at time of surgery. The stent has the additional benefit of acting as an occlusion rim, a mouth prop, and tongue retractor. Use of this stent has resulted in consistently programming the placement of implant fixtures that are prosthodontically ideal.

  13. Performance consequences of parity placement in disk arrays

    NASA Technical Reports Server (NTRS)

    Lee, Edward K.; Katz, Randy H.

    1991-01-01

    The performance of a variety of parity placement schemes are defined and investigated to demonstrate that, at relatively large request sizes of hundreds of kilobytes, the choice of parity placement significantly affects performance (20 to 30 percent for the disk array configurations that are common today). It is shown that the left-symmetric, extended-left-symmetric and flat-left-symmetric are the best RAID level 5 parity placements. The placement with the highest read performance, flat-left-symmetric, has the lowest write performance, while the placement with the lowest read performance, left-symmetric, has the highest write performance. Suggestions for optimizing parity placements are included.

  14. Piezoceramic Actuator Placement for Acoustic Control of Panels

    NASA Technical Reports Server (NTRS)

    Bevan, Jeffrey S.

    2000-01-01

    Optimum placement of multiple traditional piezoceramic actuators is determined for active structural acoustic control of flat panels. The structural acoustic response is determined using acoustic radiation filters and structural surface vibration characteristics. Linear Quadratic Regulator (LQR) control is utilized to determine the optimum state feedback gain for active structural acoustic control. The optimum actuator location is determined by minimizing the structural acoustic radiated noise using a modified genetic algorithm. Experimental tests are conducted and compared to analytical results. Anisotropic piezoceramic actuators exhibit enhanced performance when compared to traditional isotropic piezoceramic actuators. As a result of the inherent isotropy, these advanced actuators develop strain along the principal material axis. The orientation of anisotropic actuators is investigated on the effect of structural vibration and acoustic control of curved and flat panels. A fully coupled shallow shell finite element formulation is developed to include anisotropic piezoceramic actuators for shell structures.

  15. Piezoceramic Actuator Placement for Acoustic Control of Panels

    NASA Technical Reports Server (NTRS)

    Bevan, Jeffrey S.; Turner, Travis L. (Technical Monitor)

    2001-01-01

    Optimum placement of multiple traditional piezoceramic actuators is determined for active structural acoustic control of flat panels. The structural acoustic response is determined using acoustic radiation filters and structural surface vibration characteristics. Linear Quadratic Regulator (LQR) control is utilized to determine the optimum state feedback gain for active structural acoustic control. The optimum actuator location is determined by minimizing the structural acoustic radiated noise using a modified genetic algorithm. Experimental tests are conducted and compared to analytical results. Anisotropic piezoceramic actuators exhibits enhanced performance when compared to traditional isotropic piezoceramic actuators. As a result of the inherent isotropy, these advanced actuators develop strain along the principal material axis. The orientation of anisotropic actuators is investigated on the effect of structural vibration and acoustic control of curved and flat panels. A fully coupled shallow shell finite element formulation is developed to include anisotropic piezoceramic actuators for shell structures.

  16. Linking Services to Increased Productivity in Placement.

    ERIC Educational Resources Information Center

    Bostaph, Charles P.; Martoni, Charles J.

    1984-01-01

    Looks at the way Pennsylvania Job Search was brought to the Boyce Campus of Community College of Allegheny County. Discusses student and community participants in the job placement program, its unique services, benefits to the campus, and use of the model by other schools. (AYC)

  17. Placement of Engineering and Technology Graduates, 1980.

    ERIC Educational Resources Information Center

    Gilmore, Arthur W.

    Information on the placement status of 1980 engineering and technology graduates is presented. At the doctoral degree level, the percentage without job offers or other firm plans was lower than in 1979. The bachelor's degree level experienced a one percentage point reduction in the number of graduates employed as of graduation compared to 1979,…

  18. CAPS: Career Assistance & Placement Services. Resource Manual.

    ERIC Educational Resources Information Center

    Barrow, Connye M.; And Others

    This resource manual describes a model for planning and developing comprehensive career placement services integrated into the total career development efforts of secondary and postsecondary schools in Illinois. The manual is designed to be used by educational administrators at the local and regional level in developing specific program goals,…

  19. Health risks for students on overseas placements.

    PubMed

    Driver, Carolyn

    Health profession students are encouraged to take an elective during training and many do this overseas in tropical, low-income countries. Higher education institutions should offer advice and support on organising these placements but this varies and students may present for pre-travel health advice at their general practice or travel clinic. This article discusses how they should be advised.

  20. Online Placement in First-Year Writing

    ERIC Educational Resources Information Center

    Peckham, Irvin

    2009-01-01

    This essay describes Louisiana State University's search for an alternative to available placement protocols. Under the leadership of Les Perelman at MIT, LSU collaborated with four universities to develop iMOAT, a program for administering online assessments of student writing. This essay focuses on LSU's On-line Challenge, which developed from…